U.S. patent application number 11/057352 was filed with the patent office on 2005-07-07 for av data recording apparatus and method, and disk recorded by the same.
This patent application is currently assigned to Matsushita Electric Industrial Co., Ltd.. Invention is credited to Hino, Yasumori, Itoh, Masanori, Nakamura, Tadashi, Shimotashiro, Masafumi.
Application Number | 20050147389 11/057352 |
Document ID | / |
Family ID | 26523178 |
Filed Date | 2005-07-07 |
United States Patent
Application |
20050147389 |
Kind Code |
A1 |
Nakamura, Tadashi ; et
al. |
July 7, 2005 |
AV data recording apparatus and method, and disk recorded by the
same
Abstract
An AV data recording apparatus and an AV data recording method
are provided, in which even in the case of using the UDF file
system, seeking can be minimized. The AV data recording method has
file management information for managing continuous blocks on a
disk as an extent, and dividing the extent into groups so as to
manage the extent as a file, wherein a new directory is created on
a disk, and a not recorded but allocated extent is kept as a
reservation region for recording file management information.
Inventors: |
Nakamura, Tadashi;
(Katano-shi, JP) ; Itoh, Masanori; (Moriguchi-shi,
JP) ; Hino, Yasumori; (Ikoma-shi, JP) ;
Shimotashiro, Masafumi; (Katano-shi, JP) |
Correspondence
Address: |
MERCHANT & GOULD PC
P.O. BOX 2903
MINNEAPOLIS
MN
55402-0903
US
|
Assignee: |
Matsushita Electric Industrial Co.,
Ltd.
Kadoma-shi
JP
|
Family ID: |
26523178 |
Appl. No.: |
11/057352 |
Filed: |
February 14, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11057352 |
Feb 14, 2005 |
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09629744 |
Jul 31, 2000 |
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6873789 |
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Current U.S.
Class: |
386/241 ;
386/248; 386/326; 386/E9.013; G9B/27.012; G9B/27.05 |
Current CPC
Class: |
G11B 2220/2575 20130101;
G11B 27/36 20130101; H04N 5/85 20130101; G06F 3/0601 20130101; G11B
2220/2525 20130101; G11B 2220/65 20130101; G11B 27/34 20130101;
G11B 27/11 20130101; G11B 2220/216 20130101; G11B 2220/2562
20130101; G11B 27/326 20130101; G11B 27/329 20130101; H04N 9/8042
20130101; G11B 2220/213 20130101; G06F 2003/0697 20130101; G11B
27/034 20130101; G11B 2220/218 20130101; G06F 16/10 20190101 |
Class at
Publication: |
386/095 ;
386/125 |
International
Class: |
H04N 005/781 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 3, 1999 |
JP |
11-219523 |
Feb 10, 2000 |
JP |
2000-33538 |
Claims
1-26. (canceled)
27. An AV data recording apparatus, comprising: a
recording/reproducing section for recording AV data onto a disk and
reproducing the recorded AV data; and a system control section for
controlling a method of recording/reproducing AV data, wherein the
apparatus has extent management information for managing continuous
blocks on the disk as an extent, the apparatus has file management
information for managing a group of the extents as a file, the
apparatus has directory information for managing a group of the
files as a directory, an area in a user area is kept as a
reservation extent for recording at least any one of the directory
information, the file management information, a part of the file,
and a whole of the file, information concerning the position and
capacity of the reservation extent is recorded previously on the
disk, the information concerning the reservation extent being
different from said any one of the directory information, the file
management information, the part of the file or the whole of the
file, and when the reservation extent is kept, a defective block in
the reservation extent is detected, and data is recorded in the
reservation extent, the defective block is skipped and the data is
recorded.
28. An AV data recording method, comprising: recording AV data onto
a disk and reproducing the recorded AV data; controlling a method
of recording/reproducing AV data; using extent management
information for managing continuous blocks on the disk as an
extent, using file management information for managing a group of
extents as a file, using directory information for managing a group
of the files as a directory, keeping an area in a user area as a
reservation extent for recording at least any one of the directory
information, the file management information, a part of the file,
and a whole of the file, recording previously on the disk
information concerning the position and capacity of the reservation
extent, the information concerning the reservation extent being
different from said any one of the directory information, the file
management information, the part of the file or the whole of the
file and when the reservation extent is kept, a defective block in
the reservation extent is detected, and data is recorded in the
reservation extent, skipping the defective block and recording the
data.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an AV data recording
apparatus and method, suitable for recording/reproducing AV
(audio-video) data such as a digital image.
[0003] 2. Description of the Related Art
[0004] In recent years, optical disks are being used as recording
media for recording digital images including animation, due to
their increased density. Optical disks are applied in a wide range;
specifically, they are applied to peripheral equipment of
computers, video players for use at home, etc. Furthermore, it is
expected that optical disks will be used as recording media, in
place of tape media in the future.
[0005] In order to handle data for common use in such a wide range
of applications, data generally is managed as a logical unit (i.e.,
file). As an example of such a file management method, there is a
file system using a format based on the UDF (Universal Disk Format)
standard.
[0006] The UDF standard is prescribed so as to ensure medium
compatibility among various kinds of computer OSes (Operating
Systems). The UDF standard also is used in consumer equipment such
as DVD-Video players. Furthermore, it is expected that the UDF
standard will be supported over a wider platform in the future.
[0007] Hereinafter, the structure of a file system (hereinafter,
referred to as a "UDF file system") using the UDF standard will be
described with reference to the drawings. FIG. 35 shows an example
of a structure of an apparatus for recording/reproducing data
adopting a conventional AV data recording method.
[0008] In FIG. 35, reference numeral 101 denotes a disk (e.g., a
magneto-optical disk), and 102 denotes a recording medium driving
section. When the disk 101 is, for example, a magneto-optical disk,
the recording medium driving section 102 may be composed of a
spindle motor, or the like.
[0009] Reference numeral 103 denotes a recording/reproducing
section, which is composed of an optical pickup, a magnetic head, a
servo circuit, a modulation/demodulation circuit, and the like,
when the disk 101 is, for example, a magneto-optical disk.
Reference numeral 104 denotes a memory section, which stores data
temporarily during recording/reproduction. Reference numeral 105
denotes a disk drive unit, which is composed of the disk 101, the
recording medium driving section 102, the recording/reproducing
section 103, and the memory section 104.
[0010] Reference numeral 106 denotes an AV signal processing
section, which subjects an AV input signal (that is input through a
CCD camera, for example) to processing such as MPEG compression or
subjects AV data read from the disk 101 to processing such as MPEG
decoding, and outputs the results to a monitor or the like.
[0011] Furthermore, reference numeral 107 denotes a system control
section, which controls the AV signal processing section 106 and
the disk drive unit 105.
[0012] When data is recorded in an apparatus for
recording/reproducing data thus constructed, an AV signal input to
the AV signal processing section 106 is subjected to image
compression in accordance with the MPEG system or the like, and
transferred to the memory section 104 under the control of the
system control section 107.
[0013] Next, the system control section 107 operates the recording
medium driving section 102 and the recording/reproducing section
103 to record data in the memory section 104 onto the disk 101.
[0014] For reproduction of data, the system control section 107
operates the recording medium driving section 102 and the
recording/reproducing section 103 to transfer data recorded on the
disk 101 to the memory section 104.
[0015] Then, the data in the memory section 104 is read under the
control of the system control section 107, and is output from the
AV signal processing section 106 as an AV signal.
[0016] Next, an example of a structure of the UDF file system that
is a conventional file management method will be described with
reference to the drawings. FIG. 36 shows the structure in a volume
space of the UDF formed on the disk 101.
[0017] In FIG. 36, in order to handle the disk 101 as a logical
volume, the disk 101 is divided into units called sectors, and the
sectors are assigned logical sector numbers (LSNs) from 0 (Zero) to
a last logical number (Last LSN). In a leading portion and a
trailing portion of the volume space, a volume structure is
recorded, respectively. Furthermore, a partition space is allocated
between the volume structures. In the partition space, file
structure information and a file (i.e., user data) are
recorded.
[0018] In the partition space, logical block numbers (LBNs) are
allocated in a range of 0 (Zero) to a last logical block number
(Last LBN) from a leading sector on a sector basis. FIG. 37 shows a
structure of the partition space when a directory structure shown
in FIG. 38 is recorded on the disk 101.
[0019] As shown in FIG. 38, a directory Dir1 is present under a
root directory, and File1_1 and File1_2 are present under the
directory Dir1. In this case, in FIG. 37, a space bitmap descriptor
is recorded in LBN=0 to 79.
[0020] The space bitmap descriptor has a space bitmap showing
whether or not each logical block is allocatable. Each bit of the
space bitmap corresponds to a respective logical block. When a bit
value is "1", its corresponding logical block is unallocated, and
when a bit value is "0", its corresponding logical block is
allocated.
[0021] In LBN=80, a file set descriptor is recorded. In the file
set descriptor, positional information of a file entry of the root
directory is recorded. The file entry will be described in detail
later.
[0022] In LBN=81, a terminating descriptor is recorded. The
terminating descriptor represents an end of a file set descriptor
string.
[0023] In LBN=82, a file entry of the root directory is recorded.
The file entry is used for storing various pieces of attribute
information specific to each file, information on the recorded
position and size of each file, and the like, and managing each
file as a group of extents. The extent will be described in detail
later.
[0024] FIG. 39 shows a structure of the file entry. In a descriptor
tag field, information is recorded for identifying various kinds of
descriptors such as a space bitmap descriptor, a file set
descriptor, and a file entry in the partition space. In the case of
the file entry, "261" is described. In an ICB (Information Control
Block) tag field, attribute information on the file entry itself is
recorded. An extended attribute field is used for describing
attribute information other than that prescribed in an attribute
information field in the file entry. In an allocation descriptor
field, the required number of allocation descriptors are recorded
for managing a region of continuous logical blocks as one
extent.
[0025] FIG. 40 shows a structure of the allocation descriptor. In
the allocation descriptor, an extent is represented by an extent
length and an extent position.
[0026] FIG. 41 shows interpretation of the 2 most significant bits
of the extent length included in the allocation descriptor. An
allocated state and a recorded state of the extent are represented
by the value of the 2 most significant bits. The value "0"
represents an extent recorded and allocated, and file data is
recorded therein. The value "1" represents an extent not recorded
but allocated, and its region is allocated to a particular
file/directory; however, no data is recorded therein. The value "2"
represents an extent not recorded and not allocated, and no data is
recorded therein. The value "3" represents the extent that is the
next extent of the allocation descriptors. In the allocation
descriptor field of the file entry, a plurality of allocation
descriptors can be recorded, and collection of extents managed by
these allocation descriptors form one file. The extents forming a
file are called a main data stream, in which user data is
stored.
[0027] In a directory, a name of a file included in the directory,
and positional information on a file entry thereof are recorded. In
the UDF, a directory also is a kind of a file. Referring to FIG.
37, directories are recorded in LBN=83 and LBN=85.
[0028] FIG. 42 shows an example of a structure of a directory file
recorded in LBN=85. The directory file is composed of a plurality
of file identifier descriptors, and each file identifier descriptor
has information on each file included in the directory. The main
information associated with each file identifier descriptor
includes a name of a file to which the file identifier descriptor
corresponds and positional information on a file entry thereof FIG.
43 shows an example of the logical structure of a directory/file in
file management information in accordance with the UDF
standard.
[0029] In FIG. 43, the file set descriptor is recorded at a
predetermined position in the partition space as a part of file
management information. In the file set descriptor, a recorded
position of the file entry of the root directory file is stored. In
the file identifier descriptor of the root directory file, a
recorded position of the file entry of the directory Dir1 is
stored. In a file under the directory Dir1, a plurality of file
identifier descriptors are present, and file names and recorded
positions of file entries of FILE1_1 and FILE1_2 are stored,
respectively.
[0030] Furthermore, according to the UDF, an extended file entry
can be used in place of the above-mentioned file entry. FIG. 44
shows an example of a structure of an extended file entry. In the
UDF standard, in a descriptor tag field of the extended file entry,
"266" is described.
[0031] The extended file entry is different from the file entry, in
that the extended file entry has a stream directory ICB field. In
the stream directory ICB, positional information on a file entry
for describing a special directory called a stream directory is
stored.
[0032] FIG. 45 shows an example of a structure of the stream
directory. The stream directory also is a kind of a directory file,
and is composed of a plurality of file identifier descriptors in
the same way as in a general directory file.
[0033] The stream directory file is different from a general
directory file, in that a file identifier descriptor in the stream
directory is related to a special file called a named data
stream.
[0034] Furthermore, in the stream directory, a main data stream is
referred to as a parent entry, in place of a parent directory.
[0035] In the case of the named data stream, the collection of
extents managed by allocation descriptors in an extended file entry
also forms one data stream.
[0036] Accordingly, a file managed by an extended file entry is
composed of one main data stream, or one main data stream and at
least one named data stream.
[0037] FIG. 46 shows an example of a directory/file logical
structure when an extended file entry is used in accordance with
the UDF standard. In FIG. 46, the relationship among a file set
descriptor, a root directory, a directory Dir1, and files FILE1_1
and FILE_2 is the same as that shown in FIG. 43, except that an
extended file entry is used in place of a file entry.
[0038] Referring to FIG. 44, in the stream directory ICB field of
the extended file entry, a recorded position of a file entry in the
stream directory is stored.
[0039] In a file under the stream directory, a plurality of file
identifier descriptors are present, and names and recorded
positions of extended file entries of named_stream_1 and
named_stream_2 are stored in the respective file identifier
descriptors.
[0040] Referring to FIG. 46, in the directory Dir1, three data
streams: a directory file (main data stream), and named_stream_1
and named_stream_2 (named data streams) form one file.
[0041] Hereinafter, an operation of an apparatus for
recording/reproducing data will be described, in which a desired
file is read from a disk having a structure in accordance with the
above-mentioned UDF file system.
[0042] An operation of obtaining a recorded position of an intended
file in a hierarchical structure as shown in FIG. 43 will be
described. It is assumed that a file FILE1_1 is the intended
one.
[0043] First, the content of a root directory file is read. More
specifically, a position of a file entry of the root directory is
obtained by referring to a file set descriptor. Then, an allocation
descriptor is read from the file entry to obtain the position and
length of an extent of the root directory file, and data of the
root directory file are read. By scanning information on the root
directory file thus obtained, a file identifier descriptor matched
with an intended directory name Dir1 can be detected.
[0044] Then, the content of the intended directory file is read.
More specifically, when a file identifier descriptor matched with
an intended directory is detected, positional information of a file
entry is obtained from the content of the file identifier
descriptor, and the file entry is read. An allocation descriptor is
read from the file entry regarding the intended directory to obtain
the position and length of an extent recorded in the allocation
descriptor, and data of the directory file are read.
[0045] Finally, in order to read an intended file, data in a file
under the directory Dir1 are scanned to detect a file identifier
descriptor matched with an intended file name FILE1_1. When a file
identifier descriptor matched with the intended file name is
detected, positional information of a file entry is obtained from
the file identifier descriptor, and a file entry thereof is read.
An allocation descriptor is read from the file entry to obtain the
position and length of an extent recorded in the allocation
descriptor, and data of the intended file FILE1_1 is read.
[0046] Next, an operation of an apparatus for recording/reproducing
data will be described, in which data are recorded on a disk having
a structure based on the UDF file system. Herein, the case will be
described where FILE1_3 is further recorded in the directory Dir1
with respect to a disk having the partition space shown in FIG.
37.
[0047] First, a space bitmap is scanned, and an unallocated logical
block with a bit "1" is obtained. Data of FILE1_3 is recorded as an
extent in the unallocated logical block. When recording of the
extent is completed, a file entry indicating FILE1_3 is recorded in
the unallocated logical block.
[0048] At this time, positional information on the extent
indicating FILE1_3 and the extent length are recorded in the file
entry as a required number of allocation descriptors. A file
identifier descriptor indicating FILE1_3 is recorded in a file of a
directory Dir1 that is a parent directory of FILE1_3.
[0049] In the file identifier descriptor, a file name of FILE1_3
and positional information of the file entry thereof are recorded.
A bit in the space bitmap corresponding to a sector that has been
allocated by the above processing is set at "0" so as to be in an
allocated state.
[0050] FIG. 47 shows a logical volume space obtained as a result of
the above processing. The order of processing with respect to file
management information is not particularly limited to the above
example. The processing may be performed in a different order.
[0051] Hereinafter, an operation of an apparatus for
recording/reproducing apparatus will be described in which a
desired named data stream is read from a disk having a structure
based on the UDF file system. Herein, an operation of obtaining a
recorded position of an intended named data stream in a
hierarchical structure as shown in FIG. 46 will be described. In
FIG. 46, it is assumed that named-stream_1 is the intended data
stream.
[0052] An operation of reading a file entry of a directory Dir1
that is a parent directory of the named data stream named_stream_1
is as described above.
[0053] A stream directory ICB is read from an extended file entry
of the directory Dir1, and an extended file entry of a stream
directory recorded therein is obtained.
[0054] Then, an allocation descriptor is read from the extended
file entry to obtain the position and length of an extent of the
stream directory, and data of the stream directory file is
read.
[0055] Information on the obtained stream directory is scanned,
whereby a file identifier descriptor matched with the name of the
intended named data stream (i.e., named_stream_1) can be
detected.
[0056] Positional information of an extended file entry is obtained
from the content of the file identifier descriptor, and the
extended file entry is read.
[0057] An allocation descriptor is read from the extended file
entry regarding the named data stream to obtain the position and
length of an extent recorded therein, and data of an intended named
data stream (named_stream_1) is read.
[0058] A named data stream also is recorded in the same way as in a
file, except that a file identifier descriptor for storing a
recorded position of an extended file entry of the named data
stream is recorded in a stream directory file.
[0059] The order of processing with respect to the named data
stream is not particularly limited to the above example, and the
processing may be performed in a different order.
[0060] However, the above-mentioned file management method using
the UDF has the following problem. More specifically, according to
the UDF, a directory is recorded as a file in a partition space,
and a file entry also is recorded in the partition space.
Therefore, the directory file and the file entry may be distributed
on a disk. Thus, in the case where it is attempted to read all the
files under a certain directory, when a directory file and a file
entry are distributed, seeking occurs often with respect to a
disk.
[0061] For example, referring to FIG. 47, file entries of FILE1_1,
FILE1_2, and FILE1_3 are distributed; therefore, seeking cannot be
avoided for reading them. When a file to be reproduced is the one
which requires real time reproduction, such as an AV file,
reproduction of the file may be difficult due to the occurrence of
seeking.
[0062] Similarly, in the case where real time recording is required
as in an AV file and the like, when a file entry is recorded after
AV data is recorded, seeking occurs with respect to a disk, and
recording of AV data during this time stops. This also applies to
the case where a large amount of still image files and the like
subjected to JPEG compression are recorded and browsed through.
[0063] It is conceivable to reduce seeking with respect to a disk
by reading all the file management information to a memory and
performing on-memory processing, upon activation of an apparatus.
Even in this case, seeking occurs a number times, which prolongs an
activation time. Furthermore, a required memory capacity cannot be
expected previously; therefore, it is difficult to construct a
system in which a calculator resource is disposed efficiently.
SUMMARY OF THE INVENTION
[0064] Therefore, with the foregoing in mind, it is an object of
the present invention to provide an AV data recording apparatus and
method capable of minimizing seeking even in the case of using the
UDF file system.
[0065] In order to achieve the above-mentioned object, the AV data
recording apparatus of the present invention, includes: a disk as a
recording medium for AV data; a recording medium driving section
for driving the disk; a recording/reproducing section for recording
data onto the disk/reproducing the data from the disk; a memory
section for storing data temporarily; an AV signal processing
section for performing conversion between an AV signal and a
digital signal; and a system control section for controlling a
recording method, wherein the apparatus has file management
information for managing continuous blocks on the disk as an
extent, and dividing the extent into groups so as to manage the
extent as a file in the system control section, and a new directory
is created on the disk, and the extent that has been allocated is
kept as a reservation region for recording the file management
information.
[0066] Because of the above-mentioned structure, even in the case
of using the UDF, file management information of a file to be
recorded is not distributed on a disk, and seeking with respect to
a disk can be minimized. Therefore, recording can be performed with
high reliability at a high speed. Furthermore, by allocating a
reservation region, other information can be prevented from being
recorded therein.
[0067] Furthermore, it is preferable that the reservation region is
a part of a main data stream.
[0068] Furthermore, it is preferable that the reservation region is
a part of a named data stream.
[0069] Furthermore, it is preferable that, when the file is
recorded on the disk, attribute information of the file is recorded
in the reservation region.
[0070] Furthermore, it is preferable that the file is a transport
stream of MPEG, and the attribute information of the file recorded
in the reservation region is a private stream containing a time map
table of a transport stream. In this case, special reproduction
such as fast-forward reproduction and fast-backward reproduction,
reproduction at a specified time, and the like can be performed
easily.
[0071] Furthermore, it is preferable that the file is an Exif image
file, and the attribute information of the file recorded in the
reservation region is additional information of the Exif image
file. Since thumbnail information and the like are contained in the
additional information, thumbnail information and the like can be
reproduced at a high speed by reading only the additional
information.
[0072] Furthermore, it is preferable that the reservation region is
kept by recording the file management information of the file
previously. In this case, it is not required to scan a non-recorded
region during recording of a file, so that seeking can be
reduced.
[0073] Furthermore, it is preferable that, when a new subdirectory
is created under the directory, an allocated extent is kept as a
reservation region for recording the file management information of
the file in the subdirectory. In this case, the same effect can be
expected even when an AV file is recorded in the subdirectory.
[0074] Furthermore, it is preferable that, when a new subdirectory
is created under the directory, a directory file of the
subdirectory is recorded in the reservation region. This is because
seeking can be reduced even in the case of recording an AV file in
the subdirectory.
[0075] Furthermore, it is preferable that, when the directory is
created, a defective block in the reservation region is detected,
and the defective block is skipped. In this case, the continuity of
data to be recorded in the reservation region is not impaired, so
that recording can be performed with high reliability.
[0076] Furthermore, it is preferable that, in a case where the file
is recorded on the disk, when a capacity of the reservation region
becomes insufficient, another reservation region different from the
first reservation region is kept in a continuous region on the disk
to record the file. In this case, by minimizing seeking,
recording/reproduction of AV data can be prevented from being
suspended.
[0077] Furthermore, it is preferable that, in a case where a
thumbnail file containing a thumbnail image of the file is recorded
on the disk, the thumbnail file is recorded in the reservation
region. In this case, since seeking does not occur, even a
thumbnail image with a large capacity containing a plurality of
pieces of image data can be displayed at a high speed.
[0078] In order to achieve the above-mentioned object, the AV data
recording method has file management information for managing
continuous blocks on a disk as an extent, and dividing the extent
into groups so as to manage the extent as a file, wherein a new
directory is created on the disk, and the extent that has been
allocated is kept as a reservation region for recording the file
management information.
[0079] Because of the above-mentioned structure, even in the case
of using the UDF, file management information of a file to be
recorded is not distributed in a disk, and seeking with respect to
a disk can be minimized. As a result, recording can be performed
with high reliability at a high speed. Furthermore, by allocating
the reservation region, other information can be prevented from
being recorded.
[0080] Furthermore, it is preferable that the reservation region is
a part of a main data stream.
[0081] Furthermore, it is preferable that the reservation region is
a part of a named data stream.
[0082] Furthermore, it is preferable that, when the file is
recorded onto the disk, attribute information of the file is
recorded in the reservation region.
[0083] Furthermore, it is preferable that the file is a transport
stream of MPEG, and the attribute information of the file recorded
in the reservation region is a private stream containing a time map
table of a transport stream. In this case, special reproduction
such as fast-forward reproduction and fast-backward reproduction,
reproduction at a specified time, and the like can be performed
easily.
[0084] Furthermore, it is preferable that the file is an Exif image
file, and the attribute information of the file recorded in the
reservation region is additional information of the Exif image
file. Since thumbnail information and the like are contained in the
additional information, thumbnail information and the like can be
reproduced at a high speed by reading only the additional
information.
[0085] Furthermore, it is preferable that the reservation region is
kept by recording the file management information of the file
previously. In this case, it is not required to scan a non-recorded
region during recording of a file, so that seeking can be
reduced.
[0086] Furthermore, it is preferable that, when a new subdirectory
is created under the directory, an allocated extent is kept as a
reservation region for recording file management information of the
file in the subdirectory. In this case, the same effect can be
expected even when an AV file is recorded in the subdirectory.
[0087] Furthermore, it is preferable that, when a new subdirectory
is created under the directory, a directory file of the
subdirectory is recorded in the reservation region. This is because
seeking can be reduced even in the case of recording an AV file in
the subdirectory.
[0088] Furthermore, it is preferable that, when the directory is
created, a defective block in the reservation region is detected,
and the defective block is skipped. In this case, the continuity of
data to be recorded in the reservation region is not impaired, so
that recording can be performed with high reliability.
[0089] Furthermore, in a case where the file is recorded onto the
disk, when a capacity of the reservation region becomes
insufficient, another reservation region different from the
reservation region is kept in a continuous region on the disk to
record the file. In this case, by minimizing seeking,
recording/reproduction of AV data can be prevented from being
suspended.
[0090] Furthermore, it is preferable that, in a case where a
thumbnail file containing a thumbnail image of the file is recorded
onto the disk, the thumbnail file is recorded in the reservation
region. In this case, since seeking does not occur, even thumbnail
image with a large capacity containing a plurality of pieces of
image data can be displayed at a high speed.
[0091] These and other advantages of the present invention will
become apparent to those skilled in the art upon reading and
understanding the following detailed description with reference to
the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0092] FIG. 1 shows a structure of an AV data recording apparatus
in Embodiment 1 of the present invention.
[0093] FIG. 2 illustrates an initial directory structure in the AV
data recording apparatus in Embodiment 1 of the present
invention.
[0094] FIG. 3 illustrates an initial partition space in the AV data
recording apparatus in Embodiment 1 of the present invention.
[0095] FIG. 4 is a flow chart showing recording processing of an AV
file in the AV data recording apparatus in Embodiment 1 of the
present invention.
[0096] FIG. 5 illustrates a partition space after an AV file is
recorded in the AV data recording apparatus in Embodiment 1 of the
present invention.
[0097] FIG. 6 illustrates an initial directory structure in the AV
data recording apparatus in Embodiment 2 of the present
invention.
[0098] FIG. 7 illustrates an initial partition space in the AV data
recording apparatus in Embodiment 2 of the present invention.
[0099] FIG. 8 illustrates an initial directory structure in the AV
data recording apparatus in Embodiment 3 of the present
invention.
[0100] FIG. 9 illustrates an initial partition space in the AV data
recording apparatus in Embodiment 3 of the present invention.
[0101] FIG. 10 illustrates an AV file structure in the AV data
recording apparatus in Embodiment 4 of the present invention.
[0102] FIG. 11 illustrates a time map in the AV data recording
apparatus in Embodiment 4 of the present invention.
[0103] FIG. 12 illustrates a time map in the AV data recording
apparatus in Embodiment 4 of the present invention.
[0104] FIG. 13 illustrates a time map in the AV data recording
apparatus in Embodiment 4 of the present invention.
[0105] FIG. 14 illustrates an initial partition space in the AV
data recording apparatus in Embodiment 4 of the present
invention.
[0106] FIG. 15 is a flow chart showing recording processing of an
AV file in the AV data recording apparatus in Embodiment 4 of the
present invention.
[0107] FIG. 16 illustrates a partition space after an AV file is
recorded in the AV data recording apparatus in Embodiment 4 of the
present invention
[0108] FIG. 17 illustrates a date structure of a still image file
in an AV data recording apparatus in Embodiment 5 of the present
invention.
[0109] FIG. 18 illustrates a date structure of a still image file
in the AV data recording apparatus in Embodiment 5 of the present
invention.
[0110] FIG. 19 illustrates a multi-directory structure in the AV
data recording apparatus in Embodiment 5 of the present
invention.
[0111] FIG. 20 illustrates an initial directory structure in the AV
data recording apparatus in Embodiment 6 of the present
invention.
[0112] FIG. 21 illustrates an initial partition space in the AV
data recording apparatus in Embodiment 6 of the present
invention.
[0113] FIG. 22 is a flow chart showing recording processing of an
AV file in the AV data recording apparatus in Embodiment 6 of the
present invention.
[0114] FIG. 23 illustrates a directory structure after a
subdirectory is created in the AV data recording apparatus in
Embodiment 6 of the present invention.
[0115] FIG. 24 illustrates a partition space after a subdirectory
is created in the AV data recording apparatus in Embodiment 6 of
the present invention.
[0116] FIG. 25 is a flow chart showing recording processing of an
AV file in the AV data recording apparatus in Embodiment 6 of the
present invention.
[0117] FIG. 26 illustrates a partition space after an AV file is
recorded in the AV data recording apparatus in Embodiment 6 of the
present invention.
[0118] FIG. 27 is a flow chart showing processing of creating a
subdirectory in an AV data recording apparatus in Embodiment 7 of
the present invention.
[0119] FIG. 28 illustrates a partition space after a subdirectory
is created in the AV data recording apparatus in Embodiment 7 of
the present invention.
[0120] FIG. 29 is a flow chart showing processing of recording AV
data under a subdirectory in the AV data recording apparatus in
Embodiment 7 of the present invention.
[0121] FIG. 30 illustrates a partition space after an AV file is
recorded in a subdirectory in the AV data recording apparatus in
Embodiment 7 of the present invention.
[0122] FIG. 31 illustrates a directory structure after a
subdirectory is created in the AV data recording apparatus in
Embodiment 7 of the present invention.
[0123] FIG. 32 illustrates a partition space before a new AV
reservation region is kept in an AV data recording apparatus in
Embodiment 10 of the present invention.
[0124] FIG. 33 is a flow chart showing processing of recording an
AV file in the AV, data recording apparatus in Embodiment 10 of the
present invention.
[0125] FIG. 34 illustrates a partition space after a new AV
reservation region is kept in the AV data recording apparatus in
Embodiment 10 of the present invention.
[0126] FIG. 35 shows a structure of a conventional AV data
recording apparatus.
[0127] FIG. 36 illustrates a volume space structure in the
conventional AV data recording apparatus.
[0128] FIG. 37 illustrates a partition space in the conventional AV
data recording apparatus.
[0129] FIG. 38 illustrates a directory structure in the
conventional AV data recording apparatus.
[0130] FIG. 39 illustrates a file entry in the conventional AV data
recording apparatus.
[0131] FIG. 40 illustrates an allocation descriptor in the
conventional AV data recording apparatus.
[0132] FIG. 41 illustrates interpretation of an extent length in
the conventional AV data recording apparatus.
[0133] FIG. 42 illustrates a structure of a directory file in the
conventional AV data recording apparatus.
[0134] FIG. 43 illustrates a hierarchical structure of a file in
the conventional AV data recording apparatus.
[0135] FIG. 44 illustrates an extended file entry in the
conventional AV data recording apparatus.
[0136] FIG. 45 illustrates a structure of a stream directory file
in the conventional AV data recording apparatus.
[0137] FIG. 46 illustrates a hierarchical structure of a named data
stream in the conventional AV data recording apparatus.
[0138] FIG. 47 illustrates a partition space after recorded in the
conventional AV data recording apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0139] Hereinafter, embodiments of an AV data recording apparatus
of the present invention will be described with reference to the
drawings. In the following description, a file containing voice
data and video data encoded in accordance with the MPEG system, the
JPEG system, or the like will be referred to as an "AV file". In
the present specification, disks collectively refer to recording
media having a disk shape, such as an optical disk, a hard disk,
and the like (e.g., DVD-RAM, MO, DVD-R, DVD-RW, DVD+RW, etc.).
Embodiment 1
[0140] FIG. 1 shows the structure of an AV data recording apparatus
in Embodiment 1 of the present invention. In FIG. 1, reference
numeral 1 denotes a disk (e.g., a magneto-optical disk), and 2
denotes a recording medium driving section, which may be composed
of a spindle motor, or the like, when the disk 1 is, for example, a
magneto-optical disk.
[0141] Reference numeral 3 denotes a recording/reproducing section.
When the disk 1 is, for example, a magneto-optical disk, the
recording/reproducing section 3 is composed of an optical pickup, a
magnetic head, a servo circuit, a modulation/demodulation circuit,
and the like. Reference numeral 4 denotes a memory section, which
temporarily stores data during recording/reproduction. Reference
numeral 5 denotes a disk drive unit, which is composed of the disk
1, the recording medium driving section 2, the
recording/reproducing section 3 and the memory section 4.
[0142] Reference numeral 6 denotes an AV signal processing section,
which subjects an AV input signal (that is input from a CCD camera,
for example) to processing such as MPEG compression or subjects AV
data read from the disk medium to processing such as MPEG decoding,
and outputs the results to a monitor or the like. Reference numeral
7 denotes a system control section, which controls the AV signal
processing section 6 and the disk drive unit 5.
[0143] When data is recorded in an AV data recording apparatus thus
constructed, an AV signal input to the AV signal processing section
6 is subjected to image compression processing based on the MPEG
system, and transferred to the memory section 4 under the control
of the system control section 7. Next, the system control section 7
operates the recording medium driving section 2 and the
recording/reproducing section 3 to record data in the memory
section 4 onto the disk 1.
[0144] When data is reproduced, the system control section 7
operates the recording medium driving section 2 and the
recording/reproducing section 3 to transfer data recorded on the
disk 1 to the memory section 4. Then, the data in the memory
section 4 is read under the control of the system control section
7, and is output from the AV signal processing section 6 as an AV
signal.
[0145] FIG. 2 illustrates a file/directory structure immediately
after a directory for recording an AV file is created in Embodiment
1 of the present invention. In FIG. 2, Root surrounded by an
ellipse represents a root directory, and AV_DIR1 represents a
directory for recording an AV file, respectively.
[0146] FIG. 3 illustrates a data structure in a partition space in
which the file/directory structure shown in FIG. 2 is recorded on a
disk used in the AV data recording apparatus in Embodiment 1 of the
present invention. In FIG. 3, in LBN=0 to 79, a space bitmap
descriptor is recorded. LBN=251 to Last is "unallocated".
Therefore, bits corresponding to the sectors therein are set at
"1".
[0147] Furthermore, in LBN=80, a file set descriptor is recorded.
When a file entry is that of the root directory, positional
information thereof is recorded in the file set descriptor.
Furthermore, in LBN=81, a terminating descriptor is recorded.
[0148] Furthermore, a file entry of the root directory, a directory
file of the root directory, and a file entry of the directory
AV_DIR1 are recorded in LBN=82, LBN=83, and LBN=84,
respectively.
[0149] LBN=85 is an extent (1) in which a directory file of the
directory AV_DIR1 is recorded. Similarly, LBN=86 to 250 is an
extent (2) of the directory AV_DIR1. The value of the 2 most
significant bits of an allocation descriptor is determined so that
the extent (2) is "not recorded" but "allocated". Thus, in an
operation of a conventional file system, data cannot be written in
LBN=86 to 250. Hereinafter, the extent (2) will be referred to as
an "AV reservation region". Since LBN=0 to 250 is "allocated" as
described above, corresponding bits in the space bitmap are set at
"0" (Zero).
[0150] In Embodiment 1, the capacity of the "not recorded" but
"allocated" extent in the directory AV_DIR1 in an initial state of
the recording medium is previously determined. Because of this, in
recording/reproduction with respect to the disk 1 as shown in FIG.
4 (Step S401), a system structure is obtained in which the content
of LBN=0 to 250 on the disk 1 is read to the memory section 4, and
seeking during recording/reproduction can be reduced.
[0151] FIG. 4 is a flow chart showing the process of recording an
AV file onto a disk having the above-mentioned data structure. When
an AV file starts being recorded in accordance with a user's
instruction or the like, the content of LBN=0 to 250 on the disk 1
is read to the memory section 4 (Step S401). Then, information in
the AV reservation region in the memory section 4 is scanned to
determine whether or not there is a non-recorded region sufficient
for newly recording a file identifier descriptor and a file entry
(Step S402). If it is determined that there is not a sufficient
non-recorded region (Step S402: No), error processing is performed,
and recording of an AV file is ended. If it is determined that
there is a sufficient non-recorded region, a file identifier
descriptor and a file entry are recorded in a non-recorded region
in the AV reservation region in the memory section 4 (Step
S403).
[0152] At this time, the size of the extent of the directory
AV_DIR1 is changed due to recording of the file identifier
descriptor and the file entry, so that an allocation descriptor of
the file entry of the directory AV_DIR1 is rewritten in accordance
with the change. More specifically, the extent length of the extent
(1) is changed by addition of the file identifier descriptor, and a
portion in which the file entry has been recorded is excluded from
the extent (2).
[0153] Next, the space bitmap in the memory section 4 is scanned to
determine whether or not there are the required number of
unallocated logical blocks for recording an AV file (Step S404). If
it is determined that there are no required number of unallocated
logical blocks (Step S404: No), error processing is performed, and
recording of an AV file is ended. When it is determined that there
are the required number of unallocated logical blocks, data are
recorded in logical blocks on the recording medium corresponding to
the unallocated region obtained in Step S404 (Step S405).
[0154] When recording of AV file data is completed, in order to
update the file management information of an AV file, information
on the position and length of the extent of the AV file is recorded
in an allocation descriptor in the file entry in the memory section
4 created in Step 403 (Step S406). Furthermore, required
information such as a file name and a file creation time also are
updated with respect to the file identifier descriptor and the file
entry, in addition to the allocation descriptor.
[0155] Next, with respect to the space bitmap in the memory section
4, bits corresponding to the logical blocks in which data has been
recorded in Step 405 are changed to "1" representing an "allocated"
state (Step S407). Then, the content of the memory section 4 is
written back to LBN=0 to 250 on the disk 1 (Step S408). Thus, an AV
file is recorded in the directory AV_DIR1.
[0156] In the case of recording a-plurality of AV files
continuously, in the flow chart in FIG. 4, Steps S402 to S407 are
repeated after Step S401 until recording of all the AV files is
completed, and after recording of all the AV files is completed, a
process should proceed to Step S408.
[0157] Because of this, it is not required to write a file
identifier descriptor and a file entry onto a recording medium
every time a file is created, and seeking can be reduced
substantially.
[0158] FIG. 5 shows a data structure in the partition space after
FILE1. DAT and FILE2. DAT that are AV files are recorded in the
directory AV_DIR1 in accordance with the flow chart shown in FIG.
4. Herein, in the AV reservation region, logical blocks are used
for recording new file entries in the decreasing order of LBN. On
the other hand, a file identifier descriptor is added to the end of
the extent (1) that is a recorded extent of the directory AV_DIR1.
Since the file identifier descriptor and the file entry both have a
data structure with a variable length, it is desirable that the
file identifier descriptor is recorded in the increasing order of
LBN in the AV reservation region, and the file entry is recorded in
the decreasing order of LBN.
[0159] In the case where there is an insufficient capacity in the
extent (1) for describing a file identifier descriptor as a result
of addition of a file, the allocation descriptor in the directory
AV_DIR1 is corrected so that a block adjacent to the extent (1) in
the AV reservation region is included in the extent (1), and a file
identifier descriptor should be recorded therein. Addition of a
file entry and a file identifier descriptor with respect to the AV
reservation region is not limited to the above procedure. For
example, it may be possible to divide the AV reservation region
into two, and to use a region with the smaller LBN for recording a
file identifier descriptor and record a file entry from the leading
edge of the remaining region. In this case, the upper limit of the
data length recorded in the file identifier descriptor is
determined previously, for example, by previously determining the
length of a name of a file to be recorded, and the capacity
allocation for dividing the AV reservation region is
determined.
[0160] A recorded AV file is reproduced from the disk shown in FIG.
5 in the following manner. First, in the same way as in Step 401
shown in FIG. 4, the content of LBN=0 to 250 on the disk 1 is read
to the memory section 4. Then, the recorded extent of the directory
AV_DIR1 is scanned to obtain a name of a file present under the
directory AV_DIR1.
[0161] Then, data in the file is accessed by the procedure
described in the prior art to be reproduced. In the case where the
subsequent file is reproduced continuously, the file identifier
descriptors and file entries of all the files present under the
directory AV_DIR1 are read to the memory section 4. Thus, in
reproducing AV files under the directory AV_DIR1, the extents of
the files to be reproduced can be accessed directly, and files can
be reproduced continuously at a high speed without seeking with
respect to a file entry, as occurred according to the conventional
method.
[0162] Such continuous reproduction is realized easily by
performing recording in accordance with the processing procedure
shown in FIG. 4. If the recording procedure of the present
invention is not used, it is unclear in which logical block in the
partition space an entry of an AV file recorded in the directory
AV_DIR1 is recorded. Similarly, the operation of reading data to
the memory section 4 is realized easily at a high speed by
performing recording in accordance with the processing procedure
shown in FIG. 4. If the recording procedure of the present
invention is not used, although it is possible to read data to the
memory section 4, seeking occurs a number of times at the beginning
of a recording/reproduction operation.
[0163] The recording procedure is not limited to the one shown in
FIG. 4. For example, as described in WO 98/14938, the following may
be possible: a plurality of available continuous regions are kept
prior to recording of actual data; these regions are registered in
the space bitmap as "an allocated state"; and thereafter, actual
data start to be recorded.
[0164] Furthermore, information on the allocation descriptor of the
directory AV_DIR1 and the space bitmap may be updated collectively
after recording of file data is completed.
[0165] Furthermore, the data structure in the partition space on a
disk is initialized as shown in FIG. 3 prior to recording of an AV
file, when required.
[0166] A directory/file name in which an AV file is to be recorded
is not limited to that described in Embodiment 1. Another
directory/file name may be used.
[0167] In Embodiment 1, the content of LBN=0 to 250 is read to the
memory section 4 during recording/reproduction. However, all the
information is not required to be kept in the memory section 4.
Only required information may be kept during
recording/reproduction, and only information that needs to be
updated may be written back to the disk 1.
[0168] By keeping LBN=86 to 250 as a "not recorded" but "allocated"
extent of the directory AV_DIR1, LBN=86 to 250 is set to be an AV
reservation region. However, the recorded position and capacity of
the AV reservation region are not limited to LBN=0 to 250. Another
recorded position and capacity may be used as long as they are kept
as continuous regions on the disk.
[0169] In Embodiment 1, the case using a file entry has been
described. However, an extended file entry may be used. In the case
of using an extended file entry, the AV reservation region may be
kept as a part of the extent of a named data stream of the
directory AV_DIR1. In this case, the extent forming the AV
reservation region may be set to be an "allocated" and "recorded"
extent.
Embodiment 2
[0170] Hereinafter, an AV data recording apparatus in Embodiment 2
of the present invention will be described with reference to the
drawings. In Embodiment 1, a file identifier descriptor and a file
entry of an AV file to be newly recorded are recorded in a "not
recorded" but "allocated" extent of the directory AV_DIR1. In
contrast, in Embodiment 2, a management file to store information
for managing an AV file is created under the directory AV_DIR1, and
the management file is allowed to have a "not recorded" but
"allocated" extent.
[0171] FIG. 6 illustrates a file/directory structure immediately
after a directory for recording an AV file is created in the AV
data recording apparatus in Embodiment 2 of the present invention.
The file/directory structure shown in FIG. 6 is different from the
directory structure shown in FIG. 2, in that a management file
(AVFILES.IFO) is present under the directory AV_DIR1.
[0172] FIG. 7 illustrates a data structure in a partition space
when a directory for recording an AV file is recorded. In FIG. 7,
in LBN=0 to 79, a space bitmap descriptor is recorded. Since
LBN=251 to Last is "unallocated", bits corresponding to the sectors
therein are set at "1".
[0173] In LBN=80, a file set descriptor is recorded. When the file
entry therein is that of the root directory, positional information
is recorded in the file set descriptor.
[0174] Furthermore, a terminating descriptor, a file entry of the
root directory, a directory file of the root directory, a file
entry of the directory AV_DIR1, and a file entry of the AVFILES.IFO
file are recorded in LBN=81, LBN=82, LBN=83, LBN=84, and LBN=85,
respectively.
[0175] LBN=86 is an extent in which a directory file of the
directory AV_DIR1 is recorded. LBN=87 to 250 is an extent of the
AVFILES.IFO file. The value of the 2 most significant bits of an
allocation descriptor is set so that the extent is "not recorded"
but "allocated". Thus, this region becomes an AV reservation region
in Embodiment 2.
[0176] When an AV file is recorded on a disk having the
above-mentioned data structure, a processing procedure similar to
that shown in FIG. 4 can be performed. However, the processing
procedure in Embodiment 2 is different from that in Embodiment 1,
in that the AV reservation region for recording a new file
identifier descriptor and a file entry is a "not recorded" but
"allocated" extent of AVFILES.IFO, which is a management file.
[0177] When an AV file is reproduced from a disk, a procedure
similar to that described in Embodiment 1 can be performed. In
Embodiment 2, no data is recorded in the AVFILES.IFO file in an
initial state; however, it may be possible that attribute
information and the like on the directory AV_DIR1 are recorded in
an initial state, and the AVFILES.IFO file is allowed to have an
"allocated" and "recorded" extent, as well as a "not recorded" but
"allocated" extent. Furthermore, the "allocated" and "recorded"
extent may be set to be an AV reservation region.
[0178] In Embodiment 2, the case using a file entry has been
described. However, an extended file entry may be used. In the case
of using an extended file entry, the AV reservation region may be
kept as a part of an extent of a named data stream of the file
AVFILES.IFO. Furthermore, in this case, the extent forming the AV
reservation region may be set to be an "allocated" and "recorded"
extent.
[0179] In Embodiment 2, the AV reservation region management file
is recorded in the same directory as that for recording an AV file.
However, the AV reservation region management file may be recorded
in another directory. By recording the AV reservation region
management file in another directory, it becomes possible to
prevent the management file from being deleted mistakenly by a
user's operation or the like.
Embodiment 3
[0180] Hereinafter, an AV data recording apparatus in Embodiment 3
of the present invention will be described with reference to the
drawings. In Embodiment 3, the case will be described where 100 AV
files are recorded in the directory AV_DIR1. FIG. 8 illustrates a
file/directory structure in Embodiment 3.
[0181] In Embodiments 1 and 2, a "not recorded" but "allocated"
extent is allocated to a directory or a file, and a file entry or
the like of an AV file is recorded in the extent. Embodiment 3 is
different from Embodiments 1 and 2, in that when a directory for
recording an AV file is created, a file identifier descriptor and a
file entry for an AV file also are created in a continuous
region.
[0182] FIG. 9 illustrates a data structure in a partition space in
Embodiment 3. In FIG. 9, each file is assigned a file name
automatically, and these file names are recorded in the file
identifier descriptor. In Embodiment 3, 100 files are present under
the directory AV_DIR1, so that 100 file identifier descriptors are
recorded in the extent of the directory AV_DIR1. An allocation
descriptor in each file entry of the AV files recorded in LBN=101
to 200 does not refer to an extent, and the data capacity as a file
is 0.
[0183] In Embodiment 3, a file identifier descriptor and a file
entry already have been recorded. Therefore, when an AV file is
recorded, data are read to the memory section 4 in the same way as
in the processing procedure shown in FIG. 4. However, at Step S402,
a non-recorded region is not scanned; instead, information on file
entries recorded in LBN=101 to 200 is scanned, a file entry with a
file capacity of 0 is detected, and data are recorded using the
detected file entry as a new AV file.
[0184] When recording of data is completed, information on the
position and length of the extent recorded in the allocation
descriptor of the file entry in the memory section 4 and other file
management information are updated. Finally, the content of the
memory section 4 is written back to the disk 1 in the same way as
in Step S408. Similarly, when an AV file is reproduced, the
procedure similar to that described in Embodiment 1 can be
performed.
[0185] In Embodiment 3, a file entry with a file capacity of 0 is
detected, and data are recorded using the detected file entry as a
new AV file. However, a method for detecting a new file entry is
not limited to this method. Another method may be used. For
example, a file name in an initial state may be changed after
recording of actual AV data. Alternatively, it may be possible to
determined whether or not AV data can be recorded, using a file
attribute field in a file identifier descriptor, an extended
attribute field in the file entry, and the like.
[0186] Furthermore, the data capacity of a file in an initial state
is set to be 0. However, by recording common attribute information
between AV files and the like, data may be recorded even in an
initial state.
Embodiment 4
[0187] Hereinafter, an AV data recording apparatus in Embodiment 4
of the present invention will be described with reference to the
drawings. As described above, in Embodiments 1 to 3, file
management information such as a file entry is recorded in a region
that already has been kept. In Embodiment 4, attribute information
of an AV file, as well as a file entry are recorded in a region
that has already been kept. Because of this, particular information
on an AV file can be accessed continuously at a high speed.
[0188] FIG. 10 illustrates a data structure of an AV file to be
recorded in Embodiment 4. In FIG. 10, an AV file in Embodiment 4 is
a transport stream based on the MPEG system, and is composed of an
AV stream part that is a video stream and an attribute information
part that is a private stream. The AV stream part is composed of a
plurality of video object units (hereinafter, referred to as
"VOBU").
[0189] One VOBU is AV data corresponding to 0.4 to 1 second of
video data, and includes a video data interval called a GOP (Group
of Picture) under the MPEG2 standard. The GOP includes at least one
I-picture, so that the GOP can be reproduced independently. In the
case of special reproduction such as fast-forward reproduction and
fast-backward reproduction and reproduction at a specified time, an
I-picture in the GOP is extracted as an image to be reproduced.
[0190] In the attribute information part, attribute information on
an AV stream is recorded. For example, a recorded date and time of
a file, a comment with respect to recorded information, parameters
during recording, a thumbnail image, and the like are recorded.
Furthermore, in the attribute information part, in addition to the
above-mentioned attribute information, time map information is
recorded for the purpose of facilitating special reproduction such
as fast-forward reproduction and reproduction at a specified time
with respect to an AV stream.
[0191] The time map information is the one in which a reproduction
time of an AV stream is related to a recorded position, for
example, as described in JP 3028517. As shown in FIG. 11, the time
map information has a hierarchical data structure composed of two
tables called a time map table and a VOBU table.
[0192] In the time map table, time maps #1, #2, . . . are arranged.
Time maps #1, #2, . . . represent recorded positions of VOBU
corresponding to reproduction times in the case where data is
reproduced at a predetermined time interval TMU (e.g., 60 seconds)
on a time axis with a leading edge of the AV stream part at a
starting time.
[0193] In the VOBU table, VOBU maps, each containing a reproduction
time and a data size of each VOBU, are arranged in the order of
reproduction time from the leading edge of the AV stream part.
[0194] FIG. 12 shows the data structure of time map information in
more detail. FIG. 13 shows the logical link relationship between
the time map table and the VOBU table.
[0195] Herein, time map general information includes the number of
time maps and VOBU maps included in the time map information, a
time unit (hereinafter, referred to as "TMU") representing a
predetermined time interval in which time maps are provided, and a
time offset (hereinafter, referred to as "TM_OFS") representing a
time difference between the leading time of the AV stream part and
the time of the leading time map. The value of TM_OFS is "0", as
long as an edit operation such as deletion of the leading edge of
the AV stream part is performed.
[0196] In the time map table, a plurality of time maps #1, #2, . .
. are provided at a predetermined time interval represented by the
TMU and arranged in the order of time.
[0197] Each time map is composed of a VOBU map number, a time
difference (hereinafter, referred to as "TM_DIFF"), and a VOBU
address (hereinafter, referred to as "VOBU_ADR"). VOBU_ADR is
positional information in the AV stream part at the leading edge of
the corresponding VOBU.
[0198] A reproduction time (hereinafter, referred to as a "time map
time") with respect to time map #i is represented by Formula
(1).
(Time map time)=(TMU*(i-1)+TM.sub.--OFS) (1)
[0199] The VOBU map number represents the number present at a
reproduction time represented by Formula (1). For example, as shown
in FIG. 13, the time map #1 represents a time obtained by adding
TM_OFS to a leading time in the AV stream part. The time map #2
represents a time after TMU from the time map #1. Thereafter, the
time maps represent VOBU maps present at reproduction times at 2
TMU, 3 TMU, . . . , respectively.
[0200] TM_DIFF represents a time difference between the leading
time of the corresponding VOBU and the time map time. Thus, the
leading time of VOBU #j is represented by Formula (2).
(Leading time of VOBU)=TMU*(j-1)+TM.sub.--OFS-TM.sub.--TIFF (2)
[0201] In the VOBU table, VOBU maps #1, #2, . . . corresponding to
VOBUs contained in the AV stream part in one-to-one relationship.
Each VOBU map consists of a reference image size, a VOBU
reproduction time, and a VOBU size.
[0202] The reference image size refers to the size of the first
I-picture in the VOBU, and is used for finding an image of interest
for special reproduction or reproduction at a specified time. For
example, by adding successively a VOBU reproduction time to the
VOBU leading time until the reproduction time of an image of
interest is obtained, a VOBU to be reproduced is specified and an
image in the VOBU is specified.
[0203] A VOBU size is a data size of a VOBU, and is used for
specifying the position of image data of interest for special
reproduction or reproduction at a specified time.
[0204] As described above, in Embodiment 4, even in the case of
special reproduction, a particular image such as an I-picture can
be searched for at a high speed.
[0205] A file/directory structure in an initial state in Embodiment
4 is the same as that shown in FIG. 2. FIG. 14 shows a data
structure in a partition space in this case. The data structure in
FIG. 14 is different from that in FIG. 3, in that a region for
recording a part of an AV file in addition to file management
information also is kept as a "not recorded" but "allocated" extent
of the directory AV_DIR1. Therefore, the extent (2) of the
directory AV_DIR1 is recorded in logical blocks LBN=86 to 500. In
the case of the same number of AV files, the data structure shown
in FIG. 14 can keep more AV files, compared with that shown in FIG.
3. In this case, the capacity to be kept equals the total of the
capacity of file management information and the capacity of
attribute information part with respect to the assumed number of AV
files.
[0206] Regarding an AV file, an item (i.e., time map information)
that is varied depending upon the data capacity in the AV stream
part is included in the attribute information part. However, by
setting conditions such as a disk capacity, the number of AV files
to be recorded, and a bit rate of an AV stream, the maximum
capacity in the time map information part to be recorded on the
disk 1 can be determined previously. Thus, the capacity of an AV
reservation region should be kept with respect to an AV file to be
recorded in the directory AV_DIR1, expecting the total capacity in
the attribute information part in the case where the capacity of
the time map information part becomes maximized.
[0207] An AV file is recorded onto a disk having the
above-mentioned data structure in accordance with a flow chart
shown in FIG. 15.
[0208] In FIG. 15, first, the content of LBN=0 to 500 on the disk 1
is read to the memory section 4 (Step S1301). Then, extent
information in the directory AV_DIR1 in the memory section 4 is
scanned to determine whether or not there is a non-recorded region
sufficient for recording a file identifier descriptor, a file
entry, and an attribute information part of a file (Step S1302).
When it is determined that there is not a sufficient non-recorded
region (Step S1302: No), error processing is performed and
recording of an AV file is ended. When it is determined that there
is a sufficient non-recorded region, a file identifier descriptor,
a file entry, and an attribute information part of an AV file are
recorded in the non-recorded region in the extent of the directory
AV_DIR1 in the memory section 4 (Step S1303).
[0209] Then, in accordance with recording of the file identifier
descriptor, the file entry, and the attribute information part of
an AV file, an allocation descriptor of the file entry of the
directory AV_DIR1 is rewritten. More specifically, the extent
length of the recorded extent is changed by addition of the file
identifier descriptor, and a portion in which the file entry has
been recorded is excluded from the non-recorded extent.
Furthermore, information that is determined to be recorded in the
attribute information part of an AV file also is recorded in the AV
reservation region in the memory section 4.
[0210] Next, the space bitmap in the memory section 4 is scanned to
determine whether or not there are the required number of
unallocated logical blocks for recording an AV file (Step S1304).
When it is determined that there are no the required number of
unallocated logical blocks (Step S1304: No), error processing is
performed, and recording of an AV file is ended. When it is
determined that there are the required number of unallocated
logical blocks, data is recorded in a logical block on a recording
medium corresponding to the non-recorded region obtained in Step
S1303 (Step S1305).
[0211] Furthermore, time map information is obtained at this time
among attribute information of an AV file, so that it is recorded
appropriately in the AV reservation region in the memory section 4.
When recording of the AV file data is completed, information on the
position and length of an extent of the AV file are recorded in an
allocation descriptor in the file entry created in Step S1303 (Step
S1306). Furthermore, required information such as a file name and a
file creation time are updated with respect to the file identifier
descriptor and the file entry, in addition to the allocation
descriptor.
[0212] Next, with respect to the space bit map in the memory
section 4, a bit corresponding to the logical block in which data
has been recorded in Step S1305 is changed to "1" representing an
"allocated" state (Step S1307). Then, the content of the memory
section 4 is written back to LBN=0 to 500 (Step S1308). Thus, an AV
file is recorded in the directory AV_DIR1.
[0213] In the case of recording a plurality of AV files
continuously, in the flow chart in FIG. 15, Steps S1302 to S1307
are repeated after Step S1301 until recording of all the AV files
is completed, and after recording of all the AV files is completed,
a process should proceed to Step S1308. Because of this, it is not
required to write a file identifier descriptor and a file entry
onto a disk every time a file is created, and seeking can be
reduced substantially.
[0214] FIG. 16 shows a data structure in the partition space after
FILE 1. DAT and FILE2. DAT that are AV files are recorded in the
directory AV_DIR1 in accordance with the flow chart shown in FIG.
15. Herein, in the AV reservation region, a file identifier
descriptor, a file entry, and an attribute information part of an
AV file are recorded.
[0215] An AV file is reproduced from a disk having the data
structure as shown in FIG. 16 by the procedure similar to that
described in Embodiment 1. In Step S408, the content of LBN=0 to
500 on the disk 1 is read to the memory section 4.
[0216] Furthermore, in the case of reproducing a particular display
time of an AV file, file identifier descriptors, file entries, and
attribute information parts including time map information of all
the AV files present under the directory AV_DIR1 are read to the
memory section 4. Thus, an offset position in a file with respect
to a certain reproduction time is obtained by processing only
information in the memory section 4, and seeking is not required
with respect to the disk 1. As a result, special reproduction
(selective reproduction of particular frames) can be performed
easily. Furthermore, it becomes possible that various pieces of
attribute information are extracted, and a list thereof is
displayed to a user.
[0217] Such continuous reproduction is realized easily by
performing recording in accordance with the processing procedure
shown in FIG. 15. If the recording procedure in Embodiment 4 is not
used, attribute information of an AV file is recorded in the same
extent as that in the AV stream part, and distributed on the disk.
As a result, seeking to extract attribute information cannot be
avoided.
[0218] The positional relationship in the AV reservation region of
a file entry, attribute information, and time map information may
be varied. In the course of reproduction of an AV file, a portion
of the AV reservation region, in which attribute information of an
AV file is recorded, is read entirely to the memory section 4.
However, instead of reading the entire portion from the beginning,
the attribute information may be read when required. In this case,
compared with the prior art, seeking can be reduced, and a table
for attribute information of an AV file and a high-speed access can
be read at a high speed.
[0219] Furthermore, in Embodiment 4, the AV reservation region is
provided as an extent of the directory AV_DIR1. However, it may be
possible to create a management file, and provide an AV reservation
region as the extent of the management file as in Embodiment 2. In
this case, recording/reproduction of an AV file is performed in the
same way as in Embodiment 2.
[0220] The AV reservation region may be kept as a plurality of
extents. For example, it may be possible to provide an AV
reservation region for a file management region as an extent of the
directory AV_DIR1, and to provide an AV reservation region for
attribute information of an AV file as an extent of the management
file.
[0221] Alternatively, the following may be possible: two kinds of
management files are provided, an AV reservation region for a file
management region is provided in the first management file, and an
AV reservation region for attribute information of an AV file is
provided in the second management file. Furthermore, other methods
may be used, as long as an AV reservation region is kept as a
continuous region.
[0222] Time map information should be the one in which a
reproduction time of an AV stream is related to a recorded
position, and may have a structure other than that shown in FIG.
11.
[0223] In Embodiment 4, an AV file is a transport stream based on
the MPEG. However, the AV file may be in another format. Particular
information of an AV file simply may be recorded in a region that
has been kept previously.
Embodiment 5
[0224] Hereinafter, an AV data recording apparatus in Embodiment 5
of the present invention will be described with reference to the
drawings. As described above, in Embodiment 4, an AV file is
recorded, which is composed of an AV stream part in which video
data of MPEG2 is recorded and an attribute information part. In
Embodiment 5, an AV file is an Exif image file, which is composed
of an Exif main image (main image data), and additional information
related to the Exif main image.
[0225] More specifically, an AV file in Embodiment 5 is composed of
a header part formed of additional information related to a still
image and a video data part formed of a still image data body. The
additional information is recorded in an AV reservation region.
Because of this, particular information such as a thumbnail image
of an AV file can be accessed continuously at a high speed, by
seeking only in the AV reservation region.
[0226] FIG. 17 illustrates a data structure of an AV file in the AV
data recording apparatus in Embodiment 5 of the present invention.
In FIG. 17, an AV file in Embodiment 5 is composed of a header part
and a video data part.
[0227] In the header part, additional information on the image data
part is recorded. For example, a recorded date and time of a file,
a comment on recorded information, parameters at a time of
recording/compression, a thumbnail image, and the like are
recorded. Furthermore, in the video data part, a still image data
body compressed based on the JPEG system is recorded.
[0228] A file/directory structure in the AV data recording
apparatus in Embodiment 5 is the same as that shown in FIG. 2. A
data structure in a partition space thereof is the same as that
shown in FIG. 14.
[0229] In the AV reservation region, file management information of
an AV file, and data with a predetermined capacity from the leading
edge of the AV file are recorded. It is assumed that data with such
a predetermined capacity include at least a thumbnail image in the
header part of an AV file.
[0230] Thus, when a thumbnail list of recorded AV files and a list
of recorded date and time are displayed to a user, information
thereof is recorded in the AV reservation region that is a
continuous region, so that they can be displayed at a high
speed.
[0231] A data structure of an AV file may be constructed as shown
in FIG. 18: padding data are inserted into the header part so that
the capacity of the entire header part is adjusted to be an
integral multiple of the logical block capacity of the UDF. At this
time, since the capacity of the header part is an integral multiple
of the logical block capacity of the UDF, the video data part
always is positioned from the leading edge of the logical block.
Furthermore, only the file management information and the header
part are recorded in the AV reservation region. Thus, in the course
of recording/reproduction of an AV file, the header part can be
separated completely from the video data part, and data can be
processed on a logical block basis; therefore,
recording/reproduction can be performed at a higher speed.
[0232] In Embodiment 5, as an AV file, an Exif file containing a
main image compressed based on the JPEG system is used. However,
the present invention is not limited thereto. Any still image file
with a format having additional information in the header part may
be used.
[0233] A plurality of AV directories may be present on the disk. In
this case, a still image file is recorded in one directory as in
Embodiment 5, and a video file of MPEG2 may be recorded in the
other directory as in Embodiment 4. Furthermore, the number of AV
directories is not limited to two. If required, the number of
directories may be increased.
[0234] In this case, the AV reservation region may be managed on a
directory basis. Alternatively, it may be possible to provide a
dedicated management directory and manage an AV reservation region
used in each directory. For example, as shown in FIG. 19, the
following is conceivable: an AV reservation region management file
AVFILES.IFO is placed under a management directory AV_INFO, a still
image file is recorded in the AV directory AV_DIR1 using an AV
reservation region managed by the AV reservation region management
file, and a video file is recorded in the directory AV_DIR2.
[0235] A video file and a still image file are not required to be
recorded in separate directories. A video file and a still image
file may be mixed in one directory.
[0236] As described above, in Embodiment 5, data recorded by a user
can be separated from information for managing the data, which
prevents damage and the like to management information due to
maloperation and the like. In Embodiment 5, a single AV reservation
management region file is used. However, for example, an AV
reservation management region file may be provided on an AV
directory basis.
Embodiment 6
[0237] Hereinafter, an AV data recording apparatus in Embodiment 6
of the present invention will be described with reference to the
drawings. In Embodiment 6, the case will be described where an AV
directory has a hierarchical structure. It is convenient to support
a hierarchical directory for classifying recorded data, and the
like. However, in the case of the UDF, a directory also is handled
as a kind of a file, so that seeking cannot be avoided particularly
in the case of a directory structure with a deep hierarchy.
[0238] In Embodiment 6, a reservation region is provided for
creating a hierarchical directory. FIG. 20 illustrates a
file/directory structure immediately after a directory for
recording an AV file is created.
[0239] FIG. 21 shows a data structure in a partition space when the
file/directory structure shown in FIG. 20 is recorded on a disk
used in the AV data recording apparatus in Embodiment 6 of the
present invention.
[0240] LBN=86 to 250 is an extent (2) of the AV_DIR1 directory, and
the value of the 2 most significant bits of an allocation
descriptor is set so that the extent (2) is "not recorded" but
"allocated". Hereinafter, the extent (2) will be referred to as an
AV directory reservation region.
[0241] A subdirectory is created under the AV directory on the disk
having the above-mentioned structure in accordance with a flow
chart shown in FIG. 22.
[0242] First, the content of LBN=0 to 250 on the disk 1 is read to
the memory section 4 (Step S171). Then, information in the AV
directory reservation region in the memory section 4 is scanned to
determine whether or not there is a non-recorded region sufficient
for newly recording a file identifier descriptor and a file entry
for the AV subdirectory (Step S172). When it is determined that
there is not a sufficient non-recorded region (Step S172: No),
error processing is performed, and creation of an AV subdirectory
is ended.
[0243] When it is determined that there is a sufficient
non-recorded region, a file identifier descriptor and a file entry
are recorded in the non-recorded region in the AV reservation
region in the memory section 4 (Step S173). At this time, the size
of the extent of the AV_DIR1 directory is changed due to recording
of the file identifier descriptor and the file entry; therefore, an
allocation descriptor of the file entry of the AV_DIR1 directory is
rewritten in accordance with the change.
[0244] More specifically, the extent length of the extent (1) is
changed by addition of the file identifier descriptor, and a
portion in which the file entry has been recorded is excluded from
the extent (2).
[0245] Next, the space bitmap in the memory section 4 is scanned to
determine whether or not there are the required number of
continuous unallocated logical blocks for recording an AV
subdirectory and an AV reservation region to be allocated thereto
(Step S174). When it is determined that there are not the required
number of continuous unallocated logical blocks (Step S174: No),
processing is ended.
[0246] When it is determined that there are the required number of
continuous unallocated logical blocks, data are recorded in a
logical block on the disk corresponding to an unallocated region
obtained in Step S173 (Step S175). Herein, recording of data
includes creation of a directory file of an AV subdirectory, and
keeping of an AV reservation region allocated to the AV
subdirectory.
[0247] When recording of data is completed, in order to update file
management information of the AV subdirectory file, information on
the position and length of the extent of the AV subdirectory file
is recorded in an allocation descriptor of the file entry in the
memory section 4 created in Step S173 (Step S176).
[0248] Furthermore, required information such as a file name and a
file creation time also are updated with respect to the file
identifier descriptor and the file entry, in addition to the
allocation descriptor.
[0249] Next, with respect to the space bitmap in the memory section
4, bits corresponding to logical blocks in which data is recorded
in Step S173 are changed to "1" representing an "allocated" state
(Step S177).
[0250] Then, the content of the memory section 4 is written back to
LBN=0 to 250 (Step S178). Thus, an AV subdirectory AV_SUB_DIR1 is
created under the directory AV_DIR1 by a series of processing. FIG.
23 shows a directory structure in this case. FIG. 24 shows a data
structure in the partition space in this case.
[0251] Herein, in the same way as in Embodiment 1, new file entries
are recorded in logical blocks in the decreasing order of LBN in
the AV directory reservation region. On the other hand, the file
identifier descriptor is added to the end of the extent (1) that is
a recorded extent of the directory AV_DIR1. Herein, an AV file is
not recorded, and a directory file is recorded.
[0252] The created AV subdirectory is an extent (2), and the value
of the 2. most significant bits of an allocation descriptor is set
so that the extent (2) is "not recorded" but "allocated". When an
AV file is recorded in the directory AV_SUB_DIR1 hereinafter, it is
recorded in the same procedure as that in Embodiment 1, using the
AV reservation region.
[0253] Furthermore, an AV file is recorded on the disk having the
above-mentioned data structure in accordance with a flow chart in
FIG. 25.
[0254] First, the contents of LBN=0 to 79 and LBN=250 to 400 on the
disk 1 are read to the memory section 4 (Step S201). Then,
information in the AV reservation region in the subdirectory
AV_SUB_DIR1 in the memory section 4 is scanned to determine whether
or not there is a non-recorded region sufficient for newly
recording a file identifier descriptor and a file entry (Step
S202). When it is determined that there is not a sufficient
non-recorded region (Step S202: No), error processing is performed,
and recording of an AV file is ended.
[0255] When it is determined that there is a sufficient
non-recorded region, a file identifier descriptor and a file entry
are recorded in a non-recorded region in the AV reservation region
in the subdirectory AV_SUB_DIR1 in the memory section 4 (Step
S203).
[0256] Then, the space bitmap in the memory section 4 is scanned to
determine whether or not there are the required number of
unallocated logical blocks for recording AV files (Step S204). When
it is determined that there are not the required number of
unallocated logical blocks (Step S204: No), error processing is
performed, and recording is completed.
[0257] When it is determined that there are the required number of
unallocated logical blocks, data is recorded in a logical block on
a recording medium corresponding to the non-recorded region
obtained in Step S203 (Step S205).
[0258] When recording of AV file data is completed, in order to
update the file management information of the AV file, information
on the position and length of the extent of the AV file is recorded
in an allocation descriptor of the file entry in the memory section
4 created in Step S205 (Step S206).
[0259] Next, with respect to the space bitmap in the memory section
4, bits corresponding to logical blocks in which data are recorded
in Step S205 are changed to "1" representing an "allocated" state
(Step S207).
[0260] Then, the content of the memory section 4 is written back to
LBN=0 to 79 and LBN=250 to 400 on the disk 1 (Step S208). Thus, an
AV file can be recorded in the directory AV_SUB_DIR1.
[0261] FIG. 26 shows a data structure in a partition space after
FILE1.DAT and FILE2.DAT that are AV files are recorded in the
directory AV SUB_DIR1 by processing shown in FIG. 25.
[0262] In FIG. 26, in the AV reservation region allocated to the
directory AV_SUB_DIR1, logical blocks are used in the decreasing
order of LBN for recording new file entries. On the other hand, a
file identifier descriptor is added to the end of the extent (1)
that is a recorded extent of the directory AV_SUB_DIR1. In the case
where a predetermined number of AV files are recorded in the
directory AV_SUB_DIR1, another subdirectory is created under the
directory AV_DIR1, and an AV file is recorded in this
directory.
[0263] An AV file is reproduced from a disk having the data
structure shown in FIG. 26 by the following procedure. First, a
root directory is read, and the directory AV_DIR1 and the directory
AV_SUB_DIR1 are read. At this time, a portion corresponding to the
AV reservation region allocated to the directory AV_SUB_DIR1 (i.e.,
LBN=251 to 400) is read to the memory section 4.
[0264] Then, the recorded extent of the directory AV_SUB_DIR1 is
scanned to obtain a name of a file in the directory
AV_SUB_DIR1.
[0265] Next, data in the file is accessed and reproduced in the
procedure described in the prior art.
[0266] In the case where a file in another AV subdirectory is read,
an AV reservation region allocated to the AV subdirectory is read,
and thereafter, a file is accessed.
[0267] As described above, in Embodiment 6, even in the case where
a directory has a hierarchical structure, seeking at a time of
creating a file and reading a file can be reduced
substantially.
[0268] A new AV subdirectory should be created, for example, in the
case of a user's instruction, or in the case where a predetermined
number of files are recorded in the AV subdirectory.
Embodiment 7
[0269] Hereinafter, an AV data recording apparatus in Embodiment 7
of the present invention will be described with reference to the
drawings. In Embodiment 7, the case will be described where an AV
reservation region also is allocated to an AV subdirectory when the
AV directory has a hierarchical structure.
[0270] First, in Embodiment 7, a file/directory structure
immediately after a directory for recording an AV directory is
created is the same as that shown in FIG. 20. Furthermore, a data
structure in a partition space is the same as that shown in FIG.
21. FIG. 27 is a flow chart showing processing in the case where a
subdirectory is created under an AV directory on a disk having the
above-mentioned data structure.
[0271] In FIG. 27, the content of LBN=0 to 250 on the disk 1 is
read to the memory section 4 (Step S241). Then, information in an
AV directory reservation region in the memory section 4 is scanned
to determine whether or not there is a non-recorded region
sufficient for newly recording a file identifier descriptor and a
file entry for an AV subdirectory (Step S242).
[0272] When it is determined that there is not a sufficient
non-recorded region (Step S242: No), error processing is performed,
and creation of an AV subdirectory is ended. When it is determined
that there is a sufficient non-recorded region (Step S242: Yes), a
file identifier descriptor, a file entry, and an AV subdirectory
file are recorded in a non-recorded region in the AV reservation
region in the memory section 4 (Step S243).
[0273] When a file identifier descriptor, a file entry, and an AV
subdirectory file are recorded, the size of the extent of the
AV_DIR1 directory is changed. Therefore, an allocation descriptor
of the file entry of the AV_DIR1 directory is rewritten in
accordance with the change. More specifically, the extent length of
the extent (1) is changed by addition of the file identifier
descriptor, and a portion in which the file entry and the directory
file are recorded is excluded from the extent (2).
[0274] Next, information on a space bitmap in the memory section 4
is updated if required (Step S244). The content of the memory
section 4 is written back to LBN=0 to 250 on the disk 1 (Step
S245).
[0275] An AV subdirectory AV SUB_DIR1 is created under the
directory AV_DIR1 by the above-mentioned series of processing. A
directory structure after creation of an AV subdirectory is the
same as that shown in FIG. 23.
[0276] FIG. 28 shows a partition structure after creation of an AV
subdirectory. In FIG. 28, in the same way as in Embodiment 1, a
file identifier descriptor is recorded so as to be added to the end
of the extent (1) that is a recorded extent of the subdirectory
AV_SUB_DIR1. On the other hand, for recording a new file entry and
a directory file, logical blocks are used in decreasing order of
LBN in the AV directory reservation region.
[0277] Next, FIG. 29 is a flow chart showing processing for
recording an AV file on a disk having the above-mentioned data
structure. In FIG. 29, the content of LBN=0 to 250 on the disk 1 is
read to the memory section 4 (Step S261), and information in an AV
directory reservation region in the memory section 4 is scanned to
determine whether or not there is a non-recorded region sufficient
for newly recording a file identifier descriptor and a file entry
(Step S262).
[0278] When it is determined that there is not a sufficient
non-recorded region (Step S262: No), error processing is performed,
and recording of an AV file is ended. When it is determined that
there is a sufficient non-recorded region (Step S262: Yes), a file
identifier descriptor and a file entry are recorded in a
non-recorded region in the AV reservation region in the memory
section 4 (Step S263).
[0279] Next, the space bitmap in the memory section 4 is scanned to
determine whether or not there are the required number of
unallocated logical blocks for recording an AV file (Step S264).
When it is determined that there are not the required number of
unallocated logical blocks (Step S264: No), error processing is
performed, and recording of an AV file is ended. When it is
determined that there are the required number of unallocated
logical blocks (Step S264: Yes), data are recorded in a logical
block corresponding to the region (Step S265).
[0280] When recording of AV file data is completed, in order to
update file management information of the AV file, information on
the position and length of the extent of the AV file is recorded in
an allocation descriptor of the file entry in the memory section 4
created in Step S263 (Step S266).
[0281] Next, with respect to the space bitmap in the memory section
4, bits corresponding to logical blocks in which data is recorded
in Step S265 are changed to "1" representing an "allocated" state
(Step S267). Then, the content of the memory section 4 is written
back to LBN=0 to 250 on the disk 1 (Step S268). Thus, an AV file
can be recorded in the subdirectory AV_SUB_DIR1.
[0282] FIG. 30 shows a structure in a partition space after an AV
file FILE1.DAT is recorded in the AV subdirectory AV_SUB_DIR1, and
a new subdirectory AV_SUB_DIR2 is created. In FIG. 30, in an AV
reservation region in the directory AV_DIR1, an AV subdirectory,
file management information of an AV file recorded in the AV
subdirectory, and an AV subdirectory file are recorded. Because of
this structure, even in the case where files in different AV
subdirectories are accessed continuously, seeking with respect to
the disk can be reduced. FIG. 31 shows a directory structure in
this case.
[0283] When an AV file is reproduced from a disk having the
above-mentioned data structure, a root directory is read, and a
directory AV_DIR1 is read. At this time, a region containing a
portion corresponding to an AV reservation region allocated to the
directory AV_DIR1 (i.e., LBN=0 to 250) is read to the memory
section 4.
[0284] Then, an extent of the subdirectory AV_SUB_DIR1 in the
memory section 1 is scanned to obtain a name of a file recorded in
the subdirectory AV SUB_DIR1.
[0285] Even in the case where a file in another AV subdirectory is
read, since the extent of the directory file has already been read
to the memory section 4, an intended file can be accessed by
scanning such information.
[0286] As described above, in Embodiment 7, even in the case where
a directory has a hierarchical structure, seeking during
creation/reading of a file can be reduced substantially.
Embodiment 8
[0287] For the purpose of performing real-time recording, an AV
file is often recorded, skipping a defective block without
conducting replacement processing, as described in WO 98/14938.
[0288] On the other hand, when file management information recorded
in an AV reservation region cannot be read due to a defect of a
disk or the like, reproduction of a file becomes impossible;
therefore, recording with high reliability is required.
[0289] According to an AV data recording method in Embodiment 8,
when a directory for recording an AV file is created, and an AV
reservation region is kept, a defective block is examined. When a
defective block is found, the subsequent block is used instead of
the defective block, and an AV reservation region is kept.
[0290] Because of the above, continuity of data to be recorded in
the AV reservation region is not impaired, and recording can be
performed with high reliability.
Embodiment 9
[0291] In the case where an AV file has a thumbnail image as a
separate file, a continuous region for recording the thumbnail
image is kept as a reservation region.
[0292] Since the thumbnail image is recorded in the continuous
region, a thumbnail list of a recorded file can be displayed to a
user at a high speed.
Embodiment 10
[0293] In the above-mentioned embodiments, when a new AV file is
recorded, it is determined whether or not there is a non-recorded
region in an AV reservation region; when it is determined that
there is not a sufficient non-recorded region for recording a new
AV file, error processing is performed, and recording of an AV file
is ended.
[0294] However, according to the above-mentioned processing, even
when a disk capacity remains, if a non-recorded region is used up
in an AV reservation region, an AV file cannot be recorded therein
any more.
[0295] In Embodiment 10, in the case where an AV reservation region
has an insufficient capacity, a new AV reservation region is kept,
and thereafter, an AV file is recorded.
[0296] FIG. 32 shows a partition space when there is no
non-recorded region in an AV reservation region due to recording of
an AV file. In this case, a plurality of AV files are recorded in
LBN=251 to 685. In LBN=86 to 250 that is an AV reservation region,
file management information and the like of file entries with
respect to the AV files are recorded. Thus, even if it is attempted
to record a new AV file, the AV reservation region has no
non-recorded region, so that an AV file cannot be recorded.
[0297] A new AV reservation region is kept as a "not recorded" but
"allocated" extent of the directory AV_DIR1. Processing for keeping
a new AV reservation region is performed in the procedure shown in
FIG. 33.
[0298] In FIG. 33, first, information on the space bitmap is
scanned to determine whether or not there are the required number
of continuous unallocated logical blocks for keeping a new AV
reservation region (Step S331). When it is determined that there
are not the required number of logical blocks (Step S331: No),
error processing is performed, and an operation of keeping an AV
reservation region is ended (Step S332).
[0299] When it is determined that there are the required number of
logical blocks (Step S331: Yes), the unallocated region is kept as
a "not recorded" but "allocated" extent (3) of the directory
AV_DIR1. More specifically, information on the position and length
of the extent (3) is recorded in an allocation descriptor in the
file entry of the directory AV_DIR1 (Step S333).
[0300] Next, with respect to the space bitmap in the memory section
4, bits corresponding to logical blocks of the extent (3) are
changed to "1"representing an "allocated" state (Step S334).
[0301] FIG. 34 shows a state of a partition space after a new AV
reservation region is kept. In FIG. 34, LBN=686 to 850 is kept as a
new AV reservation region.
[0302] The processing procedure for keeping a new AV reservation
region is not limited to the above-mentioned order. For example,
the following may be possible: after it is determined whether or
not there are the required number of logical blocks, information on
the space bitmap is changed; thereafter, information on the extent
(3) is recorded in an allocation descriptor in the file entry of
the directory AV_DIR1.
[0303] Furthermore, as described in Embodiment 2, in the case where
the AV reservation region is kept as an extent of a management file
AVFILES.IFO, a new AV reservation region should be kept as an
extent of the management file AVFILES.IFO.
[0304] Furthermore, in the case where an AV reservation region is
kept as a named stream, the new AV reservation region may be kept
as a named stream.
[0305] As described above, in the AV data recording apparatus of
the present invention, by recording file management information and
attribute information of an AV file in a continuous region that has
been kept previously, seeking with respect to a disk, which
prevents real-time recording/reproduction of an AV file, can be
reduced.
[0306] Furthermore, even in the case where a large number of still
images of JPEG compression are recorded, since the file management
region is recorded in a continuous region, the still images can be
read at a high speed.
[0307] The invention may be embodied in other forms without
departing from the spirit or essential characteristics thereof The
embodiments disclosed in this application are to be considered in
all respects as illustrative and not limiting. The scope of the
invention is indicated by the appended claims rather than by the
foregoing description, and all changes which come within the
meaning and range of equivalency of the claims are intended to be
embraced therein.
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