U.S. patent application number 15/092666 was filed with the patent office on 2016-12-29 for video signal processing device and projection-type display device.
The applicant listed for this patent is JVC KENWOOD Corporation. Invention is credited to Atsushi YOSHIDA.
Application Number | 20160381333 15/092666 |
Document ID | / |
Family ID | 57603119 |
Filed Date | 2016-12-29 |
United States Patent
Application |
20160381333 |
Kind Code |
A1 |
YOSHIDA; Atsushi |
December 29, 2016 |
VIDEO SIGNAL PROCESSING DEVICE AND PROJECTION-TYPE DISPLAY
DEVICE
Abstract
A black stripe detector is configured to detect whether or not
each pixel of an input video signal is a pixel in a black stripe
region, and to generate a black stripe identification signal. A
signal combiner is configured to combine the input video signal and
the black stripe identification signal with each other to generate
a combination signal. A keystone correction processor is configured
to implement keystone correction processing for the combination
signal, and to generate a keystone-corrected video signal. A signal
separator is configured to separate the keystone-corrected
combination signal into a keystone-corrected video signal and a
keystone-corrected black stripe identification signal. A video
signal processor is configured to implement predetermined video
signal processing for the keystone-corrected video signal by using
the keystone-corrected video signal and the keystone-corrected
black stripe signal.
Inventors: |
YOSHIDA; Atsushi;
(Yokohama-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
JVC KENWOOD Corporation |
Yokohama-shi |
|
JP |
|
|
Family ID: |
57603119 |
Appl. No.: |
15/092666 |
Filed: |
April 7, 2016 |
Current U.S.
Class: |
348/746 |
Current CPC
Class: |
H04N 9/3188 20130101;
H04N 9/3194 20130101; H04N 9/3185 20130101 |
International
Class: |
H04N 9/31 20060101
H04N009/31 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 24, 2015 |
JP |
2015-126137 |
Claims
1. A video signal processing device comprising: a black stripe
detector configured to detect whether or not each pixel of an input
video signal, in which a part of an effective region is a black
stripe region, is a pixel included in the black stripe region, and
to generate a black stripe identification signal; a signal combiner
configured to combine the input video signal and the black stripe
identification signal with each other to generate a combination
signal; a keystone correction processor configured to implement
keystone correction processing for the combination signal so as to
correct a trapezoidal distortion when the input video signal is
projected onto a screen, and to generate a keystone-corrected
combination signal; a signal separator configured to separate the
keystone-corrected combination signal into a keystone-corrected
video signal subjected to the keystone correction processing and a
keystone-corrected black stripe identification signal indicating
whether or not each pixel of the keystone-corrected video signal is
a pixel included in a black stripe region; and a video signal
processor configured to implement predetermined video signal
processing for the keystone-corrected video signal by using the
keystone-corrected video signal and the keystone-corrected black
stripe signal.
2. The video signal processing device according to claim 1, further
comprising a video filter processor configured to implement
filtering processing, which uses peripheral pixels for each of
pixels of the input video signal inputted to the signal
combiner.
3. The video signal processing device according to claim 2, further
comprising a black stripe filter processor configured to implement
filtering processing, which uses signals in the same range as the
range of the peripheral pixels for the signal of each pixel unit of
the black stripe identification signal.
4. The video signal processing device according to claim 2, wherein
the video filter processor is a low-pass filter or a median
filter.
5. The video signal processing device according to claim 3, wherein
the black stripe filter processor is a low-pass filter or a median
filter.
6. The video signal processing device according to claim 1, wherein
the video signal processor is a frame rate conversion circuit
configured to convert a frame rate of the keystone-corrected video
signal or an up-conversion circuit configured to increase a
resolution of the keystone-corrected video signal.
7. A projection-type display device comprising: the video signal
processing device according to claim 1; and a projector configured
to project a video signal which is outputted from the video signal
processor onto the screen.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is based upon and claims the benefit of
priority under 35 U.S.C..sctn.119 from Japanese Patent Application
No. 2015-126137, filed on Jun. 24, 2015, the entire contents of
which are incorporated herein by reference.
BACKGROUND
[0002] The present disclosure relates to a video signal processing
device and a projection-type display device.
[0003] As aspect ratios of an effective region of a video signal,
various types are present, which include: 4:3 of the NTSC system;
16:9 of the high vision system; 1.375:1 for use in a movie, and the
like. For example, in order to create a video signal with an aspect
ratio of 16:9 based on a video signal with an aspect ratio of 4:3,
black stripe regions are often added on the right and left sides of
a video region with the aspect ratio of 4:3 to create a video
signal with the aspect ratio of 16:9.
[0004] As described above, when creating a video signal with
another aspect ratio based on a video signal with a certain aspect
ratio, in some cases, the black stripe regions are added to the
upper and lower or right and left sides of the video region, and
the video signal with another aspect ratio is created.
SUMMARY
[0005] Incidentally, when displaying a video which is based on a
video signal on a screen by a projection-type display device (a
so-called projector) , in the case of projecting video light from
an oblique direction with respect to the screen in the horizontal
direction or the vertical direction, the video displayed on the
screen is distorted into a trapezoid. Accordingly, the
projection-type display device mounts thereon a keystone correction
function to correct such a trapezoidal video into a rectangle.
[0006] In recent years, demand for improved image quality of the
display video has been increased, and in some cases, the
projection-type display device has mounted thereon a video signal
processing function to improve the image quality of the display
video by increasing the amount of information of the video signal,
and so on.
[0007] In the case where the video signal with the added black
stripe regions is inputted to the projection-type display device
that mounts thereon the keystone correction function and the video
signal processing function, it is necessary for the projection-type
display device to further mount thereon a black stripe region
detection function to detect the black stripe regions. When
processing the video signal by the video signal processing
function, the black stripe region detection function is
necessary.
[0008] When the projection-type display device is mounted with the
black stripe region detection function, the keystone correction
function, and a predetermined video signal processing function,
unless the respective functions are executed in an appropriate
order, then in some cases, some of the functions may not be
executed appropriately, or the cost of the device is increased
unnecessarily due to an increase of bandwidth or capacity of a
memory.
[0009] A first aspect of the embodiments provides a video signal
processing device including: a black stripe detector configured to
detect whether or not each pixel of an input video signal, in which
a part of an effective region is a black stripe region, is a pixel
included in the black stripe region, and to generate a black stripe
identification signal; a signal combiner configured to combine the
input video signal and the black stripe identification signal with
each other and to generate a combination signal; a keystone
correction processor configured to implement keystone correction
processing for the combination signal so as to correct a
trapezoidal distortion when the input video signal is projected
onto a screen, and to generate a keystone-corrected combination
signal; a signal separator configured to separate the
keystone-corrected combination signal into a keystone-corrected
video signal subjected to the keystone correction processing and a
keystone-corrected black stripe identification signal indicating
whether or not each pixel of the keystone-corrected video signal is
a pixel included in a black stripe region; and a video signal
processor configured to implement predetermined video signal
processing for the keystone-corrected video signal by using the
keystone-corrected video signal and the keystone-corrected black
stripe signal.
[0010] A second aspect of the embodiments provides a
projection-type display device including: the above-mentioned video
signal processing device; and a projector configured to project a
video signal which is outputted from the video signal processor
onto the screen.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a block diagram showing a video signal processing
device and a projection-type display device according to the first
embodiment.
[0012] FIG. 2 is a view showing an example of a video signal having
black stripe regions.
[0013] FIG. 3 is a diagram showing an example of a black stripe
identification signal.
[0014] FIG. 4 is a view showing an example of a video signal
subjected to keystone correction.
[0015] FIG. 5 is a block diagram showing a video signal processing
device and a projection-type display device according to the second
embodiment.
DETAILED DESCRIPTION
[0016] A description is made below of video signal processing
devices and projection-type display devices according to the
respective embodiments with reference to the accompanying
drawings.
First Embodiment
[0017] In FIG. 1, a video signal, in which a part of an effective
region is a black stripe region, is inputted to an input terminal
10. The video signal inputted to the input terminal 10 is referred
to as an input video signal. As an example, as shown in FIG. 2, the
input video signal is a video signal, in which such black stripe
regions SbR and SbL are added to the right and left sides of a
video region S0 with an aspect ratio 4:3, respectively, whereby a
video S1 with an aspect ratio 16:9 is formed.
[0018] The input video signal may be a video signal, in which the
black stripe regions are added to the right and left sides of a
video region with a first aspect ratio, whereby a video with a
second aspect ratio is formed, or may be a video signal in which
the black stripe regions are added to upper and lower sides of the
video with the first aspect ratio, whereby the video with the
second aspect ratio is formed. The input video signal is a video
signal in which the black stripe regions are a part of the
effective region.
[0019] The input video signal is inputted to a black stripe
detector 20 and a keystone correction signal controller 30. The
keystone correction signal controller 30 includes a signal combiner
31 and a signal separator 32. By an arbitrary technique such as a
black stripe region detection circuit described in Japanese Patent
No. 5010262, the black stripe detector 20 detects whether or not
the black stripe regions are present, and detects which portions of
a video are the black stripe regions.
[0020] As shown in FIG. 3, based on a detection result of the black
stripe regions, for example, the black stripe detector 20 generates
a black stripe identification signal that assigns "1" to pixels
included in a black stripe region SbR or SbL in FIG. 2, and assigns
"0" to pixels included in a video region S0 therein. In FIG. 3, the
respective pixels are enlarged for convenience of illustration.
[0021] That is, the black stripe identification signal is a signal
in which "1", indicating that each pixel belongs to the black
stripe region SbR or SbL, or "0", indicating that each pixel
belongs to the video region S0, is assigned in the same pixel unit
as that of the video signal.
[0022] The signal combiner 31 combines the video signal and the
black stripe identification signal with each other. For example, if
the video signal is an 8-bit one, then as an example, the signal
combiner 31 adds a 1-bit black stripe identification signal to a
least significant bit side of 8 bits, and generates a 9-bit
combination signal. At this time, the signal combiner 31
establishes a correspondence between a pixel position of the video
signal and a pixel position of the black stripe identification
signal, both of which are the same pixel position.
[0023] The way to combine the video signal and the black stripe
identification signal with each other by the signal combiner 31 is
not limited to the above-described example. When keystone
correction processing is implemented for the video signal, as will
be described later, the video signal and the black stripe
identification signal just need to be combined with each other so
that similar correction processing is also implemented for the
black stripe identification signal.
[0024] The combination signal is inputted to a keystone correction
processor 40. A correction instruction signal is inputted to the
keystone correction processor 40. The correction instruction signal
is generated in such a manner that a user operates an operation
unit (not shown), in order to correct a trapezoidal distortion of
the video signal projected onto a screen 80.
[0025] The video signal processing device may be configured to
automatically generate the correction instruction signal.
[0026] The keystone correction processor 40 writes the combination
signal, which is inputted thereto into a memory 50, and reads the
combination signal from the memory 50 so that the keystone
correction processing is implemented, and thereby generates a
keystone-corrected combination signal.
[0027] In the case where a trapezoidal distortion of a projection
video displayed on the screen 80 is a trapezoidal distortion in a
state where an upper side thereof in the vertical direction is wide
and a lower side thereof is narrow, the keystone-corrected
combination signal generated by the keystone correction processor
40 is a signal like a video S1k shown in FIG. 4.
[0028] As shown in FIG. 4, the video region S0 shown in FIG. 2 is
converted into a video region S0k in which an upper side in the
vertical direction is narrow and a lower side therein is wide. The
right and left black stripe regions SbR and SbL are converted into
black stripe regions SbRk and SbLk in which upper sides in the
vertical direction are wide and lower sides therein are narrow. In
order to allow an aspect ratio of the video region S0k to coincide
with the aspect ratio of the video region S0, black stripe regions
SbTk and SbBk are added to the upper and lower sides of the video
region S0k, respectively.
[0029] The keystone correction processor 40 generates the
keystone-corrected combination signal, which is shown in FIG. 4,
based on the combination signal in which the input video signal and
the black stripe identification signal are combined with each
other. Hence, the keystone-corrected combination signal becomes a
signal in which "1" is assigned to pixels included in the black
stripe region SbRk, SbLk, SbTk or SbBk, and "0" is assigned to
pixels included in the video S0k.
[0030] The keystone-corrected combination signal is inputted to the
signal separator 32. The signal separator 32 separates higher-order
8 bits and such a least-significant 1 bit from each other, and
thereby generates a keystone-corrected video signal and a
keystone-corrected black stripe identification signal from each
other. The keystone-corrected video signal and the
keystone-corrected black stripe identification signal are inputted
to a video signal processor 60.
[0031] The video signal processor 60 implements predetermined video
signal processing for the keystone-corrected video signal. For
example, the video signal processor 60 is a video signal processing
circuit that increases an amount of information of the video signal
and improves image quality of a display video. By using a memory
(not shown), the video signal processor 60 implements the video
signal processing for the keystone-corrected video signal.
[0032] Specifically, as an example, the video signal processor 60
is a frame rate conversion circuit, which generates an
interpolation frame, and inserts the generated interpolation frame
between frames adjacent to each other, and thereby converts a frame
rate of the keystone-corrected video signal. As another example,
the video signal processor 60 is an up-conversion circuit
(resolution conversion circuit), which increases the number of
lines in 1 frame, increases the number of pixels in 1 line, and
thereby increases the resolution.
[0033] For example, the frame rate conversion circuit converts a
video signal with a frame frequency of 60 Hz into a video signal
with a frame frequency of 120 Hz or 240 Hz. For example, the
up-conversion circuit converts an NTSC signal into a high vision
signal.
[0034] It is necessary for the video signal processor 60 to
generate the interpolation frame and generate an up-converted video
signal by using a pixel signal of the video region S0k in FIG.
4.
[0035] To the video signal processor 60, there are inputted: the
keystone-corrected video signal, and the keystone-corrected black
stripe identification signal, which properly identifies a portion
of the black stripe region SbRk,
[0036] SbLk, SbTk or SbBk and a portion of the video S0k in the
keystone-corrected video signal from each other. Hence, the video
signal processor 60 can implement the video signal processing for
improving the image quality by using the pixel signal of the video
region S0k.
[0037] In the interpolation frame generation in the frame rate
conversion circuit and the interpolation pixel generation in the
up-conversion circuit, if the pixels of the black stripe region are
referred to in the event of generating the pixels of the effective
region, then undesirably, such interpolation pixels are generated
that allow the black stripe to enter an interpolation effective
region. On the contrary, if the pixels of the effective region are
referred to in the event of generating the pixels of the black
stripe region, then undesirably, such interpolation pixels are
generated that allow the effective region to extend over an
interpolated black strip region.
[0038] The corrected black stripe information is inputted to the
video signal processor 60, and accordingly, the pixels of the
region determined to be the black stripe region can be avoided
being used for the interpolation of the effective region, and the
pixels the effective region can be avoided being used for the
interpolation of the region determined to be the black stripe
region.
[0039] Hence, the video signal processor 60 individually uses the
pixel signal of the video region S0k and the pixel signal on the
outside of the video region S0k in an appropriate manner, and can
thereby implement the video signal processing for improving the
image quality while preventing a deterioration of the image
quality.
[0040] A projector 70 projects video light, which is based on the
video signal outputted from the video signal processor 60, onto the
screen 80. For example, the projector 70 includes: a liquid crystal
panel for writing the video signal; a light source for irradiating
projection light onto the liquid crystal panel; and a projection
optical system for projecting the light, which transmits through or
is reflected on the liquid crystal panel, and onto the screen
80.
[0041] In accordance with the video signal processing device and
the projection-type display device according to the first
embodiment described above, the black stripe detector 20 detects
the black stripe regions based on the video signal that is not
subjected to the keystone correction processing yet, and
accordingly, the black stripe regions are detected
appropriately.
[0042] In accordance with the video signal processing device and
the projection-type display device according to the first
embodiment, the keystone correction processor 40 implements the
keystone correction processing for the video signal (combination
signal) before the video signal processor 60 implements the video
signal processing for the video signal, and accordingly, the cost
of the device is not increased unnecessarily.
[0043] Hence, in accordance with the video signal processing device
according to the first embodiment, it is possible to appropriately
execute the black stripe region detection function, the keystone
correction function, and the video signal processing function,
without unnecessarily increasing the cost of the device.
Second Embodiment
[0044] In a second embodiment shown in FIG. 5, the same reference
numerals are assigned to the same portions as those of the first
embodiment shown in FIG. 1, and a description thereof is
omitted.
[0045] In FIG. 5, the keystone correction signal controller 30
includes a video filter processor 33 and a black stripe filter
processor 34 in addition to the signal combiner 31 and the signal
separator 32.
[0046] The video filter processor 33 implements filtering
processing which uses peripheral pixels for each of the pixels of
the video signal inputted to the signal combiner 31. The black
stripe filter processor 34 implements filtering processing which
uses signals in the same range as that of the peripheral pixels in
the video filter processor 33 for a signal of each pixel unit of
the black stripe identification signal.
[0047] As understood from a comparison between FIG. 2 and FIG. 4,
the video region s0 is converted into the video region S0k with a
small area by the keystone correction processing. The filtering
processing, which uses the peripheral pixels, is implemented by the
video filter processor 33 and the black stripe filter processor 34,
whereby the processing is performed so that information to be
deleted partially remains.
[0048] The video filter processor 33 and the black stripe filter
processor 34 can be composed of low-pass filters or median
filters.
[0049] Preferably, the above-described peripheral pixels in the
video filter processor 33 and the black stripe filter processor 34
are varied in response to an extent of the reduction when the video
region S0 is converted into the video region S0k. Preferably, a
region of the peripheral pixels is increased as the extent of the
reduction is larger.
[0050] In FIG. 5, the video filter processor 33 and the black
stripe filter processor 34 are provided; however, the black stripe
filter processor 34 may be omitted, and only the video filter
processor 33 may be used.
[0051] The present invention is not limited to the first and second
embodiments described above, and is changeable in various ways
within the scope without departing from the scope of the present
invention. The respective constituents of FIG. 1 and FIG. 5 maybe
composed of hardware or software. The choice of hardware or
software is optional.
* * * * *