WO2019159850A1 - Signal processing device, signal processing system, signal processing method, and storage medium storing signal processing program - Google Patents

Abstract

[Problem] To provide a signal processing device which encodes an image while taking into account the efficiency of encoding processing, and a signal processing system, a signal processing method, and a signal processing program. [Solution] A storage unit 15 stores configuration pixel number information that indicates the number of pixels determined in advance in accordance with discrete cosine transformation processing. Depending on the number of pixels indicated by the configuration pixel number information stored in the storage unit 15, a pixel number adjustment unit 12 adjusts the number of pixels configuring an inputted image. An encoding unit 14 subjects the image, of which the number of pixels has been adjusted by the pixel number adjustment unit 12, to encoding processing including discrete cosine transformation processing. Also, the pixel number adjustment unit 12 performs processing involving adding additional pixels to the aforementioned inputted image depending on the number of pixels indicated by the configuration pixel number information.

Description

Signal processing apparatus, signal processing system, signal processing method, and storage medium storing signal processing program

The present invention relates to a signal processing device, a signal processing system, a signal processing method, and a signal processing program for transmitting and receiving video.

Various methods have been proposed for video coding. Non-Patent Document 1 is a video coding standard that divides and codes blocks called CTU (Coding Tree Unit), CU (Coding Unit), PU (Prediction Unit), and TU (Transform Unit). It describes about HEVC (High Efficiency Video Coding).

And Non-Patent Document 2 describes the operation guidelines of the HEVC standard in digital broadcasting.

FIG. 13 is an explanatory diagram showing an example in which a glance of video (hereinafter referred to as a picture) is divided into CTU, CU, PU, and TU.

FIG. 13 shows an example of a picture in which the number of pixels in the horizontal direction is 832 and the number of pixels in the vertical direction is 480. FIG. 13 shows that the picture is divided into CTUs each having 64 horizontal pixels and 64 vertical pixels. Further, FIG. 13 shows that the CTU is divided into CUs. FIG. 13 shows that a CU is divided into PUs for prediction processing according to image characteristics. FIG. 13 shows that a CU is divided into TUs for conversion processing according to image characteristics.

Therefore, it can be seen that for all CUs, the CU size is larger than the TU size (feature A).

FIG. 14 is an explanatory diagram showing the maximum pixel size and the minimum pixel size of CTU, CU, PU, and TU that can be used in the HEVC standard. The number of pixels in the horizontal direction and the number of pixels in the vertical direction are shown in the form of the number of pixels in the horizontal direction × the number of pixels in the vertical direction.

As shown in FIG. 14, in the HEVC standard, the maximum pixel size of CTU is 64 × 64. Further, as shown in FIG. 14, in the HEVC standard, the minimum pixel size of CTU is 16 × 16. In addition, in the HEVC standard, the pixel size of CTU is 32 × 32.

As shown in FIG. 14, in the HEVC standard, the maximum pixel size of a CU is 64 × 64. Further, as shown in FIG. 14, in the HEVC standard, the minimum pixel size of the CU is 8 × 8.

As shown in FIG. 14, in the HEVC standard, the maximum pixel size of PU is 64 × 64. Further, as shown in FIG. 14, in the HEVC standard, the minimum pixel size of PU is 8 × 4 and 4 × 8.

As shown in FIG. 14, in the HEVC standard, the maximum pixel size of TU is 32 × 32. Further, as shown in FIG. 14, in the HEVC standard, the minimum pixel size of TU is 4 × 4.

In the HEVC standard, the CTU pixel size is 32 × 32. Therefore, in the HEVC standard, the CTU pixel sizes include 64 × 64, 32 × 32, and 16 × 16, but may not correspond to the pixel size of the picture.

Specifically, in the example shown in FIG. 13, 480 which is the number of pixels in the vertical direction of the picture is not a multiple of 64 which is the maximum pixel size (vertical direction) of the CTU. Therefore, when the picture is divided into CTUs having the maximum pixel size in order from the upper side of the picture, the pixel size of the block included in the CTU at the lower end of the picture is 64 × 32. Then, the pixel size of the CU included in the CTU must be 32 × 32 or less. In addition, the CTU is divided into a plurality of CUs.

Therefore, when the pixel size of the picture to be encoded (also referred to as the encoded picture size) is not a multiple of the maximum pixel size of the CTU, the picture may be divided into CTUs or CUs having a smaller pixel size at the edge of the picture. I understand (feature B).

Next, restrictions on the pixel size of the picture to be encoded, the CTU pixel size, and the TU pixel size in the operation guidelines described in Non-Patent Document 2 will be described. Here, in the case of video digital content whose format is 1080 / P (hereinafter referred to as 1080 / P digital content), and video digital content whose format is 2160 / P (hereinafter referred to as 2160 / P digital content). )). 1080 / P indicates a digital broadcast format in which a video having 1920 pixels in the horizontal direction and 1080 pixels in the vertical direction is progressively displayed. 2160 / P indicates a digital broadcast format in which a video having 3840 pixels in the horizontal direction and 2160 pixels in the vertical direction is progressively displayed.

In “Appendix 5 Guidelines for Operation of HEVC Standard in Television Service” in “Table 4-8 Parameters for Image Size” in 1920, as a picture to be encoded for 1080 / P digital content, 1920 × It is shown that a size of 1080 and a size of 1020 × 1088 can be accommodated.

Also, in “Table 4-5 Sequence Parameter Set (Sequence Parameter Set, SPS)” in “Appendix 5 Guidelines for Operation of HEVC Standard in Television Service” in Non-Patent Document 2, the pixel size of 32 × 32 for CTU It is shown that the pixel size of 4 × 4 to 32 × 32 can be handled for TU.

Patent Document 1 describes a prediction block corresponding to each second block based on a first block to which the intra prediction encoding mode is applied and a plurality of second blocks that are units of orthogonal transform. The encoding of errors is described.

JP 2017-73602 A JP 2013-121044 A Japanese Patent Laying-Open No. 2015-076666 International Publication No. 2015/151513

However, according to Non-Patent Documents 1 and 2, there is a problem that the compression efficiency of low-bit-rate video encoding based on the HEVC standard is restricted by the above-described feature A and feature B. This is because the HEVC standard defines a coded picture size corresponding to each digital content without considering the minimum overhead code amount in block division based on the quadtree structure.

Here, the number of discrete cosine transform (DCT (Discrete Cosine Transform)) coefficients included in each picture affects the minimum overhead code amount. The DCT coefficient is required for the video decoding apparatus to decode the encoded video. When the DCT coefficient is a significant value, a positive / negative code having a low correlation needs to be transmitted.

According to the operation guidelines described in Non-Patent Document 2, for example, the encoded picture size of 2160 / P digital content is limited to 3840 × 2160. Therefore, even if the CTU is set to 64 × 64 which is the maximum pixel size, 24840 DCT coefficients must be transmitted. Note that the 24840 DCT coefficients are obtained by dividing each CTU so that the number of CUs is minimized and dividing the CU so that the number of TUs is minimized. This is the number of DCT coefficients of the (Direct Current) component.

When 24840 DCT coefficients are all significant values, the code amount corresponding to the positive and negative codes (that is, the minimum overhead code amount) is 24840 [bit] × 59.94 [Hz] = about 1.5. It will also be [Mbps].

In other words, considering that there is other information to be transmitted, according to Non-Patent Documents 1 and 2, for example, it is difficult to set the minimum bit rate of 2160 / P digital content to 1.5 Mbps or less. It is shown that. This indicates that the compression efficiency of low bit rate video encoding based on the HEVC standard is limited.

Therefore, an object of the present invention is to provide a signal processing device, a signal processing system, a signal processing method, and a signal processing program for encoding video in consideration of the efficiency of encoding processing.

In the signal processing device according to the present invention, a storage unit that stores preset pixel number information indicating a predetermined number of pixels according to discrete cosine transform processing, and a set pixel number information stored in the storage unit indicate A pixel number adjusting unit that adjusts the number of pixels constituting the input video according to the number of pixels, and an encoding process including a discrete cosine transform process on the video in which the pixel number adjusting unit has adjusted the number of pixels And an encoding means.

The signal processing system according to the present invention includes any one of the signal processing apparatuses and a decoding processing apparatus that performs a decoding process according to the encoding process.

The signal processing method according to the present invention is based on the number of pixels indicated by the set pixel number information stored in the storage means in which the set pixel number information indicating the predetermined number of pixels corresponding to the discrete cosine transform processing is stored. A pixel number adjusting step for adjusting the number of pixels constituting the inputted video, and a coding step for performing a coding process including a discrete cosine transform process on the video whose number of pixels is adjusted in the pixel number adjusting step; It is characterized by including.

The signal processing program according to the present invention is indicated by set pixel number information stored in a storage unit in which set pixel number information indicating a predetermined number of pixels corresponding to discrete cosine transform processing is stored in a computer. A pixel number adjustment process for adjusting the number of pixels constituting the input video according to the number of pixels, and an encoding process including a discrete cosine transform process for the video in which the number of pixels is adjusted by the pixel number adjustment process An encoding process is executed.

According to the present invention, the minimum overhead code amount in the encoding process can be reduced.

It is a block diagram which shows the structural example of the video transmission system of 1st Embodiment. It is explanatory drawing which shows the example of the pixel number database memorize | stored in the memory | storage part. It is explanatory drawing which shows the example of a pixel aspect database. It is a flowchart which shows the operation example of the encoding apparatus in 1st Embodiment. It is a flowchart which shows operation | movement of the decoding apparatus in 1st Embodiment. It is a block diagram which shows the structural example of the video transmission system of 2nd Embodiment. It is a flowchart which shows the operation example of the encoding apparatus in 2nd Embodiment. It is a flowchart which shows the operation example of the decoding apparatus in 2nd Embodiment. It is a block diagram which shows the structural example of the video transmission system of 3rd Embodiment. It is a flowchart which shows the operation example of the encoding apparatus in 3rd Embodiment. It is a flowchart which shows the operation example of the decoding apparatus in 3rd Embodiment. It is a block diagram which shows the structural example of the signal processing apparatus of 4th Embodiment. It is explanatory drawing which shows the example in which a glance of an image | video is divided | segmented into CTU, CU, PU, and TU. It is explanatory drawing which shows the maximum pixel size and minimum pixel size of CTU, CU, PU, and TU which can be utilized by HEVC standard.

Embodiment 1. FIG.
A video transmission system according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram illustrating a configuration example of a video transmission system (signal processing system) 100 according to the first embodiment of this invention. As shown in FIG. 1, the video transmission system 100 according to the first embodiment of the present invention includes an encoding device 110 and a decoding device 120.

The encoding device 110 adjusts the number of pixels of the input video and the aspect ratio of each pixel. Then, the encoding device 110 encodes the adjusted video.

The video encoded by the encoding device 110 is transmitted by the transmission device 210. Also, the encoded video transmitted by the transmission device 210 is received by the reception device 220. Then, the receiving device 220 inputs the received encoded video to the decoding device 120.

The decoding device 120 decodes the input encoded video. Then, the decoding device 120 restores the number of pixels and the aspect ratio of the decoded video to the state before adjustment.

As illustrated in FIG. 1, the encoding device 110 includes a setting unit 111, a size adjustment unit 112, a pixel aspect adjustment unit 113, an encoding processing unit 114, and a storage unit 115.

The setting unit 111, the size adjusting unit 112, the pixel aspect adjusting unit 113, and the encoding processing unit 114 are realized by, for example, a CPU (Central Processing Unit) that executes processing according to program control and a plurality of circuits. The storage unit 115 is realized by a storage unit such as a memory.

The setting unit 111 sets the number of pixels of the image after the adjustment by the size adjustment unit 112 and the aspect ratio of the pixel after the adjustment by the pixel aspect adjustment unit 113 based on the number of pixels of the image input to the encoding device 110. To do.

The size adjusting unit 112 adjusts the video input to the encoding device 110 to a video having a predetermined number of pixels based on the setting result by the setting unit 111.

The pixel aspect adjustment unit 113 adjusts the pixel aspect ratio in the video whose number of pixels is adjusted by the size adjustment unit 112 based on the setting result by the setting unit 111.

The encoding processing unit 114 encodes an image of the number of pixels adjusted by the size adjusting unit 112 and a pixel whose aspect ratio is adjusted by the pixel aspect adjusting unit 113. Then, the encoding processing unit 114 inputs the encoded video to the transmission device 210.

Information is stored in the storage unit 115 in advance. Specifically, in the storage unit 115, for example, pixels in which set pixel number information, which is information indicating the number of pixels of an adjusted video set by the setting unit 111 according to the format of the input video, is registered A number database is stored.

FIG. 2 is an explanatory diagram illustrating an example of a pixel number database stored in the storage unit 115. The pixel number database corresponds to each encoded video format, and has a value corresponding to the number of pixels in the horizontal direction and the number of pixels in the vertical direction according to the discrete cosine transform process in the encoding process, and the number of pixels in the dummy data. Is set.

In the example illustrated in FIG. 2, in a pixel number database, an image whose encoded video format is represented as “1080 / I” has a horizontal pixel number (indicated as “pic_width_in_luma_samples” in FIG. 2) “1920. ", The number of pixels in the vertical direction (shown as" pic_height_in_luma_samples "in FIG. 2) is" 1088 ", and the value corresponding to the number of pixels of dummy data (shown as" conf_win_bottom_offset "in FIG. 2) is" 4 ". It is shown that a certain picture is included. Further, in the example shown in FIG. 2, in the pixel number database, the video represented as the encoded video format “1080 / I” has the horizontal pixel count “1920” and the vertical pixel count. The number is “544”, and it is indicated that a video whose value corresponding to the number of pixels of the dummy data is “2” is included.

In the example shown in FIG. 2, in a pixel number database, a video represented as having an encoded video format of “1080 / P” has a horizontal pixel count of “1920” and a vertical pixel count of It is indicated that “1080” is included, and an image whose value corresponding to the number of pixels of the dummy data is “0” is included. Further, in the example shown in FIG. 2, in the pixel number database, a video represented as having an encoded video format of “1080 / P” has a horizontal pixel count of “1920” and a vertical pixel count. The number is “1088”, and it is indicated that the video whose value corresponding to the number of pixels of the dummy data is “4” is included. In the example shown in FIG. 2, in a pixel number database, a video represented as having an encoded video format of “1080 / P” has a horizontal pixel count of “1440” and a vertical pixel count of It is indicated that “1080” is included, and an image whose value corresponding to the number of pixels of the dummy data is “0” is included.

In the example shown in FIG. 2, in a video represented as an encoded video format “2160 / P” in the pixel number database, the number of pixels in the horizontal direction is “3840” and the number of pixels in the vertical direction is It is “2160”, and it is indicated that a video whose value corresponding to the number of pixels of the dummy data is “0” is included. Further, in the example shown in FIG. 2, in the image represented by the pixel number database as the encoded video format being “2160 / P”, the number of pixels in the horizontal direction is “2880”, and the pixels in the vertical direction The number is “2160”, and it is indicated that the video whose value corresponding to the number of pixels of the dummy data is “0” is included. In the example shown in FIG. 2, in a video represented as an encoded video format “2160 / P” in the pixel number database, the number of pixels in the horizontal direction is “3840” and the number of pixels in the vertical direction is It is “2176”, and it is shown that a video whose value corresponding to the number of pixels of the dummy data is “8” is included. Further, in the example shown in FIG. 2, in the image represented by the pixel number database as the encoded video format being “2160 / P”, the number of pixels in the horizontal direction is “2880”, and the pixels in the vertical direction It is shown that the number is “2176” and the video whose value corresponding to the number of pixels of the dummy data is “8” is included.

In the example shown in FIG. 2, in the image represented by the pixel number database as the encoded video format being “4320 / P”, the number of pixels in the horizontal direction is “7680” and the number of pixels in the vertical direction is It is indicated that “4320” is included, and a video whose value corresponding to the number of pixels of the dummy data is “0” is included.

Also, the storage unit 115 stores, for example, a pixel aspect database in which the adjusted pixel aspect ratio set by the setting unit 111 according to the format of the input video is registered.

FIG. 3 is an explanatory diagram showing an example of a pixel aspect database. In the example shown in FIG. 3, “1” that is an identifier corresponding to 1: 1 and “14” that is an identifier corresponding to 4: 3 are registered in the column “aspect_ratio_idc” indicating the aspect ratio of the pixel. Yes. The pixel aspect ratio of 1: 1 means that the pixel has a square pixel having the same horizontal length and vertical length. The pixel aspect ratio of 4: 3 means that the pixel is a rectangular pixel in which the horizontal length and the vertical length of the pixels are different from each other and the ratio is 4: 3.

1, the decoding device 120 includes a decoding processing unit 121, a restoration setting unit 122, a size restoration unit 123, a pixel aspect restoration unit 124, and a storage unit 125.

The decoding processing unit 121, the restoration setting unit 122, the size restoration unit 123, and the pixel aspect restoration unit 124 are realized by, for example, a CPU that executes processing according to program control and a plurality of circuits.

The decoding processing unit 121 decodes the encoded video input by the receiving device 220.

The restoration setting unit 122 sets the size of the restored video based on the number of pixels of the video decoded by the decoding processing unit 121.

The size restoration unit 123 adjusts the size of the video decoded by the decoding processing unit 121 based on the setting result by the restoration setting unit 122.

The pixel aspect restoration unit 124 adjusts the aspect ratio of the pixels of the video whose size has been adjusted by the size restoration unit 123 based on the number of pixels of the video decoded by the decoding processing unit 121.

Information is stored in the storage unit 125 in advance. Specifically, the storage unit 125 stores, for example, a restoration database in which the restored video size set by the restoration setting unit 122 according to the number of decoded video pixels is registered.

In the restoration database, for example, information corresponding to information registered in the pixel aspect database is registered.

Next, the operation of the video transmission system 100 according to the first embodiment of the present invention will be described. FIG. 4 is a flowchart showing an operation example of the encoding apparatus 110 according to the first embodiment of the present invention.

As illustrated in FIG. 4, when video is input to the encoding device 110, the setting unit 111 is a database in which information corresponding to the format of the video input to the encoding device 110 is stored in the storage unit 115. And the number of pixels of the image after adjustment by the size adjustment unit 112 is set (step S101). In this example, it is assumed that a video having a format of 2160 / P (for example, a video having a horizontal pixel number “3840” and a vertical pixel number “2160”) is input to the encoding device 110. .

For example, the setting unit 111 corresponds to the encoded video format “2160 / P” in the pixel number database of the storage unit 115 in response to the video having the format 2160 / P being input to the encoding device 110. The number of attached horizontal pixels and the number of vertical pixels are read out. In the example illustrated in FIG. 2, the encoded video format “2160 / P” includes a horizontal pixel count “2880”, a vertical pixel count “2160”, a horizontal pixel count “3840”, and a vertical pixel count. The number “2176” is associated with a value “8” corresponding to the number of pixels of dummy data to be added.

Therefore, the setting unit 111, for example, in accordance with an operation performed by the administrator, the horizontal pixel number “2880” and the vertical pixel number associated with the encoded video format “2160 / P” in the pixel number database of the storage unit 115. Assume that the number of pixels in the direction “2160” is read out. For example, it is assumed that the setting unit 111 reads the identifier “14” from the pixel aspect database of the storage unit 115 in accordance with an operation performed by the administrator.

Then, the setting unit 111 sets the number of pixels of the adjusted image to the number of pixels in the horizontal direction “2880” and the number of pixels in the vertical direction “2160”. The setting unit 111 sets the adjusted pixel aspect ratio to “4: 3”.

The size adjusting unit 112 adjusts the video input to the encoding device 110 to a video having a predetermined number of pixels based on the setting result by the setting unit 111 (step S102).

In this example, the setting unit 111 sets the number of pixels of the adjusted video to the number of pixels in the horizontal direction “2880” and the number of pixels in the vertical direction “2160”. Therefore, the size adjustment unit 112 adjusts the video input to the encoding device 110 to the number of pixels in the horizontal direction “2880” and the number of pixels in the vertical direction “2160”. In this example, the format of the video input to the encoding device 110 is 2160 / P, the number of pixels in the horizontal direction of the video is “3840”, and the number of pixels in the vertical direction is “2160”. . Therefore, the size adjustment unit 112 reduces the number of pixels in the horizontal direction from “3840” to “2880” in the video input to the encoding device 110. Specifically, for example, in the video input to the encoding device 110, the size adjustment unit 112 thins out 1040 pixels from 3840 pixels arranged in the horizontal direction, and sets the number of pixels in the horizontal direction to “2880”. To "". As a method for reducing the number of pixels, for example, a known method is used. Then, the number of pixels in the horizontal direction is reduced to 3/4.

The pixel aspect adjustment unit 113 adjusts the pixel aspect ratio in the video whose number of pixels has been adjusted by the size adjustment unit 112 based on the setting result in the setting unit 111 (step S103).

In this example, the setting unit 111 sets the aspect ratio of the adjusted pixel to “4: 3”. Therefore, the pixel aspect adjustment unit 113 adjusts the pixel aspect ratio in the video whose number of pixels is adjusted by the size adjustment unit 112 to “4: 3”. Therefore, the pixels in the video whose number of pixels has been adjusted by the size adjusting unit 112 are enlarged by 4/3 times in the horizontal direction.

The encoding processing unit 114 encodes an image having the number of pixels set by the size adjusting unit 112 and a pixel having an aspect ratio adjusted by the pixel aspect adjusting unit 113 (step S104).

In this example, the video to be encoded by the encoding processing unit 114 has “2880” as the number of pixels in the horizontal direction and “2160” as the number of pixels in the vertical direction. In the HEVC standard, CTU pixel sizes include 64 × 64, 32 × 32, and 16 × 16. Then, since 2880 ÷ 64 = 45, the video is first divided into 33 rows of CTUs arranged in a horizontal direction with 45 pixels each having a pixel size of 64 × 64. Therefore, out of 2160 vertical pixels, 2160− (64 × 33) = 2112 are included in a CTU having a pixel size of 64 × 64. The remaining image is a CTU having a pixel size of 32 × 32 including pixels for 32 rows and a pixel size of 16 × 16 including pixels for the remaining 16 rows among 48 rows of pixels arranged in the horizontal direction. Divided into CTUs. Since 2880 ÷ 32 = 90, the remaining image is a CTU of one row arranged in the horizontal direction with a pixel size of 32 × 32 and 2880 ÷ 16 = 180, so that 16 × 16 Are divided into one row of CTUs arranged in a horizontal direction with a pixel size of 180 pixels.

The maximum pixel size of a TU is 32 × 32, and a CTU having a pixel size of 64 × 64 includes four TUs. Therefore, in the video, the DCT coefficient is 45 × 33 × 4 × 3 = 17820 when a portion of 33 rows of CTUs arranged in a horizontal direction with a pixel size of 64 × 64 is encoded.

Also, a CTU having a pixel size of 32 × 32 and a CTU having a pixel size of 16 × 16 each include one TU. Therefore, in the remaining video, 90 rows of CTUs arranged in a horizontal direction with a pixel size of 32 × 32 and one row of 180 rows arranged in a horizontal direction with a pixel size of 16 × 16 The DCT coefficient when the CTU portion is encoded is (90 + 180) × 3 = 810.

Then, the number of DCT coefficients when the entire video is encoded is 17820 + 810 = 18630.

When the size of the 2160 / P format image is not adjusted as in this example, the number of pixels in the horizontal direction is “3840” and the number of pixels in the vertical direction is “2160”. Then, the video is first divided into 33 rows of CTUs each having 60 pixels arranged in the horizontal direction with a pixel size of 64 × 64. The rest of the video consists of one row of CTUs arranged in a horizontal direction with a pixel size of 32 × 32 and one row of CTUs arranged in a horizontal direction with a pixel size of 16 × 16 and 240 pixels. Divided into parts.

Therefore, the DCT coefficient in the case where the CTU portion for 33 rows arranged in the horizontal direction with the pixel size of 64 × 64 in the video is encoded is 60 × 33 × 4 × 3 = 23760. Also, in the video, 120 rows of CTUs arranged in a horizontal direction with a pixel size of 32 × 32 and one row of CTUs arranged in a horizontal direction with a pixel size of 16 × 16 and 240 pixels. The DCT coefficient when the portion is encoded is (120 + 240) × 3 = 1080.

Then, when adjustment of the size of the video in the 2160 / P format similar to this example is not performed, the number of DCT coefficients when the entire video is encoded is 23760 + 1080 = 24840.

Therefore, according to this example, it can be seen that the size of the video is adjusted and the number of DCT coefficients is reduced from 24840 to 18630.

The encoding processing unit 114 inputs the video encoded in the process of step S104 to the transmission device 210. Then, the video input to the transmission device 210 is transmitted by the transmission device 210.

FIG. 5 is a flowchart showing the operation of the decoding device 120 according to the first embodiment of the present invention. The video encoded by the encoding device 110 and received by the reception device 220 is input to the decoding device 120.

First, the decoding processing unit 121 decodes the input encoded video (step S201).

Then, the restoration setting unit 122 identifies the number of pixels of the video based on the video decoded by the decoding processing unit 121 (step S202). Then, based on the number of pixels specified by the restoration setting unit 122 in step S202, the size restoration unit 123 adjusts the size of the video decoded by the decoding processing unit 121 (step S203).

Further, the pixel aspect restoration unit 124 adjusts the aspect ratio of the pixels of the video whose size has been adjusted by the size restoration unit 123 based on the number of pixels of the video decoded by the decoding processing unit 121 (step S204).

That is, the video encoded by adjusting the number of pixels and the aspect ratio is decoded by the process of step S201, adjusted by the processes of steps S203 and S204, and restored.

According to this embodiment, the encoding processing unit 114 performs the encoding process after the size adjusting unit 112 and the pixel aspect adjusting unit 113 adjust the number of pixels and the aspect ratio in consideration of the number of DCT coefficients. Therefore, the number of DCT coefficients used for encoding can be reduced as compared with the case where such adjustment is not performed. Therefore, the minimum overhead code amount in the encoding process can be reduced. In this example, the size adjustment unit 112 thins out some of the pixels arranged in the horizontal direction based on the setting result in the setting unit 111, and the pixel aspect adjustment unit 113 adjusts the aspect ratio of the pixel. However, the size adjustment unit 112 may be configured to thin out some of the pixels arranged in the vertical direction, and the pixel aspect adjustment unit 113 may be configured to adjust the pixel aspect ratio.

In this embodiment, the case where a video having a format of 2160 / P is input to the encoding device 110 has been described as an example. However, the horizontal pixel count “1920” having a format of 1080 / P and Even when a video having the number of pixels “1080” in the vertical direction is input, the same process can achieve the effect of reducing the number of DCT coefficients used for encoding.

Specifically, the size adjusting unit 112 decreases the number of pixels in the horizontal direction from “1920” to “1440”. Then, the number of pixels in the horizontal direction is reduced to 3/4. Then, the pixel aspect adjustment unit 113 adjusts the aspect ratio of the pixels in the video whose number of pixels is adjusted by the size adjustment unit 112 to “4: 3”.

Then, the image has 16 rows of CTUs arranged in a horizontal direction with a pixel size of 64 × 64 and 22 rows of CTUs, and 32 rows of CTUs arranged in a horizontal direction with a pixel size of 32 × 32 respectively. 45 rows arranged in a horizontal direction with a pixel size of 32 × 32, CTUs of one row arranged in a horizontal direction with a pixel size of 16 × 16, and 8 × 8 It is divided into one row of CUs arranged in a horizontal direction with a pixel size.

Then, in the video, the DCT coefficient in the case of encoding the CTU portion of 16 rows arranged in the horizontal direction with the pixel size of 64 × 64 is 22 × 16 × 4 × 3 = 4224. Also, in the video, the DCT coefficients when coding the 32 rows of CTUs of 32 rows arranged in the horizontal direction with a pixel size of 32 × 32 are 1 × 32 × 3 = 96. Then, in the video, the DCT coefficient in the case where the CTU portion for one row arranged in the horizontal direction with the pixel size of 32 × 32 is encoded is 45 × 1 × 3 = 135.

In a video, when coding 90 rows of CTUs for one row arranged in a horizontal direction with a pixel size of 16 × 16, the DCT coefficients are 90 × 1 × 3 = 270. In addition, in the video, the DCT coefficient when encoding the CU portion of one row arranged in the horizontal direction with the pixel size of 8 × 8 is 180 × 1 × 3 = 540.

Then, the number of DCT coefficients when the size-adjusted image is encoded after the size is adjusted so that the number of pixels in the horizontal direction becomes “1440” and the number of pixels in the vertical direction becomes “1080”. Is 4224 + 96 + 135 + 270 + 540 = 5265.

On the other hand, an image that is not processed by the size adjustment unit 112 and has 1080 pixels in the vertical direction and 1920 pixels in the horizontal direction has a pixel size of 64 × 64 and 30 in the horizontal direction. 16 rows of CTUs arranged in a row, 60 rows of CTUs arranged in a horizontal direction with a pixel size of 32 × 32, and 120 pieces of CTUs arranged in a horizontal direction with a pixel size of 16 × 16 It is divided into a CTU portion for one row and a CU portion for one row arranged in the horizontal direction with 8 × 8 pixel size.

Then, when a video having 1080 vertical pixels and 1920 horizontal pixels is encoded, 30 rows of 16 pixels arranged in a horizontal direction with a 64 × 64 pixel size are provided. The number of DCT coefficients when the CTU part is encoded is 30 × 16 × 4 × 3 = 5760. Also, one row of CTUs arranged in a horizontal direction with a pixel size of 32 × 32 and one row of CTUs arranged in a horizontal direction with a pixel size of 16 × 16 and 120 rows each. The number of DCT coefficients in the case where the CU portion for one row arranged in the horizontal direction with the pixel size of 8 × 8 is encoded is (60 + 120 + 240) × 3 = 1260.

Therefore, the number of DCT coefficients when a video having 1080 pixels in the vertical direction and 1920 pixels in the horizontal direction is encoded is 5760 + 1260 = 7020.

Therefore, even when a video having a format of 1080 / P and having a horizontal pixel count of “1920” and a vertical pixel count of “1080” is input, the processing according to the present embodiment enables encoding. The effect is that the number of DCT coefficients used can be reduced from 7020 to 5265.

Embodiment 2. FIG.
Next, a video transmission system according to a second embodiment of the present invention will be described with reference to the drawings. FIG. 6 is a block diagram illustrating a configuration example of a video transmission system (signal processing system) 300 according to the second embodiment of this invention. As illustrated in FIG. 6, the video transmission system 300 according to the second exemplary embodiment of the present invention includes an encoding device 310 and a decoding device 320.

The encoding device 310 adjusts the number of pixels by adding dummy pixels to the input video. Then, the encoding device 310 encodes the adjusted video.

The video encoded by the encoding device 310 and cutout range information described later are transmitted by the transmission device 210. Also, the encoded video and cutout range information described later transmitted by the transmission device 210 are received by the reception device 220. Then, the receiving device 220 inputs the received encoded video and clipping range information described later to the decoding device 320.

The decoding device 320 decodes the input encoded video. Then, based on the cut-out range information, the decoding device 320 erases the added dummy pixels from the decoded video and restores the state before adjustment.

6, the encoding device 310 includes a setting unit 311, a size adjustment unit 312, a cutout range setting unit 313, an encoding processing unit 314, and a storage unit 315.

The setting unit 311, the size adjustment unit 312, the cutout range setting unit 313, and the encoding processing unit 314 are realized by, for example, a CPU that executes processing according to program control and a plurality of circuits.

The setting unit 311 sets the number of pixels of the video after the adjustment by the size adjustment unit 312 based on the number of pixels of the video input to the encoding device 310.

The size adjustment unit 312 adds a dummy pixel to the video input to the encoding device 310 based on the setting result by the setting unit 311 to adjust the video to a predetermined number of pixels.

The cut-out range setting unit 313 generates cut-out range information, which is information indicating the range excluding the dummy pixels added by the size adjustment unit 312 from the image after adjustment by the size adjustment unit 312.

The encoding processing unit 314 encodes an image having the number of pixels to which dummy pixels are added by the size adjusting unit 312. Then, the encoding processing unit 314 inputs the encoded video and the cut range information generated by the cut range setting unit 313 to the transmission device 210.

Information is stored in the storage unit 315 in advance. Specifically, the storage unit 315 stores, for example, a pixel number database in which the number of pixels of the adjusted video set by the setting unit 311 according to the format of the input video is registered. Specifically, for example, the pixel number database illustrated in FIG. 2 is stored in the storage unit 315.

As illustrated in FIG. 6, the decoding device 320 includes a decoding processing unit 321 and a size restoring unit 323.

The decryption processing unit 321 and the size restoration unit 323 are realized by, for example, a CPU that executes processing according to program control and a plurality of circuits.

The decoding processing unit 321 decodes the encoded video input by the receiving device 220.

The size restoration unit 323 cuts the video in the range indicated by the cut range information from the video decoded by the decoding processing unit 321 based on the cut range information.

Next, the operation of the video transmission system 300 according to the second embodiment of the present invention will be described. FIG. 7 is a flowchart showing an operation example of the encoding apparatus 310 according to the second embodiment of the present invention.

As shown in FIG. 7, when video is input to the encoding device 310, the setting unit 311 stores information corresponding to the format of the video input to the encoding device 310 in the storage unit 315. And the number of pixels of the image after adjustment by the size adjustment unit 312 is set (step S301). In this example, it is assumed that a video having a format of 2160 / P (for example, a video having a horizontal pixel number “3840” and a vertical pixel number “2160”) is input to the encoding device 110. .

For example, the setting unit 311 corresponds to the encoded video format “2160 / P” in the pixel number database of the storage unit 315 in response to the video having the format 2160 / P being input to the encoding device 110. The number of attached horizontal pixels and the number of vertical pixels are read out. In the example shown in FIG. 2, the encoded video format “2160 / P” includes an image having a horizontal pixel number “3840” and a vertical pixel number “2160”, a horizontal pixel number “3840”, A vertical number of pixels “2176” and an image having a value “8” corresponding to the number of pixels of dummy data to be added are included.

Therefore, the setting unit 311, for example, in accordance with the operation performed by the administrator, the horizontal pixel number “3840” associated with the encoded video format “2160 / P” in the pixel number database of the storage unit 115 and the vertical It is assumed that the number of pixels “2176” in the direction and the value “8” corresponding to the number of pixels of dummy data are read. The value “8” corresponds to the number of pixels “16” of the dummy data.

Then, the setting unit 311 sets the number of pixels of the adjusted video to the number of pixels in the horizontal direction “3840” and the number of pixels in the vertical direction “2176”. Further, the setting unit 311 sets the number of pixels of the dummy data to “16”.

The size adjusting unit 312 adjusts the video input to the encoding device 310 to a video having a predetermined number of pixels based on the setting result by the setting unit 311 (step S302). Specifically, the size adjustment unit 312 receives, as an input to the encoding device 310, a video based on dummy data in which 16 pixels arranged in the vertical direction in the video are arranged across both ends in the horizontal direction of the video. To the video. Note that an image based on dummy data is also referred to as an image based on dummy pixels, and that an image based on dummy data is added is also referred to as a dummy pixel being added.

In this example, 16 pixels of dummy data arranged in the vertical direction are added to the vertical direction of the video in addition to 2160 pixels in the vertical direction across both ends of the video in the horizontal direction. Therefore, in the video after the adjustment processing by the size adjustment unit 312, that is, the video to be encoded by the encoding processing unit 314 in the process of step S 304 described later, the number of pixels in the vertical direction is 2176, and the horizontal pixels The number is 3840.

The cutout range setting unit 313 cuts out a range other than the video based on the dummy data, that is, the range of the video input to the encoding device 310 among the videos that have been adjusted by the size adjustment unit 312 in the process of step S302. Range information is generated (step S303).

The encoding processing unit 314 encodes the video having the number of pixels to which the dummy pixels are added by the size adjusting unit 312 (step S304). Then, the encoding processing unit 314 inputs the encoded video and the cut range information generated by the cut range setting unit 313 to the transmission device 210.

The encoded video and cutout range information input to the transmission device 210 are transmitted by the transmission device 210. Also, the encoded video and cutout range information transmitted by the transmission device 210 are received by the reception device 220. Then, the receiving device 220 inputs the received encoded video and cutout range information to the decoding device 320.

In this example, the video to be encoded by the encoding processing unit 314 has “3840” as the number of pixels in the horizontal direction and “2176” as the number of pixels in the vertical direction. In the HEVC standard, CTU pixel sizes include 64 × 64, 32 × 32, and 16 × 16. Then, 3840 ÷ 64 = 60. Also, 2172 ÷ 64 = 34. Therefore, the video is divided into 34 rows of CTUs each having 60 pixels arranged in the horizontal direction with a pixel size of 64 × 64. Therefore, in the video, the DCT coefficient in the case where the CTU portion for 34 rows arranged in the horizontal direction with the pixel size of 64 × 64 is encoded is 60 × 34 × 4 × 3 = 24480.

Therefore, the number of DCT coefficients when the entire video is encoded is 24480.

When adjustment is not performed with the video size of the 2160 / P format similar to this example, the number of pixels in the horizontal direction is “3840” and the number of pixels in the vertical direction is “2160”. Then, the video is first divided into 33 rows of CTUs each having 60 pixels arranged in the horizontal direction with a pixel size of 64 × 64. The rest of the video consists of one row of CTUs arranged in a horizontal direction with a pixel size of 32 × 32 and one row of CTUs arranged in a horizontal direction with a pixel size of 16 × 16 and 240 pixels. Divided into parts.

Therefore, the DCT coefficient in the case where the CTU portion for 33 rows arranged in the horizontal direction with the pixel size of 64 × 64 in the video is encoded is 60 × 33 × 4 × 3 = 23760. Also, in the video, 120 rows of CTUs arranged in a horizontal direction with a pixel size of 32 × 32 and one row of CTUs arranged in a horizontal direction with a pixel size of 16 × 16 and 240 pixels. The DCT coefficient when the portion is encoded is (120 + 240) × 3 = 1080.

Then, when adjustment of the size of the video in the 2160 / P format similar to this example is not performed, the number of DCT coefficients when the entire video is encoded is 23760 + 1080 = 24840.

Therefore, according to this example, it can be seen that the size of the video is adjusted and the number of DCT coefficients is reduced from 24840 to 24480.

FIG. 8 is a flowchart showing an operation example of the decoding device 320 according to the second embodiment of the present invention. As shown in FIG. 8, first, the decoding processing unit 321 decodes the encoded video input by the receiving device 220 (step S401).

The size restoration unit 323 cuts out (extracts) the video in the range indicated by the cut range information from the video decoded by the decoding processing unit 321 based on the cut range information (step S402). Specifically, the cut-out range information indicates a range other than the video based on the dummy data in the video decoded by the decoding processing unit 321, that is, the range of the video input to the encoding device 310. Therefore, in the process of step S402, the video input to the encoding device 310 is cut (extracted) by the size restoration unit 323 (step S402).

According to the present embodiment, after the size adjustment unit 312 adjusts the number of pixels in consideration of the number of DCT coefficients, the encoding processing unit 314 performs the encoding process. Therefore, the number of DCT coefficients used for encoding can be reduced as compared with the case where such adjustment is not performed. Therefore, the minimum overhead code amount in the encoding process can be reduced.

In this embodiment, the case where a video having a format of 2160 / P is input to the encoding device 310 has been described as an example. However, the number of horizontal pixels “1920” having a format of 1080 / P and Even when a video having the number of pixels “1080” in the vertical direction is input, the number of DCT coefficients used for encoding can be reduced to 6120 by the same processing. .

As described above, this is a DCT used when a video having a format of 1080 / P and having a horizontal pixel number “1920” and a vertical pixel number “1080” is encoded without adjustment. It is clear from the fact that the number of coefficients is 7020.

Embodiment 3. FIG.
Next, a video transmission system according to a third embodiment of the present invention will be described with reference to the drawings. FIG. 9 is a block diagram illustrating a configuration example of a video transmission system (signal processing system) 500 according to the third embodiment of the present invention. As shown in FIG. 9, the video transmission system 500 according to the third embodiment of the present invention includes an encoding device 510 and a decoding device 520.

In the first embodiment of the present invention, the encoding device 110 adjusts the number of input video pixels and the aspect ratio of each pixel. In the second embodiment of the present invention, the encoding device 310 adjusts the number of pixels by adding dummy pixels to the input video.

On the other hand, the encoding device 510 of the present embodiment performs the encoding after adjusting the number of pixels of the input video and the aspect ratio of each pixel and adding a dummy pixel to the input video. Perform the process.

The video encoded by the encoding device 510 is transmitted by the transmission device 210. Also, the encoded video transmitted by the transmission device 210 is received by the reception device 220. Then, the receiving device 220 inputs the received encoded video to the decoding device 520.

Then, the decoding device 520 of the present embodiment decodes the encoded video, restores the number of pixels and the aspect ratio of the decoded video to the state before adjustment, and deletes the dummy pixels.

As shown in FIG. 9, the encoding device 510 includes a setting unit 511, a size adjustment unit 512, a pixel aspect adjustment unit 513, an encoding processing unit 514, a storage unit 515, and a cutout range setting unit 516.

The setting unit 511, the size adjustment unit 512, the pixel aspect adjustment unit 513, the encoding processing unit 514, and the cutout range setting unit 516 are realized by, for example, a CPU that executes processing according to program control and a plurality of circuits.

The setting unit 511 sets the number of pixels of the video after the adjustment by the size adjustment unit 512 based on the number of pixels of the video input to the encoding device 510.

The size adjusting unit 512 adjusts the video input to the encoding device 310 to a video having a predetermined number of pixels based on the setting result by the setting unit 511.

The cut-out range setting unit 516 includes cut-out range information that is information indicating a range excluding the dummy pixels added by the size adjusting unit 512 from the adjusted video to which the dummy pixels are added by the size adjusting unit 512. Generate.

The encoding processing unit 514 encodes an image having the number of pixels to which dummy pixels are added by the size adjusting unit 512. Then, the encoding processing unit 514 inputs the encoded video and the cut range information generated by the cut range setting unit 516 to the transmission device 210.

Information is stored in the storage unit 515 in advance. Specifically, for example, the pixel number database illustrated in FIG. 2 is stored.

As illustrated in FIG. 9, the decoding device 520 includes a decoding processing unit 521, a restoration setting unit 522, a size restoring unit 523, a pixel aspect restoring unit 524, and a storage unit 525.

The decoding processing unit 521, the restoration setting unit 522, the size restoration unit 523, and the pixel aspect restoration unit 524 are realized by, for example, a CPU that executes processing according to program control and a plurality of circuits.

The decoding processing unit 521 decodes the encoded video input by the receiving device 220. The restoration setting unit 522 sets the size of the restored video based on the number of pixels of the video decoded by the decoding processing unit 521.

The size restoration unit 523 cuts the video in the range indicated by the cut range information from the video decoded by the decoding processing unit 521 based on the cut range information.

The pixel aspect restoration unit 524 adjusts the aspect ratio of the pixel of the video whose size has been adjusted by the size restoration unit 523 based on the number of pixels of the video decoded by the decoding processing unit 521.

Information is stored in the storage unit 525 in advance. Specifically, the storage unit 525 stores, for example, a restoration database in which the restored video size set by the restoration setting unit 522 according to the number of decoded video pixels is registered.

In the restoration database, for example, information corresponding to information registered in the pixel aspect database illustrated in FIG. 3 is registered.

Next, the operation of the video transmission system 500 according to the third embodiment of the present invention will be described. FIG. 10 is a flowchart showing an operation example of the encoding apparatus 510 according to the third embodiment of the present invention.

As illustrated in FIG. 10, when video is input to the encoding device 510, the setting unit 511 stores a database in which information according to the format of the video input to the encoding device 510 is stored in the storage unit 515. And the number of pixels of the image after adjustment by the size adjustment unit 512 is set (step S501). In this example, it is assumed that a video having a format of 2160 / P (for example, a video having the number of pixels in the horizontal direction “3840” and the number of pixels in the vertical direction “2160”) is input to the encoding device 510. .

Then, for example, in response to the input of video having a format of 2160 / P to the encoding device 510, the setting unit 511 performs horizontal processing of the encoded video format “2160 / P” in the pixel number database of the storage unit 515. The number of pixels in the direction and the number of pixels in the vertical direction are read. In the example shown in FIG. 2, the encoded video format “2160 / P” includes an image having a horizontal pixel number “3840” and a vertical pixel number “2160”, a horizontal pixel number “2880”, The number of pixels in the vertical direction “2176” and the dummy data “8” to be added are included.

Therefore, the setting unit 511, for example, in accordance with the operation performed by the administrator, the horizontal pixel number “2880” and the vertical pixel number associated with the encoded video format “2160 / P” in the pixel number database of the storage unit 515. Assume that the number of pixels “2176” in the direction is read out. For example, it is assumed that the setting unit 511 reads the identifier “14” from the pixel aspect database in the storage unit 515 in accordance with an operation performed by the administrator.

Then, the setting unit 511 sets the number of pixels of the adjusted image to the number of pixels in the horizontal direction “2880” and the number of pixels in the vertical direction “2160”. The setting unit 511 sets the aspect ratio of the adjusted pixel to “4: 3”. Further, the setting unit 511 sets the number of pixels of the dummy data to “16”.

The size adjusting unit 512 adjusts the video input to the encoding device 510 to a video having a predetermined number of pixels based on the setting result by the setting unit 511 (step S502).

In this example, the setting unit 511 sets the number of pixels of the adjusted video to the number of pixels in the horizontal direction “2880” and the number of pixels in the vertical direction “2160”. Therefore, the size adjusting unit 512 thins out the video input to the encoding device 510 from the number of pixels in the horizontal direction “3840” and the number of pixels in the vertical direction “2160” to obtain the number of pixels in the horizontal direction “2880”. ”And the number of pixels in the vertical direction“ 2160 ”. Then, the number of pixels in the horizontal direction is reduced to 3/4.

In this example, the setting unit 511 sets the number of pixels of the dummy data to “16”. Therefore, the size adjustment unit 512 adds 16 pixels of dummy data arranged in the vertical direction in addition to 2160 pixels in the vertical direction across the both ends of the video in the horizontal direction. To do.

Therefore, in the video after the adjustment processing by the size adjustment unit 512, that is, the video to be encoded by the encoding processing unit 514 in the process of step S505 described later, the number of pixels in the vertical direction is 2176, and the horizontal pixels The number is 2880.

The pixel aspect adjustment unit 513 adjusts the pixel aspect ratio in the video in which the number of pixels is adjusted by the size adjustment unit 512 based on the setting result in the setting unit 511 (step S503).

In this example, the setting unit 511 sets the aspect ratio of the pixel after adjustment to “4: 3”. Therefore, the pixel aspect adjustment unit 513 adjusts the aspect ratio of the pixels in the video whose number of pixels is adjusted by the size adjustment unit 512 to “4: 3”. Accordingly, the pixels in the video whose number of pixels has been adjusted by the size adjusting unit 512 are expanded 4/3 times in the horizontal direction.

The cutout range setting unit 516 includes a cutout indicating a range other than the video based on the dummy data, that is, the range of the video input to the encoding device 510 among the videos that have been adjusted by the size adjustment unit 512 in the process of step S502. Range information is generated (step S504).

The encoding processing unit 514 encodes the video in which the number of pixels is adjusted by the size adjusting unit 512 and the pixel aspect ratio is adjusted by the pixel aspect adjusting unit 513 (step S505). Then, the encoding processing unit 514 inputs the encoded video and the cut range information generated by the cut range setting unit 516 to the transmission device 210.

The encoded video and cutout range information input to the transmission device 210 are transmitted by the transmission device 210. Also, the encoded video and cutout range information transmitted by the transmission device 210 are received by the reception device 220. Then, the receiving device 220 inputs the received encoded video and cutout range information to the decoding device 520.

In this example, the video to be encoded by the encoding processing unit 514 has a horizontal pixel count of “2880” and a vertical pixel count of “2176”. In the HEVC standard, CTU pixel sizes include 64 × 64, 32 × 32, and 16 × 16. Then, 2880 ÷ 64 = 45. Also, 2172 ÷ 64 = 34. Therefore, the video is divided into 34 rows of CTUs each having 45 pixels arranged in a horizontal direction with a pixel size of 64 × 64. Therefore, the DCT coefficient in the case where the CTU portion for 34 rows arranged in the horizontal direction with the pixel size of 64 × 64 in the video is encoded is 45 × 34 × 4 × 3 = 18360.

Therefore, the number of DCT coefficients when the entire video is encoded is 18360.

When the size of the 2160 / P format image is not adjusted as in this example, the number of pixels in the horizontal direction is “3840” and the number of pixels in the vertical direction is “2160”. Then, as described above, the number of DCT coefficients when the entire video is encoded is 23760 + 1080 = 24840.

Therefore, according to this example, it can be seen that the size of the video is adjusted and the number of DCT coefficients is reduced from 24840 to 18360.

FIG. 11 is a flowchart showing an operation example of the decoding device 520 according to the third embodiment of the present invention. As shown in FIG. 11, first, the decoding processing unit 521 decodes the encoded video input by the receiving device 220 (step S601).

Then, the restoration setting unit 522 specifies the number of pixels of the video based on the video decoded by the decoding processing unit 521 (step S602). Then, based on the number of pixels specified by the restoration setting unit 522 in step S602, the size restoration unit 523 adjusts the size of the video decoded by the decoding processing unit 521 (step S603).

Specifically, in step S603, the size restoration unit 523 cuts out (extracts) a video in a range indicated by the cut range information from the video decoded by the decoding processing unit 521 based on the cut range information, for example. ).

Also, the pixel aspect restoration unit 524 adjusts the aspect ratio of the pixels of the video decoded by the decoding processing unit 521 and extracted by the size restoration unit 523 (step S604).

That is, the video encoded by adjusting the number of pixels and the aspect ratio is decoded by the process of step S601, adjusted by the processes of steps S603 and S604, and restored.

According to this embodiment, the encoding processing unit 514 performs the encoding process after the size adjusting unit 512 and the pixel aspect adjusting unit 513 adjust the number of pixels and the aspect ratio in consideration of the number of DCT coefficients. Therefore, the number of DCT coefficients used for encoding can be reduced as compared with the case where such adjustment is not performed. Therefore, the minimum overhead code amount in the encoding process can be reduced.

In this embodiment, the case where a video having a format of 2160 / P is input to the encoding device 510 has been described as an example. However, the number of horizontal pixels “1920” having a format of 1080 / P and Even when a video having the number of pixels “1080” in the vertical direction is input, the same process can achieve the effect of reducing the number of DCT coefficients used for encoding.

Specifically, the size adjustment unit 512 decreases the number of pixels in the horizontal direction from “1920” to “1440”. Then, the number of pixels in the horizontal direction is reduced to 3/4. In addition, the size adjusting unit 512 converts the video by dummy data in which eight pixels arranged in the vertical direction in the video are arranged across both ends in the horizontal direction of the video into the video input to the encoding device 510. Append. Then, in the video after the size adjustment by the size adjustment unit 512, the number of pixels in the horizontal direction becomes “1440” and the number of pixels in the vertical direction becomes “1088”. Then, the pixel aspect adjustment unit 513 adjusts the aspect ratio of the pixels in the video whose number of pixels is adjusted by the size adjustment unit 512 to “4: 3”.

Then, the video has 17 rows of CTUs arranged in a horizontal direction with a pixel size of 64 × 64 and 22 rows of CTUs, and 34 rows of CTUs arranged in a horizontal direction with a pixel size of 32 × 32 respectively. And divided.

Then, in the video, the DCT coefficient in the case of encoding the CTU portion of 17 rows arranged in the horizontal direction with the pixel size of 64 × 64 is 22 × 17 × 4 × 3 = 4488. In addition, in the video, the DCT coefficient when coding the 34 rows of CTU portions arranged in the horizontal direction with a pixel size of 32 × 32 is 1 × 34 × 3 = 102.

Then, the number of DCT coefficients when the size-adjusted image is encoded by the size adjusting unit 512 so that the number of pixels in the horizontal direction is “1440” and the number of pixels in the vertical direction is “1088”. Is 4488 + 102 = 4590.

On the other hand, an image that has not been processed by the size adjustment unit 512 and has 1080 pixels in the vertical direction and 1920 pixels in the horizontal direction has a pixel size of 64 × 64 and 30 in the horizontal direction. 16 rows of CTUs arranged in a row, 60 rows of CTUs arranged in a horizontal direction with a pixel size of 32 × 32, and 120 pieces of CTUs arranged in a horizontal direction with a pixel size of 16 × 16 It is divided into a CTU portion for one row and a CU portion for one row arranged in the horizontal direction with 8 × 8 pixel size.

Then, when a video having 1080 vertical pixels and 1920 horizontal pixels is encoded, 30 rows of 16 pixels arranged in a horizontal direction with a 64 × 64 pixel size are provided. The number of DCT coefficients when the CTU part is encoded is 30 × 16 × 4 × 3 = 5760. In addition, 60 CTU portions arranged in a horizontal direction with a pixel size of 32 × 32, and CTU portions of one row arranged in a horizontal direction with a pixel size of 16 × 16, The number of DCT coefficients in the case of coding 240 CU portions arranged in a row in the horizontal direction with an 8 × 8 pixel size is (60 + 120 + 240) × 3 = 1260.

Therefore, the number of DCT coefficients when a video having 1080 pixels in the vertical direction and 1920 pixels in the horizontal direction is encoded is 5760 + 1260 = 7020.

Therefore, even when a video having a format of 1080 / P and having a horizontal pixel count of “1920” and a vertical pixel count of “1080” is input, the processing according to the present embodiment enables encoding. The effect is that the number of DCT coefficients used can be reduced from 7020 to 4590.

Embodiment 4 FIG.
Next, a fourth embodiment of the present invention will be described with reference to the drawings. FIG. 12 is a block diagram illustrating a configuration example of the signal processing device according to the fourth embodiment of the present invention.

As shown in FIG. 12, the signal processing apparatus 11 according to the fourth embodiment of the present invention includes a storage unit (storage unit) 15, a pixel number adjustment unit (pixel number adjustment unit) 12, and an encoding unit (encoding). Means) 14.

Note that the signal processing device 11 is, for example, the encoding device 110 in the first embodiment shown in FIG. 1, the encoding device 310 in the second embodiment shown in FIG. 6, or the third embodiment shown in FIG. This corresponds to the encoding device 510 in FIG.

The storage unit 15 corresponds to the storage unit 315 in the second embodiment shown in FIG. 6 and the storage unit 515 in the third embodiment shown in FIG.

The pixel number adjusting unit 12 corresponds to the size adjusting unit 312 in the second embodiment shown in FIG. 6 and the size adjusting unit 512 in the third embodiment shown in FIG.

The encoding unit 14 corresponds to the encoding processing unit 314 in the second embodiment shown in FIG. 6 and the encoding processing unit 514 in the third embodiment shown in FIG.

The storage unit 15 stores set pixel number information indicating a predetermined number of pixels according to the discrete cosine transform process. The set pixel number information corresponds to, for example, information registered in the pixel number database.

The pixel number adjustment unit 12 adjusts the number of pixels constituting the input video according to the number of pixels indicated by the set pixel number information stored in the storage unit 15.

The encoding unit 14 performs an encoding process including a discrete cosine transform process on the video in which the pixel number adjusting unit 12 has adjusted the number of pixels.

The pixel number adjustment unit 12 executes a process of adding additional pixels to the input video according to the number of pixels indicated by the set pixel number information.

According to the present embodiment, the pixel number adjusting unit 12 adjusts the number of pixels constituting the input video according to the number of pixels indicated by the set pixel number information stored in the storage unit 15. And the encoding part 14 performs the encoding process including the process of a discrete cosine transform to the image | video in which the pixel number adjustment part 12 adjusted the number of pixels.

Therefore, the size of the video can be adjusted to reduce the number of DCT coefficients, and the video can be encoded in consideration of the minimum overhead code amount.

The present invention has been described above with reference to the embodiments, but the present invention is not limited to the above embodiments. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.

This application claims priority based on Japanese Patent Application No. 2018-023959 filed on Feb. 14, 2018, the entire disclosure of which is incorporated herein.

DESCRIPTION OF SYMBOLS 11 Signal processing apparatus 12 Pixel number adjustment part 14 Encoding part 15 Memory | storage part 100,300,500 Video transmission system 110,310,510 Encoding apparatus 111,311,511 Setting part 112,312,512 Size adjustment part 113,513 Pixel aspect adjustment unit 114, 314, 514 Encoding processing unit 115, 125, 315, 515, 525 Storage unit 120, 320, 520 Decoding device 121, 321, 521 Decoding processing unit 122, 522 Restoration setting unit 123, 323, 523 Size restoration unit 124, 524 Pixel aspect restoration unit 210 Transmission device 220 Reception device 313, 516 Cutout range setting unit 524 Pixel aspect restoration unit

Claims (8)

1. Storage means for storing set pixel number information indicating a predetermined number of pixels according to discrete cosine transform processing;
   Pixel number adjusting means for adjusting the number of pixels constituting the input video according to the number of pixels indicated by the set pixel number information stored in the storage means;
   Coding means for performing coding processing including processing of the discrete cosine transform on the video in which the pixel number adjusting means has adjusted the number of pixels;
   The pixel number adjusting means includes
   A signal processing device that performs processing for adding additional pixels to the input video according to the number of pixels indicated by the set pixel number information.
2. The pixel number adjusting means includes
   The signal according to claim 1, wherein range information indicating an extraction range for extracting a video including pixels other than the pixels added in the adding process is generated from the video that has been subjected to the decoding process according to the encoding process. Processing equipment.
3. The pixel number adjusting means includes
   In accordance with the number of pixels indicated by the set pixel number information, a process of thinning out some of the pixels constituting the input video is executed,
   The signal processing apparatus according to claim 1, wherein the aspect ratio of the remaining pixels among the pixels constituting the input video is adjusted according to the thinning process.
4. The pixel number adjusting means includes
   The signal processing device according to claim 3, wherein in the thinning-out process, a part of the pixels arranged in the horizontal direction or the pixels arranged in the vertical direction is thinned out.
5. The signal processing device according to any one of claims 1 to 4, wherein the storage unit stores the set pixel number information indicating the number of pixels corresponding to a unit of processing of the discrete cosine transform. .
6. A signal processing device according to any one of claims 1 to 5,
   A signal processing system comprising: a decoding processing device that performs a decoding process according to the encoding process.
7. The input image is displayed in accordance with the number of pixels indicated by the set pixel number information stored in the storage means in which the preset pixel number information indicating the predetermined number of pixels corresponding to the discrete cosine transform processing is stored. Adjust the number of pixels
   Performing an encoding process including a process of the discrete cosine transform on the video in which the number of pixels is adjusted;
   When adjusting the number of pixels,
   A signal processing method, wherein an additional pixel is added to the input video according to the number of pixels indicated by the set pixel number information.
8. On the computer,
   The input image is displayed in accordance with the number of pixels indicated by the set pixel number information stored in the storage means in which the preset pixel number information indicating the predetermined number of pixels corresponding to the discrete cosine transform processing is stored. A pixel number adjustment process for adjusting the number of constituent pixels;
   An encoding process for performing an encoding process including a process of the discrete cosine transform on the video in which the number of pixels is adjusted in the pixel number adjustment process;
   In the pixel number adjustment process,
   A storage medium storing a signal processing program for adding additional pixels to the input video according to the number of pixels indicated by the set pixel number information.

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