WO2015059880A1

WO2015059880A1 - Motion compensation method, image encoding method, image decoding method, image encoding device and image decoding device

Info

Publication number: WO2015059880A1
Application number: PCT/JP2014/005072
Authority: WO
Inventors: 寿郎笹井; 健吾寺田
Original assignee: パナソニックインテレクチュアルプロパティコーポレーションオブアメリカ
Priority date: 2013-10-22
Filing date: 2014-10-06
Publication date: 2015-04-30

Abstract

A motion compensation method comprises: a complementing step of complementing the pixel values of a reference block when motion compensation is performed for a target block, which is included in a plurality of tiles, by use of a prediction mode using the motion vectors of peripheral blocks of the target block and further when the motion vectors of the peripheral blocks refer to the reference block included in tiles different from the target tiles in which the target block is included; and a motion compensating step of performing the aforementioned motion compensation by use of the aforementioned pixel values as complemented.

Description

Motion compensation method, image encoding method, image decoding method, image encoding device, and image decoding device

The present invention relates to a motion compensation method, an image encoding method, and an image decoding method.

Currently, the HEVC (High Efficiency Video Coding) method (see Non-Patent Document 1) is being studied as a new image coding standard.

In such an image encoding method and image decoding method, it is desired that the encoded bit stream can be appropriately decoded in the image decoding apparatus.

An object of the present disclosure is to provide an image encoding method, an image decoding method, or a motion compensation method capable of appropriately decoding an encoded bitstream in an image decoding device.

In order to achieve the above object, a motion compensation method according to an aspect of the present disclosure performs motion compensation on a target block included in a plurality of tiles using a prediction mode that uses motion vectors of blocks around the target block. A motion compensation method to be performed, wherein when the motion vector of the surrounding block refers to a reference block included in a tile different from the target tile including the target block, a complement that complements a pixel value of the reference block And a motion compensation step for performing the motion compensation using the complemented pixel values.

In addition, the motion image encoding method according to an aspect of the present disclosure includes a dividing step of dividing an image into a plurality of tiles, and target blocks included in the plurality of tiles are converted into motion vectors of blocks around the target block. Encoding using one of a plurality of prediction modes including a prediction mode to be used, and in the encoding step, the target block is included in a tile different from the target tile including the target block. Encoding is performed without using a motion vector that refers to the block to be recorded.

These general or specific aspects may be realized by a system, a method, an integrated circuit, a computer program, or a recording medium such as a computer-readable CD-ROM. The system, method, integrated circuit, computer program Also, any combination of recording media may be realized.

According to the present disclosure, it is possible to provide an image encoding method, an image decoding method, or a motion compensation method capable of appropriately decoding an encoded bitstream in an image decoding device.

FIG. 1A is a diagram for explaining a motion compensation limit tile. FIG. 1B is a diagram for explaining a motion compensation limit tile. FIG. 2 is a diagram for explaining the process of generating the decimal pixel at the tile boundary. FIG. 3A is a diagram for explaining a derivation process of a skip / merge vector. FIG. 3B is a diagram for explaining skip / merge vector derivation processing. FIG. 3C is a diagram for explaining the derivation process of the skip / merge vector. FIG. 4 is a block diagram of the image coding apparatus according to Embodiment 1. FIG. 5 is a flowchart of the image encoding process according to the first embodiment. FIG. 6 is a flowchart of a modification of the image encoding process according to the first embodiment. FIG. 7 is a block diagram of an image decoding apparatus according to the second embodiment. FIG. 8 is a flowchart illustrating an example of motion compensation processing. FIG. 9 is a flowchart of the image decoding process according to the second embodiment. FIG. 10 is a diagram for explaining a complementing process for pixels outside the area according to the second embodiment. FIG. 11 is a flowchart of the motion compensation process according to the second embodiment. FIG. 12 is a diagram illustrating a syntax example of the encoded bitstream. FIG. 13 is a flowchart illustrating an example of syntax processing. FIG. 14A is a diagram illustrating a syntax example of an encoded bitstream according to Embodiment 3. FIG. 14B is a diagram illustrating another example of the syntax of the encoded bitstream according to Embodiment 3. FIG. 14C is a diagram illustrating another example of the syntax of the encoded bitstream according to Embodiment 3. FIG. 15 is a flowchart of image decoding processing according to the third embodiment. FIG. 16 is a diagram for explaining special processing according to the third embodiment. FIG. 17 is an overall configuration diagram of a content supply system that implements a content distribution service. FIG. 18 is an overall configuration diagram of a digital broadcasting system. FIG. 19 is a block diagram illustrating a configuration example of a television. FIG. 20 is a block diagram illustrating a configuration example of an information reproducing / recording unit that reads and writes information from and on a recording medium that is an optical disk. FIG. 21 is a diagram illustrating a structure example of a recording medium that is an optical disk. FIG. 22A illustrates an example of a mobile phone. FIG. 22B is a block diagram illustrating a configuration example of a mobile phone. FIG. 23 is a diagram showing a structure of multiplexed data. FIG. 24 is a diagram schematically showing how each stream is multiplexed in the multiplexed data. FIG. 25 is a diagram showing in more detail how the video stream is stored in the PES packet sequence. FIG. 26 is a diagram illustrating the structure of TS packets and source packets in multiplexed data. FIG. 27 is a diagram illustrating a data structure of the PMT. FIG. 28 is a diagram illustrating an internal configuration of multiplexed data information. FIG. 29 shows the internal structure of stream attribute information. FIG. 30 shows steps for identifying video data. FIG. 31 is a block diagram illustrating a configuration example of an integrated circuit that realizes the moving picture coding method and the moving picture decoding method according to each embodiment. FIG. 32 is a diagram showing a configuration for switching the drive frequency. FIG. 33 is a diagram showing steps for identifying video data and switching between driving frequencies. FIG. 34 is a diagram showing an example of a look-up table in which video data standards are associated with drive frequencies. FIG. 35A is a diagram illustrating an example of a configuration for sharing a module of a signal processing unit. FIG. 35B is a diagram illustrating another example of a configuration for sharing a module of a signal processing unit.

(Knowledge that became the basis of the present invention)
The present inventor has found that the following problems occur with respect to the prior art.

H. In the ITU-T standard called 26x or the ISO / IEC standard called MPEG-x, one image is divided into a plurality of units called tiles as shown in FIG. 1A. Each tile cannot reference other tiles in the image in which the tile is included. For example, when the tile 2 is an object to be encoded or decoded, the tile 2 cannot refer to the tile 1. However, when images different in time are referred to, a target block that is an encoding or decoding target can refer to a tile other than the tile 2. For example, the left image shown in FIG. 1A is an image at time t−1, the right image is an image at time t, and these images are temporally different images. FIG. 1A is a diagram illustrating an example in which a reference block belonging to tile 3 at time t−1 is used as a reference image when a target block belonging to tile 2 at time t is processed.

On the other hand, when such a reference is allowed, there are the following problems. For example, when the image size is very large, parallel processing is performed in which tiles are processed by different LSIs. However, as described above, in order to allow reference to other tiles included in images having different times, each LSI writes an image generated by the LSI into one large memory, and the plurality of LSIs write the image. Need to share memory. In this case, it is necessary to synchronize separate LSIs, and there is a problem that the amount of processing for synchronization processing increases.

Therefore, Non-Patent Document 1 describes a method for describing in an encoded stream information indicating that reference to other tiles included in images having different times is prohibited. In this case, as shown in FIG. 1B, the target block needs to refer to the reference block in the same tile (tile 2) even in the temporally different image (frame (t-1)). This eliminates the need for each LSI to output a reference image to a shared memory when parallel processing is performed by a plurality of LSIs. In the following, tiles having such restrictions are referred to as MC restricted tiles.

However, the present inventor has found that there are the following problems in order to realize this.

(1) Even when referring to an area within the same tile, different tiles may be referred to in order to calculate a decimal pixel that is a pixel with decimal precision.

A method for generating a decimal pixel will be described with reference to FIG. FIG. 2A shows a reference pixel of a filter for generating a pixel value at a position shifted by ¼ pixel from the leftmost tile boundary. Integer pixels connected by lines are referenced. In this case, three pixels outside the tile area are referred to.

(B) of FIG. 2 shows a reference pixel of a filter for generating a pixel value at a position shifted by 1/2 pixel from the leftmost tile boundary. In this case, three pixels outside the tile area are referred to. FIG. 2C shows a reference pixel of a filter for generating a pixel value at a position shifted by 3/4 pixel from the leftmost tile boundary. In this case, two pixels outside the tile area are referred to.

In the same way, the outside of the tile area is not referred to on the right side of the position shifted by 2/4 and 3/4 pixels from the leftmost tile boundary shown in FIG. For this reason, when referring to image signals at different times, in order to realize a reference that does not cross tiles as described above, from integer pixels in the same tile or 2 and 3/4 pixels from the tile boundary It is necessary to refer to the inner decimal pixel. However, switching such processing at the screen edge results in an increase in processing amount and an increase in circuit scale.

(2) There is a mode called a skip mode and a merge mode in which motion vectors of surrounding processed blocks are reused. Here, the motion vector is information indicating a relative position between the target block and the reference block, and includes, for example, a horizontal component and a vertical component. When this mode is selected, even if the block to be reused does not reference across the tile boundary, the reference across the boundary is performed when the motion vector is reused in the target block There is. Therefore, the image encoding device and the image decoding device need to confirm this.

Hereinafter, regions to be referred to when deriving motion vectors used in the skip mode and merge mode (hereinafter, skip / merge vectors) will be described with reference to FIGS. 3A to 3C.

FIG. 3A is a diagram showing a case where a motion vector of an adjacent block in the screen is referred to. In the derivation of the skip / merge vector of the target block X, the motion vectors of the blocks A0, A1, B0, B1, and B2 located around the target block X may be referred to.

There is also a method of referring to motion vectors of pictures that differ in time. As shown in FIG. 3B, the motion vector of the block C located at the same position as the target block X of the temporally different picture or the block H located at the lower right of the block C is referred to.

FIG. 3C is a diagram illustrating an example in which the target block X located at the tile boundary reuses the motion vector MV0 of the block B0 at the upper right of the target block X. As shown in FIG. 3C, when processing the block B0, the motion vector MV0 does not cross the tile boundary, and the reference block R0 in the same tile (tile 2) as the block B0 is referred to. On the other hand, when the motion vector MV0 is reused in the target block X, the motion vector MV0 straddles the tile boundary, and the reference block R1 of another tile (tile 1) is referred to. Since such a case occurs, the image encoding device or the image decoding device needs to confirm this. However, checking whether the motion vector crosses the tile boundary at the time of all motion predictions leads to an increase in processing amount and an increase in circuit scale.

Also, as processing of these tile edges, processing different from the processing of the screen edges of the image signal is necessary. This is because, in the case of the screen edge, the process in the case where there is no adjacent pixel is described in Non-Patent Document 1, but the tile edge process in which the motion reference is restricted is not defined. As a result, the processing as described above is required.

As described above, the present inventor has found that there is a problem that special area edge processing has to be performed when each of the areas divided into tiles is processed in parallel.

More specifically, processing is necessary for the image encoding device or the image decoding device to perform parallel processing (parallel encoding and decoding) on the target image signal. Since the processing time increases due to this processing, it is difficult to realize high-speed processing. Alternatively, there is a problem that it is necessary to increase the circuit scale in order to perform this processing at high speed.

In the following embodiments, an image encoding device or an image decoding device capable of parallel processing, which can encode or decode a target image signal at high speed, will be described. .

In the following embodiment, an image encoding method, an image decoding method, or a motion compensation method that can reduce the processing amount in the image encoding device or the image decoding device will be described.

A motion compensation method according to an aspect of the present invention is a motion compensation method for performing motion compensation on a target block included in a plurality of tiles using a prediction mode using a motion vector of a block around the target block, When the motion vector of the surrounding block refers to a reference block included in a tile different from the target tile in which the target block is included, a complementing step for complementing pixel values of the reference block and the complemented pixel A motion compensation step of performing the motion compensation using a value.

According to this, when the pixel value of another tile is referred to, the motion compensation method complements and generates the pixel value of the other tile. Thereby, motion compensation can be performed without using pixel values of other tiles. Thereby, the image decoding apparatus can appropriately decode the encoded bit stream.

For example, in the complementing step, the pixel value of the reference block may be supplemented using a pixel value included in the target block.

According to this, the motion compensation method can appropriately complement and generate pixel values of other tiles.

For example, in the complementing step, the pixel value of the pixel that is included in the target block and that is closest to the reference block is copied to a plurality of pixel values that are included in the reference block. May be supplemented.

According to this, in the motion compensation method, for example, pixel values of other tiles can be complementarily generated by a process similar to a process when a pixel value outside the screen is referred to. Thereby, an increase in circuit scale can be suppressed.

For example, in the complementing step, when the target block and the reference block are adjacent to each other, the pixel values of a plurality of pixels included in the target block are folded around the adjacent boundary as an axis, and a plurality of pixels included in the reference block are included. The pixel value of the reference block may be complemented by copying to the pixel value.

According to this, the motion compensation method can improve the image quality when the video gradually changes, such as a gradation image.

For example, in the complementing step, an average value of a plurality of pixel values included in the target block may be calculated, and the average value may be supplemented as a plurality of pixel values included in the reference block.

According to this, the motion compensation method can suppress degradation of image quality.

The image coding method according to an aspect of the present invention is an image coding method using the motion compensation method, wherein the motion vector of the surrounding block is included in the tile different from the target tile. Information for specifying that the reference block is referred to is generated, and an encoded bit stream including the information is generated.

The image coding method according to an aspect of the present invention uses a dividing step of dividing an image into a plurality of tiles, and uses a motion vector of a block around the target block for the target block included in the plurality of tiles. Encoding using one of a plurality of prediction modes including a prediction mode, and in the encoding step, the target block is included in a tile different from the target tile including the target block. Encode without using motion vectors that reference blocks.

According to this, the image encoding method can generate an encoded bitstream that is encoded without using a motion vector that refers to another tile. Thereby, the image decoding apparatus can appropriately decode the encoded bit stream. In addition, since it is not necessary to perform special processing in the image decoding apparatus, the processing amount in the image decoding apparatus can be reduced.

For example, in the encoding step, it is determined whether or not the motion vector of the surrounding block refers to a block included in the tile different from the target tile, and the motion vector of the surrounding block is the target. When it is determined that the block included in the tile different from the tile is referred to, the target block may be encoded using a motion vector other than the motion vector of the surrounding block.

According to this, the image coding method determines whether or not the motion vector refers to another tile, and does not use the motion vector when referring to the tile. Thereby, since the said image coding method can prohibit use of the motion vector which refers another tile appropriately, the fall of coding efficiency can be suppressed.

For example, in the encoding step, it is determined whether or not the target block is located within a certain value from the tile boundary, and when it is determined that the target block is located within the certain value from the tile boundary, The target block may be encoded using a prediction mode other than the skip mode and the merge mode, which are modes in which the motion vector of the block is used as it is.

According to this, the image encoding method determines whether or not the motion vector refers to another tile based on whether or not the target block is located within a certain value from the tile boundary. Thereby, the processing amount of an image coding apparatus can be reduced.

The image decoding method according to an aspect of the present invention decodes the encoded bitstream generated by the image encoding method.

According to this, the image decoding method decodes an encoded bitstream that is encoded without using a motion vector that refers to another tile. Thereby, the image decoding apparatus can appropriately decode the encoded bit stream. In addition, since it is not necessary to perform special processing in the image decoding apparatus, the processing amount in the image decoding apparatus can be reduced.

According to this, the processing amount of the image decoding apparatus can be reduced, or the image quality of the decoded image can be improved.

An image encoding device according to an aspect of the present invention includes a processing circuit and a storage device accessible from the processing circuit, and the processing circuit executes the motion compensation method using the storage device. To do.

According to this, when the pixel value of another tile is referred to, the image encoding device complementarily generates the pixel value of the other tile. Thereby, motion compensation can be performed without using pixel values of other tiles. Further, the image decoding apparatus performs the same processing, so that the encoded bitstream can be appropriately decoded.

An image decoding device according to one embodiment of the present invention includes a processing circuit and a storage device accessible from the processing circuit, and the processing circuit executes the motion compensation method using the storage device. .

According to this, when the pixel value of another tile is referred to, the image decoding apparatus complements and generates the pixel value of the other tile. Thereby, motion compensation can be performed without using pixel values of other tiles. Thereby, the image decoding apparatus can appropriately decode the encoded bit stream.

An image encoding device according to an aspect of the present invention includes a processing circuit and a storage device accessible from the processing circuit, and the processing circuit performs the image encoding method using the storage device. Execute.

According to this, the image encoding apparatus can generate an encoded bitstream that is encoded without using a motion vector that refers to another tile. Thereby, the image decoding apparatus can appropriately decode the encoded bit stream. In addition, since it is not necessary to perform special processing in the image decoding apparatus, the processing amount in the image decoding apparatus can be reduced.

An image decoding device according to an aspect of the present invention includes a processing circuit and a storage device accessible from the processing circuit, and the processing circuit executes the image decoding method using the storage device. .

According to this, the image decoding apparatus decodes an encoded bitstream that is encoded without using a motion vector that refers to another tile. Thereby, the image decoding apparatus can appropriately decode the encoded bit stream. In addition, since it is not necessary to perform special processing in the image decoding apparatus, the processing amount in the image decoding apparatus can be reduced.

Also, an image encoding / decoding device according to an aspect of the present invention includes the image encoding device and the image decoding device.

Note that these comprehensive or specific modes may be realized by a system, a method, an integrated circuit, a computer program, or a recording medium such as a computer-readable CD-ROM, and the system, method, integrated circuit, and computer program. Also, any combination of recording media may be realized.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

It should be noted that each of the embodiments described below shows a comprehensive or specific example. The numerical values, shapes, materials, constituent elements, arrangement positions and connecting forms of the constituent elements, steps, order of steps, and the like shown in the following embodiments are merely examples, and are not intended to limit the present invention. In addition, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims indicating the highest concept are described as optional constituent elements.

(Embodiment 1)
In the present embodiment, an image encoding method for generating an encoded stream that realizes parallel processing will be described. In the present embodiment, the bitstream includes information that allows the image encoding device to easily perform parallel processing. That is, a block included in a tile which is a region into which a picture is divided refers only to pixels in the same tile included in a picture at the same time or different times in motion prediction and motion compensation processing.

First, the configuration of the image encoding device 100 according to the present embodiment will be described. FIG. 4 is a block diagram illustrating a configuration example of the image encoding device 100 according to the present embodiment.

The image encoding device 100 generates an encoded signal 129 (encoded bit stream) by compressing and encoding the input image 121. For example, the input image 121 is input to the image encoding device 100 for each block. The image encoding device 100 generates an encoded signal 129 by performing transformation, quantization, and variable length encoding on the input image 121 that has been input.

4 includes a subtractor 101, a transform quantization unit 102, an entropy coding unit 103, an inverse quantization inverse transform unit 104, an adder 105, and a deblocking processing unit 106. , A memory 107, an intra prediction unit 108, a motion compensation unit 109, a motion detection unit 110, and a changeover switch 112.

The subtractor 101 calculates a residual signal 122 (also referred to as a prediction error or a difference signal) that is a difference between the input image 121 and the prediction signal 127.

The transform quantization unit 102 transforms the spatial domain residual signal 122 into a frequency domain transform coefficient. For example, the transform quantization unit 102 generates a transform coefficient by performing DCT (Discrete Cosine Transform) transform on the residual signal 122. Further, the transform quantization unit 102 generates a quantized coefficient 123 by quantizing the transform coefficient.

The entropy encoding unit 103 generates an encoded signal 129 by performing variable length encoding on the quantization coefficient 123. In addition, the entropy encoding unit 103 encodes the motion data 128 (for example, a motion vector) detected by the motion detection unit 110 and includes the obtained signal in the encoded signal 129 for output.

The inverse quantization inverse transform unit 104 restores the residual signal 124 by inversely transforming the restored transform coefficient. The restored residual signal 124 does not match the residual signal 122 generated by the subtractor 101 because a part of the information is lost due to quantization. That is, the restored residual signal 124 includes a quantization error.

The adder 105 generates the local decoded image 125 by adding the restored residual signal 124 and the prediction signal 127.

The deblocking processing unit 106 generates a local decoded image 126 by performing a deblocking filter process on the local decoded image 125.

The memory 107 is a memory for storing a reference image used for motion compensation. Specifically, the memory 107 stores the local decoded image 126 after the deblocking filter process is performed. The memory 107 also stores processed motion data.

The intra prediction unit 108 generates a prediction signal (intra prediction signal) by performing intra prediction. Specifically, the intra prediction unit 108 performs intra prediction by referring to images around the encoding target block (the input image 121) in the local decoded image 125 generated by the adder 105, so that intra prediction is performed. Generate a signal.

The motion detection unit 110 detects motion data 128 (for example, a motion vector) between the input image 121 and the reference image stored in the memory 107. In addition, the motion detection unit 110 also performs calculations regarding the skip vector and the merge vector using the encoded motion data.

The motion compensation unit 109 generates a prediction signal (inter prediction signal) by performing motion compensation based on the detected motion data 128.

The changeover switch 112 selects either the intra prediction signal or the inter prediction signal, and outputs the selected signal to the subtracter 101 and the adder 105 as the prediction signal 127.

With the above configuration, the image encoding apparatus 100 according to the present embodiment compresses and encodes image data.

Next, the operation of the image encoding device 100 will be described. FIG. 5 is a flowchart illustrating an outline of processing when the motion prediction mode is determined by the image coding apparatus 100 according to the present embodiment.

In the process shown in FIG. 5, the reuse of motion vectors is limited. First, the motion detection unit 110 acquires motion information that is a skip / merge vector candidate from the memory 107 (S101). Also, the motion detection unit 110 derives skip / merge vector candidates from, for example, adjacent blocks illustrated in FIGS. 3A and 3B. Specifically, the motion detection unit 110 uses the method shown in Non-Patent Document 1 as a skip vector derivation method and a merge vector derivation method.

Next, the motion detection unit 110 determines whether or not the acquired skip / merge vector crosses the tile boundary (S102). Specifically, the motion detection unit 110 converts the start point of the motion vector of the adjacent block into the coordinates of the current target block, and determines whether the reference destination of the converted motion vector is another tile. In addition, even when the reference destination of the motion vector after conversion is not another tile, the motion detection unit 110 has a reference destination of the motion vector that is less than 2 and 3/4 pixels from the tile boundary. If it is a decimal pixel, it may be determined that the converted motion vector straddles the tile boundary. In other words, the skip / merge vector crosses the tile boundary is, in other words, the case where the skip / merge vector refers to another tile (when the predicted image is generated using the pixel value of the other tile).

When the converted motion vector does not cross the tile boundary (NO in S102), the motion detection unit 110 calculates the cost when using the motion vector (S103). Here, the cost is, for example, a weighted addition between a code amount for indicating the skip / merge vector, and a difference between a predicted image (an image referred to by the vector) and an input image to be encoded, or the like. The cost value calculated by In addition, a cost value when motion detection is performed is calculated, and a plurality of cost values are compared to determine an optimal motion prediction mode. Further, when the cost value is defined in this way, the optimum motion prediction mode is when the cost value is minimized. Note that the cost calculation method is not limited to this, but for the sake of simplicity, the case where the cost value is minimized is described as the optimal motion prediction mode.

On the other hand, when it is determined that the skip / merge vector exceeds the tile boundary (YES in S102), the motion detection unit 110 determines not to use the skip / merge vector (S104). For example, the motion detection unit 110 sets the cost value of the skip / merge vector to the maximum value so that the skip / merge vector is not used. Note that the set value does not need to be the maximum value, and may be an arbitrary value as long as it is a value that is not selected as the optimum value. Further, the method of prohibiting the use of the skip / merge vector may be other than the method of changing the cost value.

If the processing for all skip / merge vector candidates acquired in step S101 has not been completed (NO in S105), the motion detection unit 110 performs cost calculation for the next skip / merge vector candidates (S102 to S102). S104).

When the cost calculation has been completed for all skip / merge vector candidates (YES in S105), the motion detection unit 110 performs motion detection on the target block and calculates a cost value for the motion detection (S106). Note that the motion detection search range at this time is a range that does not exceed the tile boundary. For decimal pixels, less than 2 and 3/4 pixels from the boundary are set outside the search range.

Finally, the motion detection unit 110 determines the motion prediction mode to be used as the motion prediction mode for the minimum cost value among all the calculated cost values (S107).

In this way, the motion detection unit 110 can eliminate the reference of pixel data between tiles including pictures at different times by determining whether or not the skip / merge vector crosses the tile boundary. Note that this flowchart is an example, and the processing amount can be further reduced by further modification.

For example, in the process illustrated in FIG. 5, in the determination of whether to cross the tile boundary, the motion detection unit 110 determines whether the reference destination is less than 2 and 3/4 pixels from the boundary when the reference destination is a decimal pixel. In this case, since it is necessary to determine whether or not the reference destination is a decimal pixel every time, the circuit scale may increase.

On the other hand, regardless of whether the reference destination is a decimal pixel, the motion detection unit 110 determines whether the reference destination is less than 3 pixels from the tile boundary, and when the reference destination is less than 3 pixels from the tile boundary. It may be determined that the tile boundary is crossed. In this case, for example, when the integer pixel at the same position as the target block is a reference destination (vector (0, 0)), the motion detection unit 110 specifically permits the vector (0, 0). May be. As a result, the case where the reference destination is an integer pixel and is shifted by 1 or 2 pixels from the target block is excluded. That is, the motion detection unit 110 may determine that the tile boundary crosses when the reference destination is less than 3 pixels from the tile boundary and the motion vector is other than (0, 0). Thereby, degradation of encoding efficiency can be suppressed. In general, since the same position (vector (0, 0)) can be easily processed, deterioration of the coding efficiency can be suppressed by the above method while reducing the processing amount.

A modified example for further reducing the processing amount will be described with reference to FIG. FIG. 6 is a flowchart of a modification of the process when determining the motion prediction mode by the image coding apparatus 100 according to the present embodiment.

In the process shown in FIG. 6, first, the motion detection unit 110 confirms whether or not the target block is located at the boundary of the MC restriction tile (S121). Specifically, the motion detection unit 110 determines that the target block is located at the boundary of the MC restricted tiles when the target block is within a certain number of blocks from the boundary of the MC restricted tiles. Here, for example, the block may be a unit block of an encoding process called an encoding block, or may be a block of a unit called an LCU (maximum encoding block) or CTB (encoding tree block). Good.

If the target block is not located at the tile boundary (NO in S122), the motion detection unit 110 extracts skip / merge vector candidates as in step S101 (S123). Next, the motion detection unit 110 calculates a cost value in the same manner as in step S103 (S124), and confirms whether all candidates have been confirmed in the same manner as in step S105 (S125).

On the other hand, when the target block is located at the tile boundary (YES in S122), the motion detection unit 110 skips steps S123 to S125, and does not extract skip / merge vector candidates and calculate the cost value.

Next, the motion detection unit 110 performs motion detection as in step S106 (S126), and determines the motion prediction mode as in step S107 (S127).

The above processing eliminates the need for boundary determination for each block, so the processing amount can be reduced as compared with FIG.

Note that the motion detection unit 110 may calculate the cost value only when the target block is located at the tile boundary (YES in S122) and only when the (0, 0) vector is a candidate. As a result, the amount of calculation increases slightly, but as described above, the vector (0, 0) can be easily processed, and thus the amount of processing increases little.

By performing the above processing, for example, when a plurality of tiles are processed in parallel by an independent encoding or decoding circuit, high-speed processing can be realized.

As described above, the image coding apparatus 100 according to the present embodiment divides an image into a plurality of tiles, and uses the motion vectors of blocks around the target block for target blocks included in the plurality of tiles. Encoding is performed using one of a plurality of prediction modes including a mode. For example, the plurality of prediction modes include a merge mode or a skip mode. The merge mode and the skip mode are prediction modes that use the motion vectors of the blocks around the target block as they are. That is, in the merge mode and the skip mode, the motion vector difference is not encoded. Note that processing such as time scaling is also used in the merge mode and the skip mode. In addition, the image encoding device 100 encodes the target block without using a motion vector that refers to a block included in a tile different from the target tile including the target block. Here, as described above, the motion vector that refers to a block included in a tile different from the target tile including the target block is a motion vector whose reference destination is another tile, and the reference destination is It is at least one of motion vectors that are decimal pixels that refer to integer pixels of other blocks.

Specifically, as illustrated in FIG. 5, the image encoding device 100 determines whether or not to refer to a block included in a tile whose motion vector of surrounding blocks is different from the target tile (S102). Also, when it is determined that the motion vector of the surrounding block refers to a block included in a tile different from the target tile (YES in S102), the image coding apparatus 100 uses a motion vector other than the motion vector ( The target block is encoded (without using the motion vector) (S104).

Or, as shown in FIG. 6, the image coding apparatus 100 determines whether or not the target block is located within a certain value from the tile boundary (S121). When it is determined that the target block is located within a certain value from the tile boundary (YES in S122), the image coding apparatus 100 has a prediction mode other than a prediction mode (merge mode or skip mode) that uses motion vectors of surrounding blocks. (Without using a prediction mode that uses motion vectors of surrounding blocks) is used to encode the target block.

As described above, the image encoding device 100 can perform processing of the MC restricted tile boundary at high speed. Thereby, the image coding apparatus 100 and the image coding method can generate a bit stream that can be processed at high speed in the image decoding apparatus.

(Embodiment 2)
In the present embodiment, an image decoding method for decoding an encoded stream that realizes parallel processing will be described. In the present embodiment, an image decoding method for decoding an encoded bitstream generated by the image encoding apparatus 100 according to Embodiment 1 will be described.

Furthermore, in this embodiment, even when a bitstream including a signal that is referred to across a tile boundary is received, an image decoding method and an image decoding apparatus that can realize parallel decoding while suppressing image quality degradation Will be described.

First, the configuration of the image decoding apparatus 200 according to the present embodiment will be described. FIG. 7 is a block diagram showing an example of the configuration of the image decoding apparatus 200 according to the present embodiment.

The image decoding apparatus 200 generates a decoded image 225 from the encoded signal 221 obtained by compressing and encoding the image. Here, the encoded signal 221 is, for example, the encoded signal 129 generated by the image encoding device 100. For example, the encoded signal 221 is input to the image decoding apparatus 200 as a decoding target signal for each block. The image decoding apparatus 200 restores the decoded image 225 by performing variable length decoding, inverse quantization, and inverse transformation on the input decoding target signal.

An image decoding apparatus 200 illustrated in FIG. 7 includes an entropy decoding unit 201, an inverse quantization inverse transformation unit 202, an adder 203, a deblocking processing unit 204, a memory 205, an intra prediction unit 206, and a motion compensation unit. 207 and a changeover switch 208.

The entropy decoding unit 201 restores the quantization coefficient 222 by variable-length decoding the encoded signal 221 (encoded stream). Here, the encoded signal 221 (input stream) is a signal to be decoded and corresponds to data for each block of the encoded image data. In addition, the entropy decoding unit 201 acquires the motion data 227 from the encoded signal 221 and outputs the acquired motion data 227 to the motion compensation unit 207.

The inverse quantization inverse transform unit 202 restores the transform coefficient by inversely quantizing the quantized coefficient 222 restored by the entropy decoding unit 201. Then, the inverse quantization inverse transform unit 202 restores the residual signal 223 (also referred to as a prediction error or a difference signal) by inversely transforming the restored transform coefficient.

The adder 203 generates the decoded image 224 by adding the restored residual signal 223 and the prediction signal 226.

The deblocking processing unit 204 generates a decoded image 225 by performing a deblocking filter process on the generated decoded image 224. The decoded image 225 after the deblocking filter processing is output to the outside.

The memory 205 is a memory for storing a reference image used for motion compensation. Specifically, the memory 205 stores the decoded image 225 after the deblocking filter process is performed.

The intra prediction unit 206 generates a prediction signal (intra prediction signal) by performing intra prediction. Specifically, the intra prediction unit 206 performs intra prediction with reference to images around the block to be decoded (encoded signal 221) in the decoded image 224 generated by the adder 203, whereby the intra prediction signal Is generated.

The motion compensation unit 207 generates a prediction signal (inter prediction signal) by performing motion compensation based on the motion data 227 output from the entropy decoding unit 201.

The changeover switch 208 selects either the intra prediction signal or the inter prediction signal, and outputs the selected signal to the adder 203 as the prediction signal 226.

With the above configuration, the image decoding apparatus 200 according to the present embodiment decodes the decoded image 225 from the encoded signal 221 obtained by compressing and encoding the image.

Hereinafter, before describing the processing according to the present embodiment, the processing when decoding an encoded bitstream different from the intention as described above by a method that does not include the characteristic processing according to the present embodiment, This will be described with reference to FIG.

FIG. 8 is a flowchart showing an outline of a motion compensation process that does not include a characteristic process according to the present embodiment when a bitstream different from the intention assumed in the present embodiment is received.

First, the motion compensation unit 207 acquires a motion vector (motion data 227) from the encoded bit stream (encoded signal 221) (S201).

Next, the motion compensation unit 207 determines whether the reference destination of the motion vector includes outside the region (S202). Here, outside the area means outside the screen of the image signal (picture) or outside the MC restriction tile in the case of the MC restriction tile.

If it is determined that the reference destination of the motion vector includes outside the region (YES in S202), the motion compensation unit 207 determines whether the outside of the region is outside the screen (S203).

When it is outside the screen (YES in S203), the motion compensation unit 207 performs a process (padding process) of repeating pixels at the edge of the screen (S204). This padding process is performed, for example, in FIG. This is the same as the process shown in b). Next, the motion compensation unit 207 generates a motion compensated image with reference to the image after the padding process (S207).

On the other hand, when it is not outside the screen (when the target tile is an MC restricted tile and the reference destination of the motion vector is included in a different tile from the target tile) (NO in S203), the motion compensation unit 207 refers to outside the region. (S205). Since this process is an operation that is not defined in the normal decoding process, an error occurs and the decoding process stops. Alternatively, depending on the decoding device, an unexpected memory may be referred to and undefined data on the memory may be read as a reference image. As a result, the image decoding apparatus cannot continue the decoding operation or generates an image with very poor image quality by referring to indefinite data.

On the other hand, when the reference destination of the motion vector is not outside the area (NO in S202), the motion compensation unit 207 acquires the target area of the reference destination as usual (S206), and moves using the acquired image of the target area. A compensation image is generated (S207).

Note that Non-Patent Document 1 or the like does not specify how to decode the above-described bit stream.

As described above, when the above method is used, the image decoding device cannot decode the encoded bit stream, or the image quality of the decoded image is deteriorated.

On the other hand, as shown in the problem of the first embodiment, the boundary processing of the MC restriction tile is complicated, and there are cases where the image coding apparatus illegally processes the above-described complicated processing.

In the present embodiment, an image decoding method capable of suppressing deterioration in image quality without stopping the decoding process even in such a case will be described.

FIG. 9 is a flowchart showing an outline of processing in which the image decoding apparatus 200 according to the present embodiment determines the motion prediction mode.

First, similarly to step S201 shown in FIG. 8, the motion compensation unit 207 acquires a motion vector (motion data 227) from the encoded bit stream (encoded signal 221) (S301). Next, as in step S202, the motion compensation unit 207 determines whether the reference destination of the motion vector includes outside the region (S302).

If it is determined that the area outside the area is included (YES in S302), the motion compensation unit 207 determines whether the area outside the area is outside the screen (S303). When it is outside the screen (YES in S303), the motion compensation unit 207 performs padding processing (S304), and generates a motion compensated image with reference to the image after the padding processing (S307).

On the other hand, when it is not outside the screen (when the target tile is an MC restricted tile and the motion vector crosses the tile boundary) (NO in S303), the motion compensation unit 207 performs an out-of-region reference process (S305). The out-of-region reference processing is processing for complementing and generating out-of-region pixel values. Details of the processing for reference outside the area will be described later.

Also, the case where the motion vector crosses the tile boundary is a case where the reference destination of the motion vector is included in a tile different from the target tile, and a case where an integer pixel of another tile is referred to in calculation of the decimal pixel.

By defining this process, it is possible to prevent the image decoding apparatus from being stopped. In addition, when an out-of-region is referenced unintentionally on the encoding side, a mismatch (indicating that the image decoded locally on the encoding side is different from the decoded image) occurs, but for out-of-region reference By performing the above process, it is possible to improve the image quality (suppress image quality deterioration) compared to the case where an image stored at an indefinite memory address is used as a motion compensation image.

On the other hand, by performing similar motion compensation on the encoding side, the amount of boundary processing can be reduced by a method different from the method according to the first embodiment. Also, the image decoding apparatus 200 performs the same process, so that no mismatch occurs. Thereby, although it becomes a method different from the standard shown in nonpatent literature 1, the picture coding device and picture decoding device which can solve the above-mentioned subject by simple processing are realizable.

Next, the motion compensation unit 207 generates a motion compensated image using the image that has been subjected to the out-of-region reference processing (S307).

On the other hand, when the reference destination of the motion vector is not outside the region (NO in S302), the motion compensation unit 207 obtains the target region of the reference destination as usual (S306), as in step S206, and obtains the motion compensated image. Generate (S307).

Next, the aforementioned out-of-region reference processing will be described with reference to FIG. FIG. 10 is a diagram illustrating an example of special processing when a tile different from the target tile is referred to when the MC restricted tile is used. FIG. 10A is an example of processing in the case shown in FIG. 8, and the portion outside the target tile is not defined. Therefore, when the image decoding apparatus forcibly references this portion, the memory Indefinite values above may be used, and the decoding process may stop.

The process shown in FIG. 10B is the same as the process used in the case of the screen edge in step S304, and is also called a padding process. For example, as shown in FIG. 10, the target tile includes a pixel a, a pixel b, a pixel c, a pixel d, a pixel e, a pixel f, and a pixel g arranged in this order from the tile boundary. In this case, the motion compensation unit 207 fills the pixel value outside the target tile by repeating the pixel a adjacent to the tile boundary. By using this processing for the processing outside the area of the MC restricted tile, the circuit scale can be reduced because the circuit can be shared with the processing outside the screen.

Note that the motion compensation unit 207 may use a process different from the process outside the screen as the process outside the area of the MC restricted tile. For example, as illustrated in FIG. 10C, the motion compensation unit 207 folds the pixel a, the pixel b, the pixel c, the pixel d, the pixel e, the pixel f, and the pixel g in a mirror shape at the tile boundary. The pixel value outside the target tile is complemented by copying. In the padding process described above, there are cases where the same value suddenly continues, so that it is visually noticeable. On the other hand, since this method is a process that utilizes the continuity of video, visual image quality can be improved. For example, this method can improve the image quality compared to the padding process when the video gradually changes, such as a gradation image.

Alternatively, as shown in FIG. 10D, the motion compensation unit 207 may fill pixel values outside the target tile with a constant value X, as shown in FIG. Here, the case where the constant value X is the pixel value of the pixel a corresponds to (b) of FIG. Note that the motion compensation unit 207 may use, for example, the average value of the pixel values of the pixel a, the pixel b, the pixel c, and the pixel d close to the tile boundary as the constant value X. Further, the motion compensation unit 207 may select or calculate a value that reduces the change in pixel value at the tile boundary as the constant value X. In the case of this method, the processing amount is increased as compared with FIG. 10B, but deterioration in image quality can be suppressed.

By defining the out-of-region reference processing as described above, the image decoding apparatus 200 can perform the processing even if there is an unexpected reference in the bitstream that exceeds the boundary of the MC restricted tile. Thus, the decoding process can be performed without stopping the process and while suppressing the deterioration of the image quality.

Further, as illustrated in FIG. 11, the image decoding apparatus 200 indicates that an error has occurred when the motion compensation unit 207 determines that the motion vector reference destination includes outside the target tile (YES in S321). May be output (S322).

Thereby, since the image decoding apparatus 200 performs the decoding process while detecting the error, it is possible to grasp that the decoding result includes a mismatch when the error is detected. Thereby, the image decoding apparatus 200 does not need to detect an unnecessary mismatch, and can continuously perform reproduction. Further, the error detection result is transmitted to the provider of the encoded bitstream, so that the image encoding apparatus can be improved (for example, the mechanism as in Embodiment 1 is introduced).

As described above, the image decoding apparatus 200 according to the present embodiment decodes the encoded bitstream generated by the image encoding apparatus 100 according to Embodiment 1.

In addition, the image decoding apparatus 200 according to the present embodiment performs motion compensation on a target block included in a plurality of tiles using a prediction mode (merge mode or skip mode) that uses motion vectors of blocks around the target block. Do.

When the motion vector of the surrounding block refers to a reference block included in a tile different from the target tile including the target block, the image decoding apparatus 200 complements the pixel value of the reference block. Specifically, the image decoding apparatus 200 supplements the pixel value of the reference block using the pixel value included in the target block.

For example, as illustrated in FIG. 10B, the image decoding apparatus 200 copies pixel values of pixels included in the target block and closest to the reference block to a plurality of pixel values included in the reference block. Thus, the pixel value of the reference block is complemented.

Alternatively, as illustrated in FIG. 10C, when the target block and the reference block are adjacent to each other, the image decoding apparatus 200 folds back the pixel values of a plurality of pixels included in the target block with the adjacent boundary as an axis. Thus, the pixel value of the reference block is complemented by copying to a plurality of pixel values included in the reference block.

Alternatively, as illustrated in FIG. 10D, the image decoding apparatus 200 calculates an average value of a plurality of pixel values included in the target block, and uses the average value as a plurality of pixel values included in the reference block. Complement.

The image decoding apparatus 200 performs motion compensation using the complemented pixel values.

As described above, the image decoding apparatus 200 can execute the out-of-region reference process for the unintended encoded stream. That is, the image decoding apparatus 200 can avoid the decoding process from being stopped even in the case of the MC restricted tile. Thereby, stabilization of the image decoding apparatus 200 is realizable.

Also, by introducing this method to the image encoding device 100, the image encoding device 100 can be speeded up. That is, the motion compensation unit 109 included in the image coding apparatus 100 may perform the same processing as the motion compensation unit 207 according to the second embodiment. The image encoding apparatus 100 uses, as a reference image, an image generated by the above-described out-of-region reference process as a process when a motion vector refers to another tile. Thereby, the encoding process can be simplified and the circuit scale can be reduced. In this case, since the image decoding apparatus 200 includes the similar motion compensation unit 207, a system in which both circuit scales are reduced can be realized.

That is, the above process can be realized not only as an image decoding method in the image decoding apparatus 200 but also as an image encoding method in the image encoding apparatus 100. The above processing can also be realized as a motion compensation method in the image decoding apparatus 200 or the image encoding apparatus 100.

(Embodiment 3)
In the present embodiment, a structure of an encoded bit stream that can realize parallel processing will be described. In the present embodiment, the bitstream includes information that allows the image decoding apparatus 200 to easily realize parallel processing. Specifically, the bitstream includes information indicating where the mismatch occurs. That is, the bitstream includes information regarding a case where another tile is referred to in the motion prediction and motion compensation processing when the screen is divided into tiles and encoded.

FIG. 12 is a diagram showing a part of the syntax structure of a conventional MC restricted tile encoded bitstream. motion_constrained_tile_sets () is an information group indicating the area of the MC restricted tile. By referring to this information, the image decoding apparatus can know that the target stream does not make reference beyond the tile boundary. Further, this syntax structure includes an execute_sample_value_match_flag. The operation relating to this flag will be described with reference to FIG.

FIG. 13 is a flowchart of the operation relating to the execute_sample_value_match_flag. As illustrated in FIG. 13, when the exact_sample_value_match_flag is 0 (YES in S401), the image decoding apparatus determines that there is a mismatch (mismatch) in the stream (S402).

However, processing using this information has the following problems. There are the following three causes of mismatches in the MC restriction tile.

(1) When there is a process for filtering the tile boundary by a loop filter, in order to perform a filtering process using pixels outside the boundary even for MC restricted tiles, A difference (mismatch) occurs. (2) When a motion vector (including a skip / merge vector) refers to outside the tile boundary, a difference (mismatch) occurs between the locally decoded image and the decoded image at the time of encoding. (3) A difference (mismatch) occurs between the locally decoded image and the decoded image at the time of encoding by referring to the outside of the tile boundary for the generation of the decimal precision pixel.

In the above method, since these three cannot be distinguished, the image decoding apparatus 200 cannot identify what type of mismatch has occurred. Accordingly, there is a problem that it is difficult for the image decoding apparatus 200 to perform an appropriate decoding process according to the type of mismatch.

Hereinafter, the syntax structure of the encoded bitstream according to the present embodiment will be described. 14A to 14C are diagrams showing an example of the syntax structure of the encoded bitstream according to the present embodiment. 14A to 14C are diagrams illustrating syntax examples of motion_constrained_tile_sets included in the encoded bitstream according to the present embodiment. This information is called SEI and is handled as auxiliary information of the encoded bit stream.

In the example illustrated in FIG. 14A, the encoded bitstream includes a flag (filtering_mismatch_flag: 1) indicating that the above-described three mismatch causes are caused by a loop filter when the above-described exact_sample_value_match_flag is 0. A flag indicating that a mismatch occurs due to a filter) and a flag indicating that a mismatch occurs due to other than the loop filter (indicating that mismatch occurs due to other than the loop filter in the case of motion_constraint_mismatch_flag: 1). Thus, by providing the flags for distinguishing the cause of mismatch in a hierarchical manner, the amount of codes when mismatch does not occur can be reduced.

In the example illustrated in FIG. 14B, the encoded bitstream does not include the exact_sample_value_match_flag, but includes the inloop_filtering_mismatch_flag and the motion_constraint_missmatch_flag in parallel. The meaning of inloop_filtering_missmatch_flag is the same as filtering_missmatch_flag. This configuration has an advantage that the code amount is reduced when mismatched streams are frequently generated.

In the example illustrated in FIG. 14C, the motion_constraint_mismatch_flag further includes a flag (fractional_point_mismatch_flag) indicating that a mismatch occurs due to the generation processing of a fractional pixel, and a flag (skip_merge) indicating a mismatch (skip_merge) indicating a mismatch due to skip and merge processing. Has been.

Note that the configuration shown here is an example, and the configurations shown in FIGS. 14A to 14C may be combined.

In this way, the image decoding device 200 can appropriately decode the encoded bitstream by notifying the image decoding device 200 of the possibility of a fine mismatch.

FIG. 15 is a flowchart showing a processing flow of the image decoding apparatus 200 in the case shown in FIG. 14A. As illustrated in FIG. 15, the image decoding apparatus 200 determines that a problem occurs when the execute_sample_value_match_flag is 0 (YES in S421) (S422).

Furthermore, when the motion_constraint_mismatch_flag is 1 (YES in S423), the image decoding apparatus 200 determines that the special processing for out-of-region reference is used (S424), and otherwise (NO in S423), it is a mismatch regarding the loop filter. It is determined that there is an out-of-region reference process for the loop filter (S425). For example, the image decoding apparatus 200 uses the mirroring process shown in FIG. 10C for the loop filter, and uses the padding process shown in FIG. 10B for out-of-region reference for motion compensation. As described above, the image decoding apparatus 200 switches the decoding process according to these filters.

In this example, the image coding apparatus 100 uses a flag as information indicating the cause of the mismatch, but may use information indicating a number instead of the flag. For example, when this number is 0, it indicates that there is no mismatch (no special processing), when the number is 1, indicates padding processing, when the number is 2, indicates mirroring processing, and when the number is 3, the average value In the case where the number is 4 or more, the value -4 is used as a fixed value for the reference image. With such a configuration, an encoded stream that can be processed in parallel using a simple MC restriction tile can be realized without degrading the image quality of the decoded image.

Note that such processing may be defined as shown in FIG. Conventionally, since processing when a mismatch occurs is indefinite, the image decoding apparatus has been processed as an error or referred to indefinite data. Therefore, by specifying special processing as shown in the figure, it is possible to generate a decoded image with little deterioration.

When there is a boundary filter and there is a mismatch, the image decoding apparatus 200 may avoid the mismatch by using the value before the filter as a reference image and passing the filter process later. By using the bit stream configuration according to the present embodiment, the image decoding apparatus 200 can specify when a mismatch occurs in the filter processing, and thus can perform the above-described processing.

Further, depending on the image decoding apparatus, a process of reading out only the pixels having a specified mismatch possibility from the memory may be performed. Here, when the cause of the mismatch cannot be identified, the mismatch cannot be appropriately avoided. On the other hand, as in the present embodiment, when the information specifying the mismatch is included in the encoded bitstream, the image decoding apparatus 200 reads or writes only the pixel data related to the specified mismatch from the memory. Processing can be performed. For example, if the mismatch is caused by the boundary filter process, the image decoding apparatus 200 writes or reads only pixel data necessary for the boundary filter process into the memory. For example, in the case of a mismatch due to the skip / merge process, the image decoding apparatus 200 writes or reads data of pixels in a range that can be taken by the skip / merge process to the shared memory. Even in the case of special pixel generation processing, as shown in FIG. 2A, the image decoding apparatus 200 may read data of three pixels of adjacent tiles.

As described above, the information indicating what is the mismatch is included in the bitstream, so that the image decoding apparatus 200 can avoid the mismatch when there is a margin in processing. Further, the image decoding apparatus 200 can easily determine how to generate a decoded image even when the pixel data cannot be read from the memory. The image quality can be improved.

As described above, the image coding apparatus 100 according to the present embodiment generates information for specifying that the motion vector of the surrounding block refers to a reference block included in a tile different from the target tile. Then, an encoded bit stream including the information is generated. In other words, the image encoding device 100 generates two or more flags or two or more information indicating that the encoded bitstream includes an event of violation of the standard, and a code including the two or more flags or the two or more information. Generate a generalized bitstream.

Thereby, the image encoding device 100 can generate an encoded bitstream that can be simply decoded by the image decoding device or can generate a decoded image with little deterioration.

Although the image encoding device and the image decoding device according to the embodiment have been described above, the present invention is not limited to this embodiment.

In addition, each processing unit included in the image encoding device and the image decoding device according to the above embodiment is typically realized as an LSI that is an integrated circuit. These may be individually made into one chip, or may be made into one chip so as to include a part or all of them.

Further, the integration of circuits is not limited to LSI, and may be realized by a dedicated circuit or a general-purpose processor. An FPGA (Field Programmable Gate Array) that can be programmed after manufacturing the LSI or a reconfigurable processor that can reconfigure the connection and setting of circuit cells inside the LSI may be used.

In each of the above embodiments, each component may be configured by dedicated hardware or may be realized by executing a software program suitable for each component. Each component may be realized by a program execution unit such as a CPU or a processor reading and executing a software program recorded on a recording medium such as a hard disk or a semiconductor memory.

In other words, the image encoding device and the image decoding device include a control circuit (control circuit) and a storage device (storage) electrically connected to the control circuit (accessible from the control circuit). The control circuit includes at least one of dedicated hardware and a program execution unit. Further, when the control circuit includes a program execution unit, the storage device stores a software program executed by the program execution unit.

Furthermore, the present invention may be the software program or a non-transitory computer-readable recording medium on which the program is recorded. Needless to say, the program can be distributed via a transmission medium such as the Internet.

Further, all the numbers used above are illustrated for specifically explaining the present invention, and the present invention is not limited to the illustrated numbers.

In addition, division of functional blocks in the block diagram is an example, and a plurality of functional blocks can be realized as one functional block, a single functional block can be divided into a plurality of functions, or some functions can be transferred to other functional blocks. May be. In addition, functions of a plurality of functional blocks having similar functions may be processed in parallel or time-division by a single hardware or software.

In addition, the order in which the steps included in the image encoding method or the image decoding method are executed is for illustrating the present invention specifically, and may be in an order other than the above. . Also, some of the above steps may be executed simultaneously (in parallel) with other steps.

As described above, the image encoding device and the image decoding device according to one or more aspects of the present invention have been described based on the embodiment, but the present invention is not limited to this embodiment. Unless it deviates from the gist of the present invention, the embodiment in which various modifications conceived by those skilled in the art have been made in the present embodiment, and forms constructed by combining components in different embodiments are also applicable to one or more of the present invention. It may be included within the scope of the embodiments.

(Embodiment 4)
By recording a program for realizing the configuration of the moving image encoding method (image encoding method) or the moving image decoding method (image decoding method) shown in each of the above embodiments on a storage medium, each of the above embodiments It is possible to easily execute the processing shown in the form in the independent computer system. The storage medium may be any medium that can record a program, such as a magnetic disk, an optical disk, a magneto-optical disk, an IC card, and a semiconductor memory.

Furthermore, application examples of the moving picture coding method (picture coding method) and the moving picture decoding method (picture decoding method) shown in the above embodiments and a system using the same will be described. The system has an image encoding / decoding device including an image encoding device using an image encoding method and an image decoding device using an image decoding method. Other configurations in the system can be appropriately changed according to circumstances.

FIG. 17 is a diagram showing an overall configuration of a content supply system ex100 that realizes a content distribution service. A communication service providing area is divided into desired sizes, and base stations ex106, ex107, ex108, ex109, and ex110, which are fixed wireless stations, are installed in each cell.

The content supply system ex100 includes a computer ex111, a PDA (Personal Digital Assistant) ex112, a camera ex113, a mobile phone ex114, a game machine ex115 via the Internet ex101, the Internet service provider ex102, the telephone network ex104, and the base stations ex106 to ex110. Etc. are connected.

However, the content supply system ex100 is not limited to the configuration shown in FIG. 17, and may be connected by combining any one of the elements. In addition, each device may be directly connected to the telephone network ex104 without going from the base station ex106, which is a fixed wireless station, to ex110. In addition, the devices may be directly connected to each other via short-range wireless or the like.

The camera ex113 is a device that can shoot moving images such as a digital video camera, and the camera ex116 is a device that can shoot still images and movies such as a digital camera. The mobile phone ex114 is a GSM (registered trademark) (Global System for Mobile Communications) system, a CDMA (Code Division Multiple Access) system, a W-CDMA (Wideband-Code Division Multiple Access) system, or an LTE (Long Terminal Term Evolution). It is possible to use any of the above-mentioned systems, HSPA (High Speed Packet Access) mobile phone, PHS (Personal Handyphone System), or the like.

In the content supply system ex100, the camera ex113 and the like are connected to the streaming server ex103 through the base station ex109 and the telephone network ex104, thereby enabling live distribution and the like. In live distribution, content that is shot by a user using the camera ex113 (for example, music live video) is encoded as described in each of the above embodiments (that is, in one aspect of the present invention). Functions as an image encoding device), and transmits it to the streaming server ex103. On the other hand, the streaming server ex103 stream-distributes the content data transmitted to the requested client. Examples of the client include a computer ex111, a PDA ex112, a camera ex113, a mobile phone ex114, and a game machine ex115 that can decode the encoded data. Each device that receives the distributed data decodes the received data and reproduces it (that is, functions as an image decoding device according to one embodiment of the present invention).

Note that the captured data may be encoded by the camera ex113, the streaming server ex103 that performs data transmission processing, or may be shared with each other. Similarly, the decryption processing of the distributed data may be performed by the client, the streaming server ex103, or may be performed in common with each other. In addition to the camera ex113, still images and / or moving image data captured by the camera ex116 may be transmitted to the streaming server ex103 via the computer ex111. The encoding process in this case may be performed by any of the camera ex116, the computer ex111, and the streaming server ex103, or may be performed in a shared manner.

Further, these encoding / decoding processes are generally performed in the computer ex111 and the LSI ex500 included in each device. The LSI ex500 may be configured as a single chip or a plurality of chips. It should be noted that moving image encoding / decoding software is incorporated into some recording medium (CD-ROM, flexible disk, hard disk, etc.) that can be read by the computer ex111, etc., and encoding / decoding processing is performed using the software. May be. Furthermore, when the mobile phone ex114 is equipped with a camera, moving image data acquired by the camera may be transmitted. The moving image data at this time is data encoded by the LSI ex500 included in the mobile phone ex114.

Further, the streaming server ex103 may be a plurality of servers or a plurality of computers, and may process, record, and distribute data in a distributed manner.

As described above, in the content supply system ex100, the encoded data can be received and reproduced by the client. Thus, in the content supply system ex100, the information transmitted by the user can be received, decrypted and reproduced by the client in real time, and personal broadcasting can be realized even for a user who does not have special rights or facilities.

In addition to the example of the content supply system ex100, as shown in FIG. 18, the digital broadcast system ex200 also includes at least the video encoding device (video encoding device) or video decoding of each of the above embodiments. Any of the devices (image decoding devices) can be incorporated. Specifically, in the broadcast station ex201, multiplexed data obtained by multiplexing music data and the like on video data is transmitted to a communication or satellite ex202 via radio waves. This video data is data encoded by the moving image encoding method described in each of the above embodiments (that is, data encoded by the image encoding apparatus according to one aspect of the present invention). Receiving this, the broadcasting satellite ex202 transmits a radio wave for broadcasting, and this radio wave is received by a home antenna ex204 capable of receiving satellite broadcasting. The received multiplexed data is decoded and reproduced by an apparatus such as the television (receiver) ex300 or the set top box (STB) ex217 (that is, functions as an image decoding apparatus according to one embodiment of the present invention).

Also, a reader / recorder ex218 that reads and decodes multiplexed data recorded on a recording medium ex215 such as a DVD or a BD, or encodes a video signal on the recording medium ex215 and, in some cases, multiplexes and writes it with a music signal. It is possible to mount the moving picture decoding apparatus or moving picture encoding apparatus described in the above embodiments. In this case, the reproduced video signal is displayed on the monitor ex219, and the video signal can be reproduced in another device or system using the recording medium ex215 on which the multiplexed data is recorded. Alternatively, a moving picture decoding apparatus may be mounted in a set-top box ex217 connected to a cable ex203 for cable television or an antenna ex204 for satellite / terrestrial broadcasting and displayed on the monitor ex219 of the television. At this time, the moving picture decoding apparatus may be incorporated in the television instead of the set top box.

FIG. 19 is a diagram illustrating a television (receiver) ex300 that uses the video decoding method and the video encoding method described in each of the above embodiments. The television ex300 obtains or outputs multiplexed data in which audio data is multiplexed with video data via the antenna ex204 or the cable ex203 that receives the broadcast, and demodulates the received multiplexed data. Alternatively, the modulation / demodulation unit ex302 that modulates multiplexed data to be transmitted to the outside, and the demodulated multiplexed data is separated into video data and audio data, or the video data and audio data encoded by the signal processing unit ex306 Is provided with a multiplexing / demultiplexing unit ex303.

The television ex300 also decodes the audio data and the video data, or encodes the information, the audio signal processing unit ex304, the video signal processing unit ex305 (the image encoding device or the image according to one embodiment of the present invention) A signal processing unit ex306 that functions as a decoding device), a speaker ex307 that outputs the decoded audio signal, and an output unit ex309 that includes a display unit ex308 such as a display that displays the decoded video signal. Furthermore, the television ex300 includes an interface unit ex317 including an operation input unit ex312 that receives an input of a user operation. Furthermore, the television ex300 includes a control unit ex310 that performs overall control of each unit, and a power supply circuit unit ex311 that supplies power to each unit. In addition to the operation input unit ex312, the interface unit ex317 includes a bridge unit ex313 connected to an external device such as a reader / recorder ex218, a recording unit ex216 such as an SD card, and an external recording unit such as a hard disk. A driver ex315 for connecting to a medium, a modem ex316 for connecting to a telephone network, and the like may be included. Note that the recording medium ex216 is capable of electrically recording information by using a nonvolatile / volatile semiconductor memory element to be stored. Each part of the television ex300 is connected to each other via a synchronous bus.

First, a configuration in which the television ex300 decodes and reproduces multiplexed data acquired from the outside by the antenna ex204 and the like will be described. The television ex300 receives a user operation from the remote controller ex220 or the like, and demultiplexes the multiplexed data demodulated by the modulation / demodulation unit ex302 by the multiplexing / demultiplexing unit ex303 based on the control of the control unit ex310 having a CPU or the like. Furthermore, in the television ex300, the separated audio data is decoded by the audio signal processing unit ex304, and the separated video data is decoded by the video signal processing unit ex305 using the decoding method described in each of the above embodiments. The decoded audio signal and video signal are output from the output unit ex309 to the outside. At the time of output, these signals may be temporarily stored in the buffers ex318, ex319, etc. so that the audio signal and the video signal are reproduced in synchronization. Also, the television ex300 may read multiplexed data from recording media ex215 and ex216 such as a magnetic / optical disk and an SD card, not from broadcasting. Next, a configuration in which the television ex300 encodes an audio signal or a video signal and transmits the signal to the outside or to a recording medium will be described. The television ex300 receives a user operation from the remote controller ex220 and the like, encodes an audio signal with the audio signal processing unit ex304, and converts the video signal with the video signal processing unit ex305 based on the control of the control unit ex310. Encoding is performed using the encoding method described in (1). The encoded audio signal and video signal are multiplexed by the multiplexing / demultiplexing unit ex303 and output to the outside. When multiplexing, these signals may be temporarily stored in the buffers ex320, ex321, etc. so that the audio signal and the video signal are synchronized. Note that a plurality of buffers ex318, ex319, ex320, and ex321 may be provided as illustrated, or one or more buffers may be shared. Further, in addition to the illustrated example, data may be stored in the buffer as a buffer material that prevents system overflow and underflow, for example, between the modulation / demodulation unit ex302 and the multiplexing / demultiplexing unit ex303.

In addition to acquiring audio data and video data from broadcasts, recording media, and the like, the television ex300 has a configuration for receiving AV input of a microphone and a camera, and performs encoding processing on the data acquired from them. Also good. Here, the television ex300 has been described as a configuration capable of the above-described encoding processing, multiplexing, and external output, but these processing cannot be performed, and only the above-described reception, decoding processing, and external output are possible. It may be a configuration.

In addition, when reading or writing multiplexed data from a recording medium by the reader / recorder ex218, the decoding process or the encoding process may be performed by either the television ex300 or the reader / recorder ex218, The reader / recorder ex218 may share with each other.

As an example, FIG. 20 shows a configuration of the information reproducing / recording unit ex400 when data is read from or written to an optical disk. The information reproducing / recording unit ex400 includes elements ex401, ex402, ex403, ex404, ex405, ex406, and ex407 described below. The optical head ex401 irradiates a laser spot on the recording surface of the recording medium ex215 that is an optical disk to write information, and detects information reflected from the recording surface of the recording medium ex215 to read the information. The modulation recording unit ex402 electrically drives a semiconductor laser built in the optical head ex401 and modulates the laser beam according to the recording data. The reproduction demodulator ex403 amplifies the reproduction signal obtained by electrically detecting the reflected light from the recording surface by the photodetector built in the optical head ex401, separates and demodulates the signal component recorded on the recording medium ex215, and is necessary To play back information. The buffer ex404 temporarily holds information to be recorded on the recording medium ex215 and information reproduced from the recording medium ex215. The disk motor ex405 rotates the recording medium ex215. The servo control unit ex406 moves the optical head ex401 to a predetermined information track while controlling the rotational drive of the disk motor ex405, and performs a laser spot tracking process. The system control unit ex407 controls the entire information reproduction / recording unit ex400. In the reading and writing processes described above, the system control unit ex407 uses various types of information held in the buffer ex404, and generates and adds new information as necessary. The modulation recording unit ex402, the reproduction demodulation unit This is realized by recording / reproducing information through the optical head ex401 while operating the ex403 and the servo control unit ex406 in a coordinated manner. The system control unit ex407 includes, for example, a microprocessor, and executes these processes by executing a read / write program.

In the above, the optical head ex401 has been described as irradiating a laser spot. However, a configuration in which higher-density recording is performed using near-field light may be used.

FIG. 21 shows a schematic diagram of a recording medium ex215 that is an optical disk. Guide grooves (grooves) are formed in a spiral shape on the recording surface of the recording medium ex215, and address information indicating the absolute position on the disc is recorded in advance on the information track ex230 by changing the shape of the groove. This address information includes information for specifying the position of the recording block ex231 that is a unit for recording data, and the recording block is specified by reproducing the information track ex230 and reading the address information in a recording or reproducing apparatus. Can do. Further, the recording medium ex215 includes a data recording area ex233, an inner peripheral area ex232, and an outer peripheral area ex234. The area used for recording user data is the data recording area ex233, and the inner circumference area ex232 and the outer circumference area ex234 arranged on the inner or outer circumference of the data recording area ex233 are used for specific purposes other than user data recording. Used. The information reproducing / recording unit ex400 reads / writes encoded audio data, video data, or multiplexed data obtained by multiplexing these data with respect to the data recording area ex233 of the recording medium ex215.

In the above description, an optical disk such as a single-layer DVD or BD has been described as an example. However, the present invention is not limited to these, and an optical disk having a multilayer structure and capable of recording other than the surface may be used. Also, an optical disc with a multi-dimensional recording / reproducing structure, such as recording information using light of different wavelengths in the same place on the disc, or recording different layers of information from various angles. It may be.

Further, in the digital broadcasting system ex200, the car ex210 having the antenna ex205 can receive data from the satellite ex202 and the like, and the moving image can be reproduced on a display device such as the car navigation ex211 that the car ex210 has. The configuration of the car navigation ex211 may be, for example, a configuration in which a GPS receiving unit is added in the configuration illustrated in FIG. 19, and the same may be considered for the computer ex111, the mobile phone ex114, and the like.

FIG. 22A is a diagram showing the mobile phone ex114 using the moving picture decoding method and the moving picture encoding method described in the above embodiment. The mobile phone ex114 includes an antenna ex350 for transmitting and receiving radio waves to and from the base station ex110, a camera unit ex365 capable of capturing video and still images, a video captured by the camera unit ex365, a video received by the antenna ex350, and the like Is provided with a display unit ex358 such as a liquid crystal display for displaying the decrypted data. The mobile phone ex114 further includes a main body unit having an operation key unit ex366, an audio output unit ex357 such as a speaker for outputting audio, an audio input unit ex356 such as a microphone for inputting audio, a captured video, In the memory unit ex367 for storing encoded data or decoded data such as still images, recorded audio, received video, still images, mails, or the like, or an interface unit with a recording medium for storing data A slot ex364 is provided.

Furthermore, a configuration example of the mobile phone ex114 will be described with reference to FIG. 22B. The mobile phone ex114 has a power supply circuit part ex361, an operation input control part ex362, and a video signal processing part ex355 with respect to a main control part ex360 that comprehensively controls each part of the main body including the display part ex358 and the operation key part ex366. , A camera interface unit ex363, an LCD (Liquid Crystal Display) control unit ex359, a modulation / demodulation unit ex352, a multiplexing / demultiplexing unit ex353, an audio signal processing unit ex354, a slot unit ex364, and a memory unit ex367 are connected to each other via a bus ex370. ing.

When the end of call and the power key are turned on by a user operation, the power supply circuit unit ex361 starts up the mobile phone ex114 in an operable state by supplying power from the battery pack to each unit.

The cellular phone ex114 converts the audio signal collected by the audio input unit ex356 in the voice call mode into a digital audio signal by the audio signal processing unit ex354 based on the control of the main control unit ex360 having a CPU, a ROM, a RAM, and the like. Then, this is subjected to spectrum spread processing by the modulation / demodulation unit ex352, digital-analog conversion processing and frequency conversion processing are performed by the transmission / reception unit ex351, and then transmitted via the antenna ex350. The mobile phone ex114 also amplifies the received data received via the antenna ex350 in the voice call mode, performs frequency conversion processing and analog-digital conversion processing, performs spectrum despreading processing by the modulation / demodulation unit ex352, and performs voice signal processing unit After being converted into an analog audio signal by ex354, this is output from the audio output unit ex357.

Further, when an e-mail is transmitted in the data communication mode, the text data of the e-mail input by operating the operation key unit ex366 of the main unit is sent to the main control unit ex360 via the operation input control unit ex362. The main control unit ex360 performs spread spectrum processing on the text data in the modulation / demodulation unit ex352, performs digital analog conversion processing and frequency conversion processing in the transmission / reception unit ex351, and then transmits the text data to the base station ex110 via the antenna ex350. . In the case of receiving an e-mail, almost the reverse process is performed on the received data and output to the display unit ex358.

When transmitting video, still images, or video and audio in the data communication mode, the video signal processing unit ex355 compresses the video signal supplied from the camera unit ex365 by the moving image encoding method described in the above embodiments. Encode (that is, function as an image encoding device according to an aspect of the present invention), and send the encoded video data to the multiplexing / demultiplexing unit ex353. The audio signal processing unit ex354 encodes the audio signal picked up by the audio input unit ex356 while the camera unit ex365 images a video, a still image, etc., and sends the encoded audio data to the multiplexing / separating unit ex353. To do.

The multiplexing / demultiplexing unit ex353 multiplexes the encoded video data supplied from the video signal processing unit ex355 and the encoded audio data supplied from the audio signal processing unit ex354 by a predetermined method, and is obtained as a result. The multiplexed data is subjected to spread spectrum processing by the modulation / demodulation unit (modulation / demodulation circuit unit) ex352, digital-analog conversion processing and frequency conversion processing by the transmission / reception unit ex351, and then transmitted via the antenna ex350.

Decode multiplexed data received via antenna ex350 when receiving video file data linked to a homepage, etc. in data communication mode, or when receiving e-mail with video and / or audio attached Therefore, the multiplexing / separating unit ex353 separates the multiplexed data into a video data bit stream and an audio data bit stream, and performs video signal processing on the video data encoded via the synchronization bus ex370. The encoded audio data is supplied to the audio signal processing unit ex354 while being supplied to the unit ex355. The video signal processing unit ex355 decodes the video signal by decoding using the video decoding method corresponding to the video encoding method described in each of the above embodiments (that is, an image according to an aspect of the present invention). For example, video and still images included in the moving image file linked to the home page are displayed from the display unit ex358 via the LCD control unit ex359. The audio signal processing unit ex354 decodes the audio signal, and the audio is output from the audio output unit ex357.

In addition to the transmission / reception type terminal having both the encoder and the decoder, the terminal such as the mobile phone ex114 is referred to as a transmission terminal having only an encoder and a receiving terminal having only a decoder. There are three possible mounting formats. Furthermore, in the digital broadcasting system ex200, it has been described that multiplexed data in which music data or the like is multiplexed with video data is received and transmitted, but data in which character data or the like related to video is multiplexed in addition to audio data It may be video data itself instead of multiplexed data.

As described above, the moving picture encoding method or the moving picture decoding method shown in each of the above embodiments can be used in any of the above-described devices / systems. The described effect can be obtained.

Further, the present invention is not limited to the above-described embodiment, and various changes and modifications can be made without departing from the scope of the present invention.

(Embodiment 5)
The moving picture coding method or apparatus shown in the above embodiments and the moving picture coding method or apparatus compliant with different standards such as MPEG-2, MPEG4-AVC, and VC-1 are appropriately switched as necessary. Thus, it is also possible to generate video data.

Here, when a plurality of pieces of video data conforming to different standards are generated, it is necessary to select a decoding method corresponding to each standard when decoding. However, since it is impossible to identify which standard the video data to be decoded complies with, there arises a problem that an appropriate decoding method cannot be selected.

In order to solve this problem, multiplexed data obtained by multiplexing audio data or the like with video data is configured to include identification information indicating which standard the video data conforms to. A specific configuration of multiplexed data including video data generated by the moving picture encoding method or apparatus shown in the above embodiments will be described below. The multiplexed data is a digital stream in the MPEG-2 transport stream format.

FIG. 23 is a diagram showing a structure of multiplexed data. As shown in FIG. 23, multiplexed data is obtained by multiplexing one or more of a video stream, an audio stream, a presentation graphics stream (PG), and an interactive graphics stream. The video stream indicates the main video and sub-video of the movie, the audio stream (IG) indicates the main audio portion of the movie and the sub-audio mixed with the main audio, and the presentation graphics stream indicates the subtitles of the movie. Here, the main video indicates a normal video displayed on the screen, and the sub-video is a video displayed on a small screen in the main video. The interactive graphics stream indicates an interactive screen created by arranging GUI components on the screen. The video stream is encoded by the moving image encoding method or apparatus shown in the above embodiments, or the moving image encoding method or apparatus conforming to the conventional standards such as MPEG-2, MPEG4-AVC, and VC-1. ing. The audio stream is encoded by a method such as Dolby AC-3, Dolby Digital Plus, MLP, DTS, DTS-HD, or linear PCM.

Each stream included in the multiplexed data is identified by PID. For example, 0x1011 for video streams used for movie images, 0x1100 to 0x111F for audio streams, 0x1200 to 0x121F for presentation graphics, 0x1400 to 0x141F for interactive graphics streams, 0x1B00 to 0x1B1F are assigned to video streams used for sub-pictures, and 0x1A00 to 0x1A1F are assigned to audio streams used for sub-audio mixed with the main audio.

FIG. 24 is a diagram schematically showing how multiplexed data is multiplexed. First, a video stream ex235 composed of a plurality of video frames and an audio stream ex238 composed of a plurality of audio frames are converted into PES packet sequences ex236 and ex239, respectively, and converted into TS packets ex237 and ex240. Similarly, the data of the presentation graphics stream ex241 and interactive graphics ex244 are converted into PES packet sequences ex242 and ex245, respectively, and further converted into TS packets ex243 and ex246. The multiplexed data ex247 is configured by multiplexing these TS packets into one stream.

FIG. 25 shows in more detail how the video stream is stored in the PES packet sequence. The first row in FIG. 25 shows a video frame sequence of the video stream. The second level shows a PES packet sequence. As indicated by arrows yy1, yy2, yy3, and yy4 in FIG. 25, a plurality of Video Presentation Units in the video stream are divided for each picture and stored in the payload of the PES packet. . Each PES packet has a PES header, and a PTS (Presentation Time-Stamp) that is a display time of a picture and a DTS (Decoding Time-Stamp) that is a decoding time of a picture are stored in the PES header.

FIG. 26 shows the format of the TS packet that is finally written in the multiplexed data. The TS packet is a 188-byte fixed-length packet composed of a 4-byte TS header having information such as a PID for identifying a stream and a 184-byte TS payload for storing data. The PES packet is divided and stored in the TS payload. The In the case of a BD-ROM, a 4-byte TP_Extra_Header is added to a TS packet, forms a 192-byte source packet, and is written in multiplexed data. In TP_Extra_Header, information such as ATS (Arrival_Time_Stamp) is described. ATS indicates the transfer start time of the TS packet to the PID filter of the decoder. Source packets are arranged in the multiplexed data as shown in the lower part of FIG. 26, and the number incremented from the head of the multiplexed data is called SPN (source packet number).

In addition, TS packets included in the multiplexed data include PAT (Program Association Table), PMT (Program Map Table), PCR (Program Clock Reference), and the like in addition to each stream such as video / audio / caption. PAT indicates what the PID of the PMT used in the multiplexed data is, and the PID of the PAT itself is registered as 0. The PMT has the PID of each stream such as video / audio / subtitles included in the multiplexed data and the attribute information of the stream corresponding to each PID, and has various descriptors related to the multiplexed data. The descriptor includes copy control information for instructing permission / non-permission of copying of multiplexed data. In order to synchronize the ATC (Arrival Time Clock), which is the ATS time axis, and the STC (System Time Clock), which is the PTS / DTS time axis, the PCR corresponds to the ATS in which the PCR packet is transferred to the decoder. Contains STC time information.

FIG. 27 is a diagram for explaining the data structure of the PMT in detail. A PMT header describing the length of data included in the PMT is arranged at the head of the PMT. After that, a plurality of descriptors related to multiplexed data are arranged. The copy control information and the like are described as descriptors. After the descriptor, a plurality of pieces of stream information regarding each stream included in the multiplexed data are arranged. The stream information includes a stream descriptor in which a stream type, a stream PID, and stream attribute information (frame rate, aspect ratio, etc.) are described to identify a compression codec of the stream. There are as many stream descriptors as the number of streams existing in the multiplexed data.

When recording on a recording medium or the like, the multiplexed data is recorded together with the multiplexed data information file.

As shown in FIG. 28, the multiplexed data information file is management information of multiplexed data, has a one-to-one correspondence with the multiplexed data, and includes multiplexed data information, stream attribute information, and an entry map.

The multiplexed data information includes a system rate, a reproduction start time, and a reproduction end time as shown in FIG. The system rate indicates a maximum transfer rate of multiplexed data to a PID filter of a system target decoder described later. The ATS interval included in the multiplexed data is set to be equal to or less than the system rate. The playback start time is the PTS of the first video frame of the multiplexed data, and the playback end time is set by adding the playback interval for one frame to the PTS of the video frame at the end of the multiplexed data.

In the stream attribute information, as shown in FIG. 29, attribute information about each stream included in the multiplexed data is registered for each PID. The attribute information has different information for each video stream, audio stream, presentation graphics stream, and interactive graphics stream. The video stream attribute information includes the compression codec used to compress the video stream, the resolution of the individual picture data constituting the video stream, the aspect ratio, and the frame rate. It has information such as how much it is. The audio stream attribute information includes the compression codec used to compress the audio stream, the number of channels included in the audio stream, the language supported, and the sampling frequency. With information. These pieces of information are used for initialization of the decoder before the player reproduces it.

In this embodiment, among the multiplexed data, the stream type included in the PMT is used. Also, when multiplexed data is recorded on the recording medium, video stream attribute information included in the multiplexed data information is used. Specifically, in the video encoding method or apparatus shown in each of the above embodiments, the video encoding shown in each of the above embodiments for the stream type or video stream attribute information included in the PMT. There is provided a step or means for setting unique information indicating that the video data is generated by the method or apparatus. With this configuration, it is possible to discriminate between video data generated by the moving picture encoding method or apparatus described in the above embodiments and video data compliant with other standards.

FIG. 30 shows steps of the moving picture decoding method according to the present embodiment. In step exS100, the stream type included in the PMT or the video stream attribute information included in the multiplexed data information is acquired from the multiplexed data. Next, in step exS101, it is determined whether or not the stream type or the video stream attribute information indicates multiplexed data generated by the moving picture encoding method or apparatus described in the above embodiments. To do. When it is determined that the stream type or the video stream attribute information is generated by the moving image encoding method or apparatus described in the above embodiments, in step exS102, the above embodiments are performed. Decoding is performed by the moving picture decoding method shown in the form. If the stream type or video stream attribute information indicates that it conforms to a standard such as conventional MPEG-2, MPEG4-AVC, or VC-1, in step exS103, the conventional information Decoding is performed by a moving image decoding method compliant with the standard.

In this way, by setting a new unique value in the stream type or video stream attribute information, whether or not decoding is possible with the moving picture decoding method or apparatus described in each of the above embodiments is performed. Judgment can be made. Therefore, even when multiplexed data conforming to different standards is input, an appropriate decoding method or apparatus can be selected, and therefore decoding can be performed without causing an error. In addition, the moving picture encoding method or apparatus or the moving picture decoding method or apparatus described in this embodiment can be used in any of the above-described devices and systems.

(Embodiment 6)
The moving picture encoding method and apparatus and moving picture decoding method and apparatus described in the above embodiments are typically realized by an LSI that is an integrated circuit. As an example, FIG. 31 shows a configuration of an LSI ex500 that is made into one chip. The LSI ex500 includes elements ex501, ex502, ex503, ex504, ex505, ex506, ex507, ex508, and ex509 described below, and each element is connected via a bus ex510. The power supply circuit unit ex505 is activated to an operable state by supplying power to each unit when the power supply is on.

For example, when performing the encoding process, the LSI ex500 performs the microphone ex117 and the camera ex113 by the AV I / O ex509 based on the control of the control unit ex501 including the CPU ex502, the memory controller ex503, the stream controller ex504, the drive frequency control unit ex512, and the like. The AV signal is input from the above. The input AV signal is temporarily stored in an external memory ex511 such as SDRAM. Based on the control of the control unit ex501, the accumulated data is divided into a plurality of times as appropriate according to the processing amount and the processing speed and sent to the signal processing unit ex507, and the signal processing unit ex507 encodes an audio signal and / or video. Signal encoding is performed. Here, the encoding process of the video signal is the encoding process described in the above embodiments. The signal processing unit ex507 further performs processing such as multiplexing the encoded audio data and the encoded video data according to circumstances, and outputs the result from the stream I / Oex 506 to the outside. The output multiplexed data is transmitted to the base station ex107 or written to the recording medium ex215. It should be noted that data should be temporarily stored in the buffer ex508 so as to be synchronized when multiplexing.

In the above description, the memory ex511 is described as an external configuration of the LSI ex500. However, a configuration included in the LSI ex500 may be used. The number of buffers ex508 is not limited to one, and a plurality of buffers may be provided. The LSI ex500 may be made into one chip or a plurality of chips.

In the above description, the control unit ex501 includes the CPU ex502, the memory controller ex503, the stream controller ex504, the drive frequency control unit ex512, and the like, but the configuration of the control unit ex501 is not limited to this configuration. For example, the signal processing unit ex507 may further include a CPU. By providing a CPU also in the signal processing unit ex507, the processing speed can be further improved. As another example, the CPU ex502 may be configured to include a signal processing unit ex507 or, for example, an audio signal processing unit that is a part of the signal processing unit ex507. In such a case, the control unit ex501 is configured to include a signal processing unit ex507 or a CPU ex502 having a part thereof.

In addition, although it was set as LSI here, it may be called IC, system LSI, super LSI, and ultra LSI depending on the degree of integration.

Further, the method of circuit integration is not limited to LSI, and implementation with a dedicated circuit or a general-purpose processor is also possible. An FPGA (Field Programmable Gate Array) that can be programmed after manufacturing the LSI or a reconfigurable processor that can reconfigure the connection and setting of circuit cells inside the LSI may be used. Such a programmable logic device typically loads or reads a program constituting software or firmware from a memory or the like, so that the moving image encoding method or the moving image described in each of the above embodiments is used. An image decoding method can be performed.

Furthermore, if integrated circuit technology that replaces LSI emerges as a result of advances in semiconductor technology or other derived technology, it is naturally also possible to integrate functional blocks using this technology. Biotechnology can be applied.

(Embodiment 7)
When decoding the video data generated by the moving picture encoding method or apparatus shown in the above embodiments, the video data conforming to the conventional standards such as MPEG-2, MPEG4-AVC, and VC-1 is decoded. It is conceivable that the amount of processing increases compared to the case. Therefore, in LSI ex500, it is necessary to set a driving frequency higher than the driving frequency of CPU ex502 when decoding video data compliant with the conventional standard. However, when the drive frequency is increased, there is a problem that power consumption increases.

In order to solve this problem, moving picture decoding devices such as the television ex300 and LSI ex500 are configured to identify which standard the video data conforms to and switch the driving frequency in accordance with the standard. FIG. 32 shows a configuration ex800 in the present embodiment. The drive frequency switching unit ex803 sets the drive frequency high when the video data is generated by the moving image encoding method or apparatus described in the above embodiments. Then, the decoding processing unit ex801 that executes the moving picture decoding method described in each of the above embodiments is instructed to decode the video data. On the other hand, when the video data is video data compliant with the conventional standard, compared to the case where the video data is generated by the moving picture encoding method or apparatus shown in the above embodiments, Set the drive frequency low. Then, it instructs the decoding processing unit ex802 compliant with the conventional standard to decode the video data.

More specifically, the drive frequency switching unit ex803 includes the CPU ex502 and the drive frequency control unit ex512 in FIG. Also, the decoding processing unit ex801 that executes the moving picture decoding method shown in each of the above embodiments and the decoding processing unit ex802 that complies with the conventional standard correspond to the signal processing unit ex507 in FIG. The CPU ex502 identifies which standard the video data conforms to. Then, based on the signal from the CPU ex502, the drive frequency control unit ex512 sets the drive frequency. Further, based on the signal from the CPU ex502, the signal processing unit ex507 decodes the video data. Here, for identification of video data, for example, the identification information described in the fifth embodiment may be used. The identification information is not limited to that described in the fifth embodiment, and any information that can identify which standard the video data conforms to may be used. For example, it is possible to identify which standard the video data conforms to based on an external signal that identifies whether the video data is used for a television or a disk. In some cases, identification may be performed based on such an external signal. In addition, the selection of the driving frequency in the CPU ex502 may be performed based on, for example, a lookup table in which video data standards and driving frequencies are associated with each other as shown in FIG. The look-up table is stored in the buffer ex508 or the internal memory of the LSI, and the CPU ex502 can select the drive frequency by referring to the look-up table.

FIG. 33 shows steps for executing the method of the present embodiment. First, in step exS200, the signal processing unit ex507 acquires identification information from the multiplexed data. Next, in step exS201, the CPU ex502 identifies whether the video data is generated by the encoding method or apparatus described in each of the above embodiments based on the identification information. When the video data is generated by the encoding method or apparatus shown in the above embodiments, in step exS202, the CPU ex502 sends a signal for setting the drive frequency high to the drive frequency control unit ex512. Then, the drive frequency control unit ex512 sets a high drive frequency. On the other hand, if it indicates that the video data conforms to the conventional standards such as MPEG-2, MPEG4-AVC, and VC-1, in step exS203, the CPU ex502 drives the signal for setting the drive frequency low. This is sent to the frequency control unit ex512. Then, in the drive frequency control unit ex512, the drive frequency is set to be lower than that in the case where the video data is generated by the encoding method or apparatus described in the above embodiments.

Furthermore, the power saving effect can be further enhanced by changing the voltage applied to the LSI ex500 or the device including the LSI ex500 in conjunction with the switching of the driving frequency. For example, when the drive frequency is set low, it is conceivable that the voltage applied to the LSI ex500 or the device including the LSI ex500 is set low as compared with the case where the drive frequency is set high.

In addition, the setting method of the driving frequency may be set to a high driving frequency when the processing amount at the time of decoding is large, and to a low driving frequency when the processing amount at the time of decoding is small. It is not limited to the method. For example, the amount of processing for decoding video data compliant with the MPEG4-AVC standard is larger than the amount of processing for decoding video data generated by the moving picture encoding method or apparatus described in the above embodiments. It is conceivable that the setting of the driving frequency is reversed to that in the case described above.

Furthermore, the method for setting the drive frequency is not limited to the configuration in which the drive frequency is lowered. For example, when the identification information indicates that the video data is generated by the moving image encoding method or apparatus described in the above embodiments, the voltage applied to the LSIex500 or the apparatus including the LSIex500 is set high. However, when it is shown that the video data conforms to the conventional standards such as MPEG-2, MPEG4-AVC, VC-1, etc., it is also possible to set the voltage applied to the LSIex500 or the device including the LSIex500 low. It is done. As another example, when the identification information indicates that the video data is generated by the moving image encoding method or apparatus described in the above embodiments, the driving of the CPU ex502 is stopped. If the video data conforms to the standards such as MPEG-2, MPEG4-AVC, VC-1, etc., the CPU ex502 is temporarily stopped because there is room in processing. Is also possible. Even when the identification information indicates that the video data is generated by the moving image encoding method or apparatus described in each of the above embodiments, if there is a margin for processing, the CPU ex502 is temporarily driven. It can also be stopped. In this case, it is conceivable to set the stop time shorter than in the case where the video data conforms to the conventional standards such as MPEG-2, MPEG4-AVC, and VC-1.

Thus, it is possible to save power by switching the drive frequency according to the standard to which the video data conforms. In addition, when the battery is used to drive the LSI ex500 or the device including the LSI ex500, it is possible to extend the life of the battery with power saving.

(Embodiment 8)
A plurality of video data that conforms to different standards may be input to the above-described devices and systems such as a television and a mobile phone. As described above, the signal processing unit ex507 of the LSI ex500 needs to support a plurality of standards in order to be able to decode even when a plurality of video data complying with different standards is input. However, when the signal processing unit ex507 corresponding to each standard is used individually, there is a problem that the circuit scale of the LSI ex500 increases and the cost increases.

In order to solve this problem, a decoding processing unit for executing the moving picture decoding method shown in each of the above embodiments and a decoding conforming to a standard such as MPEG-2, MPEG4-AVC, or VC-1 The processing unit is partly shared. An example of this configuration is shown as ex900 in FIG. 35A. For example, the moving picture decoding method shown in each of the above embodiments and the moving picture decoding method compliant with the MPEG4-AVC standard are processed in processes such as entropy coding, inverse quantization, deblocking filter, and motion compensation. Some contents are common. For common processing contents, the decoding processing unit ex902 corresponding to the MPEG4-AVC standard is shared, and for other processing contents specific to one aspect of the present invention that do not correspond to the MPEG4-AVC standard, a dedicated decoding processing unit A configuration using ex901 is conceivable. In particular, since one aspect of the present invention has a feature in motion compensation, for example, a dedicated decoding processing unit ex901 is used for motion compensation, and other dequantization, entropy decoding, deblocking filter, and the like are used. For any or all of these processes, it is conceivable to share the decoding processing unit. Regarding the sharing of the decoding processing unit, regarding the common processing content, the decoding processing unit for executing the moving picture decoding method described in each of the above embodiments is shared, and the processing content specific to the MPEG4-AVC standard As for, a configuration using a dedicated decoding processing unit may be used.

Further, ex1000 in FIG. 35B shows another example in which processing is partially shared. In this example, a dedicated decoding processing unit ex1001 corresponding to the processing content specific to one aspect of the present invention, a dedicated decoding processing unit ex1002 corresponding to the processing content specific to another conventional standard, and one aspect of the present invention And a common decoding processing unit ex1003 corresponding to the processing contents common to the moving image decoding method according to the above and other conventional moving image decoding methods. Here, the dedicated decoding processing units ex1001 and ex1002 are not necessarily specialized in one aspect of the present invention or processing content specific to other conventional standards, and can execute other general-purpose processing. Also good. Also, the configuration of the present embodiment can be implemented by LSI ex500.

As described above, the processing content common to the moving picture decoding method according to one aspect of the present invention and the moving picture decoding method of the conventional standard reduces the circuit scale of the LSI by sharing the decoding processing unit, In addition, the cost can be reduced.

The present invention can be applied to an image encoding method, an image decoding method, an image encoding device, and an image decoding device. Further, the present invention can be used for various purposes such as data storage, transmission or communication. For example, the present invention can be used for information display devices and imaging devices such as televisions, digital video recorders, car navigation systems, cellular phones, digital still cameras, and digital video cameras.

DESCRIPTION OF SYMBOLS 100 Image coding apparatus 101 Subtractor 102 Transform quantization part 103 Entropy encoding part 104,202 Inverse quantization inverse transformation part 105,203 Adder 106,204 Deblocking process part 107,205 Memory 108,206

Intra prediction part

109 , 207 Motion compensation unit 110

Motion detection unit

112, 208 Changeover switch 121

Input image

122, 124, 223

Residual signal

123, 222

Quantization coefficient

125, 126 Local decoded

image

127, 226

Predicted signal

128, 227

Motion data

129, 221 Coded signal 200 Image decoding device 201

Entropy decoding unit

224, 225 Decoded image

Claims

A motion compensation method for performing motion compensation on a target block included in a plurality of tiles using a prediction mode using a motion vector of a block around the target block,
When the motion vector of the surrounding block refers to a reference block included in a tile different from the target tile including the target block, a complementing step of complementing the pixel value of the reference block;
And a motion compensation step of performing the motion compensation using the complemented pixel values.
The motion compensation method according to claim 1, wherein in the complementing step, the pixel value of the reference block is complemented using a pixel value included in the target block.
In the complementing step, the pixel value of the reference block is complemented by copying pixel values of the pixel included in the target block and closest to the reference block to a plurality of pixel values included in the reference block. The motion compensation method according to claim 2.
In the complementing step, when the target block and the reference block are adjacent to each other, the pixel values of the plurality of pixels included in the target block are folded around the adjacent boundary as an axis, and the plurality of pixels included in the reference block The motion compensation method according to claim 2, wherein the pixel value of the reference block is complemented by copying to a value.
The motion compensation method according to claim 2, wherein in the complementing step, an average value of a plurality of pixel values included in the target block is calculated, and the average value is supplemented as a plurality of pixel values included in the reference block.
An image encoding method using the motion compensation method according to any one of claims 1 to 5,
Generating information for specifying that the motion vector of the surrounding block refers to the reference block included in the tile different from the target tile;
An image encoding method for generating an encoded bitstream including the information.
A dividing step of dividing the image into a plurality of tiles;
Encoding a target block included in the plurality of tiles using any one of a plurality of prediction modes including a prediction mode using a motion vector of a block around the target block,
In the encoding step,
An image encoding method for encoding the target block without using a motion vector that refers to a block included in a tile different from the target tile including the target block.
In the encoding step,
Determining whether the motion vector of the surrounding block refers to a block included in the tile different from the target tile;
When it is determined that the motion vector of the surrounding block refers to the block included in the tile different from the target tile, the motion block other than the motion vector of the surrounding block is encoded using the motion vector. The image encoding method according to claim 7.
In the encoding step,
Determine whether the target block is located within a certain value from the tile boundary,
When it is determined that the target block is located within the predetermined value from the tile boundary, the target block is used using a prediction mode other than the skip mode and the merge mode, which is a mode in which the motion vectors of the surrounding blocks are used as they are. The image encoding method according to claim 7.
An image decoding method for decoding an encoded bitstream generated by the image encoding method according to any one of claims 7 to 9.
A processing circuit;
A storage device accessible from the processing circuit,
The processing circuit uses the storage device,
An image encoding apparatus for executing the motion compensation method according to claim 1.
A processing circuit;
A storage device accessible from the processing circuit,
The processing circuit uses the storage device,
An image decoding apparatus that executes the motion compensation method according to claim 1.
A processing circuit;
A storage device accessible from the processing circuit,
The processing circuit uses the storage device,
An image encoding apparatus that executes the image encoding method according to claim 7.
A processing circuit;
A storage device accessible from the processing circuit,
The processing circuit uses the storage device,
An image decoding apparatus that executes the image decoding method according to claim 10.