WO2013153808A1 - Image decoding method and image decoding device - Google Patents

Abstract

In the present invention, an image decoding method which decodes an image that has been subject to scalable decoding includes steps for: acquiring an NAL unit type and a layer identifier included in a header of an NAL unit; identifying a layer of an image on the basis of the layer identifier; and, if the NAL unit type is an NAL unit type for a depth map indicating depth information for an image, decoding the image by decoding the depth map included in the NAL unit as a depth map related to the layer.

Description

Image decoding method and image decoding apparatus

The present invention relates to a method for decoding scalable video encoding and multiview video encoded images.

The multi-view video coding (MVC) standard and the scalable video coding (SVC: Scalable Video Coding) standard are specified as extensions of the ISO / IEC 14496-10 Advanced Video Coding (AVC) standard. For example, refer nonpatent literature 1).

In this specification, multi-view video coding and scalable video coding are collectively referred to as scalable coding. That is, the scalable coding includes at least one of multi-view video coding and scalable video coding.

However, in the prior art, it is desired to more efficiently decode a scalable encoded image.

Therefore, the present invention provides an image decoding method capable of efficiently decoding a scalable encoded image.

An image decoding method according to an aspect of the present invention is an image decoding method for decoding a scalable encoded image, the step of acquiring a NAL unit type and a layer identifier included in a header of a NAL unit, and the layer identifier Identifying the layer of the image, and when the NAL unit type is a NAL unit type of a depth map indicating depth information of the image, decoding the depth map included in the NAL unit as a depth map related to the layer, thereby Decoding the image.

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

The image decoding method according to an aspect of the present invention can efficiently decode a scalable encoded image.

FIG. 1 is a diagram showing a configuration of a NAL unit in the HEVC standard. FIG. 2 is a diagram illustrating a layer structure of encoding target data in scalable video encoding and multi-view video encoding. FIG. 3 is a diagram illustrating an example of a depth map corresponding to a layer. FIG. 4A is a diagram illustrating an example of specific values inserted into the NAL header. FIG. 4B is a diagram illustrating an example of upper syntax including bind information. FIG. 5 is a diagram illustrating a specific example of the bind information. FIG. 6A is a diagram illustrating a modification of specific values inserted into the NAL header. FIG. 6B is a diagram illustrating a modification of the upper syntax including the binding information. FIG. 7 is a diagram illustrating another example of the depth map corresponding to the layer. FIG. 8 is a diagram illustrating a specific example of the bind information. FIG. 9 is an overall configuration diagram of a content supply system that implements a content distribution service. FIG. 10 is an overall configuration diagram of a digital broadcasting system. FIG. 11 is a block diagram illustrating a configuration example of a television. FIG. 12 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. 13 is a diagram illustrating a structure example of a recording medium that is an optical disk. FIG. 14A is a diagram illustrating an example of a mobile phone. FIG. 14B is a block diagram illustrating a configuration example of a mobile phone. FIG. 15 is a diagram showing a structure of multiplexed data. FIG. 16 is a diagram schematically showing how each stream is multiplexed in the multiplexed data. FIG. 17 is a diagram showing in more detail how the video stream is stored in the PES packet sequence. FIG. 18 is a diagram showing the structure of TS packets and source packets in multiplexed data. FIG. 19 is a diagram illustrating a data structure of the PMT. FIG. 20 is a diagram illustrating an internal configuration of multiplexed data information. FIG. 21 shows the internal structure of stream attribute information. FIG. 22 is a diagram illustrating steps for identifying video data. FIG. 23 is a block diagram illustrating a configuration example of an integrated circuit that implements the moving picture coding method and the moving picture decoding method according to each embodiment. FIG. 24 is a diagram illustrating a configuration for switching the driving frequency. FIG. 25 is a diagram illustrating steps for identifying video data and switching between driving frequencies. FIG. 26 is a diagram illustrating an example of a look-up table in which video data standards are associated with drive frequencies. FIG. 27A is a diagram illustrating an example of a configuration for sharing a module of a signal processing unit. FIG. 27B is a diagram illustrating another example of a configuration for sharing a module of a signal processing unit.

(Summary of Invention)
An image decoding method according to an aspect of the present invention is an image decoding method for decoding a scalable encoded image, the step of acquiring a NAL unit type and a layer identifier included in a header of a NAL unit, and the layer identifier Identifying the layer of the image, and if the NAL unit type is a NAL unit type of a depth map indicating depth information of the image, decoding the depth map included in the NAL unit as a depth map for the layer, Decoding the image.

According to this, by acquiring the NAL unit type included in the header of the NAL unit, it can be easily known that the depth map is included in the NAL unit. In addition, by acquiring the layer identifier included in the header of the NAL unit, it is possible to easily identify the layer to which the depth map included in the NAL unit is. Therefore, it is possible to efficiently decode a scalable encoded image.

For example, the layer may be specified by acquiring the scalable type identifier of the layer from binding information for binding the layer identifier and the scalable type identifier of the layer.

For example, the scalable type identifier includes a spatial identifier that identifies a spatial layer in spatial scalable video coding, a view identifier that identifies a view in multi-view video coding, and a quality identifier that identifies a quality layer in quality scalable video coding And at least one of them.

For example, the scalable coding may include at least one of the spatial scalable video coding, the multi-view video coding, and the quality scalable video coding.

For example, the bind information may be included in a syntax higher than the sequence parameter set.

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

Hereinafter, embodiments will be specifically described with reference to the drawings.

It should be noted that each of the embodiments described below shows a comprehensive or specific example. Numerical values, shapes, materials, components, arrangement positions and connection forms of components, steps, order of steps, and the like shown in the following embodiments are merely examples, and are not intended to limit the scope of the claims. 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)
FIG. 1 shows a configuration of a network abstraction layer unit (NAL unit) in the HEVC (High Efficiency Video Coding) standard. The NAL unit includes a NAL header, an RBSP (Raw Byte Sequence Payload), and an RBSP trailing bit. The NAL header has a fixed length of 2 bytes (16 bits) and includes a NAL unit type (Nal_unit_type (6 bits)) indicating the type of the NAL unit. In the NAL header, Reserved_one_5 bits (5 bits) is reserved for future expansion.

FIG. 2 shows a layer structure of data to be encoded in scalable video coding (SVC) and multi-view video coding (MVC). The SVC includes a space SVC. In the example of FIG. 2, the encoding target data has three layers in the spatial direction, and a spatial identifier (dependency_id (0 to 2)) is assigned to each spatial layer. This spatial identifier is information for identifying a spatial hierarchy in spatial scalable video coding.

Further, in the example of FIG. 2, the encoding target data has four views (views), and a view identifier (view_id (0 to 3)) is assigned to each view. This view identifier is information for identifying a view in multi-view video coding.

Note that SVC includes quality SVC. Although not shown in FIG. 2, a quality identifier (quality_id) is assigned to each quality layer. This quality identifier is information for identifying a quality layer in quality scalable video coding.

As described above, each layer (rectangle in the figure) in scalable coding (scalable video coding (SVC) and multi-view video coding (MVC)) can be identified using dependency_id, view_id, and quality_id. .

However, here, in order to make it easier to specify the layer, a layer identifier (layer_id) is assigned to each layer. In FIG. 2, layer_id (0 to 11) is assigned to each layer. By using layer_id in this way, the decoder can immediately identify the layer.

FIG. 3 shows a depth map (DepthMap) corresponding to the layer in addition to the layer structure of data to be encoded in the scalable video coding (SVC) and multi-view video coding (MVC) shown in FIG. . A hatched rectangle indicates a layer, and a white rectangle indicates DepthMap corresponding to the layer. The layer is a normal texture image and is a video coding layer (VCL).

DepthMap is a map showing the depth information of a normal image. For example, when photographing using a camera, DepthMap indicates how far the object shown in the photographed image is from the position of the camera. The range of depth information is wide. For example, a subject that is only 3 meters away and a background that is 100 meters away are also conceivable. Accordingly, scaling is appropriately performed in order to express DepthMap with a predetermined bit (for example, 8 bits).

There are various methods for creating DepthMap. For example, distance data can be acquired using a range finder. In computer graphics (CG), since a CG image originally has 3D information, it is easy to create DepthMap.

FIG. 3 shows a configuration in which DepthMap corresponding to all space layers and view layers (textures) exists. Also, DepthMap can be specified by assigning the same layer_id to the DepthMap as the layer corresponding to the DepthMap.

In the example of FIG. 3, DepthMap corresponding to all layers exists, but the present invention is not limited to this. For example, the DepthMap can be configured to exist only in the base layer (dependency_id = 0).

FIG. 4A shows an example of specific values inserted in the NAL header shown in FIG. In the case of a NAL unit including a layer subjected to scalable video coding (SVC) and multi-view video coding (MVC) in a payload (RBSP), the NAL unit type of VCL is inserted in Nal_unit_type. Then, layer_id corresponding to the layer is inserted into Reserved_one_5 bits.

That is, when the payload of the NAL unit includes a layer subjected to scalable video coding and multi-view video coding, a value indicating VLC is set in Nal_unit_type, and layer_id corresponding to the layer is set in Reserved_one_5bits. Is set.

Also, in the case of a NAL unit including DepthMap in the payload, the NAL unit type of DepthMap (a value indicating DepthMap) is inserted into Nal_unit_type. As a result, the decoder can know that the DepthMap is included in the payload only by referring to the NAL unit type. Then, layer_id of the layer corresponding to the DepthMap is inserted into Reserved_one_5 bits of the NAL header of DepthMap.

That is, when DepthMap is included in the payload of the NAL unit, a value indicating DepthMap is set in Nal_unit_type, and a layer_id of a layer corresponding to the DepthMap is set in Reserved_one_5bits.

FIG. 4B shows an example of upper syntax including bind information. That is, FIG. 4B shows an example of binding information for binding layer_id to dependency_id, view_id, and quality_id using the upper syntax. For example, in the sequence parameter set (SPS), both are bound. When the decoder acquires layer_id of the NAL header, the decoder can know the scalable type identifier (dependency_id, view_id, quality_id), which is specific information of the layer, by referring to the binding information of the SPS.

Note that layer_id does not necessarily have to be bound to all values of dependency_id, view_id, and quality_id. That is, the scalable type identifier bound to the layer identifier may include at least one of a spatial identifier (dependency_id), a view identifier (view_id), and a quality identifier (quality_id). For example, if only SVC is performed and MVC is not performed, layer_id need not be bound to view_id.

Note that FIG. 4B shows only a part of the SPS extracted. The SPS includes layer_id bindings by the number of layer_ids (the number of layers).

Further, in FIG. 4B, the layer_id of the layer and the layer_id (DepthMap) of the DepthMap are further bound. Thereby, the decoder can specify DepthMap corresponding to the layer specified by layer_id. As shown in the example of FIG. 3, when DepthMap corresponding to all layers exists, layer_id (DepthMap) has the same value as layer_id. Note that layer_id does not necessarily have to be bound to layer_id (DepthMap). For example, when there is no DepthMap corresponding to a layer, there is no need for layer_id (DepthMap) bound to layer_id.

Further, when the layer and the DepthMap corresponding to the layer use the same layer_id as shown in FIG. 4A, it is not necessary to bind explicitly in FIG. 4B. The SPS only needs to include a flag indicating whether or not the layer has DepthMap. When the flag is true, the layer and the DepthMap corresponding to the layer are bound.

FIG. 5 uses a higher level syntax to bind layer_id to dependency_id, view_id, and quality_id, and to layer_id and layerMap layer_id (denoted as layer_id (DepthMap) for ease of explanation). A specific example of the case is shown.

SPS is used as the upper syntax, but it is not limited to this. You may bind in a layer higher or lower than SPS.

FIG. 5 shows an example of the layer structure shown in FIG. 3 and the corresponding DepthMap binding. In the first binding, layer_id = 0, dependency_id = 0, view_id = 0, and quality_id = 0 are bound. Also, layer_id = 0 and depthMap layer_id (DepthMap) = 0 are bound.

In the second binding, layer_id = 1, dependency_id = 1, view_id = 0, and quality_id = 0 are bound. Also, layer_id = 1 and depthMap layer_id (DepthMap) = 1 are bound.

The SPS includes such a binding (the number of layers (12)).

As described above, when the NAL unit type is the NAL unit type of the depth map, by decoding the depth map included in the NAL unit as the depth map related to the layer specified from the layer identifier, the scalable encoded image can be obtained. It can be efficiently decoded.

(Modification)
FIG. 6A is a modification of FIG. 4A. In FIG. 4A, when Nal_unit_type is a NAL unit type of DepthMap, layer_id of the layer corresponding to the DepthMap is inserted into Reserved_one_5 bits. On the other hand, in FIG. 6A, depthmap_id for specifying DepthMap is defined separately from layer_id of the layer corresponding to DepthMap, and depthmap_id of the DepthMap is inserted (set) in Reserved_one_5 bits of the NAL header. By separating DepthMap from layer_id (not specified using layer_id), binding with a higher degree of freedom becomes possible.

FIG. 6B is obtained by modifying FIG. 4A as shown in FIG. In FIG. 6B, what is bound to layer_id is depthmap_id. Thereby, the decoder can specify DepthMap corresponding to the layer specified by layer_id using depthmap_id. Note that layer_id does not necessarily need to be bound to depthmap_id. For example, when there is no DepthMap corresponding to the layer, there is no need for depthmap_id bound to layer_id.

FIG. 7 shows another example of the layer structure of data to be encoded in the scalable video coding (SVC) and multi-view video coding (MVC) shown in FIG. 3 and the DepthMap corresponding to that layer.

In FIG. 3, depth maps corresponding to all layers exist, but in FIG. 7, depth maps exist only in some layers. In each view, there is one or two DepthMaps.

Also, in FIG. 7, DepthMap is specified by depthmap_id described in FIGS. 6A and 6B. Depthmap_id (12 to 16) is assigned to each DepthMap.

DepthMap is less affected by the difference in resolution, and one (common) DepthMap can be used for each view. For example, when there is a DepthMap corresponding only to the base layer as in the 0th view (view_id = 0), the depth map (depthmap_id = 12) is used by scaling the depth map in a spatial upper layer having a large resolution. Is possible. That is, since there is no corresponding DepthMap in the layer of layer_id = 1, the DepthMap (depthmap_id = 12) corresponding to the layer of layer_id = 0 is referred to. Here, which depth map is referred to becomes a problem, which will be described later with reference to FIG.

FIG. 8 shows a specific example of the upper syntax including the binding information. That is, FIG. 8 shows a specific example when the layer_id and the depthmap_id are bound using the upper syntax. SPS is used as the upper syntax, but it is not limited to this. You may bind layer_id and depthmap_id in a layer higher or lower than SPS.

FIG. 8 shows an example of the layer structure shown in FIG. 7 and the corresponding DepthMap binding. In FIG. 8, description of dependency_id, view_id, and quality_id is omitted.

In the first binding, layer_id = 0 and depthmap_id = 12 are bound. In the second binding, layer_id = 1 and depthmap_id = 12 are bound. As described with reference to FIG. 7, there is no corresponding DepthMap in the layer with layer_id = 1. By referring to the binding indicated by SPS, it is understood that the layer with layer_id = 1 should refer to DepthMap (depthmap_id = 12) corresponding to the layer with layer_id = 0. Similarly, it can be seen that the layer of layer_id = 2 should refer to DepthMap (depthmap_id = 12) corresponding to the layer of layer_id = 0.

In the fourth view (view_id = 3), there are multiple DepthMaps in the View. Even in this case, by referring to the binding between layer_id and depthmap_id, it is possible to specify the DepthMap that the layer should refer to. For example, it can be seen that the layer of layer_id = 10 should refer to DepthMap (depthmap_id = 15) corresponding to the layer of layer_id = 9.

As described above, the decoder can easily specify the DepthMap that the layer refers to by binding the layer_id that identifies the layer and the depthmap_id that identifies the DepthMap using the upper syntax.

The image decoding method according to one or more aspects of the present invention has 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, one or more of the present invention may be applied to the present embodiment in which various modifications conceived by those skilled in the art have been made in this embodiment, or a combination of components in different embodiments. It may be included within the scope of the embodiments.

In the above embodiment, 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 decoding apparatus may include a control circuit and a storage device (storage) electrically connected to the control circuit (accessible from the control circuit). The control circuit may include at least one of dedicated hardware and a program execution unit. In addition, when the control circuit includes a program execution unit, the storage device may store a software program executed by the program execution unit.

The software that realizes the image decoding method of the above-described embodiment is the following program. That is, this program is an image decoding method for decoding a scalable encoded image to a control circuit (computer), the NAL unit type and the layer identifier included in the header of the NAL unit being acquired, and the layer identifier Identifying the layer of the image from, and if the NAL unit type is a depth map NAL unit type indicating depth information of the image, decoding the depth map included in the NAL unit as a depth map for the layer, And a step of decoding the image.

(Embodiment 2)
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. 9 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.

This 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. 9, and may be connected by combining any 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.

Also, 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. 10, the digital broadcast system ex200 also includes at least the moving image encoding device (image encoding device) or the moving image decoding according to 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. 11 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. 12 shows a configuration of the information reproducing / recording unit ex400 when data is read from or written to the 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. 13 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.

Also, 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. Note that the configuration of the car navigation ex211 may be, for example, a configuration in which a GPS receiving unit is added to the configuration illustrated in FIG.

FIG. 14A 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. 14B. 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 3)
The moving picture coding method or apparatus shown in each of 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. 15 is a diagram showing a structure of multiplexed data. As shown in FIG. 15, the 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 the video stream used for the sub-picture, and 0x1A00 to 0x1A1F are assigned to the audio stream used for the sub-audio mixed with the main audio.

FIG. 16 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. 17 shows in more detail how the video stream is stored in the PES packet sequence. The first row in FIG. 17 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. 17, a plurality of Video Presentation Units in the video stream are divided into pictures, B pictures, and P pictures 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. 18 shows the format of TS packets that are 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. 18, 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 where the PCR packet is transferred to the decoder. Contains STC time information.

FIG. 19 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. 20, 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.

As shown in FIG. 20, the multiplexed data information includes a system rate, a reproduction start time, and a reproduction end time. 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. 21, the attribute information for 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. 22 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 4)
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. 23 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 uses the AV I / O ex509 to perform the microphone ex117 and the camera ex113 based on the control of the control unit ex501 including the CPU ex502, the memory controller ex503, the stream controller ex504, the driving 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 5)
When decoding video data generated by the moving picture encoding method or apparatus described in each of 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. 24 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 described in each of the above embodiments and the decoding processing unit ex802 that conforms to 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 the identification of the video data, for example, it is conceivable to use the identification information described in the third embodiment. The identification information is not limited to that described in Embodiment 3, 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. 25 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 6)
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. 27A. 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. 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. 27B 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 image decoding apparatus according to an aspect of the present invention can be used for, for example, a television receiver, a digital video recorder, a car navigation, a mobile phone, a digital camera, a digital video camera, or the like.

Claims (6)

1. An image decoding method for decoding a scalable encoded image, comprising:
   Obtaining a NAL unit type and a layer identifier included in the header of the NAL unit;
   Identifying a layer of the image from the layer identifier;
   And decoding the image by decoding the depth map included in the NAL unit as a depth map for the layer when the NAL unit type is a depth map NAL unit type indicating depth information of the image. Decryption method.
2. The image decoding method according to claim 1, wherein the layer is specified by acquiring the scalable type identifier of the layer from binding information for binding the layer identifier and the scalable type identifier of the layer.
3. The scalable type identifier includes: a spatial identifier that identifies a spatial layer in spatial scalable video coding; a view identifier that identifies a view in multi-view video coding; and a quality identifier that identifies a quality layer in quality scalable video coding. The image decoding method according to claim 2, comprising at least one of them.
4. The image decoding method according to claim 3, wherein the scalable coding includes at least one of the spatial scalable video coding, the multi-view video coding, and the quality scalable video coding.
5. The image decoding method according to any one of claims 2 to 4, wherein the binding information is included in a syntax higher than a sequence parameter set.
6. An image decoding apparatus comprising a control circuit and a storage device electrically connected to the control circuit,
   The image decoding apparatus that executes the image decoding method according to claim 1.

Images