JP2001069503A - Video signal coder and coding method therefor, and video signal decoder and decoding method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the time required for decoding processing by generating a bit stream, where a desired image frame can easily be accessed even the case of reverse access so as to easily access the desired image frame at reverse access time to each image frame in the generated stream. SOLUTION: This video signal coder is provided with a compression coding section 11 for an image frame, corresponding to coded data that compresses, encodes a video signal in the unit of image frames, and provides address information denoting the position of the image frame in a bit stream to the unit of image frames and encodes the result, an address information storage section 15 that stores compression-coded image frames, and one-frame delay section 14, that delay coded data of the address information stored in the storage section 15 by one image frame. The compression coding section adds coded data of information of one preceding address to compression-coded data of each image frame in the bit stream from the one-frame delay section.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video signal encoding apparatus and method for compressing and encoding a video signal and outputting the compressed and encoded data as a bit stream, and a compression encoded bit. The present invention relates to a video signal decoding device for decoding a stream into a video signal and a decoding method thereof.

[0002]

2. Description of the Related Art As a moving image compression encoding method, MP
EG (Moving Picture Experts Group) standards and H.264. 26
International standards such as three standards are known. As is well known, these compression encoding methods include intra-frame compression encoding for performing complete compression encoding within one image frame, and image frames other than those to be compression-encoded (hereinafter, also referred to as “reference images”). And inter-frame compression encoding, which performs compression encoding using correlation information with. Accordingly, in these compression coding methods, the compression algorithm, that is, the above-described intra-frame compression coding and inter-frame compression coding is appropriately selected in accordance with the characteristics of the original image to greatly reduce the data amount. It was possible.

[0003] However, in the above-described compression coding method, the data compression rate can be improved by performing inter-frame compression coding, but the decoding of the compressed and coded data requires decoding of the reference image. Data and correlation information were required. More specifically, when decoding processing is performed on an image frame that has been compression-encoded by inter-frame compression encoding, first, data of a reference image (intra-frame compression-encoded image) referred to is decoded. It is necessary to decode a target image frame using the decoded reference image and correlation information. Further, since the above-mentioned compression coding method is a variable-length coding method in which the amount of data after coding differs for each image frame, the data access position (reading position) exemplified at the start position of the image frame is changed. Processing for identification was required. As a conventional video signal encoding device for reducing the processing at the time of decoding, there is, for example, a moving image encoding device disclosed in Japanese Patent Application Laid-Open No. 7-50838. This conventional video signal encoding device counts the encoded data amount for each image frame, and inserts a code indicating the counted data amount into a bit stream. This allows
In this conventional video signal encoding device, an attempt has been made to reduce the process of specifying the reading position during the decoding process.

Hereinafter, the conventional video signal encoding apparatus will be specifically described with reference to FIG. FIG. 5 is a block diagram showing a configuration of a conventional video signal encoding device.
As shown in FIG. 5, this conventional video signal encoding device includes:
Encoding unit 4 that performs encoding processing on external video data
1. Code buffer 4 sequentially connected to the encoding unit 41
2 and an insertion unit 43, and a code data amount counting unit 44 connected between the encoding unit 41 and the insertion unit 43. The encoding unit 41 performs a predetermined encoding process on the input video data, and outputs the encoded video data to the code buffer 42 as encoded data. The code buffer unit 42 includes the encoding unit 4
1 is temporarily stored and output to the insertion unit 43. The code data amount counting unit 44 counts the data amount of the encoded data generated by the encoding unit 41 (hereinafter, referred to as “code data amount”), and outputs a code indicating the code data amount to the insertion unit 43. I do. The insertion unit 43 inputs the encoded data and the code corresponding to the encoded data from the code buffer 42 and the code data amount counting unit 44 for each image frame. The insertion unit 43 inserts a code before the encoded data, and outputs it as a bit stream to the outside.

Hereinafter, the operation of the conventional video signal encoding apparatus will be specifically described with reference to FIG. In FIG. 5, in the conventional video signal encoding device, input video data is encoded by an encoding unit 41 and then temporarily stored in a code buffer 42. While the video data is being encoded by the encoding unit 41, the encoded data amount counting unit 44 counts the encoded data amount generated by the encoding unit 41. When the above-described encoding process is completed for one image frame, the inserting unit 43 inserts a code indicating the code data amount from the code data amount counting unit 44 before the encoded data from the code buffer 42. That is, the insertion unit 43 arranges the encoded data after the code indicating the generated code data amount and outputs it as a bit stream. As described above, in this conventional video signal encoding device, a bit stream including encoded data and a code indicating the amount of encoded data has been generated and output.
Accordingly, the conventional video signal decoding device that performs the decoding process detects a code indicating the amount of code data in the bit stream generated by the conventional video signal encoding device. This makes it possible to easily detect the target image frame reading position and perform frame skip processing.

[0006]

Even when the conventional video signal encoding apparatus as described above is used, the processing operation of the conventional video signal decoding apparatus cannot be easily performed.
Specifically, in the conventional video signal decoding device, it was possible to easily perform frame skip processing in the forward direction, which is the direction of normal reproduction, but it was not possible to perform frame skip processing in the reverse direction. It was still difficult. The reason is that the MPEG standard, 261 and H.261. In a compression coding method such as the H.263 standard, all data in a coded bit stream is read in the forward direction. Therefore, in the conventional video signal decoding device, the frame skip processing in the forward direction can skip to the target image frame while sequentially reading the code in the bit stream. However, in the conventional video signal decoding apparatus, when performing the frame skipping process in the backward direction, first, the reading position is skipped in the backward direction to the target image frame in the bit stream, and then the reading operation in the forward direction is performed again. To read the code. Therefore, the conventional video signal decoding apparatus has a problem in that skip and read operations must be repeatedly performed until a target image frame reading position can be specified. As described above, when a conventional video signal encoding device is used, a conventional video signal decoding device that performs decoding processing on a bit stream generated by the device easily converts a desired image frame in the bit stream into a desired image frame. Sometimes I could not access it. As a result, when the conventional video signal encoding device is used, the processing time in the conventional video signal decoding device cannot be reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has been made in consideration of a bit stream which enables easy access to a desired image frame even when accessing in the reverse direction. It is an object of the present invention to provide a video signal encoding apparatus and an encoding method capable of generating a video signal. Further, the present invention provides a video signal capable of easily accessing a desired image frame and reducing the time required for decoding even when accessing each image frame in a bit stream in the reverse direction. An object of the present invention is to provide a decoding device and a decoding method thereof.

[0008]

A video signal encoding apparatus according to the present invention is a video signal encoding apparatus for compressing and encoding an input video signal to generate and output a bit stream,
The video signal is compressed and encoded in image frame units, and address information indicating a position on the bit stream is assigned in image frame units, the assigned address information is encoded, and encoded data of the address information is encoded. Compression encoding means for adding to the compression encoded data of the corresponding image frame; address information storage means for storing encoded data of address information of the image frame compressed and encoded by the compression encoding means; One frame delay means for delaying the encoded data of the address information stored in the storage means by one image frame and outputting the delayed data to the compression encoding means, wherein the compression encoding means includes To the compressed and coded data of each image frame of
It is configured to add at least encoded data of the previous address information. With this configuration,
At least the encoded data of the previous address information is added to the compressed encoded data of each image frame and output as a bit stream. Therefore, when decoding the bit stream in image frame units,
By using the encoded data of the previous address information added to each image frame, it is possible to easily access a desired image frame even when accessing in the reverse direction.

A video signal encoding method according to the present invention is an encoding method for a video signal encoding apparatus for compressing and encoding an input video signal to generate and output a bit stream, wherein the compression encoding means comprises The signal is compressed and encoded in units of image frames, and address information indicating a position on the bit stream is added in units of image frames, the assigned address information is encoded, and encoded data of the address information corresponds to the data. A compression encoding step for adding to the compression encoded data of the image frame; an address information storage step for storing encoded data of the address information of the image frame compressed and encoded in the compression encoding step; and the address information storage step. The encoded data of the stored address information is time-delayed by one image frame and transmitted to the compression encoding means. Output encoding step, wherein the compression encoding unit adds encoded data of the immediately preceding address information acquired in the output step to the compressed encoded data of each image frame in the bit stream. ing. With this configuration, at least the encoded data of the immediately preceding address information is added to the compressed encoded data of each image frame, and the encoded data is output as a bit stream. Therefore, when the bit stream is decoded in units of image frames, the desired image can be obtained by using the encoded data of the previous address information added to each image frame, even when accessing in the reverse direction. Easy access to the frame.

A video signal decoding device according to the present invention is a video signal decoding device for decoding a compression-encoded bit stream into a video signal, wherein the data reading means reads out the data of the bit stream in image frame units. Address information extracting means for extracting encoded data of address information of at least one previous image frame from bit stream data output from the data reading means; and address information output from the address information extracting means. Address information storage means for storing coded data, read control means for controlling the data read means using coded data of address information stored in the address information storage means, and A decoder for decoding the data of the read bit stream. And a means. With this configuration, when a bit stream is decoded into a video signal, encoded data of address information of at least one previous image frame is extracted from data of each image frame in the bit stream, and Using the extracted encoded data, data of a desired image frame can be read and decoded. Therefore, even when accessing each image frame in the bit stream in the reverse direction, it is possible to easily access a desired image frame and reduce the time required for the decoding process.

A video signal decoding method according to the present invention is a decoding method of a video signal decoding device for decoding a compression-encoded bit stream into a video signal, wherein the data of the bit stream is converted into image frame units. A data reading step for reading, an address information extracting step for extracting encoded data of address information of at least one previous image frame from the data of the bit stream read in the data reading step, and an address information extracting step for extracting the address information extracted in the address information extracting step. An address information storing step of storing encoded data, and using the encoded data of the address information stored in the address information storing step, determining data of an image frame to be read next from the bit stream, and determining the determined image. Decode the data in the frame It has a Goka step. With this configuration, when a bit stream is decoded into a video signal, encoded data of address information of at least one previous image frame is extracted from data of each image frame in the bit stream, and Using the extracted encoded data, data of a desired image frame can be read and decoded. Therefore, even when accessing each image frame in the bit stream in the reverse direction, it is possible to easily access a desired image frame and reduce the time required for the decoding process.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a preferred embodiment of a video signal encoding apparatus and its encoding method according to the present invention, and a video signal decoding apparatus and its decoding method;

Embodiment 1 [Configuration of Video Signal Encoding Apparatus] FIG. 1 is a block diagram showing the configuration of a video signal encoding apparatus according to Embodiment 1 of the present invention. In FIG. 1, a video signal encoding apparatus according to the present embodiment includes an image compression unit 11 that performs a predetermined image compression process on a video signal input from the outside in units of image frames, and is connected to the image compression unit 11 and has a predetermined configuration. An entropy encoding unit 12 for performing an entropy encoding process, and a buffer 13 connected to the entropy encoding unit 12 for compressing an input video signal and sequentially outputting a bit stream obtained by encoding to an external device are provided. . Further, the video signal encoding device of the present embodiment is provided between the entropy encoding unit 12 and the buffer 13 and converts encoded data of address information in units of image frames on a bit stream for one image frame. A one-frame delay unit 14 and an address information storage unit 15 for outputting a time-delayed output to the entropy encoding unit 12 are provided. Here, the address information is position information indicating the (arrangement) position of the data of each image frame in the bit stream sequentially output from the buffer 13, and more specifically, the position information indicating the head position of the data. It is. Also, this address information
The image data is generated in the image frame unit by the image compression unit 11 or the entropy coding unit 12 and added to the corresponding image frame. The coded data is added to the compressed coded data of the corresponding image frame and stored in the buffer 13. Is output.

The image compression unit 11 converts the input video signal into a D
Image compression processing including CT (Discrete Cosine Transform) processing and quantization processing is performed for each image frame, and the compressed data subjected to image compression is output to the entropy encoding unit 12. The entropy encoding unit 12 performs entropy encoding processing (variable length encoding processing) on the compressed data in image frame units from the image compression unit 11.
To convert the data into a bit string to generate compressed encoded data in image frame units. The entropy encoding unit 12
The encoded data of the address information input from the one-frame delay unit 14 is added to the generated compressed encoded data and output to the buffer 13. Specifically, the entropy encoding unit 12 determines a predetermined area of the compression-encoded image frame,
Preferably, the address information is stored in the header area and output to the buffer 13.

The image compression unit 11 and the entropy encoding unit 12 compress and encode a video signal input from the outside in units of image frames, and convert address information indicating a position on the bit stream into units of image frames. The compression coding means is configured to code the assigned address information and add the encoded data of the address information to the compressed encoded data of the corresponding image frame. This compression encoding means is preferably of the MPEG standard, H.264. 2
61 standard, and H.61 standard. The input video signal is compressed and encoded based on a compression encoding method including the H.263 standard. Further, the compression encoding unit adds at least encoded data of the immediately preceding address information from the one-frame delay unit to the compressed encoded data of each image frame in the bit stream. As a result, the video signal encoding apparatus according to the present embodiment generates a bit stream that enables easy access to a desired image frame even when performing access in the reverse direction, as described in detail later. be able to.

The buffer 13 includes an entropy encoder 1
2 temporarily stores the data of one image frame of the bit stream output from and outputs it to the outside. The one-frame delay unit 14 outputs the encoded data of the address information from the address information storage unit 15 to the entropy encoding unit 12 with a time delay of one image frame. The address information storage unit 15 extracts and stores encoded data of the address information from the image frames stored in the buffer 13. That is, the address information storage unit 15 extracts and stores the encoded data of the immediately preceding address information encoded immediately before by the entropy encoding unit 12. Further, the address information storage unit 15 changes the encoded data of the stored address information according to the type of the image frame processed by the image compression unit 11 and the entropy encoding unit 12. Specifically, when the image compression unit 11 and the entropy coding unit 12 perform compression coding by combining intra-frame compression coding and inter-frame compression coding using, for example, a compression coding method of the MPEG standard, The information storage unit 15 stores two types of coded data of address information, that is, the coded data of the immediately preceding address information and the coded data of the address information of the immediately preceding intra-frame compression-coded image frame. Is stored. As described above, the encoded data of the two types of address information are stored and added to the compressed encoded data of the corresponding image frame by the entropy encoding unit 12, so that decoding and reproduction can be performed in a direction opposite to the normal reproduction. In addition, not only intra-frame compression-coded image frames but also inter-frame compression-coded image frames can be easily decoded.

[Structure of Bit Stream] The data structure of the bit stream generated and output by the video signal encoding apparatus according to the present embodiment will be specifically described with reference to FIGS. FIG. 2 is an explanatory diagram illustrating a configuration example of a bit stream output by the video signal encoding device illustrated in FIG. FIG. 3 is an explanatory diagram illustrating another configuration example of the bit stream output by the video signal encoding device illustrated in FIG. 2 and 3, the bit stream output from the buffer 13 is divided for each image frame data for clarity. As shown in FIG. 2, in the bit stream, a header area and a data area are provided for each image frame. Encoded data of the address information of the immediately preceding image frame is stored in a part of the header area, and compression-encoded image frame data is stored in the data area. Specifically, as shown in the figure, address information P indicating the head position of the header area on the bit stream is added to the data FD1 of the compression-encoded image frame. Similarly, data FD2, FD3, FD4
Address information Q, R, S, and T are assigned to the FD 5, respectively. For example, in a part of the header area of the data FD2, encoded data of the address information P of the immediately preceding image frame is stored. The coded data of these pieces of address information P, Q, R, S, and T are generated and added by the image compression unit 11 or the entropy coding unit 12 as described above, and are stored in the header area of the image frame. (Not shown). In addition to the above description, for example, a configuration in which encoded data of address information is stored in a user data area defined by the MPEG standard may be used. However, considering the easiness of data access at the time of decoding processing, the address information is, as shown in FIG.
It is desirable to store the image frame at a position (header area) as close as possible to the head position of the image frame.

As shown in FIG. 3, the bit stream includes data FD6 and FD9 subjected to intra-frame compression encoding and data FD7 and FD8 subjected to inter-frame compression encoding as image frame data. Data FD
6 is provided with address information P ′ indicating the start position of the header area on the bit stream. Similarly, data FD7, FD8, and FD9 have address information Q ',
R 'and S' are provided respectively. For example, the coded data of the address information P 'of the immediately preceding image frame and the address of the immediately preceding intra-frame compressed image frame are included in a part of the header area of the inter-frame compression-coded data FD7. And encoded data of the information P ′. Also, for example, in a part of the header area of the intra-frame compression-coded data FD9, the encoded data of the address information R 'of the immediately preceding image frame and the immediately preceding intra-frame compression-coded image frame And encoded data of the address information P ′. In addition to the above description, in an image frame that has been subjected to intra-frame compression coding, 1
A configuration in which encoded data of the address information of the image frame itself may be stored as encoded data of the address information of the image frame that has been compression-encoded in the immediately preceding frame. Alternatively, in an intra-frame compression-encoded image frame, the encoded data of the address information of the immediately preceding intra-frame compression-encoded image frame is stored without storing the encoded data.
A configuration in which only the encoded data of the address information of the immediately preceding image frame may be stored.

As described above, in the video signal encoding apparatus and the encoding method of the present embodiment, the address information storage unit 15
Stores encoded data of address information indicating a position of each image frame on a bit stream generated and output by the encoding apparatus, and outputs the encoded data to the one-frame delay unit 14. The one-frame delay unit 14 outputs the encoded data of the input address information to the entropy encoding unit 12 with a time delay of one image frame. Thereby, in the video signal encoding device and the encoding method according to the present embodiment,
The entropy encoding unit 12 can add encoded data of at least one previous address information on the bit stream to the data of the image frame currently encoded and output the data. As a result, the video signal encoding device and the encoding method of the present embodiment can generate a bit stream that allows easy access to a desired image frame even when performing access in the reverse direction. it can. In the above description, the case where the image compression unit and the entropy encoding unit are configured separately is described, but the embodiment is not limited to this, and the image compression unit and the entropy encoding unit are It may be configured integrally. Also,
Since the bit stream is a data sequence of image frames output on one time axis, address information is generated and added using time information indicating the time to decode or reproduce each image frame in the bit stream. A configuration may be used.

Embodiment 2 [Configuration of Video Signal Decoding Apparatus] FIG. 4 is a block diagram showing the configuration of a video signal decoding apparatus according to Embodiment 2 of the present invention. In the following description, for the sake of simplicity, a case will be described in which the bit streams shown in FIGS. 2 and 3 are decoded and output as video signals. It is also assumed that these bit streams are generated by the video signal encoding device shown in FIG. 1 and are recorded in a data recording device exemplified by a hard disk device in association with the address information of the image frame. . FIG.
In the video signal decoding apparatus according to the present embodiment, a data reading unit 31 that reads out bit stream data in image frame units, and encoded data of address information from the image frame data read out by the data reading unit 31 And an decoding unit 33 for decoding the data of the image frame input from the address information extracting unit. Further, in the video signal decoding device of the present embodiment, the data reading unit 3
1, an address information storage unit 35 connected to the address information extraction unit 32 and the read control unit 34 for controlling encoded data of the address information extracted by the address information extraction unit 32, and A reproduction control input unit 36 for inputting reproduction control information from outside and outputting the information to the read control unit 34 is provided.

The reproduction control input section 36 inputs reproduction control information for requesting normal reproduction or special reproduction including skip reproduction and reverse reverse reproduction by an external operation, for example, a user operation. The reproduction control information is output to the read control unit 34. The read control unit 34
In order to realize the operation or function requested by the input reproduction control information, the data read unit 31 is controlled. As will be described in detail later, the read control unit 34 reads the data of the image frame specified by the encoded data of the address information from the address information storage unit 35 based on the input reproduction control information. To instruct. The data read unit 31 directly accesses an external data recording device (not shown) based on an instruction from the read control unit 34, and reads bit stream data in image frame units. Data reading unit 31
Outputs the read image frame data to the address information extraction unit 32.

The address information extracting section 32 outputs the data of the image frame inputted from the data reading section 31 to the decoding section 33, and further extracts the encoded data of the address information contained in the data of the image frame. And outputs it to the address information storage unit 35. Each image frame contains
As described in the description of the first embodiment, encoded data of at least one previous address information is stored. Therefore, when image frame data is input from the data reading unit 31, the address information extracting unit 32 extracts the encoded data of the immediately preceding address information, and
5 is output. In addition, the bit stream conforms to the MPEG standard, H.264. H.261 standard, and H.264. In the case of a combination of the intra-frame compression coding and the inter-frame compression coding in the compression coding method including the H.263 standard, the address information extraction unit 32 outputs the address information of the immediately preceding address information from the input image frame data. The coded data and the coded data of the address information of the image frame that has been compression-coded in the immediately preceding frame are extracted and output to the address information storage unit 35. Accordingly, in the video signal decoding apparatus according to the present embodiment, when performing access in the reverse direction, not only the intra-frame compression-coded image frames but also the inter-frame compression-coded image frames can be easily decoded. Can be done.

The decoding unit 33 includes an address information extracting unit 32
And decodes the data of the image frame and outputs it as a video signal. This decoding unit 33 is, for example, an MPEG standard, H.264. H.261 standard, and H.264. It is configured to decode compression-coded image frame data based on a compression coding method including the H.263 standard. The address information storage unit 35 stores the encoded data of the address information from the address information extraction unit 32, and outputs the encoded data to the read control unit 34 so that the data can be used for the reproduction in the reverse direction when reading the bit stream data. . Note that, other than the above description, the address information extraction unit 32 is
The encoded data of the address information of the image frame may be extracted from the data of the image frame read out in step (1) and output to the readout control unit 34 via the address information storage unit 35.

[Decoding process of bit stream]
The decoding process in the video signal decoding device according to the present embodiment will be specifically described with reference to FIGS. First, a case will be described in which the video signal decoding apparatus of the present embodiment performs a decoding process on the bit stream shown in FIG. 2 and outputs the bit stream as a video signal. In the following description, it is assumed that the current access position of the data reading unit 31 is at a position on the bit stream specified by the address information R.
When performing normal reproduction, the read control unit 34 reads bit stream data in image frame units sequentially from the current access position specified by the address information R,
The data reading unit 31 is controlled so as to output to the address information extracting unit 32. At this time, the address information storage unit 35 sequentially updates the encoded data of the new address information and outputs the encoded data to the read control unit 34. These encoded data are those of the immediately preceding address information. Therefore, the read control unit 34 controls the data read unit 31 to read data for normal reproduction without performing control using the encoded data of the address information during normal reproduction.

When performing skip reproduction in the forward direction, the read control unit 34 skips the data read unit 31 by reading the header area by the number of frames to be skipped.
Instructs to read the data in the next header area. For example, when skipping two frames, the data reading unit 3
First, after reading the data of the header area of the data FD3 of the image frame from the current access position specified by the address information R, the data part in the data area is skipped and the data FD4 of the next image frame is read. Read the data in the header area. After that, the data reading unit 3
1 skips the data portion in the data area of the data FD4, reads the data in the header area of the data FD5 of the next image frame, and subsequently reads the data part in the data area of the data FD5 to extract address information. Output to the unit 32. Thereby, the data FD5 of the image frame skipped by two frames is decoded and reproduced.

When performing skip reproduction in the reverse direction or normal reproduction in the reverse direction, the read control unit 34 reads the next using the encoded data of the address information currently stored in the address information storage unit 35. Determine the image frame data. More specifically, the read control unit 34 inputs the encoded data of the address information P from the address information storage unit 35, and determines the current access position to the data read unit 31 based on the address information P of the immediately preceding image frame. Instruct to move to a position. Then, after moving from the access position specified by the address information R to the access position of the immediately preceding image frame specified by the address information P, the data reading unit 31 reads the data of the bit stream. Thereafter, for example, when further frame skipping is performed in the reverse direction, the data reading unit 31 reads the data FD1 of the image frame and outputs the data FD1 to the address information extracting unit 32. The address information extracting unit 32 extracts the encoded data of the address information X in the header area of the image frame data FD1, and updates the content stored in the address information storage unit 35.

Subsequently, when performing normal reproduction in the reverse direction,
The address information extracting unit 32 stores the image frame data FD1
To the decoding unit 33 to perform decoding and output a video signal. Further, when performing skip reproduction in the reverse direction, there is no need to output and display a video signal, so the address information extraction unit 32 does not need to output the data FD1 to the decoding unit 33. Further, the read control unit 34 stores the encoded data of the updated address information in the address information storage unit 35.
And instructs the data reading unit 31 to move to the next access position specified by the address information X again. As described above, in the video signal decoding apparatus of the present embodiment, by repeatedly moving the access position, the data access of the image frame in the reverse direction can be sequentially continued.

Next, the video signal decoding apparatus of the present embodiment
A case in which decoding processing is performed on the bit stream shown in FIG. 3 and output as a video signal will be described. As shown in FIG. 3, the data of the bit stream is, for example, MPE
The coding is performed by combining intra-frame compression coding and inter-frame compression coding in a compression coding scheme based on the G standard. When decoding such a bit stream, the address information extracting unit 32 encodes the encoded data of the address information of the immediately preceding image frame and the encoded information of the compression-encoded image frame of the immediately preceding frame. The data is extracted and output to the address information storage unit 35. Next, if the target image frame to be decoded and displayed is an image frame that has been subjected to intra-frame compression encoding, the image frame in the reverse direction is processed in the same procedure as in the case of decoding the bit stream shown in FIG. Data access can be performed.

If the target image frame is an inter-frame compression-encoded image frame, the read control unit 34 first sets the position specified by the address information of the immediately preceding intra-frame compression-encoded image frame. Is instructed to move from the current access position to the data reading unit 31. The data read unit 31 moves and changes the access position based on the instruction from the read control unit 34, and then reads the data of the image frame of the bit stream at the access position and reads the data from the read address information extraction unit 3
2 to the decoding unit 33. The decoding unit 33
The bit stream data from the address information extraction unit 32, that is, the data of the immediately preceding image frame stored in the address information storage unit 35 is input, decoded, and output as a video signal. As described above, in the video signal decoding apparatus of the present embodiment, when performing access in the reverse direction, not only the decoding processing of the intra-frame compression-coded image frames but also the decoding processing of the inter-frame compression-coded image frames are performed. It can be done easily.

As described above, in the video signal decoding apparatus and the decoding method according to the present embodiment, the data reading unit 31 reads data from a bit stream to be decoded in image frame units, and the address information extracting unit 32 reads data. The encoded data of the previous address information added at least to the data of the image frame unit is extracted, and the encoded data of the address information is stored in the address information storage unit 35. When performing access in the reverse direction, the read control unit 34 uses at least the encoded data of the immediately preceding address information stored in the address information storage unit 35,
Next, the data of the image frame to be read is determined, and the data reading unit 31 is instructed to read the data of the determined image frame. As a result, in the video signal decoding apparatus and the decoding method according to the present embodiment, even when accessing each image frame in the bit stream in the reverse direction, a desired image frame can be easily accessed and decoded. The time required for the conversion process can be reduced.

[0031]

As described above, according to the video signal encoding apparatus and the encoding method of the present invention, the address information storage means determines the position of the image frame unit on the bit stream generated and output by the encoding apparatus. The encoded data of the indicated address information is stored and output to the one-frame delay unit. The one-frame delay unit delays the input coded data of the address information by one image frame and outputs it to the compression coding unit. Thus, in the video signal encoding apparatus and the encoding method according to the present invention, the compression encoding unit adds the encoded data of the immediately preceding address information on the bit stream to the data of the image frame currently being compression encoded. Can be added and output. As a result, the video signal encoding device and the encoding method of the present invention can generate a bit stream that enables easy access to a desired image frame even when performing access in the reverse direction. .

In the video signal decoding apparatus and the decoding method according to the present invention, the data reading means reads data from the bit stream to be decoded in image frame units,
The address information extracting means extracts encoded data of the immediately preceding address information added to at least the data of the image frame unit, and the address information recording means stores the encoded data of the address information. When performing the access in the reverse direction, the read control unit determines the data of the image frame to be read next by using at least the encoded data of the previous address information stored in the address information storage unit. Instruct the data reading means to read the data of the determined image frame. As a result, in the video signal decoding apparatus and the decoding method according to the present invention, even when each image frame in the bit stream is accessed in the reverse direction, the desired image frame can be easily accessed and decoded. The time required for processing can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a video signal encoding device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a configuration example of a bit stream output by the video signal encoding device shown in FIG.

FIG. 3 is an explanatory diagram showing another configuration example of a bit stream output by the video signal encoding device shown in FIG. 1;

FIG. 4 is a block diagram illustrating a configuration of a video signal decoding device according to a second embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of a conventional video signal encoding device.

[Explanation of symbols]

 Reference Signs List 11 image compression unit 12 entropy encoding unit 13 buffer 14 1 frame delay unit 15 address information storage unit 31 data read unit 32 address information extraction unit 33 decoding unit 34 read control unit 35 address information storage unit 36 playback control input unit

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Claims (8)

[Claims] 1. A video signal encoding apparatus for compressing and encoding an input video signal to generate and output a bit stream, wherein the video signal is compressed and encoded in image frame units, and the video signal is encoded on the bit stream. Compression encoding means for assigning address information indicating a position in image frame units, encoding the assigned address information, and adding encoded data of the address information to compressed encoded data of a corresponding image frame; Address information storage means for storing the encoded data of the address information of the image frame compressed and encoded by the encoding means, and the encoded data of the address information stored in the address information storage means for a time corresponding to one image frame A one-frame delay means for delaying and outputting to the compression encoding means, wherein the compression encoding means Video signal encoding, wherein at least encoded data of the previous address information from the one-frame delay unit is added to the compressed encoded data of each image frame in the stream. apparatus. 2. The compression encoding means according to the MPEG standard,
H. H.261 standard, and H.264. The video signal encoding method according to claim 1, wherein the video signal is compressed and encoded by combining intra-frame compression encoding and inter-frame compression encoding based on a compression encoding scheme including the H.263 standard. Device. 3. The address information storage means stores encoded data of the address information of the immediately preceding image frame and encoded data of the address information of the image frame compressed and encoded in the immediately preceding frame. 3. The video signal encoding device according to claim 2, wherein: 4. A coding method for a video signal encoding apparatus for compressing and encoding an input video signal to generate and output a bit stream, wherein the compression encoding means compresses the video signal in image frame units. Encoding, and furthermore, assigning address information indicating a position on the bit stream in units of image frames, encoding the assigned address information, and converting the encoded data of the address information into the compressed encoded data of the corresponding image frame. A compression encoding step to be added; an address information storage step for storing encoded data of address information of the image frame compressed and encoded in the compression encoding step; and an encoding of the address information stored in the address information storage step. An output step of delaying data by one image frame and outputting the data to the compression encoding means, Wherein the compression encoding means adds encoded data of the immediately preceding address information obtained in the output step to compressed encoded data of each image frame in the bit stream. An encoding method for a signal encoding device. 5. A video signal decoding device for decoding a compression-encoded bit stream into a video signal, comprising: a data reading unit for reading data of the bit stream in image frame units; and an output from the data reading unit. Address information extracting means for extracting encoded data of address information of at least one previous image frame from the bit stream data obtained, and address information for storing encoded data of address information outputted from the address information extracting means. Storage means; read control means for controlling the data read means using encoded data of address information stored in the address information storage means; bit stream data read by the data read means And decoding means for decoding Video signal decoding device characterized by the above-mentioned. 6. The decoding means according to the MPEG standard, H.264.
H.261 standard, and H.264. The video signal decoding apparatus according to claim 5, wherein the data of the bit stream is decoded based on a compression coding scheme including the H.263 standard. 7. The method according to claim 1, wherein the address information extracting means includes a code of the address information of the image frame immediately before the data of the bit stream and a code of the address information of the image frame compressed and encoded in the immediately preceding frame. 7. The video signal decoding apparatus according to claim 6, wherein the video signal decoding apparatus extracts encoded data. 8. A decoding method of a video signal decoding device for decoding a compression-encoded bit stream into a video signal, comprising: a data reading step of reading data of the bit stream in image frame units; An address information extracting step of extracting encoded data of address information of at least one previous image frame from data of the bit stream read in the step; address information storing encoded data of the address information extracted in the address information extracting step Memory step,
And using the encoded data of the address information stored in the address information storing step to determine data of an image frame to be read next from the bit stream, and decoding the data of the determined image frame. A decoding method for a video signal decoding device, comprising: