JP2003304540A - Moving picture data encoder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a moving picture data encoder for encoding moving pictures without wastefully implementing motion vectors. <P>SOLUTION: In the case that data for motion vector management are produced on the basis of a picture type and an inspection means does not utilize it when a valid motion vector file exists, a motion vector searching means generates motion vector data, decides a name of a file on the basis of an object picture number, a reference picture number, a searching range, and a type of a motion vector, and stores the file. The encoder encodes a moving picture by using a motion vector data at high speed when encoding the same moving picture. <P>COPYRIGHT: (C)2004,JPO

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a moving image data encoding apparatus, and more particularly to a method for executing encoding processing in parallel using a plurality of processors and re-encoding. The present invention relates to a method for managing a motion vector when performing the operation. 2. Description of the Related Art Conventionally, moving picture coding methods, especially MPEG
As an encoding method, there is known a method of performing encoding using a plurality of processors described in Japanese Patent Application Laid-Open No. 8-294130. Japanese Patent Laying-Open No. 8-294130 discloses a method for speeding up the MPEG encoding process by dividing and distributing the encoding process to a plurality of processors. [0003] In the conventional technology, a plurality of processors perform encoding independently of each other. In MPEG coding, there is a loss in the coded image data itself. Furthermore, in order to maintain the quality of the encoded video data and to reduce the encoded data to a predetermined size or less, the encoding conditions of the image data may be changed and the encoding may be performed again. An encoding processing device of a certain storage system frequently performs re-encoding processing with changing encoding conditions. In addition, in the MPEG encoding process, a very large number of calculations are required as the motion vector search calculation affects the encoding processing speed. In addition, since the own processor or another processor recalculates the already calculated motion vector data, there is a problem that the motion vector calculation lowers the speed of the entire encoding process. SUMMARY OF THE INVENTION It is an object of the present invention to perform high-speed video coding by managing and storing the obtained motion vectors and reusing the motion vectors that can be used at the time of coding to omit useless calculations. I do. [0006] In order to solve this problem, the present invention creates motion vector management information based on the type of encoding created by the code type determining means, and creates the created motion vector management information. , The presence or absence of a valid motion vector in the storage means is determined by the motion vector inspection means. If there is a valid motion vector, the motion vector is used. If there is no valid motion vector, a valid motion vector is calculated by the motion vector search means. The calculated motion vector is added to the motion vector management information, and encoding is performed using an encoding unit using the motion vector. The encoded stream is output by the output unit. As a result, it becomes possible to speed up the motion vector search processing in the moving picture coding apparatus according to the state. FIG. 1 shows the configuration of a moving picture coding apparatus according to an embodiment of the present invention. Hereinafter, the configuration and functions of the video encoding device will be described with reference to FIG. The processor 14, memory 12, image input unit 10, image output unit 11, disk 13, stream output unit 15, and RAM 16 are all connected by a local bus. The processor 14 is an arithmetic processing unit.
It operates according to the encoding processing program 161 stored in the AM 16. [0010] The memory 12 stores parameters and data necessary for the encoding process. During the encoding process, information for encoding control is stored. Note that the RAM 16 and the memory 12 may be the same device. The image input unit 10 includes a digital VTR 102 and a capture unit 101. Digital VTR10
2, the moving image data to be encoded is recorded. The capture unit 101 converts the video signal output from the digital VTR 102 into a predetermined format and records the converted video signal on a disc. The image output unit 11 includes a decoder unit 111 and a digital monitor 112. The bit stream 132 stored in the disk 13 is transferred to the decoder unit 111 under the control of the processor 14. Decoder section 111
Decodes the bit stream 132 and outputs a reproduced video signal. The digital monitor 112 displays the reproduced video signal output from the decoder unit 111. The disk 13 stores a bit stream 132 obtained by encoding an image and a motion vector file 131. FIG. 2 shows the data format of the motion vector file 131.
Shown in The stream output unit 15 outputs the bit stream 132 stored on the disk 13. Next, the encoding process performed by the moving picture encoding apparatus will be described. In order to perform MPEG2 encoding, an original moving image is input by an image input means, and its features are extracted.
The picture type and the GOP structure to be encoded are determined by the code type determining means by scene detection, repeated image detection, and the like. The picture type data shown in FIG. 3 is created from the determined GOP structure. The picture types include an I picture which is coded only with the target picture, a P picture which refers to the immediately preceding I or P picture, and a B picture which refers to a straight line and the immediately succeeding I or P picture. Encoding is performed using a motion vector performing forward reference in a P picture, and a motion vector performing forward and backward reference in a B picture. When the current picture, the reference picture, and the search range are the same, the motion vectors of the source images have the same result each time. Change the motion vector file stored on the disc according to the target picture number and the reference picture number, the motion vector search range and the type of motion vector,
By inspecting the presence or absence and the data, it is possible to determine whether valid motion vector data has already been calculated. FIG. 5 is a flowchart for creating motion vector information, FIG. 6 is a flowchart for motion vector inspection,
FIG. 7 shows a block diagram of the encoding process. The motion vector information creating means 731 creates motion vector management information according to the processing shown in FIG. The motion vector inspection means 732 inspects the existing motion vector file 740 according to the processing of FIG. 6, and if there is a valid motion vector, the motion vector file 740 is stored in the motion vector data table 734 on the memory by the motion vector reading means 733. Read. If there is no valid motion vector data, motion vector data is created from the source image by the motion vector search means 735 and stored in the motion vector data table on the memory. Save to vector file 740. FIG. 4 is a flowchart showing a main process according to the embodiment of the present invention. Hereinafter, the processing of FIG. 4 will be described. It is determined which code type the image to be coded is an I picture, a B picture, or a P picture (S
400). The code type is determined for all the images to be coded (S401). A variable i indicating the number of an image to be encoded is initialized (S402). In order to prepare a motion vector necessary for encoding a GOP, the code type of the i-th picture is determined one by one (S420). If the picture is a B picture, a backward motion vector test is performed because a backward motion vector and a forward motion vector are required (S430). If there is a backward motion vector file, the motion vector file is read (S433). If there is no backward motion vector file, a backward motion vector search is performed (S431), and then the backward motion vector is written to the file (S43).
2). Next, since a forward motion vector is required,
A forward motion vector test is performed (S440). If there is a forward motion vector file, the motion vector file is read (S443). If there is no forward motion vector file, a backward motion vector search is performed (S441), and then the forward motion vector is written to the file (S44).
2). If the picture is a P-picture, only a forward motion vector is required, so a forward motion vector check is performed (S440). If there is a forward motion vector file, the motion vector file is read (S443). If there is no forward motion vector file, a backward motion vector search is performed (S441), and then the forward motion vector is written to the file (S44).
2). If the picture is an I-picture, no motion vector is required for encoding, so the process proceeds to S450. To determine whether the motion vector of the GOP to be coded is ready,
It is determined whether the picture is the last picture of the OP (S45).
0). If it is not the last picture of the GOP, 1 is added to the variable i to advance the picture by one (S47).
0), and returns to the determination of the type of the next i-th code (S42).
0). If it is the last picture of the GOP, the motion vector required for encoding is ready, so that GOP is encoded (S451). Thereafter, it is determined whether the GOP is the last GOP (S460). If it is not the last GOP, 1 is added to the variable i to advance the picture by one (S470), and the type of the i-th code is returned to the judgment (S420). If it is the last GOP, the encoding process ends. As described above, by managing and storing motion vectors in moving image coding, it is not necessary to search for a motion vector when coding an image again, so that the coding process can be speeded up. It should be noted that the present invention is not limited to the above embodiment, but can be arbitrarily modified. For example, the present invention can also be applied to a case where the motion vector search means uses a plurality of processors 14 to parallelize the motion vector search processing to increase the speed. In this embodiment, the motion vector data is stored on the disk, but may be stored on another storage medium such as a memory. As described above, according to the present invention, motion vector data is recorded and managed in a file derived from the searched motion vector data according to the target picture, reference picture, search range and type of motion vector. By doing so, it becomes possible to perform moving image data encoding processing at high speed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration diagram of an encoding device according to an embodiment of the present invention. FIG. 2 is a diagram showing a data format of a motion vector file according to the embodiment of the present invention. FIG. 4 is a diagram showing a picture type data format in the embodiment of the present invention. FIG. 4 is a flowchart of a main process in the embodiment of the present invention. FIG. 5 is a flowchart of a motion vector information creation in the embodiment of the present invention. FIG. 7 is a block diagram of an encoding process according to an embodiment of the present invention. DESCRIPTION OF SYMBOLS 10 Image input unit 11 Image output unit 12 Memory 13 Disk 14 Processor 15 Stream output unit 16 RAM 101 Capture unit 102 digital VTR 111 decoder unit 112 digital monitor 121 picture Ip data 122 Motion vector management information 131 Motion vector file 132 Bit stream 141 Encoder 142 Motion vector management unit 161 Encoding processing program 700 Code type determination unit 710 Encoding unit 720 Output unit 731 Motion vector information creation unit 732 Motion vector inspection unit 733 Motion vector reading means 734 Motion vector data table 735 Motion vector searching means 736 Motion vector writing means 740 Motion vector file

Continuation of front page    F term (reference) 5C059 KK15 MA00 MA05 MA14 NN01                       NN03 NN11 PP05 PP06 PP07                       SS12 TA62 TB04 TC02 TC12                       TC27 TC41 TC42 TD11 UA02                       UA38                 5J064 AA03 BA13 BB13 BC01 BC02                       BC03 BC29 BD01

Claims (1)

1. An image input unit for inputting a designated source image, a code type determining unit for determining a type of encoding of the source image, and the source image based on the type of encoding Motion vector information creating means for creating the motion vector management information, storage means for storing the created motion vector management information and the motion vector, and storage means having an effective motion vector based on the motion vector management information. Motion vector inspecting means for determining whether or not the effective motion vector is stored in the storage means, a motion vector searching means for searching for a motion vector of the source image, A motion vector writing unit that stores the motion vector management information in the storage unit together with the motion vector management information; A motion vector reading unit that reads a motion vector from the storage unit; an encoding unit that encodes the source image using a motion vector based on the type of encoding; and a stream that encodes the source image. A moving image data encoding device comprising output means.