Transcoder, transcoding method, decoder, and decoding method

Abstract

The invention provides a transcoder and a transcoding method capable of quickly transcoding video data of different compressive encoding schemes without increasing the circuit scale. A transcoder including a decoder (1), a syntax conversion section (2), and an encoder (3) is used. The decoder (1) decodes video data compressively encoded in accordance with the MPEG-2 scheme, extracts motion vectors produced in accordance with the MPEG-2 scheme, and performs dequantization on the video data other the motion vectors. The syntax conversion section (2) converts the syntax of the video data obtained from the decoder (1) to the H.264 scheme. The encoder (3) quantizes the video data obtained as a result of syntax conversion and compressively encodes it along with the extracted motion vectors in accordance with the H.264 scheme. The encoder (3) adds a descriptor indicating that the motion vectors have been produced in accordance with the MPEG-2 scheme to the obtained data.

Description

technical field [0001] The present invention relates to a code converter and a code conversion method for transcoding image data, and further relates to a decoder and a decoding method for reproducing the code-converted image data. Background technique [0002] Conventionally, the MPEG2 system has been known as one of the methods for compressing and encoding video images. The MPEG2 method can suppress image quality degradation and compress video data, so it is widely used in various fields such as DVD and digital broadcasting. [0003] In recent years, a new compression encoding method called the H.264 method has also been developed. According to the H.264 method, it is possible to compress and encode video at a higher compression rate than the MPEG2 method. For example, when the same video data is compressed and encoded with the same level of image quality by the MPEG2 method and the H.264 method, the data volume of the video data compressed by the H.264 method is half th...

AI Technical Summary

Problems solved by technology

[0012] However, the purpose of the latter transcoder is not to change the compression encoding method, but only to compress the data volume of MPEG2 video data.

That is, the latter transcoder does not perform transcoding that takes into account differences in syntax (syntax) or motion compensation between different compression coding methods, and cannot perform conversion from MPEG2 video data to H.264 video data. code conversion

Images