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aizvorski / h264bitstream

A complete set of functions to read and write H.264 video bitstreams, in particular to examine or modify headers.
GNU Lesser General Public License v2.1
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reading and writing slice data #8

Open serhan-gul opened 8 years ago

serhan-gul commented 8 years ago

h264_slice_data.c file provides some functions for extracting slice and macroblock information but it is not implemented in h264_analyze. Is there going to be a patch for this anytime soon? Would it be straightforward to modify slice data functions or is there still a lot of work to do? It is regarded as a "large project" in the readme file, that's why I'm asking.

aizvorski commented 8 years ago

Serhan,

The code in h264_slice_data.c needs work before it would be usable. The following missing functions need to be implemented:

They are just stubs right now. Most are relatively easy.

There would also need to be a data structure to store macroblocks - the macroblock_t struct describes what is in one macroblock, but there would have to be an array of them for a whole slice (with some way to index it - scan order, and convert scan order to row/column, plus utility functions to find neighbors of a given mb).

That's all I can think of at the moment. The code that is there now does cover a whole lot of what the standard does, it just needs the stubs to be filled in, and a bunch of testing.

serhan-gul commented 8 years ago

Alex,

Thanks for the list of functions and detailed explanation. I will definitely try to implement them sometime. Although (open-source) parsers do exist for HEVC, I couldn't find any parser other than yours for H.264. It is definitely interesting.

nathankopp commented 5 years ago

Has anyone done any work on this? I'm trying to write some code that will parse (but not decode) an h264 stream, so that I can extract the motion vectors quickly for analysis.