Hi,

I am currently trying to interpret the index data of HuffYuv/PCM AVI files written by FFmpeg. If the file is larger than 2GiB an "AVIX" RIFF chunk is added for each 2GiB-block, each of these blocks gets an OpenDML chunk index "ix00" and an OpenDML super index chunk "indx" is written for each stream that contains the file offset of the according chunk indexes together with its size and total duration.

For this super index "duration" entry the documentation I have found states that it shall be the "time span in stream ticks" [1]. FFmpeg seems to write the chunk count instead which is correct for video streams where one data chunk "00dc" corresponds to one frame. For audio streams one data chunk "01wb" usually contains multiple samples.

I guess for audio streams the "duration" should be multiplied by the samples-per-chunk factor in avienc.c to allow third-party applications to jump to the correct AVIX RIFF segment based on a given timestamp.

Any comments?

Regards,
Tobias


Links:
[1] http://www.the-labs.com/Video/odmlff2-avidef.pdf

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