IDR, CRA and BLA are all "IRAP" frames, ie. "Intra Random Access Pictures", which means you can start decoding from there. The differences lie in their usage - a CRA frame could be followed by inter pictures in coding order with reference frames not available to the decoder, and must therefor be discarded (TFD frames, Tagged for Discard), which is not allowed for IDR. BLA are quite similar to CRA, except they convey a special meaning that the bitstream may have been stitched at that point.
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LAV Filters - open source ffmpeg based media splitter and decoders
Last edited by nevcairiel; 17th March 2018 at 11:10.
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