Fix growing AVC file descriptor header #7
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emcodem
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As bespoke, some comments from my side
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Why assert only in case of CW_UNKNOWN_CLIP_TYPE? Should this BMX_ASSERT(false) in the default case instead?
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The assert should really only be executed for CW_UNKNOWN_CLIP_TYPE. However, I have now added the remaining clip types to avoid any confusion in the future.
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Why is update_header only used in the case of AVC_CAVLC_444_INTRA? Could the other formats also benefit from it?
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The switch case contains all AVC from Baseline to CAVLC 444 Intra.
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Because you asked about this when we talked last time: personally i like the idea of this patch that the core library for OP1AFile is not changed entirely but only a function added. Deep changes in the core library will most likely lead to unforeseen and hard to test behaviour. In a very old PR from myself, Philip commented a similar approach as reasonable. https://sourceforge.net/p/bmxlib/discussion/general/thread/feb92cc5/#86e1
Update the MXF header metadata after the first frame so that the parsed AVC descriptor metadata are available from the beginning.
Hi,
the AVC descriptor metadata were parsed together with the first frame. However, the MXF header has already been written at this point and only placeholders have been used. Video editors, e.g. Avid or Adobe, cannot open the file without the corresponding descriptor metadata.
This patch updates the MXF header metadata after the first frame so that growing files can be read.
Thomas