from_lavc_vid_conv: guard NULL conversion in get_av_to_uv_conversion - #504
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get_av_to_uv_conversion_int() can return a valid struct with conversion == NULL (direct pixfmt map, decoder, or CUDA early-return paths), but since ecd4c53 the VERBOSE message unconditionally dereferences ret->conversion->uv_codec, SEGV when -t file: decodes to a directly-mapped format. Regression introduced in ecd4c53.
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I was able to reproduce this with The fix looks good to me. |
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When running encoder viability tests with file input to gauge codec suitability, I ran into an UltraGrid SEGV situation.
Root cause:
get_av_to_uv_conversion_int() can return a valid struct with conversion == NULL (the direct pixfmt-map, decoder, or CUDA early-return paths).
Since ecd4c53, the VERBOSE message in get_av_to_uv_conversion() unconditionally dereferences ret->conversion->uv_codec, crashing whenever a decoder emits a directly-mapped format (e.g. HEVC VAAPI -> NV12)
"-t file:$arg" was my vector for discovering it.
Fix:
guard the dereference. When conversion is NULL, fall through to the plain "converting A to B" message (which is accurate for those paths). Doing the same short-circuit elsewhere is unnecessary — the consumer in do_av_to_uv_conversion() already guards conversion != NULL.
I performed a local build with the patched file, ran through a couple of tests and it seemed OK.
It seems to have been introduced in ecd4c53.