Fix HEVC hvc1 tagging: set stream codec_tag and cover all HEVC encoders#154
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AlvinShenSSW wants to merge 1 commit into
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Fix HEVC hvc1 tagging: set stream codec_tag and cover all HEVC encoders#154AlvinShenSSW wants to merge 1 commit into
AlvinShenSSW wants to merge 1 commit into
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The existing hvc1 tagging set the tag via stream.options['tag'], but PyAV/ ffmpeg treats that as an encoder private option and silently ignores it, so HEVC output in ISOBMFF containers (mp4/mov/m4v) stayed tagged 'hev1'. Apple's AVFoundation (Finder thumbnails, QuickLook, QuickTime, Safari) rejects 'hev1'. Verified with PyAV 16.1.0: stream.options['tag']='hvc1' yields 'hev1', while stream.codec_tag='hvc1' yields 'hvc1'. Set codec_tag on the stream instead so the muxer FourCC is actually written, and apply it to all HEVC encoders (libx265, hevc_nvenc, hevc_amf, hevc_qsv, hevc_videotoolbox), not just hevc_videotoolbox. Metadata-only change; non-Apple players accept both tags.
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Problem
HEVC output in ISOBMFF containers (mp4/mov/m4v) is tagged
hev1, which Apple's AVFoundation rejects — no Finder thumbnails / QuickLook previews, and no playback in QuickTime or Safari. The intended tag ishvc1.The current code sets this through the encoder options dict:
But PyAV/ffmpeg treats
stream.optionsas encoder private options and silently ignores an unknowntagkey, so the output stayshev1. (#153 widens this to all HEVC encoders but keeps the same ineffective mechanism, so it doesn't actually change the tag either.)Verification (PyAV 16.1.0)
codec_tag_stringstream.options['tag'] = 'hvc1'hev1❌stream.codec_tag = 'hvc1'hvc1✅hev1Confirmed end-to-end through
VideoWriterwith bothlibx265andhevc_nvenc: the muxed output goes fromhev1tohvc1.Fix
Set the tag via the stream's
codec_tag(the muxer FourCC) instead of encoder options, and apply it to all HEVC encoders (libx265,hevc_nvenc,hevc_amf,hevc_qsv,hevc_videotoolbox) when writing mp4/mov/m4v. Metadata-only change; non-Apple players accept both tags.Supersedes #153.