From: Nicolas George <george@nsup.org>
To: FFmpeg development discussions and patches <ffmpeg-devel@ffmpeg.org>
Subject: Re: [FFmpeg-devel] Again pre-multiplied alpha
Date: Wed, 23 Jul 2025 16:11:45 +0200
Message-ID: <aIDtoSRuPCPiUQQE@phare.normalesup.org> (raw)
In-Reply-To: <20250723135626.1390296-1-ffmpeg@haasn.xyz>
Niklas Haas (HE12025-07-23):
> Changes since v1:
> - Correctly implement alpha mode tagging for JPEG XL
> - Set correct alpha mode for OpenEXR (which is always premultiplied)
> - Ensure -alpha_mode specified on the command line correctly propagates
> - Print out a warning when overriding the alpha mode explicitly
>
> Includes an unrelated fix for -chroma_sample_location also being ignored,
> since the fix for that was adjacent to the fix for the alpha mode field.
>
> Submitting this for re-evaluation. I decided in the end not to include full
> negotiation for the alpha mode, primarily because there is no filter currently
> existing that only handles one or the other.
Also, negotiation is fragile and needs tests.
But can you point to where the code that prevents a component not
ready from receiving a premultiplied frame is?
Regards,
--
Nicolas George
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next prev parent reply other threads:[~2025-07-23 14:11 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-07-23 13:47 [FFmpeg-devel] (no subject) Niklas Haas
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 01/18] avutil/frame: add AVFrame.alpha_mode Niklas Haas
2025-07-23 16:00 ` Kacper Michajlow
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 02/18] fftools/ffprobe: add support for AVFrame.alpha_mode Niklas Haas
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 03/18] avfilter/vf_showinfo: print alpha mode when relevant Niklas Haas
2025-07-23 16:11 ` Kacper Michajlow
2025-07-24 11:19 ` Niklas Haas
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 04/18] avcodec/avcodec: add AVCodecContext.alpha_mode Niklas Haas
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 05/18] avcodec/encode: enforce alpha mode compatibility at encode time Niklas Haas
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 06/18] avcodec/png: set correct alpha mode Niklas Haas
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 07/18] avcodec/exr: " Niklas Haas
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 08/18] avcodec/libjxl: " Niklas Haas
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 09/18] avcodec/libjxlenc: also attach extra channel info Niklas Haas
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 10/18] avcodec/jpegxl: parse and signal correct alpha mode Niklas Haas
2025-07-23 16:19 ` Kacper Michajlow
2025-07-24 11:13 ` Niklas Haas
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 11/18] avfilter/vf_scale: don't ignore incoming chroma location Niklas Haas
2025-07-24 11:16 ` Niklas Haas
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 12/18] fftools/ffmpeg_enc: don't ignore user selected " Niklas Haas
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 13/18] fftools/ffmpeg_enc: forward frame alpha mode to encoder Niklas Haas
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 14/18] avfilter/vf_premultiply: tag correct alpha mode on result Niklas Haas
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 15/18] avfilter/vf_alphamerge: tag correct alpha mode Niklas Haas
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 16/18] avfilter/vf_overlay: respect alpha mode tagging by default Niklas Haas
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 17/18] avfilter/vf_setparams: add alpha_mode parameter Niklas Haas
2025-07-23 13:47 ` [FFmpeg-devel] [PATCH v2 18/18] avfilter/vf_libplacebo: add an alpha_mode setting Niklas Haas
2025-07-23 14:11 ` Nicolas George [this message]
2025-07-23 15:18 ` [FFmpeg-devel] Again pre-multiplied alpha Niklas Haas
2025-07-23 17:02 ` Nicolas George
2025-07-24 11:11 ` Niklas Haas
2025-07-24 14:59 ` Nicolas George
2025-07-24 20:58 ` Niklas Haas
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