Re: [FFmpeg-devel] [PATCH v4 3/7] avcodec/webp_parser: parse each frame into one packet
On Wed, Jul 26, 2023 at 2:36 PM Tomas Härdin wrote: > > tis 2023-07-25 klockan 16:18 +0200 skrev Thilo Borgmann: > > Am 25.07.23 um 14:24 schrieb Tomas Härdin: > > > > +// Extremely simplified key frame detection: > > > > +// - the first frame (containing headers) is marked as a key > > > > frame > > > > +// - other frames are marked as non-key frames > > > > > > Is there a more proper way of doing this? > > > > All frames (except the ANMF chunks) are INTRA, and all of them have a > > WEBP tag. > > Whereas all ANMF chunks are in the same WEBP chunk as their reference > > frame. > > So it should really be as simple as it is to mark all WEBP frames as > > key frames as the code does. > > What more dedicated do you have in mind? > > Nah mostly just curious. It just feels so weird when VP8 intra already > exists. Maybe I'm missing something. Browsers already support VP8 after > all. > We wanted something lighter weight (memory, cpu) for an image format rather than going full blown video. Lossless also factored into this. > > The logic as-is works with all samples I have, animated and not. > > Seems to also align well with their example file layouts. > > You have a more weird one? > > Nope ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-devel] [PATCH v4 3/7] avcodec/webp_parser: parse each frame into one packet
tis 2023-07-25 klockan 16:18 +0200 skrev Thilo Borgmann: > Am 25.07.23 um 14:24 schrieb Tomas Härdin: > > > + // Extremely simplified key frame detection: > > > + // - the first frame (containing headers) is marked as a key > > > frame > > > + // - other frames are marked as non-key frames > > > > Is there a more proper way of doing this? > > All frames (except the ANMF chunks) are INTRA, and all of them have a > WEBP tag. > Whereas all ANMF chunks are in the same WEBP chunk as their reference > frame. > So it should really be as simple as it is to mark all WEBP frames as > key frames as the code does. > What more dedicated do you have in mind? Nah mostly just curious. It just feels so weird when VP8 intra already exists. Maybe I'm missing something. Browsers already support VP8 after all. > The logic as-is works with all samples I have, animated and not. > Seems to also align well with their example file layouts. > You have a more weird one? Nope /Tomas ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-devel] [PATCH v4 3/7] avcodec/webp_parser: parse each frame into one packet
On Tue, Jul 25, 2023 at 7:18 AM Thilo Borgmann wrote: > > Am 25.07.23 um 14:24 schrieb Tomas Härdin: > >> +// Extremely simplified key frame detection: > >> +// - the first frame (containing headers) is marked as a key > >> frame > >> +// - other frames are marked as non-key frames > > > > Is there a more proper way of doing this? > > All frames (except the ANMF chunks) are INTRA, and all of them have a WEBP > tag. > Whereas all ANMF chunks are in the same WEBP chunk as their reference frame. > So it should really be as simple as it is to mark all WEBP frames as key > frames as the code does. > What more dedicated do you have in mind? > > The logic as-is works with all samples I have, animated and not. > Seems to also align well with their example file layouts. > You have a more weird one? > > > > Looking briefly at the spec > > one wonders why they didn't just use regular VP* inter frames.. > > I assume the whole canvas idea could be more beneficial than vp8 inter - but > otoh I don't know about vp8 compositing capabilities, if any.. > This was more in alignment with gif and allowed for a simpler reference structure. WebP also supports lossless and mixing lossy/lossless so this method makes the behavior consistent between VP8 and VP8L. ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-devel] [PATCH v4 3/7] avcodec/webp_parser: parse each frame into one packet
Am 25.07.23 um 14:24 schrieb Tomas Härdin: + // Extremely simplified key frame detection: + // - the first frame (containing headers) is marked as a key frame + // - other frames are marked as non-key frames Is there a more proper way of doing this? All frames (except the ANMF chunks) are INTRA, and all of them have a WEBP tag. Whereas all ANMF chunks are in the same WEBP chunk as their reference frame. So it should really be as simple as it is to mark all WEBP frames as key frames as the code does. What more dedicated do you have in mind? The logic as-is works with all samples I have, animated and not. Seems to also align well with their example file layouts. You have a more weird one? Looking briefly at the spec one wonders why they didn't just use regular VP* inter frames.. I assume the whole canvas idea could be more beneficial than vp8 inter - but otoh I don't know about vp8 compositing capabilities, if any.. -Thilo ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-devel] [PATCH v4 3/7] avcodec/webp_parser: parse each frame into one packet
> + // Extremely simplified key frame detection: > + // - the first frame (containing headers) is marked as a key > frame > + // - other frames are marked as non-key frames Is there a more proper way of doing this? Looking briefly at the spec one wonders why they didn't just use regular VP* inter frames.. /Tomas ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
