Hi, On Thu, May 22, 2025 at 8:33 AM Ramiro Polla <ramiro.po...@gmail.com> wrote:
> On Thu, May 22, 2025 at 1:59 PM Ronald S. Bultje <rsbul...@gmail.com> > wrote: > > On Wed, May 21, 2025 at 9:34 AM Timothée < > > timothee.informati...@regaud-chapuy.fr> wrote: > > > I am interested in expanding ffmpeg's capabilities to extract > > > low-level data from video codecs. Specifically, I'd like to implement > > > functionality that would allow exporting frame data, macroblock > > > information, quantization tables, and similar codec-specific elements > > > to binary files for further analysis. > > > > > > After searching through the documentation and existing features, I > > > haven't found similar functionality, though I may have missed > > > something. Has this been implemented before, or are there related > > > features I should examine? > > > > Some older codecs implement minor variants for this, e.g. grep > > for AV_FRAME_DATA_MOTION_VECTORS, which attaches a frame's motion vectors > > to the picture data. I believe there's an example app and possibly a > filter > > to overlay MVs on top of the video frame based on this concept. You could > > extend this to cover other (macro)block info. There used to be a variant > of > > this for quant-tables also but I can't find it, maybe it was removed. > > If I recall correctly, we wanted to move away from exporting more of > this kind of codec-specific information as picture data. > > Timothée, this kind of feature depends a lot on the codec that you > want to work with. It will also depend on which syntax elements you > need from the codec. In FFmpeg, there is the CBS code which describes > the bitstream for a few codecs, which might help you. I believe CBS only describes headers, not block data? Ronald _______________________________________________ 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".
