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• avcodec/hevcdec : Output MD5-message in one piece

  22 juillet 2022, par Andreas Rheinhardt

  avcodec/hevcdec : Output MD5-message in one piece
  Otherwise, there is no guarantee that the various av_log-messages
  
  are not interrupted by another log statement. The latter may originate
  
  from anywhere else, even the HEVC decoder itself, as happens when
  
  one uses frame-threading to decode the BUMPING_A_ericsson_1.bit
  
  sample from the FATE-suite.
  Furthermore, the earlier approach suffered from the fact that
  
  various parts of the logmsg were output with different loglevels
  
  and that checking stopped after having encountered the first
  
  plane with MD5 mismatch, although it is probably interesting to
  
  know whether other planes are incorrect, too.
  Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
  

  • [DH] libavcodec/hevcdec.c

• How to use -vf format="gray" in ffmpeg python

  22 août 2022, par user19551045

  I am trying to use the -vf format="gray" in ffmpeg-python and I can't seem to get the syntax right. From what I have seen, ffmpeg-python has a set of filter_name options you can use, and then there is also the option to use .filter_() to just put in the ffmpeg commands directly in.

  


  I have tried using both and seem to get the same error, where ffmpeg-python wants me to declare a filter_name and from what I am seeing in the documentation, format=gray doesn't fall under any of the filter_name options.

  


  If I take this approach, it works :

  


  (
        ffmpeg.input(img_seq_template, framerate=framerate, **input_options)
        .filter("format", "gray")
        .output(filename=output_path, **output_options)
        .run(overwrite_output=True)
   )


  


  However, I want to also use a dictionary in the filter(), which then requires me to put in a filter_name. The goal would be to have something like below working :

  


  filter_options = {'format' : 'gray'}

(
        ffmpeg.input(img_seq_template, framerate=framerate, **input_options)
        .filter(filter_name = "some_filter_name", **filter_options)
        .output(filename=output_path, **output_options)
        .run(overwrite_output=True)
    )


  


  Any ideas on what I could put into the filter_name to get this running would be amazing ! All suggestions welcome, thanks so much !

  


• Missing piece between libjpeg-turbo & h264 ffmpeg C/C++

  15 octobre 2022, par Nelstaar

  On the left side I have a buffer with decoded pixels that I can get in two formats :

  


  RGB interleaved/packed where bytes in buffer are R0G0B0R1G1B1....

  


  or

  


  YUV444 interleaved/packed where bytes in buffer are Y0U0V0Y1U1V1...

  


  (JCS_RGB or JCS_YCbCr in jpeglib.h)

  


  (Please note that I use libjpeg-turbo because I need to decompress a cropped region of the image. (jpeg_crop_scanline()))

  


  On the right side I have x264 codec via ffmpeg that support only planar pixel formats :

  


  yuv420p, yuvj420p, yuv422p, yuvj422p, yuv444p, yuvj444p, nv12, nv16, nv21, yuv420p10le, yuv422p10le, yuv444p10le, nv20le

  


  yuv444p where bytes in buffer are Y0Y1Y2...U0U1...V0V1...

  


  according to ffmpeg -h encoder=libx264

  


  I have some ideas already :

  


  

  • Decompress Jpeg to RBG888 in buffer 1 then libswscale to yuv420p in buffer 2 and encoding. (copy)

  


  • Decompress Jpeg to YUV444 interleaved in buffer 1 then SSSE3 magic in buffer 1 to yuv444p and encoding. (no copy)

  


  • or else.

  


  


  What would be the most effective fastest way ?

  


  I which to avoid buffer copy.

  


  Movie have the same width & height than Jpegs.