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• ffmpeg converting mp4 to gif with color palette results in truncated video

  6 décembre 2019, par Tik0

  I want to generate a gif from my mp4 movie with ffmpeg (ffmpeg version 2.8.15-0ubuntu0.16.04.1) using a color palette. Everything works fine if I do not use a palette :

  $ ffmpeg -i in.mp4 -filter_complex "scale=160:-1" out.gif
  
  ...
  
  frame= 2003 fps=251 q=-0.0 Lsize=   21172kB time=00:01:20.12 bitrate=2164.7kbits/s    
  
  video:21155kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.077667%

  But using a palette like so results in Buffer queue overflow, dropping messages and a truncated video

  $ ffmpeg -i in.mp4 -filter_complex "[0:v] scale=160:-1, split [a][b];[a] palettegen [p];[b][p] paletteuse" out.gif
  
  ....
  
  [Parsed_paletteuse_3 @ 0xc56de0] [framesync @ 0xd1af08] Buffer queue overflow, dropping.
  
  Last message repeated 36 times
  
  [Parsed_paletteuse_3 @ 0xc56de0] [framesync @ 0xd1af08] Buffer queue overflow, dropping.
  
  Last message repeated 106 times
  
  ...
  
  [Parsed_palettegen_2 @ 0xc56d40] 255(+1) colors generated out of 1347441 colors; ratio=0.000189
  
  frame=   65 fps=5.4 q=-0.0 Lsize=    1036kB time=00:01:20.12 bitrate= 105.9kbits/s    
  
  video:1035kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.124664%

• Fragment shader does not show any colour when compiled with vs2013

  4 septembre 2019, par 5mayfive

  When compiled with vs2010, the fragment shader works, but when I compiled and run in vs 2013, it’s grey.

  My fragment shader converts the yuv texture into rgb

  Below is my fragment code

      const char *FProgram =
  
      "uniform sampler2D Ytex;\n"
  
      "uniform sampler2D Utex;\n"
  
      "uniform sampler2D Vtex;\n"
  
      "void main(void) {\n"
  
      "  vec4 c = vec4((texture2D(Ytex, gl_TexCoord[0]).r - 16./255.) * 1.164);\n"
  
      "  vec4 U = vec4(texture2D(Utex, gl_TexCoord[0]).r - 128./255.);\n"
  
      "  vec4 V = vec4(texture2D(Vtex, gl_TexCoord[0]).r - 128./255.);\n"
  
      "  c += V * vec4(1.596, -0.813, 0, 0);\n"
  
      "  c += U * vec4(0, -0.392, 2.017, 0);\n"
  
      "  c.a = 1.0;\n"
  
      "  gl_FragColor = c;\n"
  
      "}\n";
  
  
  
  
  
  
  
  
  
  
  
  glClearColor(0, 0, 0, 0);
  
  
  
  PHandle = glCreateProgram();
  
  FSHandle = glCreateShader(GL_FRAGMENT_SHADER);
  
  
  
  
  
  
  
  glShaderSource(FSHandle, 1, &FProgram, NULL);
  
  glCompileShader(FSHandle);
  
  
  
  glAttachShader(PHandle, FSHandle);
  
  glLinkProgram(PHandle);
  
  
  
  
  
  glUseProgram(PHandle);
  
  glDeleteProgram(PHandle);
  
  glDeleteProgram(FSHandle);

  This is my texture code, I receive linesize and yuv frame data from ffmpeg and make into texture. Everything works fine in VS 2010 computer, but when compiled and run in vs2013 computer, it is grey (black n white), no colour

      /* Select texture unit 1 as the active unit and bind the U texture. */
  
  glPixelStorei(GL_UNPACK_ROW_LENGTH, linesize1);
  
  glActiveTexture(GL_TEXTURE1);
  
  i = glGetUniformLocation(PHandle, "Utex");
  
  glUniform1i(i, 1);  /* Bind Utex to texture unit 1 */
  
  glBindTexture(GL_TEXTURE_2D, 1);
  
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
  
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
  
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
  
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
  
  glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, width / 2, height / 2, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, frame1);
  
  glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
  
  
  
  
  
  /* Select texture unit 2 as the active unit and bind the V texture. */
  
  glPixelStorei(GL_UNPACK_ROW_LENGTH, linesize2);
  
  glActiveTexture(GL_TEXTURE2);
  
  i = glGetUniformLocation(PHandle, "Vtex");
  
  glUniform1i(i, 2);  /* Bind Vtext to texture unit 2 */
  
  glBindTexture(GL_TEXTURE_2D, 2);
  
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
  
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
  
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
  
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
  
  glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, width / 2, height / 2, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, frame2);
  
  glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
  
  
  
  
  
  /* Select texture unit 0 as the active unit and bind the Y texture. */
  
  
  
  
  
  
  
  glPixelStorei(GL_UNPACK_ROW_LENGTH, linesize0);
  
  glActiveTexture(GL_TEXTURE0);
  
  i = glGetUniformLocation(PHandle, "Ytex");
  
  glUniform1i(i, 0);
  
  glBindTexture(GL_TEXTURE_2D, 0);
  
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
  
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
  
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
  
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
  
  glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, width, height, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, frame0);
  
  glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
  
  
  
  
  
  
  
  glClear(GL_COLOR_BUFFER_BIT);
  
  
  
  /* Draw image (again and again). */
  
  
  
  glBegin(GL_QUADS);
  
  glTexCoord2i(0, 0);
  
  glVertex2i(-w / 2, h / 2);
  
  glTexCoord2i(1, 0);
  
  glVertex2i(w / 2, h / 2);
  
  glTexCoord2i(1, 1);
  
  glVertex2i(w / 2, -h / 2);
  
  glTexCoord2i(0, 1);
  
  glVertex2i(-w / 2, -h / 2);
  
  glEnd();

• 10bit DPX to DNXHR_444 with FFmpeg causing colour shift

  15 août 2019, par Josh Northeast

  I’m trying to build a python application to convert a 10bit DPX sequence to a 4k DNXHR_444 MOV with a Arri to Rec709 lut, just as I would in Davcincci resolve.

  ffmpeg -f image2 -framerate 24 -pattern_type glob -i INPUT.dpx -c:v dnxhd -profile:v dnxhr_444 -vf lut3d=ArriAlexa_LogCtoRec709_Resolve.cube,colormatrix=bt601:bt709 -pix_fmt yuv444p10le -c:a pcm_s16le -y -timecode 00:00:41:16 OUTPUT.mov

  When comparing the output to the dpx in resolve with the lut on it, there is a slight colour shift making everything slightly more red. Even when i take the lut out of the ffmpeg code, there is still a slight redness. The colourmatrix helps a bit to get it closer but it isn’t close enough. Any ideas why I can’t get them to match ?

  LOG :

  ffmpeg -f image2 -framerate 24 -pattern_type glob -i /dpx/*.dpx -c:v dnxhd -profile:v dnxhr_444 -vf lut3d=/Arri/ArriAlexa_LogCtoRec709_Resolve.cube,colormatrix=bt601:bt709 -pix_fmt yuv444p10le -c:a pcm_s16le -y -timecode 00:00:41:16 /dpx/test.mov
  
  ffmpeg version 4.2-static https://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2019 the FFmpeg developers
  
    built with gcc 6.3.0 (Debian 6.3.0-18+deb9u1) 20170516
  
    configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc-6 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gmp --enable-libgme --enable-gray --enable-libaom --enable-libfribidi --enable-libass --enable-libvmaf --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libdav1d --enable-libxvid --enable-libzvbi --enable-libzimg
  
    libavutil      56. 31.100 / 56. 31.100
  
    libavcodec     58. 54.100 / 58. 54.100
  
    libavformat    58. 29.100 / 58. 29.100
  
    libavdevice    58.  8.100 / 58.  8.100
  
    libavfilter     7. 57.100 /  7. 57.100
  
    libswscale      5.  5.100 /  5.  5.100
  
    libswresample   3.  5.100 /  3.  5.100
  
    libpostproc    55.  5.100 / 55.  5.100
  
  Input #0, image2, from '/dpx/*.dpx':
  
    Duration: 00:00:07.67, start: 0.000000, bitrate: N/A
  
      Stream #0:0: Video: dpx, gbrp10le, 4096x1716 [SAR 1:1 DAR 1024:429], 24 tbr, 24 tbn, 24 tbc
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (dpx (native) -> dnxhd (native))
  
  Press [q] to stop, [?] for help
  
  Output #0, mov, to '/dpx/test.mov':
  
    Metadata:
  
      timecode        : 00:00:41:16
  
      encoder         : Lavf58.29.100
  
      Stream #0:0: Video: dnxhd (DNXHR 444) (AVdh / 0x68645641), yuv444p10le, 4096x1716 [SAR 1:1 DAR 1024:429], q=2-1024, 200 kb/s, 0.04 fps, 12288 tbn, 24 tbc
  
      Metadata:
  
        encoder         : Lavc58.54.100 dnxhd
  
  frame=  184 fps=1.9 q=1.0 Lsize= 1117250kB time=00:00:07.62 bitrate=1200316.8kbits/s speed=0.0799x       
  
  video:1117248kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.000187%

  Here is a :

  • JPG - reference of what the DPX + LUT should look like
  • DPX - a frame of the dpx sequence I’m trying to convert to DNXHR_444
  • the ArriLogC_to_Rec709 LUT to be applied to the DPX
    Let me know if you need anything else.

  https://drive.google.com/drive/folders/1j2Qq1sV5ZJJsMYe3DOFOV0dnQ3VIotcw

  Cheers,
  Josh