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• sws_scale screws up last pixel row in smaller x264 mp4 encoding

  23 juillet 2012, par TheSHEEEP

  I am muxing pictures in the PIX_FMT_ARGB format into an mp4 video.

  All of it works well, except that the last pixel row of the outgoing image is screwed up, in most cases the last row is completely black, sometimes there are other colors, it seems somehow dependant on the machine it runs on.

  I am absolutely sure that the error must be in sws_scale, as I am saving the images before and after the scaling. The input images do not have the error, but after the sws_scale() I save the yuv image and the error is apparent.

  Here is an example :

  Original

  

  Yuvfile (after sws_scale)

  

  At the bottom of the Yuvfile, you will see the black row.

  This is how I do the scaling (it is after the official ffmpeg examples, more or less) :

  static int sws_flags = SWS_FAST_BILINEAR | SWS_ACCURATE_RND;
  
  
  
  if (img_convert_ctx == NULL)
  
  {
  
     img_convert_ctx = sws_getContext( srcWidth, srcHeight,
  
             PIX_FMT_ARGB,
  
             codecContext->width, codecContext->height,
  
             codecContext->pix_fmt,
  
             sws_flags, NULL, NULL, NULL );
  
     if (img_convert_ctx == NULL)
  
     {
  
        av_log(c, AV_LOG_ERROR, "%s","Cannot initialize the conversion context\n");
  
        exit(1);
  
     }
  
  }
  
  fill_image(tmp_picture, pic, pic_size, frame_count, ptr->srcWidth, ptr->srcHeight );
  
  
  
  sws_scale(img_convert_ctx, tmp_picture->data, tmp_picture->linesize,
  
          0, srcHeight, picture->data, picture->linesize);

  I also tried a number of different SWS_ flags, but all yield the same result.

  Could this be a bug in sws_scale or am I doing something wrong ? I am using the latest version of the ffmpeg libraries.

• Why does Apple support H.265 playback, but not when using HLS ? [closed]

  13 mars, par clark wu

  Apple devices (iPhone, iPad, macOS Safari) can natively play H.265 (HEVC) videos in .mp4 or .mov format. However, when I try to convert the same video to HLS, it fails to play. Here’s what I tested :

  


  Test Cases

  


  ✅ Directly playing H.265 .mp4 → Works fine

  


  ❌ H.265 + Opus → HLS (fMP4) → Fails

  


  ❌ H.265 + AAC → HLS (TS) → Fails

  


  ✅ H.264 + Opus → HLS fMP4 → Works fine (video + audio)

  


  ✅ H.264 + Opus → HLS TS → Video plays, but no audio

  


  ❌ H.265 + AAC → HLS fMP4 → Doesn’t play at all

  


  FFmpeg Commands Used

  


  1️⃣ H.265 + Opus (fMP4 segments)

  


  ffmpeg -i input.mp4 -c:v copy -c:a copy -hls_segment_type fmp4 -hls_time 10 -hls_list_size 0 -hls_flags independent_segments output.m3u8


  


  2️⃣ H.265 + AAC (TS segments)

  


  ffmpeg -i input.mp4 -c:v copy -c:a copy -hls_time 10 -hls_list_size 0 -hls_flags independent_segments output.m3u8


  


  Playback Attempts

  


  Vidstack.js player (Fails)

  


  Several online M3U8 players (All fail)

  


  Key Questions

  


  Why does Apple support H.265 in MP4 but not in HLS ?

  


  Is this an HLS specification limitation ?

  


  Does the audio codec (Opus / AAC) affect playback ?

  


  Does HLS require a specific HEVC profile/level ?

  


  Is HLS only compatible with AVC, not HEVC ?

  


  Looking for Answers

  


  Has anyone successfully played H.265 + HLS on Apple devices ?

  


  Are there any official Apple HLS specifications regarding HEVC support ?

  


  Possible workarounds or alternative solutions ?

  


  Would appreciate any insights or help from the community ! Thanks !

  


• ffmpeg - Unrecognized option lavfi_complex

  4 février 2019, par Milan

  I’m working with headphone filter command from official documentation - https://ffmpeg.org/ffmpeg-filters.html#Examples-20

  ffmpeg -i input.wav -lavfi-complex "amovie=azi_270_ele_0_DFC.wav[sr],amovie=azi_90_ele_0_DFC.wav[sl],amovie=azi_225_ele_0_DFC.wav[br],amovie=azi_135_ele_0_DFC.wav[bl],amovie=azi_0_ele_0_DFC.wav,asplit[fc][lfe],amovie=azi_35_ele_0_DFC.wav[fl],amovie=azi_325_ele_0_DFC.wav[fr],[a:0][fl][fr][fc][lfe][bl][br][sl][sr]headphone=FL|FR|FC|LFE|BL|BR|SL|SR"
  
  output.wav

  but I’m getting error

   Unrecognized option 'lavfi-complex'.

  Here is my ffmpeg version info -

  ffmpeg -version
  
  ffmpeg version N-92377-g0c6d4e7ba4 Copyright (c) 2000-2018 the FFmpeg developers
  
  built with gcc 8.2.1 (GCC) 20181017
  
  configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth
  
  libavutil      56. 23.101 / 56. 23.101
  
  libavcodec     58. 39.100 / 58. 39.100
  
  libavformat    58. 22.100 / 58. 22.100
  
  libavdevice    58.  6.100 / 58.  6.100
  
  libavfilter     7. 43.100 /  7. 43.100
  
  libswscale      5.  4.100 /  5.  4.100
  
  libswresample   3.  4.100 /  3.  4.100
  
  libpostproc    55.  4.100 / 55.  4.100