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• Video cropping with FFMpeg on Android is very slow [duplicate]

  7 avril 2017, par Rami Jemli

  This question already has an answer here :

  • Fast Video Compression on Android
    
    2 answers
    

  What i tried :

  I am trying to implement video cropping on android using FFMpeg (ffmpeg-android).
  

  Here is the command I use :
  

  String[] complexCommand = {"-i", inputPath, "-strict", "experimental", "-vf", "crop=1080:1080:0:0", "-threads", "5", "-c:v", "libx264", "-preset", "ultrafast", filePath};

  The problem :

  Video cropping is working, but even though I am using all needed options to make the operation fast, it still takes a 1min long video the same duration to crop.
  

  How can I achieve better speeds ?
  Will I need to implement video cropping on server instead of device ?
  Is there another way to implement video cropping on Android instead of FFMpeg ?

  I understand that I can achieve better UX by letting the user edit a cropped TextureView/SurfaceView while doing the actual cropping in background, but I want to avoid this way as it takes more time.

  UPDATE

  Here is FFMpeg’s log output :

  SUCCESS with output : ffmpeg version n3.0.1 Copyright (c) 2000-2016 the FFmpeg developers
  
      built with gcc 4.8 (GCC)
  
      configuration: --target-os=linux --cross-prefix=/home/vagrant/SourceCode/ffmpeg-android/toolchain-android/bin/arm-linux-androideabi- --arch=arm --cpu=cortex-a8 --enable-runtime-cpudetect --sysroot=/home/vagrant/SourceCode/ffmpeg-android/toolchain-android/sysroot --enable-pic --enable-libx264 --enable-libass --enable-libfreetype --enable-libfribidi --enable-libmp3lame --enable-fontconfig --enable-pthreads --disable-debug --disable-ffserver --enable-version3 --enable-hardcoded-tables --disable-ffplay --disable-ffprobe --enable-gpl --enable-yasm --disable-doc --disable-shared --enable-static --pkg-config=/home/vagrant/SourceCode/ffmpeg-android/ffmpeg-pkg-config --prefix=/home/vagrant/SourceCode/ffmpeg-android/build/armeabi-v7a --extra-cflags='-I/home/vagrant/SourceCode/ffmpeg-android/toolchain-android/include -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -fno-strict-overflow -fstack-protector-all' --extra-ldflags='-L/home/vagrant/SourceCode/ffmpeg-android/toolchain-android/lib -Wl,-z,relro -Wl,-z,now -pie' --extra-libs='-lpng -lexpat -lm' --extra-cxxflags=
  
      libavutil      55. 17.103 / 55. 17.103
  
      libavcodec     57. 24.102 / 57. 24.102
  
      libavformat    57. 25.100 / 57. 25.100
  
      libavdevice    57.  0.101 / 57.  0.101
  
      libavfilter     6. 31.100 /  6. 31.100
  
      libswscale      4.  0.100 /  4.  0.100
  
      libswresample   2.  0.101 /  2.  0.101
  
      libpostproc    54.  0.100 / 54.  0.100
  
      Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/storage/emulated/0/DCIM/100ANDRO/MOV_0066.mp4':
  
      Metadata:
  
      major_brand     : mp42
  
      minor_version   : 0
  
      compatible_brands: isommp42
  
      creation_time   : 2017-04-02 11:58:58
  
      com.android.version: 6.0.1
  
      Duration: 00:00:59.60, start: 0.000000, bitrate: 17759 kb/s
  
      Stream #0:0(eng): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080, 17498 kb/s, SAR 1:1 DAR 16:9, 29.90 fps, 29.92 tbr, 90k tbn, 180k tbc (default)
  
      Metadata:
  
      rotate          : 90
  
      creation_time   : 2017-04-02 11:58:58
  
      handler_name    : VideoHandle
  
      Side data:
  
      displaymatrix: rotation of -90.00 degrees
  
      Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 155 kb/s (default)
  
      Metadata:
  
      creation_time   : 2017-04-02 11:58:58
  
      handler_name    : SoundHandle
  
      [libx264 @ 0xb5bc4400] using SAR=1/1
  
      [libx264 @ 0xb5bc4400] using cpu capabilities: none!
  
      [libx264 @ 0xb5bc4400] profile High 4:4:4 Predictive, level 3.2, 4:2:0 8-bit
  
      [libx264 @ 0xb5bc4400] 64 - core 148 - H.264/MPEG-4 AVC codec - Copyleft 2003-2015 - http://www.videolan.org/x264.html - options: cabac=1 ref=1 deblock=1:0:0 analyse=0x1:0x1 me=dia subme=1 psy=0 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=0 chroma_qp_offset=0 threads=5 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=1 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc=cqp mbtree=0 qp=0
  
      Output #0, mp4, to '/storage/emulated/0/Download/compress_video1.mp4':
  
      Metadata:
  
      major_brand     : mp42
  
      minor_version   : 0
  
      compatible_brands: isommp42
  
      com.android.version: 6.0.1
  
      encoder         : Lavf57.25.100
  
      Stream #0:0(eng): Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 1080x1080 [SAR 1:1 DAR 1:1], q=-1--1, 29.92 fps, 11488 tbn, 29.92 tbc (default)
  
      Metadata:
  
      handler_name    : VideoHandle
  
      creation_time   : 2017-04-02 11:58:58
  
      encoder         : Lavc57.24.102 libx264
  
      Side data:
  
      unknown side data type 10 (24 bytes)
  
      Stream #0:1(eng): Audio: aac (LC) ([64][0][0][0] / 0x0040), 48000 Hz, stereo, fltp, 128 kb/s (default)
  
      Metadata:
  
      creation_time   : 2017-04-02 11:58:58
  
      handler_name    : SoundHandle
  
      encoder         : Lavc57.24.102 aac
  
      Stream mapping:
  
      Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
  
      Stream #0:1 -> #0:1 (aac (native) -> aac (native))
  
      Press [q] to stop, [?] for help
  
      frame=    6 fps=0.0 q

  Any help is greatly appreciated !

• Conditional expressions not working in ffmpeg ?

  8 avril 2017, par Don Clifton

  I’m having trouble with conditional expressions generating errors in ffmpeg. Here is an example of the problem, which is taken from the ffmpeg documentation for the blend filter :

  ffmpeg -i lyt1s.mp4 -i lyt1r.mp4 -filter_complex \
  
      'blend=all_expr=if(eq(mod(X,2),mod(Y,2)),A,B)' lytx.mp

  The following output is generated :

  ffmpeg version 3.2.4 Copyright (c) 2000-2017 the FFmpeg developers
  
  built with llvm-gcc 4.2.1 (LLVM build 2336.11.00)
  
  configuration: --prefix=/Volumes/Ramdisk/sw --enable-gpl --enable-pthreads         --enable-version3 --enable-libspeex --enable-libvpx --disable-decoder=libvpx --enable-libmp3lame --enable-libtheora --enable-libvorbis --enable-libx264 --enable-avfilter --enable-libopencore_amrwb --enable-libopencore_amrnb --enable-filters --enable-libgsm --enable-libvidstab --enable-libx265 --disable-doc --arch=x86_64 --enable-runtime-cpudetect``
  
    libavutil      55. 34.101 / 55. 34.101
  
    libavcodec     57. 64.101 / 57. 64.101
  
    libavformat    57. 56.101 / 57. 56.101
  
    libavdevice    57.  1.100 / 57.  1.100
  
    libavfilter     6. 65.100 /  6. 65.100
  
    libswscale      4.  2.100 /  4.  2.100
  
    libswresample   2.  3.100 /  2.  3.100
  
    libpostproc    54.  1.100 / 54.  1.100
  
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'lyt1s.mp4':
  
    Metadata:
  
      major_brand     : isom
  
      minor_version   : 512
  
      compatible_brands: isomiso2avc1mp41
  
      encoder         : Lavf57.56.101
  
    Duration: 00:00:40.04, start: 0.000000, bitrate: 4337 kb/s
  
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 4202 kb/s, 25 fps, 25 tbr, 12800 tbn, 50 tbc (default)
  
      Metadata:
  
        handler_name    : VideoHandler
  
      Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
  
      Metadata:
  
        handler_name    : SoundHandler
  
  Input #1, mov,mp4,m4a,3gp,3g2,mj2, from 'lyt1r.mp4':
  
    Metadata:
  
      major_brand     : isom
  
      minor_version   : 512
  
      compatible_brands: isomiso2avc1mp41
  
      encoder         : Lavf57.56.101
  
    Duration: 00:00:40.04, start: 0.000000, bitrate: 2410 kb/s
  
      Stream #1:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 2275 kb/s, 25 fps, 25 tbr, 12800 tbn, 50 tbc (default)
  
      Metadata:
  
        handler_name    : VideoHandler
  
      Stream #1:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
  
      Metadata:
  
    handler_name    : SoundHandler
  
  [AVFilterGraph @ 0x7fc7f1d0a6a0] No such filter: '2)'
  
  Error initializing complex filters.
  
  Invalid argument

  If I replace the all_expr argument to something that doesn’t include a conditional expression (such as A*0.5+B*0.5) the blend filter does what it’s supposed to, without any errors.

  Can anyone tell me what’s going on here ?

• FFmpeg - selecting appropriate bitrate for VP9 encoding

  6 avril 2017, par fastily

  I am looking to encode a 4k video shot with iPhone 6s in VP9 in the best quality possible.

  For reference, stream data of the video I would like to encode, via ffprobe :

  Duration: 00:00:10.48, start: 0.000000, bitrate: 46047 kb/s
  
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv, bt709), 3840x2160, 45959 kb/s, 29.98 fps, 29.97 tbr, 600 tbn, 1200 tbc (default)
  
      Metadata:
  
        creation_time   : 2017-03-13T21:12:56.000000Z
  
        handler_name    : Core Media Data Handler
  
        encoder         : H.264
  
      Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, mono, fltp, 79 kb/s (default)
  
      Metadata:
  
        creation_time   : 2017-03-13T21:12:56.000000Z
  
        handler_name    : Core Media Data Handler

  I am using the following FFmpeg commands, based on these instructions (see Best Quality (Slowest) Recommended Settings section).

  1. ffmpeg -i INPUT.mov -c:v libvpx-vp9 -pass 1 -b:v 46000K -threads 4 -speed 4 -g 9999 -an -f webm -y /dev/null
  2. ffmpeg -I INPUT.mov -c:v libvpx-vp9 -pass 2 -b:v 46000K -threads 4 -speed 0 -g 9999 -an -f webm OUTPUT.webm

  Is there a best practice to select an optimal -b:v value such that the resulting video is visually indistinguishable from the original ? I have tried values ranging from 36000K-46000K, but these result in massive files with an overall bitrate exceeding the target bitrate.

  Thanks in advance !