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• How extract JPEG image from H264 stream in constant time

  27 août 2021, par Ross Gardiner

  I want to extract a JPEG frame from a H264 stream on disk. The extraction needs to be as fast as possible for my real-time requirements.

  


  Until now I have been using ffmpeg-python lib which is just a python wrapper for ffmpeg. Here is a code snippet :

  


  out, _ = (
    ffmpeg
    .input('./5sec.h264')
    .filter('select', 'gte(n,{})'.format(144))
    .output('pipe:', vframes=1, format='image2', vcodec='h264')
    .run(capture_stdout=True)
)


  


  This outputs the jpeg to stdout, with some effort I could read this into my program.

  


  However, as I use larger and larger stream files the extraction time to grab the JPEG increases. I thought lookup time would be constant as ffmpeg is highly optimised ?

  


  Is there a constant time solution to lookup and return a frame from a h264 (or even mjpeg) format stream on disk ?

  


  Edit :
Heres the command I use without the python wrapper :
ffmpeg -i 5sec.h264 -frames:v 1 -filter:v "select=gte(n\,25)" -f image2 frame.jpg

  


  here's output :

  


  ffmpeg version 4.1.6-1~deb10u1+rpt2 Copyright (c) 2000-2020 the FFmpeg developers
  built with gcc 8 (Raspbian 8.3.0-6+rpi1)
  configuration: --prefix=/usr --extra-version='1~deb10u1+rpt2' --toolchain=hardened --incdir=/usr/include/arm-linux-gnueabihf --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-omx-rpi --enable-mmal --enable-neon --enable-rpi --enable-vout-drm --enable-v4l2-request --enable-libudev --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared --libdir=/usr/lib/arm-linux-gnueabihf --cpu=arm1176jzf-s --arch=arm
  libavutil      56. 22.100 / 56. 22.100
  libavcodec     58. 35.100 / 58. 35.100
  libavformat    58. 20.100 / 58. 20.100
  libavdevice    58.  5.100 / 58.  5.100
  libavfilter     7. 40.101 /  7. 40.101
  libavresample   4.  0.  0 /  4.  0.  0
  libswscale      5.  3.100 /  5.  3.100
  libswresample   3.  3.100 /  3.  3.100
  libpostproc    55.  3.100 / 55.  3.100
Input #0, h264, from '5sec.h264':
  Duration: N/A, bitrate: N/A
    Stream #0:0: Video: h264 (High), yuv420p(progressive), 640x480, 25 fps, 25 tbr, 1200k tbn, 50 tbc
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> mjpeg (native))
Press [q] to stop, [?] for help
[swscaler @ 0x1a25390] deprecated pixel format used, make sure you did set range correctly
Output #0, image2, to 'frame.jpg':
  Metadata:
    encoder         : Lavf58.20.100
    Stream #0:0: Video: mjpeg, yuvj420p(pc), 640x480, q=2-31, 200 kb/s, 25 fps, 25 tbn, 25 tbc
    Metadata:
      encoder         : Lavc58.35.100 mjpeg
    Side data:
      cpb: bitrate max/min/avg: 0/0/200000 buffer size: 0 vbv_delay: -1
frame=    1 fps=0.4 q=6.8 Lsize=N/A time=00:00:01.04 bitrate=N/A speed=0.467x    
video:63kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown


  


  Note, achieved FPS is 0.4. When I increase the requested frame to be the 125th frame rather than the 25th, the FPS goes down to 0.1.

  


• Requirements for using ffmpeg to create mpeg4 files in SaaS solution

  25 août 2016, par Paul Fleming

  My requirement is :
   On upload of a supported video file, convert the file to common formats to maximize web compatibility.

  Essentially, I want to take a non-web-supported video file, and converted it to WEBM and MPEG4. This will take place on a Windows Server VM inside Microsoft Azure.

  ffmpeg seems to be the de facto standard for video conversion yet it introduces licensing hell, not only with GPL/LGPL but by not offering a commercial license, meaning I now have to worry about paying royalties to MPEG-LA.

  Can anyone advise on MPEG-LAs licensing model as it applies to SaaS ? I will not be distributing ffmpeg (runs server side) and the conversion takes place on Windows (Server) OS.

• alternative to FFmpeg to overlay multiple mp3 audio file over video with sound (audio) in android [closed]

  22 septembre 2021, par 1234567

  IS there an alternative to FFmpeg to overlay multiple mp3 audio file over video with sound (audio) in android

  


  Ffmpeg has GPL and LGPL License issues

  


  Media muxer is useful however it may only replace the audio or add new audio over video without sound.(Is it possible to use mediamuxer to overlay audio)

  


  Or s there any alternative available.