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• Ffmpeg Symfony5 PHP8 [duplicate]

  11 septembre 2021, par Kévin Ducrocq

  I'm a french student learning web development, and how to create websites on Symfony 5.

  


  I've got this project to create a kind of Youtube website using Ffmpeg to convert and treat videos.

  


  However, when I try to use the "composer require php-ffmpeg/php-ffmpeg" command, it doesn't work and I really don't know what to do.

  


  here's the error I've got :

  


  PS C :\Users\Dev\Documents\Dev\Symfony\Youride> composer require php-ffmpeg/php-ffmpeg
Using version ^0.18.0 for php-ffmpeg/php-ffmpeg
./composer.json has been updated
Running composer update php-ffmpeg/php-ffmpeg
Loading composer repositories with package information
Updating dependencies
Your requirements could not be resolved to an installable set of packages.

  


  Problem 1
- Root composer.json requires php-ffmpeg/php-ffmpeg ^0.18.0 -> satisfiable by php-ffmpeg/php-ffmpeg[v0.18.0].
- php-ffmpeg/php-ffmpeg v0.18.0 requires doctrine/cache ^1.0 -> found doctrine/cache[v1.0, ..., 1.12.1] but it conflicts with your root composer.json require (^2.1).

  


  Use the option —with-all-dependencies (-W) to allow upgrades, downgrades and removals for packages currently locked to specific versions.

  


  Installation failed, reverting ./composer.json and ./composer.lock to their original content.
PS C :\Users\Dev\Documents\Dev\Symfony\Youride>

  


  thank you for your help, I'm a beginner... :)

  


• 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.

  


• avcodec/hevcdec : apply H.274 film grain

  29 septembre 2021, par Niklas Haas

  avcodec/hevcdec : apply H.274 film grain
  Similar in spirit and design to 66845cffc3bbb, but slightly simpler due
  
  to the lack of interlaced frames in HEVC. See that commit for more
  
  details.
  For the seed value, since no specification for this appears to exist, I
  
  semi-arbitrarily decided to base it off the POC id alone, since there's
  
  no analog of the idr_pic_id in HEVC's I-frames. This design is stable
  
  across remuxes and seeks, but changes for adjacent frames with a period
  
  that's typically long enough not to be noticeable, which makes it
  
  satisfy all of the requirements that a film grain seed should have.
  Tested with and without threading, using a patch to insert film grain
  
  metadata artificially (for lack of real files containing film grain).
  

  • [DH] libavcodec/hevc_refs.c
  • [DH] libavcodec/hevcdec.c
  • [DH] libavcodec/hevcdec.h