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• fftools/ffmpeg : add thread-aware transcode scheduling infrastructure

  18 mai 2023, par Anton Khirnov

  fftools/ffmpeg : add thread-aware transcode scheduling infrastructure
  See the comment block at the top of fftools/ffmpeg_sched.h for more
  
  details on what this scheduler is for.
  This commit adds the scheduling code itself, along with minimal
  
  integration with the rest of the program :
  
  * allocating and freeing the scheduler
  
  * passing it throughout the call stack in order to register the
  
    individual components (demuxers/decoders/filtergraphs/encoders/muxers)
  
    with the scheduler
  The scheduler is not actually used as of this commit, so it should not
  
  result in any change in behavior. That will change in future commits.
  

  • [DH] fftools/Makefile
  • [DH] fftools/ffmpeg.c
  • [DH] fftools/ffmpeg.h
  • [DH] fftools/ffmpeg_dec.c
  • [DH] fftools/ffmpeg_demux.c
  • [DH] fftools/ffmpeg_enc.c
  • [DH] fftools/ffmpeg_filter.c
  • [DH] fftools/ffmpeg_mux.c
  • [DH] fftools/ffmpeg_mux.h
  • [DH] fftools/ffmpeg_mux_init.c
  • [DH] fftools/ffmpeg_opt.c
  • [DH] fftools/ffmpeg_sched.c
  • [DH] fftools/ffmpeg_sched.h

• OpenCV VideoWriter will not open

  21 février 2015, par ChrisC

  I’m having trouble instantiating and opening an OpenCV VideoWriter for recording video on a Raspberry Pi (Raspbian Weezy).

  My project is written in C++, but I’ve written a minimal Python program that demonstrates the problem.

  https://gist.github.com/chriscollins/11ff2f43852e1c93dae8

  Both my C++ code and the Python code above run without problem on my Windows machine. Sometimes the writer does not open, but that’s to be expected - I don’t have all of the listed codecs installed (the list of codecs comes from the Open CV source), but a good number of them work correctly. However, on a Raspberry Pi, both the C++ code and the Python code fail with the VideoWriter never being opened. In the above Python code, writer.isOpened() returns false for every single codec, when run on a Raspberry Pi.

  I’ve chowned the destination directory to the user I’m running the Python script as, and chmodded it to 777 so I don’t believe that it is a permissions problem. I think it may be connected with how I’ve installed OpenCV or some of its dependencies, but I’m not sure how to rectify it.

  The install process I’ve used is as follows :

  1. Update firmware/packages via rpi-update, apt-get update and apt-get upgrade.

  2. Install the following dependencies via apt-get :

     libjpeg8
libjpeg8-dev
libjpeg8-dbg
libjpeg-progs
ffmpeg
libavcodec-dev
libavcodec53
libavformat53
libavformat-dev
libgstreamer0.10-0-dbg
libgstreamer0.10-0
libgstreamer0.10-dev
libxine1-ffmpeg
libxine-dev
libxine1-bin
libunicap2
libunicap2-dev
swig
libv4l-0
libv4l-dev
python-numpy
libpython2.6
python-dev
python2.6-dev
libgtk2.0-dev

  3. Download and unzip http://sourceforge.net/projects/opencvlibrary/files/opencv-unix/2.4.9/opencv-2.4.9.zip to /root/opencv-2.4.9.

  4. cd /root/opencv-2.4.9 and run cmake -DCMAKE_BUILD_TYPE=RELEASE -DCMAKE_INSTALL_PREFIX=/usr/local -DBUILD_PERF_TESTS=OFF -DBUILD_opencv_gpu=OFF -DBUILD_opencv_ocl=OFF. Output of cmake is available at https://gist.github.com/chriscollins/d8060e03a6acd6d4336c

  5. make and make install from the same directory.

  Various other OpenCV functionality works correctly on the Raspberry Pi (in C++ or in Python) - e.g. viewing a webcam via VideoCapture, but I can’t get the VideoWriter to work. I’m tempted to try installing FFMPEG from source instead of via apt-get, but as make takes 5+ hours to run on a Raspberry Pi, I was hoping I’d find the answer here, rather than proceeding with a trial and error approach !

  Any advice on how to solve (or debug) this is appreciated.

  EDIT : Added output of cmake command (https://gist.github.com/chriscollins/d8060e03a6acd6d4336c)

• How to embed an MP4 inside a PDF ?

  19 août 2020, par malat

  I am a happy user of img2pdf. This tool does the minimal amount of work to put a series of JPEG 2000/JPEG/PNG images into a PDF "enveloppe". However I am now faced with a new challenge : embed a MP4 file into a PDF "enveloppe".

  


  I see that commercial tool can do it, as seen at :

  


  

  • Add audio, video, and interactive objects to PDFs

  


  


  Here is one such sample PDF file (no Flash required on windows in this sample) :

  


  

  • https://gitlab.com/agrahn/media9/-/issues/9#note_345903962
** https://gitlab.com/agrahn/media9/uploads/90fddd777e0ec514c39c924cd8d3b688/video_test.pdf

  


  


  It seems to have been introduced in ISO 32000-1 (PDF 1.7 Extension Level 5)

  


  I am looking for a solution which will use the Rich Media annotation inside the PDF stream.

  


  There are dozen of duplicated questions on superuser/stackoverflow, which all pretty much refer to imagemagick/convert command line tool. But in my case, convert expand the images into a multi-page PDF (which is not my desired behavior) :

  


  $ convert input.mp4 output.pdf
$ pdfinfo output.pdf 
Title:          out
Producer:       https://imagemagick.org
CreationDate:   Wed Aug 19 15:38:01 2020 CEST
ModDate:        Wed Aug 19 15:38:01 2020 CEST
Tagged:         no
UserProperties: no
Suspects:       no
Form:           none
JavaScript:     no
Pages:          1601
Encrypted:      no
Page size:      352 x 288 pts
Page rot:       0
File size:      534407296 bytes
Optimized:      no
PDF version:    1.3


  


  with :

  


  $ convert --version
Version: ImageMagick 6.9.10-23 Q16 x86_64 20190101 https://imagemagick.org
Copyright: © 1999-2019 ImageMagick Studio LLC
License: https://imagemagick.org/script/license.php
Features: Cipher DPC Modules OpenMP 
Delegates (built-in): bzlib djvu fftw fontconfig freetype jbig jng jpeg lcms lqr ltdl lzma openexr pangocairo png tiff webp wmf x xml zlib


  


  and

  


  $ file input.mp4 
input.mp4: ISO Media, MP4 Base Media v1 [IS0 14496-12:2003]
$ ffprobe -v quiet -print_format json  -show_streams input.mp4 | grep codec_long_name
            "codec_long_name": "H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10",