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• How to process video stream ?

  27 avril 2016, par sharpener

  I would like to ask some experienced multimedia professional how to proceed with following task :

  Given URL provides video stream and we would like to get access to decoded frames (byte stream in memory) in managed Win7+ application (C#). We don’t want to render/present the frames the standard way. The video format is known but not fixed (might get changed between two successive sessions, but we will know the parameters).

  So far, I have found there are several methods and I have build following picture in my mind :

  1. ffmpeg wrapper
     • Pros
       1. Self contained (no dependency to windows technologies)
       2. Powerful
     • Cons
       1. Little more complex to understand
       2. Lot of different wrapping variants (FFmpeg.NET, ffmpeg-sharp, ffmpeg-shard, FFmpeg.AutoGen, ...)
  2. DirectShow wrapper
     • Pros
       1. Widely used/supported technology (variaous filters freely available)
       2. Nice/detailed documentation on MSDN
     • Cons
       1. Quite old
       2. Considered obsolete from the point of author’s view (available only for desktop model on runtime >= Win8)
  3. MediaFoundation wrapper
     • Pros
       1. Theoretical successor of DirectShow, so should be available in the future
     • Cons
       1. Seems to be not as good as DirectShow
       2. Not very popular, limited "community" support
  4. FFmpegInterop wrapper
     • Pros
       1. Microsoft’s open source wrapper alternative
     • Cons
       1. Not available for runtime < Win8

• FFmpeg cannot extract correct first frame - always extract the second frame [closed]

  21 octobre 2024, par Cai Yu

  I am on macos Ventura 13.2.1, on Macbook Pro M1Max.

  &#xA;

  The video is number counting animation video. From 2 to 125. The number on first frame is 2. The number on last frame is 125. The number plus one on each frame. You can download the video here.

  &#xA;

  NOTE that :&#xA;First, you hit space bar to play it in Finder, you can see the first frame of the video is number 2.

  &#xA;

  Second, in professional Video editing software - davinci resolve, on the timeline, you can see the first frame is number 2.

  &#xA;

  Now I try to use FFmpeg to extract the first frame of the video.&#xA;First Try :

  &#xA;

  ffmpeg -i /Users/chris/Downloads/2to125.mov -vframes 1 /Users/chris/Downloads/1.png


  &#xA;

  The output png image is number 3. So it's actually the second frame.

  &#xA;

  Second try :

  &#xA;

  ffmpeg -i /Users/chris/Downloads/2to125.mov -frames:v 1 /Users/chris/Downloads/1.png


  &#xA;

  The output png image is still the second frame - the number 3.

  &#xA;

  Third try :

  &#xA;

  ffmpeg -i /Users/chris/Downloads/2to125.mov -vf "select=eq(n\,0)" -q:v 3 /Users/chris/Downloads/1.png


  &#xA;

  The output image is sitll the wrong second frame.

  &#xA;

  NOTE that :

  &#xA;

  first : all these three method are from internet. And a lot of people voted correct answer for this question.

  &#xA;

  second : all their output on my system is the incorrect second frame, not the first frame.

  &#xA;

  I cannot find what's wrong. Hope friend here help me.

  &#xA;

• Unable to use Makefile on ffmpegthumbnailer setup files with Cygwin for Windows 10

  21 août 2018, par Cole Phiper

  I am currently trying to build the exe/binary files to support ffmpegthumbnailer on Windows 10. I read multiple posts on getting it to work, but none seem to satisfy my needs. I currently have ffmpegthumbnailer-2.2.0 stored at C :\ffmpegthumbnailer-2.2.0 I see a folder named CMakeFiles, dist, kffmpegthumbnailer, libffmpegthumbnailer, man, test and thunar files. When I run make in the directory, I receive

  User@User-WIN10 /cygdrive/c/ffmpegthumbnailer-2.2.0/man
  
  $ make
  
  make: *** No targets specified and no makefile found.  Stop.

  How do I build/make the exec files, so that I can use the PATH variable to find ffmpegthumbnailer ?

  UPDATE 1 :
  I tried the automake command, but I received the message below

  $ automake
  
  /cygdrive/c/RubyDevKit/mingw/bin/automake: /cygdrive/c/RubyDevKit/mingw/bin/automake-1.11: /bin/perl: bad interpreter: No such file or directory
  
  /cygdrive/c/RubyDevKit/mingw/bin/automake: line 156: /cygdrive/c/RubyDevKit/mingw/bin/automake-1.11: No error

  UPDATE 2 :

  I ran cmake and received the message below.

  Coder@Coder-WIN10 /cygdrive/c/ffmpegthumbnailer-2.2.0/ffmpegthumbnailer_build
  
  $ cmake ../
  
  -- Building for: Visual Studio 15 2017
  
  -- The C compiler identification is MSVC 19.14.26428.1
  
  -- The CXX compiler identification is MSVC 19.14.26428.1
  
  -- Check for working C compiler: C:/Program Files (x86)/Microsoft Visual Studio2017/Professional/VC/Tools/MSVC/14.14.26428/bin/Hostx86/x86/cl.exe
  
  -- Check for working C compiler: C:/Program Files (x86)/Microsoft Visual Studio2017/Professional/VC/Tools/MSVC/14.14.26428/bin/Hostx86/x86/cl.exe -- works
  
  -- Detecting C compiler ABI info
  
  -- Detecting C compiler ABI info - done
  
  -- Detecting C compile features
  
  -- Detecting C compile features - done
  
  -- Check for working CXX compiler: C:/Program Files (x86)/Microsoft Visual Studo/2017/Professional/VC/Tools/MSVC/14.14.26428/bin/Hostx86/x86/cl.exe
  
  -- Check for working CXX compiler: C:/Program Files (x86)/Microsoft Visual Studo/2017/Professional/VC/Tools/MSVC/14.14.26428/bin/Hostx86/x86/cl.exe -- works
  
  -- Detecting CXX compiler ABI info
  
  -- Detecting CXX compiler ABI info - done
  
  -- Detecting CXX compile features
  
  -- Detecting CXX compile features - done
  
  -- Could NOT find JPEG (missing: JPEG_LIBRARY JPEG_INCLUDE_DIR)
  
  -- Could NOT find ZLIB (missing: ZLIB_LIBRARY ZLIB_INCLUDE_DIR)
  
  -- Could NOT find PNG (missing: PNG_LIBRARY PNG_PNG_INCLUDE_DIR)
  
  -- Could NOT find PkgConfig (missing: PKG_CONFIG_EXECUTABLE)
  
  CMake Error at C:/Program Files/CMake/share/cmake-3.12/Modules/FindPkgConfig.cmke:489 (message):
  
    pkg-config tool not found
  
  Call Stack (most recent call first):
  
    C:/Program Files/CMake/share/cmake-3.12/Modules/FindPkgConfig.cmake:602 (_pkgcheck_modules_internal)
  
    CMakeLists.txt:58 (PKG_CHECK_MODULES)
  
  
  
  
  
  CMake Error at C:/Program Files/CMake/share/cmake-3.12/Modules/FindPkgConfig.cmke:489 (message):
  
    pkg-config tool not found
  
  Call Stack (most recent call first):
  
    C:/Program Files/CMake/share/cmake-3.12/Modules/FindPkgConfig.cmake:602 (_pkgcheck_modules_internal)
  
    CMakeLists.txt:59 (PKG_CHECK_MODULES)
  
  
  
  
  
  CMake Error at C:/Program Files/CMake/share/cmake-3.12/Modules/FindPkgConfig.cmke:489 (message):
  
    pkg-config tool not found
  
  Call Stack (most recent call first):
  
    C:/Program Files/CMake/share/cmake-3.12/Modules/FindPkgConfig.cmake:602 (_pkgcheck_modules_internal)
  
    CMakeLists.txt:60 (PKG_CHECK_MODULES)
  
  
  
  
  
  CMake Error at C:/Program Files/CMake/share/cmake-3.12/Modules/FindPkgConfig.cmke:489 (message):
  
    pkg-config tool not found
  
  Call Stack (most recent call first):
  
    C:/Program Files/CMake/share/cmake-3.12/Modules/FindPkgConfig.cmake:602 (_pkgcheck_modules_internal)
  
    CMakeLists.txt:61 (PKG_CHECK_MODULES)
  
  
  
  
  
  --
  
  -- CONFIGURATION SUMMARY
  
  -- png support          : disabled
  
  -- jpeg support         : disabled
  
  -- gio support          : disabled
  
  -- register thumbnailer : disabled
  
  -- unittests            : enabled
  
  -- debug mode           : disabled
  
  CMake Error: The following variables are used in this project, but they are setto NOTFOUND.
  
  Please set them or make sure they are set and tested correctly in the CMake fils:
  
  AVCODEC_INCLUDE_DIR
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0/test
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0/test
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0/test
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0/test
  
  AVCODEC_LIBRARY
  
      linked by target "libffmpegthumbnailer" in directory C:/ffmpegthumbnailer-22.0
  
  AVFILTER_INCLUDE_DIR
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0/test
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0/test
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0/test
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0/test
  
  AVFILTER_LIBRARY
  
      linked by target "libffmpegthumbnailer" in directory C:/ffmpegthumbnailer-22.0
  
  AVFORMAT_INCLUDE_DIR
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0/test
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0/test
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0/test
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0/test
  
  AVFORMAT_LIBRARY
  
      linked by target "libffmpegthumbnailer" in directory C:/ffmpegthumbnailer-22.0
  
  AVUTIL_INCLUDE_DIR
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0/test
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0/test
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0/test
  
     used as include directory in directory C:/ffmpegthumbnailer-2.2.0/test
  
  AVUTIL_LIBRARY
  
      linked by target "libffmpegthumbnailer" in directory C:/ffmpegthumbnailer-22.0
  
  
  
  -- Configuring incomplete, errors occurred!
  
  See also "C:/ffmpegthumbnailer-2.2.0/ffmpegthumbnailer_build/CMakeFiles/CMakeOuput.log".
  
  
  
  Coder@Coder-WIN10 /cygdrive/c/ffmpegthumbnailer-2.2.0/ffmpegthumbnailer_build
  
  $

  UPDATE 3

  Coder@Coder-WIN10 ~
  
  $ cd C:\ffmpegthumbnailer-2.2.0
  
  
  
  Coder@Coder-WIN10 /cygdrive/c/ffmpegthumbnailer-2.2.0
  
  $ cd ffmpegthumbnailer_build
  
  
  
  Coder@Coder-WIN10 /cygdrive/c/ffmpegthumbnailer-2.2.0/ffmpegthumbnailer_build
  
  $ cmake ../
  
  -- The C compiler identification is GNU 7.3.0
  
  -- The CXX compiler identification is GNU 7.3.0
  
  CMake Warning at /usr/share/cmake-3.6.2/Modules/Platform/CYGWIN.cmake:15 (message):
  
    CMake no longer defines WIN32 on Cygwin!
  
  
  
    (1) If you are just trying to build this project, ignore this warning or
  
    quiet it by setting CMAKE_LEGACY_CYGWIN_WIN32=0 in your environment or in
  
    the CMake cache.  If later configuration or build errors occur then this
  
    project may have been written under the assumption that Cygwin is WIN32.
  
    In that case, set CMAKE_LEGACY_CYGWIN_WIN32=1 instead.
  
  
  
    (2) If you are developing this project, add the line
  
  
  
      set(CMAKE_LEGACY_CYGWIN_WIN32 0) # Remove when CMake >= 2.8.4 is required
  
  
  
    at the top of your top-level CMakeLists.txt file or set the minimum
  
    required version of CMake to 2.8.4 or higher.  Then teach your project to
  
    build on Cygwin without WIN32.
  
  Call Stack (most recent call first):
  
    /usr/share/cmake-3.6.2/Modules/CMakeSystemSpecificInformation.cmake:36 (include)
  
    CMakeLists.txt:26 (PROJECT)
  
  
  
  
  
  -- Check for working C compiler: /usr/bin/cc
  
  -- Check for working C compiler: /usr/bin/cc -- works
  
  -- Detecting C compiler ABI info
  
  -- Detecting C compiler ABI info - done
  
  -- Detecting C compile features
  
  -- Detecting C compile features - done
  
  -- Check for working CXX compiler: /usr/bin/c++.exe
  
  -- Check for working CXX compiler: /usr/bin/c++.exe -- works
  
  -- Detecting CXX compiler ABI info
  
  -- Detecting CXX compiler ABI info - done
  
  -- Detecting CXX compile features
  
  -- Detecting CXX compile features - done
  
  -- Found JPEG: /usr/lib/libjpeg.dll.a
  
  -- Found ZLIB: /usr/lib/libz.dll.a (found version "1.2.11")
  
  -- Found PNG: /usr/lib/libpng.dll.a (found version "1.6.34")
  
  -- Found PkgConfig: /usr/bin/pkg-config.exe (found version "0.29.1")
  
  -- Checking for module 'libavcodec'
  
  --   No package 'libavcodec' found
  
  CMake Error at /usr/share/cmake-3.6.2/Modules/FindPkgConfig.cmake:424 (message):
  
    A required package was not found
  
  Call Stack (most recent call first):
  
    /usr/share/cmake-3.6.2/Modules/FindPkgConfig.cmake:597 (_pkg_check_modules_internal)
  
    CMakeLists.txt:58 (PKG_CHECK_MODULES)
  
  
  
  
  
  -- Configuring incomplete, errors occurred!
  
  See also "/cygdrive/c/ffmpegthumbnailer-2.2.0/ffmpegthumbnailer_build/CMakeFiles/CMakeOutput.log".
  
  
  
  Coder@Coder-WIN10 /cygdrive/c/ffmpegthumbnailer-2.2.0/ffmpegthumbnailer_build
  
  $