Recherche avancée

Sur d’autres sites (10450)

• Aforge FFMpeg DLL Location Issue

  4 novembre 2013, par Sam35

  I'm using AForge FFMPEG libraries for video compression in .Net.Currently I've put the ffmpeg & Aforge libraries in the location which the application(.exe) exists.

  I need to put these libraries in a common place.i've tried to put these libraries inside system32 folder. It is not working.

  Is there any ways to put the Aforge & FFMpeg Libraries in a common place other than application(.exe) directory ?

• ffmpeg : Failed to call av_register_all

  19 décembre 2013, par oferbar

  I've got an Windows 7 application that is using ffmpeg to decode video frames.

  It is using an older version of ffmpeg (not sure exactly which one) but it is working ok, except some decoding errors when calling avcodec_decode_video2 from increasing number of threads.

  So I decided to upgrade the ffmpeg to a newer build and got 2.1.1 (latest).
  I got it off http://ffmpeg.zeranoe.com/builds/

  I managed to compile the application using the new include/libs.

  However, when I run the application it throws an exception that a function was not found during dll loading.
  I traced that to av_register_all() which is inside avformat.lib and avformat-55.dll.

  It looks like the definition of this function in tha ffmpeg library was changed over the versions. It no longer points to avformat-55.dll (none that I was able to find using dumpbin).

  So what is the best way to call this function from a C++ dll ?

  Currently, in my include file I have this :

  extern "C" 
  
  {
  
  #include "libavutil\dict.h"
  
  #include "libavcodec\avcodec.h"
  
  #include "libavformat\avformat.h"
  
  
  
  };
  
  
  
  #pragma comment(lib,"avcodec.lib")
  
  #pragma comment(lib,"avformat.lib")
  
  #pragma comment(lib,"avutil.lib")

  Many thanks !

  Ofer

• problems reading output from ffmpeg

  4 août 2016, par JLucas

  I am trying to read raw BGR24 image data from ffmpeg into a C++ application. The C++ application will then process the image further using openCV.
  jpg -> ffmpeg -> application -> openCV

  I started by storing the output from ffmpeg into a file and reading that file from within the application. OpenCV apparently accepts this as it happily displays the image.
  However, it fails when piping the output from ffmpeg directly into stdin of the application.

  I changed the program to just save the input to a file and I compared the two files. The first 1856 bytes are the same, but after that the file saved from stdin differs and after that the entire file is just hex D1 (or decimal 209).

  bytes read from stdin

  bytes read from file

  I presume that I am making a mistake while reading stdin instead of ffmpeg having a different output. But I find it very strange that the first part is the same.
  This is the code I use to read stdin

  char* img = (char*) malloc(FRM_SIZE_BYTES);
  
  cout << "array address: " << &img;
  
  cout << "array of size: " << FRM_SIZE_BYTES << endl;
  
  
  
  int read = int read = read_stdin(img, FRM_SIZE_BYTES);
  
  cout << "read " << read << " bytes" << endl;
  
  
  
  int read_stdin(char* buffer, int count) 
  
  {
  
      int read = 0;
  
      char in;
  
      for (int i = 0; i < count; i++) {
  
          cin >>  in;
  
          buffer[i] = in;
  
          read++;
  
      }
  
      return read;
  
  }

  this is how I try to read the file

  ifstream image;
  
  image.open("img.raw", ios_base::binary | ios_base::in);
  
  std::streampos start, end;  
  
  char* imgFile = (char*)malloc(FRM_SIZE_BYTES);
  
  image.read(imgFile, FRM_SIZE_BYTES);
  
  image.close();

  Any help would be appreciated