Recherche avancée

Sur d’autres sites (7212)

• C Code Using FFmpeg libraries - Compilation Error

  17 août 2013, par Ardatr

  I've been recently trying to compile C code that uses the FFmpeg libraries ; however, the compilation fails due to a reason that I cannot determine.

  The code that I've been trying to compile is the filtering_audio.c file on the Doxygen Documentation website for FFmpeg (I'll provide the link, since the code is too long to quote here) : http://ffmpeg.org/doxygen/trunk/doc_2examples_2filtering_audio_8c-example.html

  I use gcc to compile the code :

      gcc filter.c -lavformat -lavcodec -lavfilter  -lavutil

  And I get the following undefined reference errors :

      /tmp/cc90K2S5.o: In function `init_filters':
  
      filter.c:(.text+0x3e5): undefined reference to `av_int_list_length_for_size'
  
      filter.c:(.text+0x407): undefined reference to `av_int_list_length_for_size'
  
      filter.c:(.text+0x42d): undefined reference to `av_opt_set_bin'
  
      filter.c:(.text+0x482): undefined reference to `av_int_list_length_for_size'
  
      filter.c:(.text+0x4a4): undefined reference to `av_int_list_length_for_size'
  
      filter.c:(.text+0x4ca): undefined reference to `av_opt_set_bin'
  
      filter.c:(.text+0x51f): undefined reference to `av_int_list_length_for_size'
  
      filter.c:(.text+0x541): undefined reference to `av_int_list_length_for_size'
  
      filter.c:(.text+0x567): undefined reference to `av_opt_set_bin'
  
      /tmp/cc90K2S5.o: In function `print_frame':
  
      filter.c:(.text+0x76b): undefined reference to `av_frame_get_channel_layout'
  
      /tmp/cc90K2S5.o: In function `main':
  
      filter.c:(.text+0x831): undefined reference to `av_frame_alloc'
  
      filter.c:(.text+0x83d): undefined reference to `av_frame_alloc'
  
      filter.c:(.text+0x9de): undefined reference to `av_buffersrc_add_frame_flags'
  
      filter.c:(.text+0xa16): undefined reference to `av_buffersink_get_frame'
  
      filter.c:(.text+0xa58): undefined reference to `av_frame_unref'
  
      filter.c:(.text+0xab6): undefined reference to `av_frame_free'
  
      filter.c:(.text+0xac5): undefined reference to `av_frame_free'
  
      collect2: error: ld returned 1 exit status

  I understand that the undefined reference error indicates that it wasn't able to find the functions referenced from filtering_audio.c, but this doesn't make sense, since these functions should exist in the FFmpeg libraries.

  Any help is appreciated, thank you !

• configure : Include quotes around pkg_version

  16 décembre 2024, par Joe Schiffler

  configure : Include quotes around pkg_version
  In some MSYS environments it can happen that the 3 argument syntax
  
  for pkg-config library specifications fails because somehow the
  
  expansion of pkg_version ends up with a redirection we guess.
  To avoid failures like in the referenced build[2], we quote it
  
  so the whole module including operators will be expanded into
  
  a single shell word and the single argument syntax for specifying
  
  the library for pkg-config will be used.
  The single argument syntax seems to be supported by the original
  
  pkg-config from the beginning more than 20 years[3].
  In the pkgconf implementation single argument syntax was supported
  
  pretty much from the beginning as well. The multiple argument syntax
  
  we used until this change, was not supported until a change[4] more
  
  than 10 years ago.
  References
  
  1. Build passing with quotes :
  
     https://github.com/JoeSchiff/pyav-ffmpeg/actions/runs/12358403929
  
  2. Build failing without quotes :
  
     https://github.com/JoeSchiff/pyav-ffmpeg/actions/runs/12360472377
  
  3. Earliest commit of the current pkg-config Git repo already mentions the single argument syntax :
  
     https://gitlab.freedesktop.org/pkg-config/pkg-config/-/commit/2ac96cbcc708d8945329fd1b2001386e1c895c64#124c0becfe68b1ef671f49ed2b9d24779ace126f_0_162
  
  4. pkgconf gets support for 3 argument syntax (pkgconf —exists liba = 1.2.3) :
  
     https://github.com/pkgconf/pkgconf/commit/793de6a06ca52fbfe906a269b5f2b2ba41739517
  Commit-message-by : Alexander Strasser <eclipse7@gmx.net>
  
  Signed-off-by : Joe Schiffler <joeschiffler3@gmail.com>
  
  Signed-off-by : Alexander Strasser <eclipse7@gmx.net>
  

  • [DH] configure

• Revision 37011 : Un petit test pour voir si ffmpeg2theora est dispo sur le serveur (pour ...

  6 avril 2010, par kent1@… — Log

  Un petit test pour voir si ffmpeg2theora est dispo sur le serveur (pour l’utiliser au cas où plus tard)