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  • Publier sur MédiaSpip

    13 juin 2013

    Puis-je poster des contenus à partir d’une tablette Ipad ?
    Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir

  • Les formats acceptés

    28 janvier 2010, par

    Les commandes suivantes permettent d’avoir des informations sur les formats et codecs gérés par l’installation local de ffmpeg :
    ffmpeg -codecs ffmpeg -formats
    Les format videos acceptés en entrée
    Cette liste est non exhaustive, elle met en exergue les principaux formats utilisés : h264 : H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 m4v : raw MPEG-4 video format flv : Flash Video (FLV) / Sorenson Spark / Sorenson H.263 Theora wmv :
    Les formats vidéos de sortie possibles
    Dans un premier temps on (...)

  • Encoding and processing into web-friendly formats

    13 avril 2011, par

    MediaSPIP automatically converts uploaded files to internet-compatible formats.
    Video files are encoded in MP4, Ogv and WebM (supported by HTML5) and MP4 (supported by Flash).
    Audio files are encoded in MP3 and Ogg (supported by HTML5) and MP3 (supported by Flash).
    Where possible, text is analyzed in order to retrieve the data needed for search engine detection, and then exported as a series of image files.
    All uploaded files are stored online in their original format, so you can (...)

Sur d’autres sites (6208)

  • Unresolved external symbols using ffmpeg [duplicate]

    27 février 2018, par Edward Severinsen

    I just downloaded the dev package for ffmpeg and was setting up headers and libraries for use. I’m using Visual C++ 2013 and I added the path of the ffmpeg header files and libs. I linked to every single lib file in the ffmpeg lib folder and apparently none of them matched av_register_all and avformat_open_input.

    Here’s the output from trying to build :

    1>------ Build started: Project: ffmpeg_learning, Configuration: Debug Win32 ------
    1>  ffmpeg_learning.cpp
    1>ffmpeg_learning.obj : error LNK2019: unresolved external symbol _av_register_all referenced in function _main
    1>ffmpeg_learning.obj : error LNK2019: unresolved external symbol _avformat_open_input referenced in function _main
    1>c:\users\edward severinsen\documents\visual studio 2013\Projects\ffmpeg_learning\Debug\ffmpeg_learning.exe : fatal error LNK1120: 2 unresolved externals
    ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

    Here’s my code :

    #include "stdafx.h"

    extern "C"
    {
       #include <libavcodec></libavcodec>avcodec.h>
       #include <libavformat></libavformat>avformat.h>
       #include <libswscale></libswscale>swscale.h>
    }

    #pragma comment(lib, "avcodec.lib")
    #pragma comment(lib, "avformat.lib")
    #pragma comment(lib, "swscale.lib")
    #pragma comment(lib, "avdevice.lib")
    #pragma comment(lib, "avutil.lib")
    #pragma comment(lib, "avfilter.lib")
    #pragma comment(lib, "postproc.lib")
    #pragma comment(lib, "swresample.lib")

    int main(int argc, char* argv[])
    {
       av_register_all();

       AVFormatContext* pFormatCtx = NULL;

       //Open video file
       if (avformat_open_input(&amp;pFormatCtx, argv[1], NULL, 0))
       {
           //Couldn't open the file
           return -1;
       }

       return 0;
    }

    I have no idea what I’m missing. Any help would be much appreciated. Thanks.

  • Why does linking different MSVC Run-Time Libraries crash in release mode ?

    9 septembre 2014, par UmNyobe

    I am using ffmpeg and Qt to build a small demo app.

    • FFmpeg is built with /MT (crossbuild or built with visual 2010)
    • Qt is always built with /MD
    • My little example is always built with /MD

    When the application

    int main(int argc, char *argv[])
    {
       QApplication a(argc, argv);

       av_gcd (75, 25);

       return a.exec();
    }

    //note : following is av_gcd source in ffmpeg libs:
    int64_t av_gcd(int64_t a, int64_t b)
    {
       if (b)
           return av_gcd(b, a % b);
       else
           return a;
    }

    is executed in release mode it crashes because it doesn’t see av_gcd as executable memory. The error is :

    First-chance exception at 0x0000000300905a4d in mylittleexample.exe :
    0xC0000005 : Access violation at location 0x0000000300905a4d.

    =======================================
    VERIFIER STOP 0000000000000650 : pid 0x1B9C : Attempt to execute code in
    non-executable memory (first chance).

    0000000300905A4D : Address being accessed.
    0000000300905A4D : Code
    performing invalid access.
    00000000009FF770 : Exception record. Use
    .exr to display it.
    00000000009FF280 : Context record. Use .cxr to
    display it.

    =======================================

    The address 0x0000000300905a4d doesnt change regardless of the function in the library (ffmpeg in this case), or the compiler used for the executable (vs2010, vs2012) or a different machine.

    If I use the FFmpeg built with /MD and it works as one would expect.

    1. I observe that the executable doesnt load the library when the
      library is compiled with /MT. Why is that ?
    2. Furthermore, If the library is compiled with /MT and debug
      information is enabled when the application is linked (/DEBUG
      param to the linker) then the library is loaded and everything
      execute correctly. Why ?
  • FFMPEG compiled binaries don't run using MinGW

    9 juin 2015, par Paul Knopf

    I am trying to build windows executables/dlls for Windows XP, and they are not working. They are the correct architecture. They run fine on my Windows 8 device machine.

    I used dependency walker to find missing DLLs, and all were present.

    Here are the compiled executables I am trying to run.

    I ran the windows build script for ffmpeg.

    Here is a dumpbin /headers ffmpeg.exe

    Microsoft (R) COFF/PE Dumper Version 10.00.30319.01
    Copyright (C) Microsoft Corporation.  All rights reserved.


    Dump of file ffmpeg.exe

    PE signature found

    File Type: EXECUTABLE IMAGE

    FILE HEADER VALUES
                14C machine (x86)
                  7 number of sections
              51A40 time date stamp Sun Jan 04 15:53:20 1970
                  0 file pointer to symbol table
                  0 number of symbols
                 E0 size of optional header
                32F characteristics
                      Relocations stripped
                      Executable
                      Line numbers stripped
                      Symbols stripped
                      Application can handle large (>2GB) addresses
                      32 bit word machine
                      Debug information stripped

    OPTIONAL HEADER VALUES
                10B magic # (PE32)
               2.25 linker version
              41400 size of code
              4FA00 size of initialized data
               1200 size of uninitialized data
               14E0 entry point (004014E0)
               1000 base of code
              43000 base of data
             400000 image base (00400000 to 00456FFF)
               1000 section alignment
                200 file alignment
               4.00 operating system version
               1.00 image version
               4.00 subsystem version
                  0 Win32 version
              57000 size of image
                400 size of headers
              597A9 checksum
                  3 subsystem (Windows CUI)
                140 DLL characteristics
                      Dynamic base
                      NX compatible
             200000 size of stack reserve
               1000 size of stack commit
             100000 size of heap reserve
               1000 size of heap commit
                  0 loader flags
                 10 number of directories
                  0 [       0] RVA [size] of Export Directory
              51000 [    36F0] RVA [size] of Import Directory
                  0 [       0] RVA [size] of Resource Directory
                  0 [       0] RVA [size] of Exception Directory
                  0 [       0] RVA [size] of Certificates Directory
                  0 [       0] RVA [size] of Base Relocation Directory
                  0 [       0] RVA [size] of Debug Directory
                  0 [       0] RVA [size] of Architecture Directory
                  0 [       0] RVA [size] of Global Pointer Directory
              56004 [      18] RVA [size] of Thread Storage Directory
                  0 [       0] RVA [size] of Load Configuration Directory
                  0 [       0] RVA [size] of Bound Import Directory
              517F0 [     6C4] RVA [size] of Import Address Table Directory
                  0 [       0] RVA [size] of Delay Import Directory
                  0 [       0] RVA [size] of COM Descriptor Directory
                  0 [       0] RVA [size] of Reserved Directory


    SECTION HEADER #1
      .text name
      412BC virtual size
       1000 virtual address (00401000 to 004422BB)
      41400 size of raw data
        400 file pointer to raw data (00000400 to 000417FF)
          0 file pointer to relocation table
          0 file pointer to line numbers
          0 number of relocations
          0 number of line numbers
    60500060 flags
            Code
            Initialized Data
            RESERVED - UNKNOWN
            RESERVED - UNKNOWN
            Execute Read

    SECTION HEADER #2
      .data name
        19C virtual size
      43000 virtual address (00443000 to 0044319B)
        200 size of raw data
      41800 file pointer to raw data (00041800 to 000419FF)
          0 file pointer to relocation table
          0 file pointer to line numbers
          0 number of relocations
          0 number of line numbers
    C0700040 flags
            Initialized Data
            RESERVED - UNKNOWN
            RESERVED - UNKNOWN
            RESERVED - UNKNOWN
            Read Write

    SECTION HEADER #3
     .rdata name
       A7D8 virtual size
      44000 virtual address (00444000 to 0044E7D7)
       A800 size of raw data
      41A00 file pointer to raw data (00041A00 to 0004C1FF)
          0 file pointer to relocation table
          0 file pointer to line numbers
          0 number of relocations
          0 number of line numbers
    40700040 flags
            Initialized Data
            RESERVED - UNKNOWN
            RESERVED - UNKNOWN
            RESERVED - UNKNOWN
            Read Only

    SECTION HEADER #4
       .bss name
       1200 virtual size
      4F000 virtual address (0044F000 to 004501FF)
          0 size of raw data
          0 file pointer to raw data
          0 file pointer to relocation table
          0 file pointer to line numbers
          0 number of relocations
          0 number of line numbers
    C0700080 flags
            Uninitialized Data
            RESERVED - UNKNOWN
            RESERVED - UNKNOWN
            RESERVED - UNKNOWN
            Read Write

    SECTION HEADER #5
     .idata name
       36F0 virtual size
      51000 virtual address (00451000 to 004546EF)
       3800 size of raw data
      4C200 file pointer to raw data (0004C200 to 0004F9FF)
          0 file pointer to relocation table
          0 file pointer to line numbers
          0 number of relocations
          0 number of line numbers
    C0300040 flags
            Initialized Data
            RESERVED - UNKNOWN
            RESERVED - UNKNOWN
            Read Write

    SECTION HEADER #6
       .CRT name
         3C virtual size
      55000 virtual address (00455000 to 0045503B)
        200 size of raw data
      4FA00 file pointer to raw data (0004FA00 to 0004FBFF)
          0 file pointer to relocation table
          0 file pointer to line numbers
          0 number of relocations
          0 number of line numbers
    C0300040 flags
            Initialized Data
            RESERVED - UNKNOWN
            RESERVED - UNKNOWN
            Read Write

    SECTION HEADER #7
       .tls name
         20 virtual size
      56000 virtual address (00456000 to 0045601F)
        200 size of raw data
      4FC00 file pointer to raw data (0004FC00 to 0004FDFF)
          0 file pointer to relocation table
          0 file pointer to line numbers
          0 number of relocations
          0 number of line numbers
    C0300040 flags
            Initialized Data
            RESERVED - UNKNOWN
            RESERVED - UNKNOWN
            Read Write

     Summary

           1000 .CRT
           2000 .bss
           1000 .data
           4000 .idata
           B000 .rdata
          42000 .text
           1000 .tls

    When I attempt to run the executable on XP, it just closes. There is no "missing dll" messages, nor anything in the event viewer.