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• Need help correcting Access Violation with FFmpeg DLL

  26 septembre 2012, par James

  I'm trying to use the FFmpeg dll's using Visual Studio 2012 and I'm getting a run time access violation when I call avcodec_find_encoder. Here is the code:

  // TestFFmpeg.cpp : Defines the entry point for the console application.
  //
  
  #include "stdafx.h"
  
  extern "C" {
  #include "libavcodec\avcodec.h"
  #include "libavformat\avformat.h"
  }
  
  #define INBUF_SIZE 4096
  
  int _tmain(int argc, _TCHAR* argv[])
  {
      AVCodec *codec;
  
      const char *videoFilename = "C:\\Users\\Public\\Videos\\Sample Videos\\Wildlife.wmv";
  
      av_register_all(); // This works; however, no parameters or return values.
  
      codec = avcodec_find_encoder(CODEC_ID_WMV3);  // Run time Access Violation HERE
      if (!codec) {
      fprintf(stderr, "Codec not found\n");
          exit(1);
      }
  
      return 0;
  }
  

  Here is the error message:

  Unhandled exception at 0x75C18B60 (msvcrt.dll) in TestFFmpeg.exe: 0xC0000005: Access violation reading location 0x00000049.

  The stack trace is:

      msvcrt.dll!_strcmp()    Unknown
      avcodec-54.dll!6a56caac()   Unknown
      [Frames below may be incorrect and/or missing, no symbols loaded for avcodec-54.dll]    
  >   TestFFmpeg.exe!wmain(int argc, wchar_t * * argv) Line 23    C++
      TestFFmpeg.exe!__tmainCRTStartup() Line 533 C
      TestFFmpeg.exe!wmainCRTStartup() Line 377   C
      kernel32.dll!@BaseThreadInitThunk@12()  Unknown
      ntdll.dll!___RtlUserThreadStart@8() Unknown
      ntdll.dll!__RtlUserThreadStart@8()  Unknown
  

  I'm guessing there's a problem with returning the codec pointer, but I'm new to C++ and have no idea how to correct it. I tried the cdecl, stdcall, and fastcall calling conventions -- none corrected the issue. I'm using the latest 32-bit DLL from Zeranoe. Any suggestions?

  EDIT: I've called other functions in the DLL and they work. For example, avformat_open_input works properly. I can pass parameters and the function returns a successful return value (0) and populates the format context structure. av_find_stream_info works as well. I still can't figure out why avcodec_find_decoder creates an access violation.

• FFMPEG Segmenting skips when m3u8 changes file

  25 septembre 2012, par user792164

  I am attempting to segment a large video file in to segments. When streamed (even locally) by opening the m3u8 file it will jump forward in time by some period of time less than 1 second.

  The following commands are executed:

  First mp4 --> ts:

  ffmpeg -i input_file.mp4 -bsf:v h264_mp4toannexb -acodec libfaac -vcodec libx264 -f mpegts -threads 0 output.ts
  

  Then I split using:

  ffmpeg -i output.ts -vcodec copy -acodec copy -map 0 -f segment -segment_time 30 -segment_list output.m3u8 -segment_list_type m3u8 -segment_format mpegts output%03d.ts 
  

  Note: Changing segment time has no effect on issue.

  Generated manifest:

  #EXTM3U
  #EXT-X-VERSION:4
  #EXTINF:30.947578,
  output000.ts
  #EXTINF:30.155111,
  output001.ts
  ...
  #EXTINF:24.023989,
  output082.ts
  #EXT-X-TARGETDURATION:37
  #EXT-X-ENDLIST
  

  ---

  Meta Data:

  $> ffmpeg -version
  ffmpeg version git-2012-08-19-a93c221
  built on Aug 19 2012 13:18:58 with gcc 4.4.5 (Debian 4.4.5-8)
  configuration: --prefix=/usr --bindir=/usr/bin --datadir=/usr/share/ffmpeg --incdir=/usr/include/ffmpeg --libdir=/usr/lib/ --mandir=/usr/share/man --extra-cflags='-O3 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions \ -fstack-protector --param=ssp-buffer-size=4 -mtune=generic' --enable-gpl --enable-shared --enable-nonfree --enable-version3 --enable-libfaac --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-librtmp --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-pthreads --enable-libxvid --enable-postproc --enable-libgsm --enable-libspeex --enable-avfilter --disable-decoder=libdirac --enable-libfreetype --enable-libschroedinger --disable-decoder=libschroedinger --enable-libopenjpeg --disable-ffplay --disable-ffserver
  libavutil      51. 70.100 / 51. 70.100
  libavcodec     54. 53.100 / 54. 53.100
  libavformat    54. 25.104 / 54. 25.104
  libavdevice    54.  2.100 / 54.  2.100
  libavfilter     3. 11.101 /  3. 11.101
  libswscale      2.  1.101 /  2.  1.101
  libswresample   0. 15.100 /  0. 15.100
  libpostproc    52.  0.100 / 52.  0.100
  

  -

  $> ffprobe input_file.mp4
  
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'input_file.mp4':
  Metadata:
  major_brand     : isom
  minor_version   : 1
  compatible_brands: isom
  creation_time   : 2011-09-08 11:43:25
  Duration: 00:41:31.00, start: 0.000000, bitrate: 1146 kb/s
  Stream #0.0(und): Video: h264 (High), yuv420p, 720x404 [PAR 1:1 DAR 180:101], 1015 kb/s,    23.98 fps, 23.98 tbr, 24k tbn, 47.95 tbc
  Metadata:
    creation_time   : 2011-09-08 11:43:25
  Stream #0.1(und): Audio: aac, 48000 Hz, stereo, s16, 124 kb/s
  Metadata:
    creation_time   : 2011-09-08 11:43:25
  

  -

  $> ffprobe output_file.ts
  Input #0, mpegts, from 'output_file.ts':
  Duration: 00:41:30.98, start: 1.400000, bitrate: 807 kb/s
  Program 1 
  Metadata:
    service_name    : Service01
    service_provider: FFmpeg
  Stream #0.0[0x100]: Video: h264 (High), yuv420p, 720x404 [PAR 1:1 DAR 180:101], 23.98 fps, 23.98 tbr, 90k tbn, 47.95 tbc
  Stream #0.1[0x101](und): Audio: aac, 48000 Hz, stereo, s16, 141 kb/
  

  ---

  Is it possible to remove this jump, if so, what encoding parameters or incorrect assumptions have I made? Thanks.

• FFMPEG FLV to 3GP more than 176x144 size

  25 septembre 2012, par Tom

  Hi all I am converting my.flv to my.gp3 with this command

  ffmpeg -i my.flv -acodec libamr_nb -s 176x144 -ar 8000 -b 120000 -vcodec h263 -ab 10.2k -ac 1 my.3gp
  

  but size of my flv is 320x240 and I am trying change 176x144 to 320x240 but getting 3gp file with 0kb , how can I do that and get my.3gp file with same size like my.flv

  And one more thing , the my.flv is product of converting from my.swf(vide) , if you know some command which will do swf->3gp with same size it would be better . Thanks a lot.

• How do I correctly convert .avi to .flv with ffmpeg ? [closed]

  25 septembre 2012, par terbooter

  UPDATE Shame on me ) I chacked red5 logs again and found that I placed converted files to wrong place. Now all works fine

  I have two red5 apps.

  1. Recorder. It can record live stream and save it to flv file to disk

     private void startRecord(String uid, String name, IConnection connection) {
         // Get a reference to the current broadcast stream.
         ClientBroadcastStream stream = (ClientBroadcastStream) this.getBroadcastStream(
                 connection.getScope(), name);
         try {
             // Save the stream to disk.
             String path = uid + "/" + name;
             stream.saveAs(path, true);
     
             System.out.println("file..:" + stream.getSaveFilename());
     
         } catch (Exception e) {
             System.out.println("Error while saving stream: " + name + e);
         }
     }
     
     private void stopRecord(String name) {
         IConnection conn = Red5.getConnectionLocal();
         System.out.println("Stop recording show for: {}" + conn.getScope().getContextPath());
     
         ClientBroadcastStream stream = (ClientBroadcastStream) this.getBroadcastStream(conn.getScope(), name);
         // Stop recording.
         if (stream != null) {
             stream.stopRecording();
         }
     }
     

  2. Second red5 app (Chat) streams recorded flv file to flash client

     public static String serverStreamCreate(String path, String streamName) {
     
         IServerStream serverStream = StreamUtils.createServerStream(Red5.getConnectionLocal().getScope(), streamName);
         SimplePlayItem item = SimplePlayItem.build(path);
     
         IPlaylistController controller = new MyPlayListController();
     
         serverStream.setPlaylistController(controller);
         serverStream.setRepeat(false);
         serverStream.addItem(item);
         serverStream.addItem(item);
         serverStream.start();
         return streamName;
     }
     

  If I record stream from flash client to flv file with Recorder and after that stream this flv file back to client with Chat, all works fine.

  Now I want to convert avi file to flv and stream it from red5 app to flash client. I used ffmpeg

  ffmpeg -i 24.avi -ar 22050 -an -f flv -b 500k -s 320x240 -y 24_c.flv
  

  But if I stream 24_c.flv from Chat app flash client have no video. 24_c.flv cant be playd by VLC player and have same code information as flv file created by Recorder red5 app.

  I really dont know where to dig.

• Working FFMPEG settings for converting to WebM format ? [migrated]

  25 septembre 2012, par Tony

  Can anyone give me working settings for converting video to WebM with ffmpeg?

  I am on Windows 7 with the FFmpeg git-67f5650 64-bit Static (Latest) build from http://ffmpeg.zeranoe.com/builds/

  I've tried several settings found on google, a couple of different input formats and even "all default" settings like ffmpeg -i a.wmv -f webm a.webm and still ffmpeg just gives me a "stopped working" error.

  Thanks in advance!