Newest 'ffmpeg' Questions - Stack Overflow

Les articles publiés sur le site

• NSTask and FFMpeg losing output

  16 novembre 2011, par Morgan

  I'm trying to call ffmpeg from NSTask in objective-c. I execute the ffmpeg command in terminal and it works flawlessly every time. I make the same command using NSTask, and it never gives me the whole output. It cuts it off half way through the output, at a seemingly random spot every time. Here is my code.

      - (void)applicationDidFinishLaunching:(NSNotification *)aNotification
  {
      NSString* ffmpegPath = [[NSBundle mainBundle] pathForResource:@"ffmpeg" ofType:@""];
      NSString* path = @"test.mov";
  
      NSTask *task = [[NSTask alloc] init];
      NSArray *arguments = [NSArray arrayWithObjects: @"-i", path, nil];
      NSPipe *pipe = [NSPipe pipe];
      NSFileHandle * read = [pipe fileHandleForReading];
  
      [task setLaunchPath: ffmpegPath];
      [task setArguments: arguments];
      [task setStandardOutput: pipe];
      [task launch];
      [task waitUntilExit];
  
      NSData* data = [read readDataToEndOfFile];
      NSString* stringOutput = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
  
  
      NSLog(@"%@", stringOutput);
      NSLog(@"%i", [task terminationStatus]);
      NSLog(@"DONE");
  }
  

• WMV Converter Fails FFMpeg

  15 novembre 2011, par zomerc

  I just cann't seem to get the FFMpeg working with using the library. Everytime I try to convert asf file to wmv. I get the following issue on run time:

  [wmv1 @ 0x81ee000]error, slice code was 2 [wmv1 @ 0x81ee000]header damaged

  This my code:

  static void audio_decode_example(const char *outfilename, const char *filename)
  {
      AVCodec *codec;
      AVCodecContext *c= NULL;
      int out_size, len, in_size;
      FILE *f, *outfile;
      uint8_t *outbuf;
      uint8_t inbuf[AUDIO_INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE];
      AVPacket avpkt;
  
      av_init_packet(&avpkt);
  
      printf("Audio decoding\n");
  
      /* find the mpeg audio decoder */
      codec = avcodec_find_decoder(CODEC_ID_WMV1);
      if (!codec) {
          fprintf(stderr, "codec not found\n");
          return;
      }
  
      c= avcodec_alloc_context2(CODEC_TYPE_AUDIO);
  
      /* open it */
      if (avcodec_open(c, codec) < 0) {
          fprintf(stderr, "could not open codec\n");
          return;
      }
  
      outbuf = malloc(AVCODEC_MAX_AUDIO_FRAME_SIZE);
      f = fopen(filename, "rb");
      if (!f) {
          fprintf(stderr, "could not open %s\n", filename);
          return;
      }
      outfile = fopen(outfilename, "wb");
      if (!outfile) {
          av_free(c);
          return;
      }
  
      /* decode until eof */
      avpkt.data = inbuf;
      len = avpkt.size = fread(inbuf, 1, INBUF_SIZE, f);
      NSLog(@"%d", avpkt.size); 
  
      while (avpkt.size > 0) {
          out_size = AVCODEC_MAX_AUDIO_FRAME_SIZE;
      len = avcodec_decode_audio2(c, (short *)outbuf, &out_size, inbuf,len);// avpkt.size);
      NSLog(@"%d", len);
      if (len < 0) {
          fprintf(stderr, "Error while decoding\n");
          fclose(outfile);
          return;
      }
      if (out_size > 0) {
          /* if a frame has been decoded, output it */
          fwrite(outbuf, 1, out_size, outfile);
      }
      avpkt.size -= len;
      avpkt.data += len;
      if (avpkt.size < AUDIO_REFILL_THRESH) {
          /* Refill the input buffer, to avoid trying to decode
           * incomplete frames. Instead of this, one could also use
           * a parser, or use a proper container format through
           * libavformat. */
          memmove(inbuf, avpkt.data, avpkt.size);
          avpkt.data = inbuf;
          len = fread(avpkt.data + avpkt.size, 1,
                      INBUF_SIZE - avpkt.size, f);
          if (len > 0)
              avpkt.size += len;
      }
  }
  
  fclose(outfile);
  fclose(f);
  free(outbuf);
  avcodec_close(c);
  av_free(c);
  }
  

  I have try the command line utilities and it successfully convert the file. Any help would be helpfully. thanks

• Calling ffmpeg convert from bash in iOS ?

  15 novembre 2011, par guoxj

  I can use something like ffmpeg -f mpeg -i src.mpg mpeg4 dest.mp4 to convert src.mpg to dest.mp4 in bash. And I have to port ffmpeg to iOS. How can I use the command in iOS to complete the convert?

• How to determine linux version on server [migrated]

  15 novembre 2011, par chetan

  I purchased a web server recently and have got access to shell on it.Want to install ffmpeg extension on it but I dont know the linux version on the server. I am not used to running linux commands, so can anybody help me in determining the linux version using the shell commands.

• DirectShow / x264 / AviSynth and Windows Server 2008 SP2

  15 novembre 2011, par Tim

  I'm having a hard time getting AviSynth to open video files on Windows Server 2008 SP2 (32 bit). I'm aware of the sound card issue, right now I'm using Audio=false. I've tried installing the below, but I always get the error "No combination of filters could be found to render the stream". I'm using DirectShowSource, but I don't have to ... I'm open that can open most formats your average Windows 7 machine can handle.

  I've installed:

  • "Desktop Extensions" - which installed Media Player and codecs
  • haali media splitter and ffdshow
  • Windows Media Services (for streaming, this supposedly had the mpeg codecs, but it doesn't) Windows Essentials Media Codec Pack
  • K-Lite Codec Pack Full VLC
  • QuickTime Tried copying mpeg.dll codecs from 32 bit Windows 7 to Server and regsvr32'ing them, but get error
  • Tried copying *.AX filters from 32 bit Windows 7 to server and regsvr32'ing, but still get AVS error

  AVS Script:

  • video0 = DirectShowSource("video0.avi", fps=30, pixel_type="RGB24", Audio=false)
  • video1 = DirectShowSource("video1.avi", fps=30, pixel_type="RGB24", Audio=false)
  • Dissolve(video0, video1, 30)

  Command Line:

  • x264 test.avs -o test.mp4 --bframes 3 --ref 3 --vbv-maxrate 2500 --vbv-bufsize=25000 --level 40 --threads

  AVS Error:

  • avs [error]: "No combination of filters could be found to render the stream"

  Has anyone gotten this working on Windows Server? If so what filters codecs or other setup do I need?

  Thank you for the time.