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• FFmpeg : Jpeg file to AVFrame

  24 octobre 2012, par darja

  I need to join several jpg files into video using FFmpeg library. But I have a problem with reading this files. Here is a function which reads image file and makes AVFrame :

  AVFrame* OpenImage(const char* imageFileName)
  
  {
  
      AVFormatContext *pFormatCtx;
  
  
  
      if(av_open_input_file(&pFormatCtx, imageFileName, NULL, 0, NULL)!=0)
  
      {
  
          printf("Can't open image file '%s'\n", imageFileName);
  
          return NULL;
  
      }       
  
  
  
      dump_format(pFormatCtx, 0, imageFileName, false);
  
  
  
      AVCodecContext *pCodecCtx;
  
  
  
      pCodecCtx = pFormatCtx->streams[0]->codec;
  
      pCodecCtx->width = W_VIDEO;
  
      pCodecCtx->height = H_VIDEO;
  
      pCodecCtx->pix_fmt = PIX_FMT_YUV420P;
  
  
  
      // Find the decoder for the video stream
  
      AVCodec *pCodec = avcodec_find_decoder(pCodecCtx->codec_id);
  
      if (!pCodec)
  
      {
  
          printf("Codec not found\n");
  
          return NULL;
  
      }
  
  
  
      // Open codec
  
      if(avcodec_open(pCodecCtx, pCodec)<0)
  
      {
  
          printf("Could not open codec\n");
  
          return NULL;
  
      }
  
  
  
      // 
  
      AVFrame *pFrame;
  
  
  
      pFrame = avcodec_alloc_frame();
  
  
  
      if (!pFrame)
  
      {
  
          printf("Can't allocate memory for AVFrame\n");
  
          return NULL;
  
      }
  
  
  
      int frameFinished;
  
      int numBytes;
  
  
  
      // Determine required buffer size and allocate buffer
  
      numBytes = avpicture_get_size(PIX_FMT_YUVJ420P, pCodecCtx->width, pCodecCtx->height);
  
      uint8_t *buffer = (uint8_t *) av_malloc(numBytes * sizeof(uint8_t));
  
  
  
      avpicture_fill((AVPicture *) pFrame, buffer, PIX_FMT_YUVJ420P, pCodecCtx->width, pCodecCtx->height);
  
  
  
      // Read frame
  
  
  
      AVPacket packet;
  
  
  
      int framesNumber = 0;
  
      while (av_read_frame(pFormatCtx, &packet) >= 0)
  
      {
  
          if(packet.stream_index != 0)
  
              continue;
  
  
  
          int ret = avcodec_decode_video2(pCodecCtx, pFrame, &frameFinished, &packet);
  
          if (ret > 0)
  
          {
  
              printf("Frame is decoded, size %d\n", ret);
  
              pFrame->quality = 4;
  
              return pFrame;
  
          }
  
          else
  
              printf("Error [%d] while decoding frame: %s\n", ret, strerror(AVERROR(ret)));
  
      }
  
  }

  This causes no error but creates only black frame, no image. What is wrong ?

• Running ffmpeg commands from android ffmpeg syntax error in logcat

  30 septembre 2015, par Chaitanya Chandurkar

  I have successfully compiled ffmpeg for android and have ported it.

  I placed

  1. libffmpeg.so in /system/lib directory
  2. ffmpeg executable in /system/bin and /system/xbin directory (i was not sure where to place it). i directly copied ffmpeg executable from source directory (Not sure whether it’s a correct way)

  Now i am executing commands from android with following code !!

  imports *
  
  public class LatestActivity extends Activity {
  
  
  
      private Process process;
  
      String command,text;
  
  
  
      static { 
  
          System.loadLibrary("ffmpeg");
  
      }
  
  
  
    @Override
  
      public void onCreate(Bundle savedInstanceState) {
  
          super.onCreate(savedInstanceState);
  
          setContentView(R.layout.activity_latest);
  
  
  
            //Execute Command !!  
  
            try {
  
                 Execute();
  
            } catch (IOException e) {
  
                // TODO Auto-generated catch block
  
                e.printStackTrace();
  
            } catch (InterruptedException e) {
  
                 // TODO Auto-generated catch block
  
                  e.printStackTrace();
  
            }
  
       }
  
  
  
  
  
  
  
  
  
  public void Execute() throws IOException, InterruptedException{
  
          try {
  
              File dir=new File("/system/bin");
  
              String[] cmd= {"ffmpeg","-codecs"};
  
  
  
              process=Runtime.getRuntime().exec(cmd,null,dir);
  
          } catch (IOException e) {
  
              // TODO Auto-generated catch block
  
              Log.d("Process IOException starts:",e.getMessage());
  
              e.printStackTrace();
  
              Log.d("System Manual exit !!",e.getMessage());
  
              System.exit(MODE_PRIVATE);
  
          }
  
  
  
          BufferedReader stdInput = new BufferedReader(new InputStreamReader(process.getInputStream()),16384);
  
  
  
           BufferedReader stdError = new BufferedReader(new InputStreamReader(process.getErrorStream()));
  
  
  
             // read the output from the command
  
             Log.d("Application output: ","Output if any !"); 
  
              while ((text = stdInput.readLine()) != null) {
  
                  Log.d("Output: ",text); //$NON-NLS-1$
  
                 }
  
  
  
  
  
          text="";
  
             // read any errors from the attempted command
  
          Log.d("Application output: ","Errors if any !");  //$NON-NLS-1$
  
             while ((text = stdError.readLine()) != null) {
  
  
  
                 Log.d("Error: ",text);  //$NON-NLS-1$
  
             }
  
  
  
  
  
  
  
             stdInput.close();
  
             stdError.close();
  
  
  
             process.waitFor();
  
             process.getOutputStream().close();
  
             process.getInputStream().close();
  
             process.getErrorStream().close(); 
  
             destroyProcess(process);
  
             //process.destroy();
  
  
  
      }
  
  
  
      private static void destroyProcess(Process process) {
  
          try {
  
              if (process != null) {
  
                  // use exitValue() to determine if process is still running.
  
                  process.exitValue();
  
              }
  
          } catch (IllegalThreadStateException e) {
  
              // process is still running, kill it.
  
              process.destroy();
  
          }
  
      }
  
  
  
    }

  And Here is the logcat output :

  09-05 15:29:13.287: D/dalvikvm(2670): No JNI_OnLoad found in /system/lib/libffmpeg.so 0x44e7e910, skipping init
  
  09-05 15:29:29.117: I/global(2670): Default buffer size used in BufferedReader constructor. It would be better to be explicit if an 8k-char buffer is required.
  
  09-05 15:29:29.117: D/Application output:(2670): Output if any !
  
  09-05 15:29:29.117: D/Application output:(2670): Errors if any !
  
  09-05 15:29:29.127: D/Error:(2670): /system/bin/ffmpeg: 1: Syntax error: "(" unexpected

  m neither getting any errors nor output of command.
  At the end it shows syntax error.
  I want to know what kind of syntax error it is. how to tackle it ?

  m i doing something wrong ?

• Merge commit ’5ecabd3c54b7c802522dc338838c9a4c2dc42948’

  30 mai 2015, par Michael Niedermayer

  Merge commit ’5ecabd3c54b7c802522dc338838c9a4c2dc42948’
  * commit ’5ecabd3c54b7c802522dc338838c9a4c2dc42948’ :
  
    msrle : Use FFABS to determine the frame size in msrle_decode_pal4
  Conflicts :
  
  	libavcodec/msrledec.c
  See : f7e1367f58263593e6cee3c282f7277d7ee9d553
  
  Merged-by : Michael Niedermayer <michaelni@gmx.at>