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• Anomalie #4187 (Fermé) : Connecté en Anglais (langue principale français) pas de bouton pour ajout...

  8 février 2021, par cedric -

  Et je ferme ici car le bug ne concerne pas SVP mais extraire_multi, et donc on traite le problème dans

  #4189

• Windows Pipes STDIN and STDOUT Parent Child proc communication IPC FFMPEG

  15 octobre 2018, par Evren Bingøl

  I am writing a simple WINDOWS app which demonstrates piping,

  I pass byte size data down to child proc, increment the value and send the char size data back to parent and loop until it reaches MAX_CHAR
  Pretty much demonstration of "i++" with IPC.

  Parent Process

  while(i<256){
  
      bSuccess = WriteFile(g_hChildStd_IN_Wr, chBuf, sizeof(char), &dwWritten, NULL);
  
      bSuccess = ReadFile(g_hChildStd_OUT_Rd, chBuf, sizeof(char), &dwRead, NULL); // IF THERE IS NO FFLUSH IT BLOCKS
  
  }

  And in Child

  while (i<256){
  
          byte data=0;
  
          fread(&data, sizeof(char), 1, stdout);
  
          data++;
  
          fwrite(&data, sizeof(char), 1, stdout);
  
          //fflush(stdout); IF I DO NOT HAVE THIS  PARENT BLOCKS ON READ
  
  }

  First of all if I do not FFLUSH child proc stdout, the parent blocks on reading child’s stdout.

  How can one run this code without having to fflush child’s stdout.

  Closing the pipe after child’s first write is not an option as it is in a loop and needs to execute 256 times.

  more generically I want the child to write N bytes to parent, parent read that N bytes do something and write back to child another N bytes and child does something with that N bytes and write to parent N bytes. This happens M times.

  thing is I can not use fflush because my final goal is to use a child process that is not implemented by me.

  My final goal is to pipe data to FFMPEG encode the data and read back from the stdin and do this over and over again with out having to fork a new FFMPEG process for each image frame but rather fork one instance of FFMPEG and pipe data in and read data out from it. And since I did not implement ffmpeg and I can not change the source code.

  thanks

  Thanks

• Android ICS FFMPEG scale video not working

  20 avril 2015, par Android-Developer

  I am using Guardian Project Android Java FFMPEG library to resize videos. Current code which is working on android 5.0.1 / 5.1.0 / 4.4.4 :

      File fileTmp = getCacheDir();
  
      FfmpegController fc = null;
  
      try {
  
          fc = new FfmpegController(this, fileTmp);
  
      } catch (IOException e) {
  
          e.printStackTrace();
  
      }
  
      String path = Environment.getExternalStorageDirectory().getPath() + "/Movies/nexus.mp4";
  
      final String outPath = Environment.getExternalStorageDirectory().getPath() + "/Movies/test.mp4";
  
      final Clip out = new Clip(path);
  
      try {
  
          if (fc != null) {
  
              fc.convert(out, outPath, new ShellUtils.ShellCallback() {
  
                  @Override
  
                  public void shellOut(String shellLine) {
  
                      Log.e("", "SHELL OUT: " + shellLine);
  
                  }
  
  
  
                  @Override
  
                  public void processComplete(int exitValue) {
  
                      Log.e("", "PROCESS COMPLETE: " + exitValue);
  
                  }
  
              });
  
          }
  
      } catch (Exception e) {
  
          e.printStackTrace();
  
      }

  Using this code on Android 4.0.4 (Ice Cream Sandwich) doesn’t do anything. While testing on other devices exitValue in processComplete is always equal to 0, but on ICS it’s 11. Here is the output in LogCat :

  SHELL OUT: /data/data/org.hardartcore.ffmpeg/app_bin/ffmpeg -y -i /mnt/sdcard/Movies/NEXUS.mp4 -ab 160k -r ntsc-film -vf scale=568:320 -strict -2 /mnt/sdcard/Movies/Test.mp4
  
  PROCESS COMPLETE: 11

  I don’t think it’s something from ffmpeg, more like a problem when the library is trying to execute ffmpeg executable from raw folder in internal memory, but I can’t see any logs or errors which indicate that too.

  So my question is, if there is any mistake which I am doing using / running this code or something which can prevent ffmpeg executable from running on old devices with Android ICS ?

  Thanks in advance !