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• Adding HEVC reference decoder to ffmpeg framework

  4 mars 2014, par Zax

  I have a tweaked HM reference code of HEVC Decoder based on my requirements. I also know that FFMPEG version 2.1 onwards supports HEVC. But its a necessity for me to integrate my modified HM code.

  Hence I have gone through the post :

  http://wiki.multimedia.cx/index.php?title=FFmpeg_codec_howto

  According to this post, I need to define some functions that are needed to add a new decoder support to FFMPEG framework.

  The structure is : typedef struct AVCodec

  I have defined a structure as shown below :

  AVCodec HMHEVC_decoder =
  
  {
  
      .name           = "hmhevc",
  
      .type           = AVMEDIA_TYPE_VIDEO,
  
      .id             = AV_CODEC_ID_HMHEVC,
  
  
  
      .init           = hmhevc_decode_init,
  
      .close          = hmhevc_decode_close,
  
      .decode         = hmhevc_decode_frame,
  
  };

  However, looking at the other examples, I feel I have to add another variable like :

      .priv_data_size = sizeof(HEVCContext),

  But the problem is that I don't have any such context. So in case I don't define this, what are the things that FFMPEG framework wont provide my decoder ?

  Also is definition of this private data context compulsary ?

  What are the other fields that have to be compulsorily defined ?

  My main intention is that FFPLAY should be able to play the decoded frame.

• Input seeking for frame at specified timestamp with Py-AV

  9 décembre 2019, par neonScarecrow

  I have a project already using Py-AV and am trying to replicate a specific ffmpeg command. The goal is to get a frame roughly around the specified timestamp.

  Here’s the ffmpeg commmand :
  https://trac.ffmpeg.org/wiki/Seeking

  ffmpeg -ss 14 -i https://some_url.mp4 -frames:v 1 frame_at_14_seconds.jpg

  Here’s my code :

      #return one frame around 14 seconds into the movie
  
      target_sec = 14 
  
      container = av.open('https://some_url.mp4', 'r')
  
      container.streams.video[0].thread_type = 'AUTO'
  
      video_stream = next(s for s in container.streams if s.type == 'video')
  
      time_base = float(video_stream.time_base)
  
      target_timestamp = int(target_sec / time_base) + video_stream.start_time
  
      video_stream.seek(target_timestamp)
  
      for frame in container.decode(video_stream):
  
          frame.to_image().save('frame_at_14_seconds.jpg')
  
          break

  Additionally, I have found any documentation about this, but does anyone know if either command (ffmpeg/av.open) is downloading the entire file to a tmp file behind the scenes. I’m looking for a less memory-intensive way to read a frame for every second in an up to 60 second video.

• ffmpeg returned non-zero exit status. Check stdout Coldfusion

  30 mars 2017, par Abdul Rauf

  I have an coldfusion application. I am converting recorded video from mobile through ffmpeg and coldfusion. Here is the ffmpeg command which i am running.

  ffmpegPath -i "inputfile" -vcodec libx264 -acodec aac "OutputFile"

  Output file type is mp4. I want to convert my all videos to mp4 with h.264 and ACC sound. So that it will work on all platforms.

  I am getting the following error :

  java.io.IOException: ffmpeg returned non-zero exit status. Check stdout.

  Here is the CF code that i am running.

  <cfset resultlog="path\to\directory\testOuput_result.log">
  
  <cfset errorlog="path\to\directory\testOuput_error.log">
  
  <cfset results="structNew()"> 
  
          <cfscript>
  
              try {  
  
                  runtime = createObject("java", "java.lang.Runtime").getRuntime();
  
                  command = 'ffmpegPath -i "inputfile" -vcodec libx264 -acodec aac "OutputFile"';
  
                  process = runtime.exec(#command#);
  
                  results.errorLogSuccess = processStream(process.getErrorStream(), errorLog);  
  
                  results.resultLogSuccess = processStream(process.getInputStream(), resultLog);  
  
                  results.exitCode = process.waitFor();  
  
              }  
  
              catch(exception e) {  
  
                  results.status = e;      
  
              }  
  
          </cfscript>
  
  <cffunction access="public" output="false" returntype="boolean" hint="Returns true if stream was successfully processed">  
  
      <cfargument type="any" required="true" hint="java.io.InputStream object">  
  
      <cfargument type="string" required="false" default="" hint="Full path to LogFile">  
  
      <cfset var="var" out="">  
  
      <cfset var="var" writer="">  
  
      <cfset var="var" reader="">  
  
      <cfset var="var" buffered="">  
  
      <cfset var="var" line="">  
  
      <cfset var="var" sendtofile="false">  
  
      <cfset var="var" errorfound="false">  
  
  
  
      <cfscript>  
  
          if ( len(trim(arguments.logPath)) ) {  
  
              out = createObject("java", "java.io.FileOutputStream").init(arguments.logPath);  
  
              writer = createObject("java", "java.io.PrintWriter").init(out);  
  
              sendToFile = true;  
  
          }  
  
  
  
          reader = createObject("java", "java.io.InputStreamReader").init(arguments.in);  
  
          buffered = createObject("java", "java.io.BufferedReader").init(reader);  
  
          line = buffered.readLine();  
  
          while ( IsDefined("line") ) {  
  
              if (sendToFile) {  
  
                  writer.println(line);  
  
              }  
  
              line = buffered.readLine();  
  
          }      
  
             if (sendToFile) {  
  
             errorFound = writer.checkError();  
  
             writer.flush();  
  
             writer.close();  
  
          }  
  
      </cfscript>  
  
        
  
      <cfreturn>  
  
  </cfreturn></cfset></cfset></cfset></cfset></cfset></cfset></cfset></cfargument></cfargument></cffunction> 
  
  </cfset></cfset></cfset>

  I have also used different ffmpeg.exe but got same error. I have also used ffmpeg-cli-wrapper java wrapper in coldfusion. Still i got the same error. Can any one help me to sort out this issue.