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• Merge commit ’c0d973c41b4568d5bad1295879e35cfa611bdcf2’

  12 juillet 2013, par Michael Niedermayer

  Merge commit ’c0d973c41b4568d5bad1295879e35cfa611bdcf2’
  * commit ’c0d973c41b4568d5bad1295879e35cfa611bdcf2’ :
  
    vdpau : use the correct namespace for the union
  Conflicts :
  
  	libavcodec/vdpau.h
  See : 68dfe530e0fb03b4d21dfe37f8a572b95c68485e
  Merged-by : Michael Niedermayer <michaelni@gmx.at>
  

  • [DH] libavcodec/vdpau.h

• j2k/jpeg2000 : split data pointer in int & float.

  30 mai 2013, par Michael Niedermayer

  j2k/jpeg2000 : split data pointer in int & float.
  This fixes a TODO item and unifies both decoders structures
  
  It also fixes undefined behavior due to aliasing violations
  I choose 2 fields instead of a union because mistakely using the
  
  wrong type with a union will lead to hard to debug "wrong output"
  
  while with 2 fields mistakely using the wrong type will crash
  
  with a null pointer derefernce which is much easier to debug
  Signed-off-by : Michael Niedermayer <michaelni@gmx.at>
  

  • [DH] libavcodec/j2k.c
  • [DH] libavcodec/j2k.h
  • [DH] libavcodec/j2kdec.c
  • [DH] libavcodec/j2kenc.c
  • [DH] libavcodec/jpeg2000.c
  • [DH] libavcodec/jpeg2000.h
  • [DH] libavcodec/jpeg2000dec.c

• How to optimize FFMPEG with pipe and memory reuse in Tide SDK

  7 janvier 2014, par Vincent Duprez

  Im running into an speed optimization issue. Im building a video cut tool in web technologies on desktop with TideSDK. On of the tools has a timeline with a position slider

  basically, whenever the slider moves, (using jquery UI), I get the position, translate this into a timecode and asks FFMPEG to encode to a file, when a get the finished event, I simply update the background-image attribute of the 'viewer' to this file. The file is located in some temporary folder.

  The thing is, it is just a bit too slow. Usable, but slow (approx 2 fps on a High end Computer)
  I think there are 2 bottlenecks on this strategy :
   Writing ffmpeg output to a file & reading back in css
   repeatedly loading the same movie file in ffmpeg

  This is the code executed on each move (var timecode is the calculated timecode based on the pointer position)

  var cmd = [FFMPEG];
  
  cmd.push('-y'); //overwrite existing files
  
  cmd.push('-ss',timecode); //CUE position
  
  cmd.push('-i',input); //input file
  
  cmd.push('-f','image2'); //output format
  
  cmd.push('-vframes','1'); //number of images to render
  
  cmd.push(Ti.API.Application.getDataPath( )+"/encoderframe.jpg"); //output file
  
  
  
  var makeframe = Ti.Process.createProcess(cmd);
  
  makeframe.setOnReadLine(function(data){ /*console.log(data);*/ });
  
  var time = new Date().getTime();
  
  makeframe.setOnExit(function(){ ffmpegrunning = false;  $('#videoframe').css('background-image','url(file://'+Ti.API.Application.getDataPath( ).replace(" ","%20")+'/encoderframe.jpg?'+time+')');     });
  
  makeframe.launch();

  Basically, this repeatedly asks the same Command :

  ffmpeg -y -ss 00:00:01.04 -i /somepath/somevideo.mov -f image2 -vframes 1 /path/to/output/encoderframe204.jpg

  How can I optimize this code, Pipe to output straight to css background with Base64 data, or reuse loaded memory file in ffmpeg. ?

  Thanks !