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• lavc : specify the behavior of av_lockmgr_register on failure.

  2 octobre 2014, par Manfred Georg

  lavc : specify the behavior of av_lockmgr_register on failure.
  The register function now specifies that the user callback should
  
  leave things in the same state that it found them on failure but
  
  that failure to destroy is ignored by the library.  The register
  
  function is now explicit about its behavior on failure
  
  (it unregisters the previous callback and destroys all mutex).
  Signed-off-by : Manfred Georg <mgeorg@google.com>
  
  Signed-off-by : Anton Khirnov <anton@khirnov.net>
  

  • [DH] libavcodec/avcodec.h
  • [DH] libavcodec/utils.c
  • [DH] libavcodec/version.h

• FFMPEG sendcmd command limitation

  18 novembre 2022, par Stahlauge

  i try to draw text into a video with drawtext and sendcmd.
In the sendcmd file there are over 9100 commands defined (each frame needs a different text).
All my commands are build this way.

  


  0 Parsed_drawtext_1 reinit 'text=\102030GA01, 102040Ap05
von oben, in Fließrichtung
[0,00]   17.11.2022 10\:22\:04:fontsize=28.928569157918293:y=5:x=0:fontcolor=#FFFFFF';
0.04 Parsed_drawtext_1 reinit 'text=\102030GA01, 102040Ap05
von oben, in Fließrichtung
[0,00]   17.11.2022 10\:22\:04:fontsize=28.928569157918293:y=5:x=0:fontcolor=#FFFFFF';
0.08 Parsed_drawtext_1 reinit 'text=\102030GA01, 102040Ap05
von oben, in Fließrichtung
[0,00]   17.11.2022 10\:22\:05:fontsize=28.928569157918293:y=5:x=0:fontcolor=#FFFFFF';


  


  My command is.

  


  ffmpeg.exe -y -i "17112022_102204.mp4" -vf "sendcmd=f=drawtextcommands.cmd,drawtext=fontfile='Ubuntu-L.ttf':text=:fontcolor=black@1.0:line_spacing=5, drawtext=fontfile='Ubuntu-L.ttf':text=:fontcolor=yellow@1.0:line_spacing=5,drawtext=fontfile='Ubuntu-L.ttf':text=:fontcolor=yellow@1.0:line_spacing=5,drawtext=fontfile='Ubuntu-L.ttf':text=:fontcolor=green@1.0:line_spacing=5" -c:v mpeg4 -qscale:v 5 -f mp4 "102030GA01_2022-11-17_10-21.mp4"


  


  My ffmpeg Version is n5.0.4 lgpl.
If i run this command with the sendcmd file on my develop laptop it works just fine (i7-10850H and 32GB RAM) but if i run the excat same on a Surface (i5-1035G4 and 8GB RAM) or Dell Latitude 5175 (Intel m5-6Y57 and 8GB RAM) i get an error

  


  [Parsed_sendcmd_0 @ 000002454188c540] No Targed specified in interval #XXXX, command #0 


  


  where XXXX is different each time i run it. All PC runs Win 10.

  


  I can´t really find the problem why i get this error on the tablets but not on my Laptop.
Maybe it´s a hardware ressource problem even FFMEG doesn´t have any requirements at all ?

  


  I only can get it to run on the tablets if i delete lots of commands from the sendcmd file.
I can´t define excatly the amount i need to delete because each run i can have more or less commands that are working.
But i can say i need to delete a lot more commands on the Dell tablet then on the Surface on to get it to run.

  


• Android sws_scale RGB Frame taking long time and cause of latency in the video

  17 avril 2018, par AJit

  I am reading frames from FFMPEG and try to directly draw to surface window in Native android, If i scale image to exact size what we are getting from camera and apply YUV420P to RGBA it take 1ms to scale through av_image_fill_arrays but if i try to scale image what i need for surface, then i take 25 to 30ms to scale same frame. so latency is the problem.

  In below example getting YUV420P pixel format.

  Low latency :[ 1ms by sws_scale]

  swsContext = sws_getContext(videoCodecContext->width,
  
                                      videoCodecContext->height,
  
                                      videoCodecContext->pix_fmt,
  
                                      videoCodecContext->width,
  
                                      videoCodecContext->height,
  
                                      AV_PIX_FMT_RGB0,
  
                                      SWS_FAST_BILINEAR, NULL, NULL, NULL);
  
  av_image_fill_arrays()
  
  av_read_frame()
  
  avcodec_decode_video2(
  
  sws_scale(swsContext,
  
            (const uint8_t *const *) videoFrame->data,
  
            videoFrame->linesize,
  
            0,
  
            videoCodecContext->height,
  
            pictureFrame->data,
  
            pictureFrame->linesize);
  
  ANativeWindow_lock()
  
  Write all buffer bytes to window.
  
  ANativeWindow_unlockAndPost()

  Low latency :[ 30ms by sws_scale]

  [videoContext Width: 848 Height: 608]
  
  swsContext = sws_getContext(videoCodecContext->width,
  
                                      videoCodecContext->height,
  
                                      videoCodecContext->pix_fmt,
  
                                      1080,
  
                                      608,
  
                                      AV_PIX_FMT_RGB0,
  
                                      SWS_FAST_BILINEAR, NULL, NULL, NULL);

  Whenever we change context width and height other then videoContext it will take more then 30ms and we are delaying the video.

  TRY 1 : Pass the buffer from JNI to Java and create bitmap there to scale later on but createBitmap itself take 500ms so no useful.

  TRY 2 : Direct YUV420P to RGB conversion. still long time then sws_scale.

  TRY 3 : Direct write YUV to window bites but it show without color(If anyone have solution here will might helpful).

  TRY 4 : Use yuvlib, no luck.

  TRY 5 : Different color combinations and flags in swsContext.

  Any help would appreciated.