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• Best format for rendering video ffmpeg stream in Android

  16 octobre 2014, par vgokul129

  I’m trying to display ffmpeg video stream in Android using OPENGLES1.0.I tried rendering the frames with AV_PIX_FMT_RGB24 format.It working fine,but i am getting more frame drop and video lag.Can anyone please tell me is there any other image format through which i can render the video frames.Following is a piece of code where i tried already for conversion from AV_PIX_FMT_YUV420P to AV_PIX_FMT_RGB24.

      struct SwsContext *img_convert_ctx = sws_getContext(pCodecCtx->width,pCodecCtx->height,     AV_PIX_FMT_YUV420P,RESOLUTION_WIDTH,RESOLUTION_HEIGHT,AV_PIX_FMT_RGB24, SWS_BICUBIC, NULL,NULL, NULL);
  
      sws_scale(img_convert_ctx,(const uint8_t **) pFrame->data, pFrame->linesize, 0, pCodecCtx->height, pFrameRGB->data, pFrameRGB->linesize);
  
  
  
      glClear(GL_COLOR_BUFFER_BIT);
  
      //Update the data into video memory
  
      glTexSubImage2D(GL_TEXTURE_2D,0,0,0,RESOLUTION_WIDTH,RESOLUTION_HEIGHT,GL_RGB,GL_UNSIGNED_BYTE,pFrameRGB->data[0]);
  
  
  
      glDrawTexiOES(50,50, 0,s_w-100,s_h-100);

• Muxing Audio Over Video Using Ffmpeg

  23 mai 2015, par user1503606

  So i have been through lots of tests and i still cannot seem to get audio to mux over video using ffmpeg and cannot figure where i am going wrong so would really appreciate some help.

  I have this video.
  Video Download

  And if i run ffmpeg -i it gives me this.

   Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, smpte170m/smpte170m/bt709), 366x662 [SAR 1:1 DAR 183:331], 755 kb/s, 24 fps, 24 tbr, 90k tbn, 180k tbc (default)
  
      Metadata:
  
        handler_name    : VideoHandler
  
      Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 105 kb/s (default)

  So stream 0:0

  And i have this piece of audio.
  Audio Download

  and when i run ffmpeg i get this.

  Stream #0:0: Audio: mp3, 44100 Hz, stereo, s16p, 277 kb/s
  
  Stream #0:1: Video: png, rgb24, 400x400, 90k tbr, 90k tbn, 90k tbc

  so what i am look to do is copy my audio 0:0 over to replace the video audio 0:1 without re encoding the whole file.

  ffmpeg -i testing.mp4 -i intro.mp3 -c copy -map 0:1 -map 0:0 -shortest out3.mp4 

  Would really appreciate some help with a working option ran out of possible solutions to try thanks.

• Decode h264 video with csharp

  28 août 2011, par john bowring

  I am looking for a way to decode h264 (or indeed any video format) using c#. The ultimate goal is to be able to decode the images and very strictly control the playback in real time. The project I am working on is a non-linear video art piece where the HD footage is required to loop and edit itself on the fly, playing back certain frame ranges and then jumping to the next randomly selected frame range seamlessly.

  I have created an app which reads image files (jpegs) in from the disk and plays them on screen in order, I have total control over which frame is laoded and when it is displayed but at full HD res it takes slightly longer than I want to load the images from hard drive (which are about 500k each), I am thinking that using a compressed video format would be smaller and therefore faster to read and decode into a particular frame however I cannot find any readily avaiable way to do this.

  Are there any libraries which can do this ? i.e. extract an arbitrary frame from a video file and serve it to my app in less time than it takes to show the frame (running at 25fps), I have looked into the vlc libraries and wrappers for ffmpeg but I don't know which would be better or if there would be another even better option. Also I dont know which codec would be the best choice as some are keyframe based making arbitrary frame extraction probably very difficult.

  Any advice welcome, thanks