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• X264 : How to access NAL units from encoder ?

  18 avril 2014, par user1884325

  When I call

  frame_size = x264_encoder_encode(encoder, &nals, &i_nals, &pic_in, &pic_out);

  and subsequently write each NAL to a file like this :

       if (frame_size >= 0)
  
       {
  
          int i;
  
          int j;
  
  
  
          for (i = 0; i < i_nals; i++)
  
          {
  
             printf("******************* NAL %d (%d bytes) *******************\n", i, nals[i].i_payload);
  
             fwrite(&(nals[i].p_payload[0]), 1, nals[i].i_payload, fid);
  
          }
  
       }

  then I get this

  

  My questions are :

  1) Is it normal that there’s readable parameters in the beginning of the file ?

  2) How do I configure the X264 encoder so that the encoder returns frames that I can send via UDP without the packet getting fragmented (size must be below 1390 or somewhere around that).

  3) With the x264.exe I pass in these options :

  "--threads 1 --profile baseline --level 3.2 --preset ultrafast --bframes 0 --force-cfr --no-mbtree --sync-lookahead 0 --rc-lookahead 0 --keyint 1000 --intra-refresh" 

  How do I map those to the settings in the X264 parameters structure ? (x264_param_t)

  4) I have been told that the x264 static library doesn’t support bitmap input to the encoder and that I have to use libswscale for conversion of the 24bit RGB input bitmap to YUV2. The encoder, supposedly, only takes YUV2 as input ? Is this true ? If so, how do I build libswscale for the x264 static library ?

• Access Android phone camera stream using ffmpeg

  14 mars 2016, par Parth Doshi

  I am developing an application that performs live streaming. Currently, I am able to stream a local video from my SD card to my Wowza streaming server successfully.

  This is the command that I fire from my FFMPEG based Android project

   ffmpeg -re -i /sdcard/sample.mp4 -c copy -f flv rtmp://192.168.1.34:1936/live/myStream

  Now, I want to send my camera stream to my streaming server.
  I tried using the below command but it does not work since the /dev/video0 device is denied permission.

     ffmpeg -re -i /dev/video0 -c copy -f flv rtmp://192.168.1.34:1936/live/myStream

  Can anyone tell me the right way to stream the camera feed using ffmpeg on Android

• FFmpeg can't access file in Dropbox on Ubuntu 12.04

  30 juin 2015, par afterglowlee

  I have installed FFmpeg on Ubuntu 12.04. When I use ffmpeg -i command to check some video file online, it works :

  ffmpeg -i http://techslides.com/demos/sample-videos/small.mp4

  However, when I check a public file hosted in my Dropbox it gives ’No such file or directory error’ :

  ffmpeg -i https://dl.dropboxusercontent.com/u/51617581/bigbuck.webm

  and the error is :

  https://dl.dropboxusercontent.com/u/51617581/bigbuck.webm : No such
  file or directory

  and here is the version info of the ffmpeg installation :

  ffmpeg version 0.8.17-4:0.8.17-0ubuntu0.12.04.1, Copyright (c)
  2000-2014 the Libav developers built on Mar 16 2015 13:26:50 with
  gcc 4.6.3

  I have also tried both files on my Mac 10.10 laptop, and both of them work fine. Could anyone suggest where is the problem ? Many thanks.