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• Merge commit ’4ab496261b12e20ef293b7adca4fcaef1a67c538’

  19 mars 2017, par James Almer

  Merge commit ’4ab496261b12e20ef293b7adca4fcaef1a67c538’
  * commit ’4ab496261b12e20ef293b7adca4fcaef1a67c538’ :
  
    libvpx : Cast a pointer to const to squelch a warning
  This commit is a noop, see 09b3bbe6057c9d03dff2467b1e6748a617afea15
  Merged-by : James Almer <jamrial@gmail.com>
  

• FFprobe reading incorrect resolution value despite players rendering it correctly

  24 juillet 2015, par Boehmi

  I’m creating a video from a stream with the help of FFMPEG and I also use FFPROBE to gather information for use on a status page like resolution, codecs et cetera.

  When FFProbe parses my video for information, I get a resolution value of 544x576 (almost a square !), but an aspect ratio of 16:9.

  These values are consistent on both the input stream and my saved video.

  When I watch the video in the standard HTML5 Player, VLC or FFPLAY however, I get a video with the proportions of 16:9 and a resolution (measured using an image editing program) of 1024x576 that does look native and not stretched in any way.

  Even if I re-encode the video using slightly different codecs, this incorrect resolution value persists, even though every player I use displays it correctly.

  This is slightly inconvenient because I am relying on getting the correct resolution value from the video for further processing.

  I’m also using a recent FFMPEG+FFPROBE version that was compiled on the 15th of July.

  Is this a bug within FFMPEG or is there anything I’m doing wrong ?

  Used command lines :

  FFMPEG :

  ffmpeg -i source -loglevel debug -vcodec copy -acodec copy -bsf:a aac_adtstoasc -movflags +faststart -t 360 -y video.mp4

  FFPROBE (I parse the output of this directly and save the values) :

  ffprobe -i source -show_format -show_streams 

  FFProbe output :

  width=544
  
  height=576
  
  coded_width=544
  
  coded_height=576
  
  has_b_frames=2
  
  sample_aspect_ratio=32:17
  
  display_aspect_ratio=16:9

  I can see that the sample aspect ratio is different from the display aspect ratio, but how come the video looks proper in 16:9 when it’s supposedly encoded at a near square resolution ?

• ffserver webm streaming issue with Firefox browser

  1er septembre 2015, par Venkatesh Babu Dargah

  I’m attempting to cast my desktop screen to an ffserver and stream it as a webm. I’m using the following ffserver configuration :

  HTTPPort 8091
  MaxHTTPConnections 20000
  MaxClients 10000
  MaxBandwidth 10000

  CustomLog -

  File /tmp/feed1.ffm
  FileMaxSize 1G
  ACL allow 127.0.0.1

  Format webm
  Feed feed1.ffm

  Video settings

  VideoCodec libvpx
  
  VideoFrameRate 30
  
      VideoBitRate 512
  
  VideoSize 320x240
  
      MaxTime 0
  
      AVOptionVideo me_range 16
  
      AVOptionVideo qdiff 4
  
      AVOptionVideo qmin 4
  
      AVOptionVideo qmax 40
  
      AVOptionVideo quality good
  
      AVOptionVideo flags +global_header

  Streaming settings

      PreRoll 10
  
      StartSendOnKey 

  Audio settings

      AudioCodec libopus
  
      AudioBitRate 128
  
      AudioSampleRate 48000
  
      AVOptionAudio flags +global_header
  
      Metadata author "author"
  
      Metadata copyright "copyright"
  
      Metadata title "Web app name"
  
      Metadata comment "comment"

  I am using ffmpgeg to capture video from my desktop using
  ffmpeg -f v4l2 -s 320x240 -r 25 -i /dev/video0 -f alsa -ac 2 -i hw:0 http://localhost:8091/feed1.ffm/

  i am able to see this stream in chrome.
  but Firefox is showing message as MIME type not supported and not able to decode.
  but if I run the same webm video from static file it is playing in firefox
  but if I try to access via http://localhost:8091/live1.webm i am getting MIME type error,
  please let me know what additional settings need to be done in Firefox to play webm videos from my server address and port.
  Again I am reiterating that this is playing ok in chrome but not in Firefox.

  Please reply.

  hi all,

  i am able to play in firefox also after i changed audiocodecs to libvorbis and removing AudioChannels parameter from ffserver config file.

  thanks for your attention