Recherche avancée

Sur d’autres sites (8873)

• FFmpeg's "Bitrate Tolerance" and "MPEG Version" Options

  10 mars 2012, par RRN

  I am using FFCoder.

  In "Rate Control" -> "Bitrate Tolerance" is set to '1.0'

  What does it mean ?

  I checked the FFmpeg docs, it explains this is "in bits", default=4000k, so 1.0 seems not reasonable here... anybody know ?

  ‘-bt tolerance’
  Set video bitrate tolerance (in bits, default 4000k). Has a minimum value of : (target_bitrate/target_framerate). In 1-pass mode, bitrate tolerance specifies how far ratecontrol is willing to deviate from the target average bitrate value. This is not related to min/max bitrate. Lowering tolerance too much has an adverse effect on quality.

  By the way, for "AAC" audio codec, the "MPEG Version" can be set to "MPEG-4" or "MPEG-2", what is the corresponding FFmpeg's option ??

  Thanks !!

• Generating 64kbps audio-only mpegts for HTTP Live segmenter to meept 64kbps audio only requirement

  23 avril 2012, par Pobre

  I am trying to convert our mp4 files into mpeg-ts and segment it into .ts files for my iphone app to play. I am using Carson McDonalds's HTTP-Live-Video-Stream-Segmenter-and-Distributor to do that.

  I got his stuff complied and working correctly. I am currently trying to meet Apple's requirement where I need to provide a baseline 64 kbps audio only stream to my m3u8 playlist.
  Carson doesn't seem to have a profile for that.

  I need to be able to generate 64kbps audio-only stream from mp4, and turn that into mpeg-ts for the segmenter into ts. I am trying to find the right ffmpeg command that will validate without problem using Apple's mediastreamvalidator.

  So far I modified an existing encoding profile to try to achieve 64kbps total :

  ffmpeg -er 4 -i %s -f mpegts -acodec libmp3lame -ar 22050 -ab 32k -s 240x180 -vcodec libx264 -b 16k -flags +loop+mv4 -cmp 256 -partitions +parti4x4+partp8x8+partb8x8 -subq 7 -trellis 1 -refs 5 -coder 0 -me_range 16 -keyint_min 25 -sc_threshold 40 -i_qfactor 0.71 -bt 64k -maxrate 16k -bufsize 16k -rc_eq 'blurCplx^(1-qComp)' -qcomp 0.6 -qmin 10 -qmax 51 -qdiff 4 -level 30 -aspect 4:3 -r 10 -g 30 -async 2 - | %s %s %s %s %s

  but then when I try to validate it using mediastreamvalidator, it gives error after few ts :

  Playlist Validation : OK

  Segments :

  sample_cell_4x3_64k-00001.ts :

  WARNING : Media segment exceeds target duration of 10.00 seconds by 1.30 seconds (segment duration is 11.30 seconds)

  sample_cell_4x3_64k-00002.ts :

  WARNING : Media segment exceeds target duration of 10.00 seconds by 1.40 seconds (segment duration is 11.40 seconds)

  ....
  ....

  sample_cell_4x3_64k-00006.ts :

  ERROR : (-1) Unknown video codec : 1836069494 (program 0, track 0)
  ERROR : (-1) failed to parse segment as either an MPEG-2 TS or an ES

  sample_cell_4x3_64k-00007.ts :

  ERROR : (-1) Unknown video codec : 1836069494 (program 0, track 0)
  ERROR : (-1) failed to parse segment as either an MPEG-2 TS or an ES

  ....
  ....
  Average segment duration : 10.26 seconds
  Average segment bitrate : 376797.92 bps
  Average segment structural overhead : 349242.17 bps (92.69 %)

  Is there someway I can generate this correctly with just audio which totals 64kbps and turn it into mpeg-ts ready to be segmented and validated correctly ?

  Am I approaching the problem right ?

• DirectShow / x264 / AviSynth and Windows Server 2008 SP2

  15 novembre 2011, par Tim

  I'm having a hard time getting AviSynth to open video files on Windows Server 2008 SP2 (32 bit). I'm aware of the sound card issue, right now I'm using Audio=false. I've tried installing the below, but I always get the error "No combination of filters could be found to render the stream". I'm using DirectShowSource, but I don't have to ... I'm open that can open most formats your average Windows 7 machine can handle.

  I've installed :

  • "Desktop Extensions" - which installed Media Player and codecs
  • haali media splitter and ffdshow
  • Windows Media Services (for streaming, this supposedly had the mpeg codecs, but it doesn't) Windows Essentials Media Codec Pack
  • K-Lite Codec Pack Full VLC
  • QuickTime Tried copying mpeg.dll codecs from 32 bit Windows 7 to Server and regsvr32'ing them, but get error
  • Tried copying *.AX filters from 32 bit Windows 7 to server and regsvr32'ing, but still get AVS error

  AVS Script :

  • video0 = DirectShowSource("video0.avi", fps=30, pixel_type="RGB24", Audio=false)
  • video1 = DirectShowSource("video1.avi", fps=30, pixel_type="RGB24", Audio=false)
  • Dissolve(video0, video1, 30)

  Command Line :

  • x264 test.avs -o test.mp4 —bframes 3 —ref 3 —vbv-maxrate 2500 —vbv-bufsize=25000 —level 40 —threads

  AVS Error :

  • avs [error] : "No combination of filters could be found to render the stream"

  Has anyone gotten this working on Windows Server ? If so what filters codecs or other setup do I need ?

  Thank you for the time.