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• configure : Use pkg-config for libdc1394 discovery

  22 février 2015, par Vittorio Giovara

  configure : Use pkg-config for libdc1394 discovery
  Since not all systems need the libraw1394 dependency, let pkg-config
  
  provide the list of libraries actually needed.
  The libdc1394-2.pc file has been included since version 2 (2008-01-05),
  
  so it should be safe to use.
  

  • [DBH] configure

• tag refuses to play mp4 video

  5 janvier 2015, par MightyPork

  I have a video I want to embed using the html5 video tag :

  • https://dl.dropboxusercontent.com/u/64454818/TMP/P6135199.MOV

  I’ve converted it using ffmpeg :

  ffmpeg -i P6135199.MOV -vcodec libx264 -acodec aac helios.mp4

  FFMPEG output :

  [libx264 @ 0x22ac340] using cpu capabilities : MMX2 SSE2Fast SSSE3 SSE4.2
  [libx264 @ 0x22ac340] profile High 4:2:2, level 1.2, 4:2:2 8-bit
  [libx264 @ 0x22ac340] 264 - core 142 r2455 021c0dc - H.264/MPEG-4 AVC codec - Copyleft 2003-2014 - http://www.videolan.org/x264.html - options : cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=6 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=15 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
  Output #0, mp4, to ’helios.mp4’ :
    Metadata :
      comment-eng : OLYMPUS DIGITAL CAMERA                           
      comment : OLYMPUS DIGITAL CAMERA                           
      encoder : Lavf56.15.102
      Stream #0:0(eng) : Video : h264 (libx264) ([33][0][0][0] / 0x0021), yuvj422p(pc), 320x240, q=-1—1, 15 fps, 15360 tbn, 15 tbc (default)
      Metadata :
        creation_time : 2008-06-13 10:47:16
        encoder : Lavc56.13.100 libx264
  Stream mapping :
    Stream #0:0 -> #0:0 (mjpeg (native) -> h264 (libx264))
  Press [q] to stop, [?] for help
  frame=  240 fps=124 q=-1.0 Lsize=     906kB time=00:00:15.86 bitrate= 467.7kbits/s    
  video:902kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead : 0.409100%
  [libx264 @ 0x22ac340] frame I:1     Avg QP:23.71  size :  7960
  [libx264 @ 0x22ac340] frame P:123   Avg QP:23.85  size :  5255
  [libx264 @ 0x22ac340] frame B:116   Avg QP:25.41  size :  2317
  [libx264 @ 0x22ac340] consecutive B-frames :  3.3% 96.7%  0.0%  0.0%
  [libx264 @ 0x22ac340] mb I  I16..4 : 15.7% 69.0% 15.3%
  [libx264 @ 0x22ac340] mb P  I16..4 :  2.2% 13.4%  0.8%  P16..4 : 43.8% 23.1% 14.0%  0.0%  0.0%    skip : 2.8%
  [libx264 @ 0x22ac340] mb B  I16..4 :  0.3%  1.3%  0.1%  B16..8 : 42.4%  9.9%  3.0%  direct:12.2%  skip:30.9%  L0:37.2% L1:38.2% BI:24.5%
  [libx264 @ 0x22ac340] 8x8 transform intra:80.8% inter:71.9%
  [libx264 @ 0x22ac340] coded y,uvDC,uvAC intra : 76.7% 96.8% 49.7% inter : 37.8% 60.9% 5.1%
  [libx264 @ 0x22ac340] i16 v,h,dc,p : 39%  4%  8% 49%
  [libx264 @ 0x22ac340] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu : 15% 14% 39%  6%  3%  4%  3%  6% 12%
  [libx264 @ 0x22ac340] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu : 25% 11% 18%  8%  7%  7%  8%  8%  8%
  [libx264 @ 0x22ac340] i8c dc,h,v,p : 63%  7% 20% 10%
  [libx264 @ 0x22ac340] Weighted P-Frames : Y:5.7% UV:0.8%
  [libx264 @ 0x22ac340] ref P L0 : 51.4% 18.3% 20.6%  9.3%  0.4%
  [libx264 @ 0x22ac340] ref B L0 : 80.8% 19.2%
  [libx264 @ 0x22ac340] kb/s:461.52
  

  And I try to embed it as follows :

  <video src="helios.mp4" controls="controls">Get a better browser!</video>

  However, Chrome doesn’t play the video, only offers to download it (same as it did before I converted the video). Firefox has the same problem.

  I’ve tested and other mp4 files (from my phone) play just fine.

  What’s the problem ? Did I convert it wrong ?

• ffmpeg and Red5 Issue : Increase in number of ffmpeg simultaneous streams to Red5 resulting in packet loss

  30 octobre 2014, par kajarigd

  I have a screen sharing app written in flex, using which one person can share his screen with another person via Red5 server (Version : 1.0.3). Platform is Windows Server 2008. Now, I want to load test this Red 5 server to find out maximum how many simultaneous screen sharing session it can allow, without any quality compromise. By quality I mean, speed of transmission and no data loss during transmission. I simulated the load using ffmpeg command.

  For this, instead of transmitting a live captured screen, I am transmitting (uploading) a FLV file stored in my local to the Red5 server using ffmpeg command. In the receiving client side, I am starting to download (transmitting) this same FLV file after 5 secs since the upload has started. This is working fine when I am running this test for less than 10 pairs of upstreaming-downstreaming sessions. But, when the number is increasing beyond 10, I am observing significant packet loss in transmission.

  Here are the commands I am running in a loop. The loop count is the number of streaming pairs.

  1. upstreaming : ffmpeg -re -i  -f flv -ar 22050 "rtmp://" -report
  2. downstreaming : ffmpeg -re -i "rtmp:// live=1"  -report

  The and are set in such a way, that in the downstream I will download the same uploaded file. "rtmp ://" are the same in both the cases. I am not doing the upstream in record mode, hence, no physical file is getting saved in the server side. When I am analyzing the file I received in the receiving client side, it is a poor quality video due to frame loss. Uploading and downloading machines are two different machines. I ran the test for many hours, repeating the same 10 simultaneous streaming sets. Each set is consistently giving the same results.

  What is puzzling me is, this is working fine without any packet loss for less that 10 simultaneous streaming. I searched about it in various forums, but none of the answers were applicable for this scenario. For a while I was thinking that Red5 has limited capacity, but I found many posts saying Red5 can easily scale up to take very big load. Does that mean, the problem is in my configuration ? I am not sure which are to focus on.

  An example log snippet :

  Lots of missing data at downstream side. For e.g. between frames 101 and 102 there is a difference of 25 sec. On replaying the video there is a stoppage for this much time.In this time gap all the frames are lost.

  frame=  101 fps=1.0 q=14.5 size=    2650kB time=00:01:41.00 bitrate= 214.9kbits/s
  
  frame=  102 fps=1.0 q=13.2 size=    2763kB time=00:02:06.00 bitrate= 179.6kbits/s

  Any help is appreciated !