Sur d’autres sites (6118)

• Extracting media duration in R

  27 septembre 2015, par Jason French

  I’m investigating the fastest way to extract film duration in R using ffprobe and the data.table package.

  Setup Example Source Media

  wget https://ia801403.us.archive.org/13/items/AboutBan1935/AboutBan1935_512kb.mp4
  
  mv AboutBan1935_512kb.mp4 one.mp4
  
  for file in two.mp4 three.mp4 four.mp4 five.mp4 ; do cp one.mp4 "$file" ; done

  Various Approaches

  library(data.table)
  
  library(parallel)
  
  
  
  # Get locations
  
  executables <- Sys.which(c('ffprobe', 'ffmpeg'))
  
  
  
  # Duration Function
  
  get_duration_parallel <- function(files){
  
    mclapply(X = files, FUN = function(file){
  
      ffprobe_duration <- paste(executables['ffprobe'],
  
                                " -v quiet -print_format compact=print_section=0:nokey=1:escape=csv -show_entries format=duration ",
  
                                '"', file, '"', sep = "")
  
  
  
      file_duration <- as.numeric(system(command = ffprobe_duration, intern = TRUE))
  
      return(file_duration)
  
    }, mc.cores = detectCores())
  
  }
  
  
  
  get_duration <- function(files){
  
    sapply(X = files, FUN = function(file){
  
      ffprobe_duration <- paste(executables['ffprobe'],
  
                                " -v quiet -print_format compact=print_section=0:nokey=1:escape=csv -show_entries format=duration ",
  
                                '"', file, '"', sep = "")
  
  
  
      file_duration <- as.numeric(system(command = ffprobe_duration, intern = TRUE))
  
      return(file_duration)
  
    })
  
  }
  
  
  
  # Example table
  
  dt <- data.table(Path = list.files(path = ".", pattern = "*.mp4$"))
  
  
  
  
  
  system.time(
  
    dt[, Seconds := get_duration_parallel(Path)]
  
  )
  
  # 9.667 seconds    
  
  
  
  system.time(
  
    dt[, Seconds := get_duration(Path)]
  
  )
  
  # 0.078 seconds

  Am I missing any obvious speed-ups ? Scanning a 500-file archive for ffprobe stats takes 5 minutes in testing.

• Stream to Azure Media Service from ffmpeg, stream can not be played

  24 juillet 2015, par Simon

  i try to send a stream from my RaspberryPI with debian wheezy to the AzureMediaService.
  I followed the instructions of this nice post.
  http://gtrifonov.com/2015/07/02/streaming-live-video-from-raspberrypi-to-azure-media-services/

  After a lot of trouble with the ffmpeg and libx264 builds i think i have it working now, to stream to the rtmp urls.

  INGESTURI="rtmp://office-klokklokmediastream.channel.mediaservices.windows.net:1935/live/3e541bc149754ebd975b95ec3583c949/mystream1"
  
  ffmpeg -framerate 30 -r 30 -s 640x480 -i /dev/video0 -vcodec libx264 -preset ultrafast -acodec libfaac -ab 48k -b:v 500k -maxrate 500k -bufsize 500k -r 30 -g 60 -keyint_min 60 -sc_threshold 0 -f flv $INGESTURI

  But when i try to watch the link in azure portal publish link or with the azure amsmediaplayer it tells me (i have reseted the channel already) :

  "The video could not be loaded, either because the server or network failed or because the format is not supported."

  The public stream url is :

  http://klokklokmediastream.streaming.mediaservices.windows.net/30c3920e-420a-4d33-8938-e79d0db240ff/c9fd3479-0d4b-4643-a3f9-5fd5831985d0.ism/Manifest

  In the linux shell i see the following output while streaming, looks for me as send stream is working :

  "root@raspberrypi:/home/pi/klokklok# ./azure_ffmpeg
  
  ffmpeg version N-73894-g830d3a0 Copyright (c) 2000-2015 the FFmpeg developers
  
    built with gcc 4.6 (Debian 4.6.3-14+rpi1)
  
    configuration: --arch=armel --target-os=linux --enable-gpl --enable-libx264 --enable-nonfree
  
    libavutil      54. 28.100 / 54. 28.100
  
    libavcodec     56. 50.101 / 56. 50.101
  
    libavformat    56. 40.101 / 56. 40.101
  
    libavdevice    56.  4.100 / 56.  4.100
  
    libavfilter     5. 25.100 /  5. 25.100
  
    libswscale      3.  1.101 /  3.  1.101
  
    libswresample   1.  2.101 /  1.  2.101
  
    libpostproc    53.  3.100 / 53.  3.100
  
  Input #0, video4linux2,v4l2, from '/dev/video0':
  
    Duration: N/A, start: -140462028.282167, bitrate: 110592 kb/s
  
      Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 640x480, 110592 kb/s, 30 fps, 30 tbr, 1000k tbn, 1000k tbc
  
  [libx264 @ 0x3321920] using cpu capabilities: none!
  
  [libx264 @ 0x3321920] profile Constrained Baseline, level 3.0
  
  [libx264 @ 0x3321920] 264 - core 146 r2538 121396c - H.264/MPEG-4 AVC codec - Copyleft 2003-2015 - http://www.videolan.org/x264.html - options: cabac=0 ref=1 deblock=0:0:0 analyse=0:0 me=dia subme=0 psy=1 psy_rd=1.00:0.00 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=0 threads=1 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=0 keyint=60 keyint_min=31 scenecut=0 intra_refresh=0 rc_lookahead=0 rc=cbr mbtree=0 bitrate=500 ratetol=1.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 vbv_maxrate=500 vbv_bufsize=500 nal_hrd=none filler=0 ip_ratio=1.40 aq=0
  
  Output #0, flv, to 'rtmp://office-klokklokmediastream.channel.mediaservices.windows.net:1935/live/3e501bc149754ebd975b95ec3583c949/mystream1':
  
    Metadata:
  
      encoder         : Lavf56.40.101
  
      Stream #0:0: Video: h264 (libx264) ([7][0][0][0] / 0x0007), yuv420p, 640x480, q=-1--1, 500 kb/s, 30 fps, 1k tbn, 30 tbc
  
      Metadata:
  
        encoder         : Lavc56.50.101 libx264
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (rawvideo (native) -> h264 (libx264))
  
  Press [q] to stop, [?] for help
  
  DTS 140462610481701, next:33333 st:0 invalid dropping
  
  PTS 140462610481701, next:33333 invalid dropping st:0
  
  DTS 140462610515017, next:66666 st:0 invalid dropping
  
  PTS 140462610515017, next:66666 invalid dropping st:0
  
  DTS 140462610548333, next:99999 st:0 invalid dropping
  
  PTS 140462610548333, next:99999 invalid dropping st:0
  
  frame=    4 fps=0.0 q=31.0 size=       7kB time=00:00:00.10 bitrate= 554.6kbits/DTS 140462610581650, next:133332 st:0 invalid dropping
  
  PTS 140462610581650, next:133332 invalid dropping st:0
  
  DTS 140462610614965, next:166665 st:0 invalid dropping
  
  PTS 140462610614965, next:166665 invalid dropping st:0
  
  frame=    6 fps=5.1 q=29.0 size=       9kB time=00:00:00.16 bitrate= 462.5kbits/DTS 140462610648281, next:199998 st:0 invalid dropping
  
  PTS 140462610648281, next:199998 invalid dropping st:0
  
  DTS 140462610681598, next:233331 st:0 invalid dropping
  
  PTS 140462610681598, next:233331 invalid dropping st:0
  
  DTS 140462610714914, next:266664 st:0 invalid dropping
  
  PTS 140462610714914, next:266664 invalid dropping st:0
  
  frame=   14 fps=4.6 q=23.0 size=      21kB time=00:00:00.43 bitrate= 396.0kbits/DTS 140462610914810, next:466662 st:0 invalid dropping
  
  PTS 140462610914810, next:466662 invalid dropping st:0
  
  [flv @ 0x3320ae0] Failed to update header with correct duration.
  
  [flv @ 0x3320ae0] Failed to update header with correct filesize.
  
  frame=   15 fps=3.9 q=22.0 Lsize=      25kB time=00:00:00.50 bitrate= 407.8kbits/s
  
  video:24kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 2.373589%
  
  [libx264 @ 0x3321920] frame I:1     Avg QP:31.00  size:  2777
  
  [libx264 @ 0x3321920] frame P:14    Avg QP:26.68  size:  1531
  
  [libx264 @ 0x3321920] mb I  I16..4: 100.0%  0.0%  0.0%
  
  [libx264 @ 0x3321920] mb P  I16..4: 12.4%  0.0%  0.0%  P16..4: 29.7%  0.0%  0.0%  0.0%  0.0%    skip:57.9%
  
  [libx264 @ 0x3321920] coded y,uvDC,uvAC intra: 6.3% 13.9% 0.5% inter: 5.7% 21.4% 0.1%
  
  [libx264 @ 0x3321920] i16 v,h,dc,p: 52% 17% 16% 14%
  
  [libx264 @ 0x3321920] i8c dc,h,v,p: 63% 14% 20%  3%
  
  [libx264 @ 0x3321920] kb/s:387.47
  
  Exiting normally, received signal 2.
  
  "

  I cant find a solution for that so thanks a lot for any advice.

• Azure Media service live streaming using raspberry pi 2

  29 juillet 2015, par emy virk

  I have tried to stream a video from my raspberry pi 2 using a webcam using the tutorial here http://gtrifonov.com/2015/07/02/streaming-live-video-from-raspberrypi-to-azure-media-services/.
  Using ffmpeg, I am running this in Ubuntu mate terminal :

  ffmpeg -framerate 30 -r 30 -s 640×480 -i /dev/video0 -vcodec libx264 -preset ultrafast -acodec libfaac -ab 48k -b:v 500k -maxrate 500k -bufsize 500k -r 30 -g 60 -keyint_min 60 -sc_threshold 0 -f flv $INGESTURI

  Now, to see the video is streaming I am using PLAY PREVIEW URL from the azure portal. It works, interrupted, at a very fast speed for about 5 second and than it stops with an error
  After that I try to play the video again and I can see the one that was streaming before the error and than it breaks again.
  From the Ubuntu mate I can tell the streaming is working fine : connection established and I can see the frames being sent.

  fps=7.9 q=28 bitrate = 500 kbits

  any idea why this is happening ?