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• Working way to make video from images in C#

  29 août 2011, par Jim Mischel

  Does anybody have a known reliable way to create a video from a series of image files ? Before you mod me down for not searching for the answer before posting the question, and before you fire off a simple message like "use FFMPEG," read the rest of this message.

  I'm trying to create a video, it doesn't matter too much what format as long as it's widely supported, from a series of images (.jpg, .bmp, etc.). My platform is Windows Server 2008, 64-bit. If I can make the video from within my C# program, that's great, but I'm not averse to writing a series of image files to a directory and then firing off an external program to make a video from those images.

  The only constraints are : it must work on my Windows Server 2008 system, and be scriptable. That is, no GUI programs that require operator intervention.

  I found a number of similar questions on StackOverflow, and have tried several of the solutions, all with varying degrees of frustration and none with anything like success.

  FFMPEG looks like a great program. Maybe it is, on Linux. The two Windows builds I downloaded are broken. Given this command line :

    ffmpeg -r 1 -f image2 -i jpeg\*.jpg video.avi

  One of the builds reads the images and then crashes due to data execution prevention. The other reads the first file and then spits out an error message that says "cannot find suitable codec for file jpeg/image2.jpg". Helpful, that. In any case, FFMPEG looks like a non-starter under Windows.

  One answer to a previous posting recommended Splicer . It looks like pretty good code. I compiled the samples and tried to run, but got some cryptic error message about a file not found. It looks like a COM class isn't registered. I suppose I need to install something (DirectShow, maybe, although I thought that was already installed ?). Depending on what's required, I might have a difficult time justifying its installation on a server. ("What ? Why do you need that on a server ?")

  Another answer suggested the AviFile library from Code Project. That looks simple enough : a wrapper around the Windows AviFile subsystem. Except that the AVI files the package creates appear to have all of the frames, but only the first frame shows when I play the AVI in Windows Media Player. Well, that and if you try to create a compressed video, the program throws an exception.

  So, I'm left wondering if there is a good, reliable way to do what I want : on a Windows system, create an AVI or other common video file format from a series of images, either through a .NET API or using an external program. Any help ?

• How to encode a stream of RGBA values to video ?

  20 septembre 2011, par Rob Oplawar

  More specifically :
  I have a sequence of 32 bit unsigned RGBA integers for pixels- e.g. 640 integers per row starting at the left pixel, 480 rows per frame starting at the top row, repeat for n frames. Is there an easy way to feed this to ffmpeg (or some other encoder) without first encoding it to a common image format ?

  I'm assuming ffmpeg is the best tool for me to use in this case, but I'm open to suggestions (the output video format doesn't matter too much).

  ---

  I know the documentation would enlighten me if I just knew the right keywords... In case I'm asking the wrong question, here's what I'm trying to do at the highest level :

  I have some Actionscript code that draws and animates on the display tree, and I've wrapped it in an AIR application that draws BitmapData frame-by-frame. AIR has proved to be woefully inefficient at directly encoding this output- the best I've managed is a few frames per second, and I need to render at least 15 fps, preferably more like 100 fps, which I get out of ffmpeg when I feed it PNG images (AIR can take 1+ seconds to encode one 640x480 png... appalling). Instead of encoding inside AIR I can send the raw byte data out to an encoder or to disk as fast as it's rendered.

  If you're wondering why I'm using Actionscript to render an animation or why it has to be encoded quickly, don't. Suffice it to say, the frames are computed at execution time (not stored as an animation in a .swf file, for example), I have a very large amount of video to create and limited time to do so, and using something other than Actionscript to produce the frames is not an option.

• Add SRT subtitle to video with ffmpeg

  3 juillet 2015, par jAckOdE

  I use ffmpeg to encode, and add subtitle to a video by following command

  $ ffmpeg -i hifi.avi -i hifi.srt -acodec libfaac -ar 48000 -ab 128k -ac 2 -vcodec libx264 -vpre ipod640 -s 480x240 -b 256k -scodec copy  hifi.m4v -newsubtitle

  Here is the output

  ffmpeg version 0.8.git, Copyright (c) 2000-2011 the FFmpeg developers
  
    built on Aug  4 2011 11:11:39 with gcc 4.5.2
  
    configuration: --extra-cflags=-I/usr/local/include --extra-ldflags=-L/usr/local/lib --disable-shared --enable-static --enable-gpl --enable-postproc --enable-pthreads --enable-ffplay --disable-ffserver --enable-memalign-hack --enable-nonfree --enable-libfaac --arch=x86 --enable-swscale --enable-libx264 --enable-avfilter --enable-debug=3
  
    libavutil    51. 11. 1 / 51. 11. 1
  
    libavcodec   53.  9. 1 / 53.  9. 1
  
    libavformat  53.  6. 0 / 53.  6. 0
  
    libavdevice  53.  2. 0 / 53.  2. 0
  
    libavfilter   2. 27. 5 /  2. 27. 5
  
    libswscale    2.  0. 0 /  2.  0. 0
  
    libpostproc  51.  2. 0 / 51.  2. 0
  
  Input #0, avi, from 'hifi.avi':
  
    Metadata:
  
      encoder         : VirtualDubMod 1.5.4.1 (build 2178/release)
  
      IAS1            : English
  
    Duration: 01:49:02.20, start: 0.000000, bitrate: 897 kb/s
  
      Stream #0.0: Video: mpeg4 (Simple Profile), yuv420p, 544x304 [SAR 1:1 DAR 34:19], 25 tbr, 25 tbn, 25 tbc
  
      Stream #0.1: Audio: mp3, 48000 Hz, stereo, s16, 32 kb/s
  
  [srt @ 0152c100] Estimating duration from bitrate, this may be inaccurate
  
  Input #1, srt, from 'hifi.srt':
  
    Duration: N/A, start: 56.080000, bitrate: N/A
  
      Stream #1.0: Subtitle: srt
  
  File 'hifi.m4v' already exists. Overwrite ? [y/N] y
  
  [buffer @ 02548920] w:544 h:304 pixfmt:yuv420p tb:1/1000000 sar:1/1 sws_param:
  
  [scale @ 02558ee0] w:544 h:304 fmt:yuv420p -> w:480 h:240 fmt:yuv420p flags:0x4
  
  [libx264 @ 02547f20] Default settings detected, using medium profile
  
  [libx264 @ 02547f20] using SAR=1/1
  
  [libx264 @ 02547f20] using cpu capabilities: MMX2 SSE2Fast SSSE3 FastShuffle SSE4.1 Cache64
  
  [libx264 @ 02547f20] profile High, level 3.0
  
  [libx264 @ 02547f20] 264 - core 115 - H.264/MPEG-4 AVC codec - Copyleft 2003-2011 - 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=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=0 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=abr mbtree=1 bitrate=256 ratetol=1.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 vbv_maxrate=10000 vbv_bufsize=10000 nal_hrd=none ip_ratio=1.40 aq=1:1.00
  
  Output #0, ipod, to 'hifi.m4v':
  
      Stream #0.0: Video: libx264, yuv420p, 480x240 [SAR 1:1 DAR 2:1], q=2-31, 256 kb/s, 90k tbn, 25 tbc
  
      Stream #0.1: Audio: libfaac, 48000 Hz, 2 channels, s16, 128 kb/s
  
      Stream #0.2: Subtitle: srt
  
      Stream #0.3: Subtitle: [0][0][0][0] / 0x0000, 64 kb/s
  
  Stream mapping:
  
    Stream #0.0 -> #0.0
  
    Stream #0.1 -> #0.1
  
    Stream #1.0 -> #0.2
  
    Stream #1.0 -> #0.3
  
  Encoder (codec id 0) not found for output stream #0.3

  can anyone tell what wrong with my command ??

  thanks,