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I'm building a NodeJS application that converts a static videofile to a streamable video which is being sent to a client (iPad or browser) on the fly (using the fluent-ffmpeg module).

Everything is set and all I need now is to configure ffmpeg correctly. But I'm having a lot of problems with ffmpeg. At first I built a flash stream (flv with lib264 codec which worked great, but of course does not work on the iPad).

With my current settings, I hear audio right away, but the picture starts a couple of seconds later. Then, my 30 second test file has been compressed to 3 seconds of high speed imagery.

How can I configure my ffmpeg so it will stream the mp4 correctly (in one pass through of course). It seems it's streaming raw h264, if that is the case how can I force the mp4 container. I thought I was doing that by using '-f mp4'

my correct settings are:

   '-crf 22','-c:v libx264','-f mp4','-movflags','faststart+frag_keyframe'

I've also tried:

 '-r 30','-crf 30','-analyzeduration 0','-probesize 1000','-rc_lookahead 0','-fflags nobuffer','-g 75','-ss 0','-threads 0','-vcodec libx264','-qcomp 0.6','-qmin 10','-qmax 51','-qdiff 4','-b:v 400k','-maxrate 400k','-bufsize 800k','-acodec mp3','-ab 192k','-ar 44100','-tune zerolatency','-f mp4','-movflags','faststart+frag_keyframe'

As you can see by the amount of options I've tried, I'm getting pretty desperate. I'm basically just running around in the dark.

I don't think it matters much but these are my request headers:

                    res.writeHead(200, { 
                        'Content-Range':'bytes '+start+'-'+end+'/'+stat.size,

FFmpeg log:

            file conversion error ffmpeg version N-52458-gaa96439 Copyright (c) 2000-2013 the FFmpeg developers
              built on Apr 24 2013 22:19:32 with gcc 4.8.0 (GCC)
              configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libcaca --enable-libfreetype --enable
            -libgsm --enable-libilbc --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwola
            me --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-libxvid --enable-zlib
              libavutil      52. 27.101 / 52. 27.101
              libavcodec     55.  6.100 / 55.  6.100
              libavformat    55.  3.100 / 55.  3.100
              libavdevice    55.  0.100 / 55.  0.100
              libavfilter     3. 60.101 /  3. 60.101
              libswscale      2.  2.100 /  2.  2.100
              libswresample   0. 17.102 /  0. 17.102
              libpostproc    52.  3.100 / 52.  3.100
            Input #0, avi, from 'C:/temp/avatar.avi':
                encoder         : Nandub v1.0rc2
              Duration: 00:01:09.78, start: 0.000000, bitrate: 1517 kb/s
                Stream #0:0: Video: msmpeg4v3 (DIV3 / 0x33564944), yuv420p, 640x352, 23.98 tbr, 23.98 tbn, 23.98 tbc
                Stream #0:1: Audio: mp3 (U[0][0][0] / 0x0055), 48000 Hz, stereo, s16p, 222 kb/s
            [libx264 @ 0218d480] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
            [libx264 @ 0218d480] profile High, level 3.0
            [libx264 @ 0218d480] 264 - core 130 r2274 c832fe9 - H.264/MPEG-4 AVC codec - Copyleft 2003-2013 - - 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=12 lookahead_threads=2 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 w
            eightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=23 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=22.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
            Output #0, mp4, to 'pipe:1':
                encoder         : Lavf55.3.100
                Stream #0:0: Video: h264 ([33][0][0][0] / 0x0021), yuv420p, 640x352, q=-1--1, 11988 tbn, 23.98 tbc
                Stream #0:1: Audio: aac ([64][0][0][0] / 0x0040), 48000 Hz, stereo, s16, 128 kb/s
            Stream mapping:
              Stream #0:0 -> #0:0 (msmpeg4 -> libx264)
              Stream #0:1 -> #0:1 (mp3 -> libvo_aacenc)
            Press [q] to stop, [?] for help
            frame=  103 fps=0.0 q=27.0 size=       0kB time=00:00:04.70 bitrate=   0.1kbits/s
            frame=  162 fps=161 q=27.0 size=     278kB time=00:00:07.15 bitrate= 317.9kbits/s
            frame=  214 fps=141 q=27.0 size=     463kB time=00:00:09.33 bitrate= 406.3kbits/s
            frame=  277 fps=137 q=27.0 size=     673kB time=00:00:11.95 bitrate= 461.3kbits/s
            frame=  334 fps=132 q=27.0 size=     826kB time=00:00:14.32 bitrate= 472.5kbits/s
            frame=  386 fps=127 q=27.0 size=    1061kB time=00:00:16.52 bitrate= 526.2kbits/s
            frame=  428 fps=120 q=27.0 size=    1061kB time=00:00:18.27 bitrate= 475.9kbits/s
            frame=  472 fps=116 q=27.0 size=    1061kB time=00:00:20.08 bitrate= 432.9kbits/s
            frame=  525 fps=115 q=27.0 size=    1562kB time=00:00:22.30 bitrate= 573.7kbits/s
            frame=  589 fps=116 q=27.0 size=    1804kB time=00:00:24.99 bitrate= 591.4kbits/s
            frame=  690 fps=124 q=27.0 size=    1804kB time=00:00:29.19 bitrate= 506.2kbits/s
            frame=  827 fps=136 q=27.0 size=    2191kB time=00:00:34.91 bitrate= 514.1kbits/s
            frame=  921 fps=140 q=27.0 size=    2540kB time=00:00:38.81 bitrate= 536.1kbits/s
            frame= 1015 fps=143 q=27.0 size=    2540kB time=00:00:42.74 bitrate= 486.9kbits/s
            frame= 1124 fps=148 q=27.0 size=    3531kB time=00:00:47.30 bitrate= 611.5kbits/s
            frame= 1248 fps=154 q=27.0 size=    3727kB time=00:00:52.46 bitrate= 581.9kbits/s
            frame= 1371 fps=160 q=27.0 size=    4251kB time=00:00:57.58 bitrate= 604.7kbits/s
            frame= 1516 fps=167 q=27.0 size=    4684kB time=00:01:03.62 bitrate= 603.0kbits/s
            frame= 1632 fps=170 q=27.0 size=    4932kB time=00:01:08.46 bitrate= 590.1kbits/s
            frame= 1673 fps=167 q=2686559.0 Lsize=    5507kB time=00:01:09.76 bitrate= 646.6kbits/s

            video:4385kB audio:1091kB subtitle:0 global headers:0kB muxing overhead 0.582195%
            [libx264 @ 0218d480] frame I:17    Avg QP:18.90  size: 11501
            [libx264 @ 0218d480] frame P:1467  Avg QP:21.41  size:  2825
            [libx264 @ 0218d480] frame B:189   Avg QP:24.42  size:   788
            [libx264 @ 0218d480] consecutive B-frames: 84.5%  1.0%  1.4% 13.2%
            [libx264 @ 0218d480] mb I  I16..4: 21.5% 75.6%  2.9%
            [libx264 @ 0218d480] mb P  I16..4:  1.0%  2.8%  0.2%  P16..4: 39.6% 13.7%  8.2%  0.0%  0.0%    skip:34.6%
            [libx264 @ 0218d480] mb B  I16..4:  0.1%  0.3%  0.1%  B16..8: 37.3%  2.6%  0.4%  direct: 0.8%  skip:58.4%  L0:44.0% L1:51.7% BI: 4.3%
            [libx264 @ 0218d480] 8x8 transform intra:70.8% inter:82.9%
            [libx264 @ 0218d480] coded y,uvDC,uvAC intra: 58.7% 53.9% 12.8% inter: 20.2% 19.7% 0.4%
            [libx264 @ 0218d480] i16 v,h,dc,p: 62% 16%  9% 13%
            [libx264 @ 0218d480] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 27% 14% 30%  3%  5%  6%  4%  5%  4%
            [libx264 @ 0218d480] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 34% 13% 11%  4% 10% 11%  7%  6%  3%
            [libx264 @ 0218d480] i8c dc,h,v,p: 44% 19% 33%  4%
            [libx264 @ 0218d480] Weighted P-Frames: Y:0.1% UV:0.0%
            [libx264 @ 0218d480] ref P L0: 69.0% 16.7% 10.2%  4.0%  0.0%
            [libx264 @ 0218d480] ref B L0: 86.1% 10.0%  3.9%
            [libx264 @ 0218d480] ref B L1: 92.9%  7.1%
            [libx264 @ 0218d480] kb/s:514.67

My exact nodejs command with test cases I've used (which are commented out):

                            , proc = new ffmpeg({ 
                                source: movie, 
                                nolog: true, 
                            .addOptions(['-crf 22','-c:v libx264','-f mp4','-movflags','faststart+frag_keyframe'])
                            //.addOptions(['-threads 0', '-i_qfactor 0.71', '-qcomp 0.6', '-qmin 10', '-qmax 63', '-qdiff 4', '-trellis 0', '-vcodec libx264', '-s 640x360', '-b:v 1000k', '-b:a 56k','-ar 22050','-f mp4','-movflags','faststart+frag_keyframe'])
                            //.addOptions(['-r 30','-crf 30','-analyzeduration 0','-probesize 1000','-rc_lookahead 0','-fflags nobuffer','-g 75','-ss 0','-threads 0','-vcodec libx264','-qcomp 0.6','-qmin 10','-qmax 51','-qdiff 4','-b:v 400k','-maxrate 400k','-bufsize 800k','-acodec mp3','-ab 192k','-ar 44100','-tune zerolatency',metaDuration,tDuration,'-f mp4','-movflags','faststart+frag_keyframe'])
                            .writeToStream(res, function(retcode, error){
                                if (!error){
                                    console.log('file has been converted succesfully',retcode .green);
                                    console.log('file conversion error',error .red);

My frontend player is a basic HTML5 player with videoJS on top (for theming and control-ability).

      <video id="player" class="video-js vjs-default-skin" controls preload="both" width="100%" height="100%"><source src="'+url+'" type="video/mp4"></video>
share|improve this question
Please show the exact command you're using (not just the parameters), and the full, uncut ffmpeg console output. Thanks. – slhck Aug 28 '13 at 13:27
Sorry about the cross post. I've edited my post to provide you more details. Thanks for your time! – jansmolders86 Aug 28 '13 at 13:33

Did you check that the frame rate of the original video matches your other settings? Also the source video if it has 48kHz to start with, when you go to encode could cause the shift you're seeing when you try to make the output 44.1kHz. Make sure the file going in is also 44.1

share|improve this answer

The answer might be a little bit late, but did you try using the '-re' option?

If you don't use it, it tries to stream the video to the destination as fast as possible.

With -re you read the file at its native frame rate and thus it also gets transmitted at the playback speed of the video.

share|improve this answer

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