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    10 avril 2011

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    13 mars 2010, par

    Pour des raisons de compatibilité générale du plugin de gestion de mutualisations avec les fonctions originales de SPIP, les statuts des instances sont les mêmes que pour tout autre objets (articles...), seuls leurs noms dans l’interface change quelque peu.
    Les différents statuts possibles sont : prepa (demandé) qui correspond à une instance demandée par un utilisateur. Si le site a déjà été créé par le passé, il est passé en mode désactivé. publie (validé) qui correspond à une instance validée par un (...)

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  • No audio encoded with ffmpeg using webm/libvorbis

    15 mars 2013, par Craig Lillard

    Having issues getting audio to encode to webm. Tried many different methods and it just ain't happenin. The commands are printed below before each pass.

    I have tried moving the audio commands around, trying different bitrates, different audio commands and have tried it on a couple of different files as well that both have audio.

    Encoding these files to MP4 using x264 causes no problems and works just fine and the audio plays, so it appears to be an issue just with webm. As you can see below, it is a 2-pass encode.

    Thanks for any help you can provide !

    Craig

    Webm LG PASS 1...........................




       webm_pass1: /usr/bin/ffmpeg -i /home/thedirectory/video613268.mov  -codec:v libvpx -quality good -vf 'scale=640:360 [scaled];movie=/home/thedirectory/watermarks/w640X360.png [logo];[scaled][logo] overlay' -cpu-used 0 -b:v 500k -aspect 16:9 -qmin 10 -qmax 42 -maxrate:v 500k -bufsize:v 1000k -r:v 25/1 -force_fps -threads 0 -an -acodec libvorbis -ac 2 -ab 96k -ar 44100 -pass 1 -f webm -y /dev/null



       ffmpeg version 0.10.2 Copyright (c) 2000-2012 the FFmpeg developers
         built on Mar 11 2013 14:48:26 with gcc 4.6.2 20111027 (Red Hat 4.6.2-2)
         configuration: --prefix=/usr --libdir=/usr/lib64 --shlibdir=/usr/lib64 --mandir=/usr/share/man --incdir=/usr/include --disable-avisynth --extra-cflags='-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m64 -mtune=generic -fPIC' --enable-avfilter --enable-libfaac --enable-libgsm --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libx264 --enable-gpl --enable-nonfree --enable-postproc --enable-pthreads --enable-shared --enable-swscale --enable-vdpau --enable-version3 --enable-x11grab --enable-libvorbis --enable-libvpx
         libavutil      51. 35.100 / 51. 35.100
         libavcodec     53. 61.100 / 53. 61.100
         libavformat    53. 32.100 / 53. 32.100
         libavdevice    53.  4.100 / 53.  4.100
         libavfilter     2. 61.100 /  2. 61.100
         libswscale      2.  1.100 /  2.  1.100
         libswresample   0.  6.100 /  0.  6.100
         libpostproc    52.  0.100 / 52.  0.100
       Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/home/thedirectory/video613268.mov':
         Metadata:
           major_brand     : qt  
           minor_version   : 537199360
           compatible_brands: qt  
           creation_time   : 2013-02-23 20:04:32
         Duration: 00:00:21.02, start: 0.000000, bitrate: 114326 kb/s
           Stream #0:0(eng): Video: mjpeg (jpeg / 0x6765706A), yuvj422p, 1920x1080 [SAR 72:72 DAR 16:9], 112786 kb/s, 29.97 fps, 29.97 tbr, 2997 tbn, 2997 tbc
           Metadata:
             creation_time   : 2013-02-23 20:04:32
             handler_name    : ?Gestionnaire d?alias Apple
           Stream #0:1(eng): Audio: pcm_s16be (twos / 0x736F7774), 48000 Hz, 2 channels, s16, 1536 kb/s
           Metadata:
             creation_time   : 2013-02-23 20:04:32
             handler_name    : ?Gestionnaire d?alias Apple
       Incompatible pixel format 'yuvj422p' for codec 'libvpx', auto-selecting format 'yuv420p'
       [buffer @ 0x1f675a0] w:1920 h:1080 pixfmt:yuvj422p tb:1/1000000 sar:1/1 sws_param:
       [movie @ 0x1f799c0] seek_point:0 format_name:(null) file_name:/home/thedirectory/watermarks/w640X360.png stream_index:0
       [overlay @ 0x1f7c2c0] auto-inserting filter 'auto-inserted scale 0' between the filter 'Parsed_movie_1' and the filter 'Parsed_overlay_2'
       [scale @ 0x1f78d40] w:1920 h:1080 fmt:yuvj422p -> w:640 h:360 fmt:yuv420p flags:0x4
       [scale @ 0x1f7cde0] w:640 h:360 fmt:rgba -> w:640 h:360 fmt:yuva420p flags:0x4
       [overlay @ 0x1f7c2c0] main w:640 h:360 fmt:yuv420p overlay x:0 y:0 w:640 h:360 fmt:yuva420p
       [overlay @ 0x1f7c2c0] main_tb:1/1000000 overlay_tb:1/25 -> tb:1/1000000 exact:1
       [libvpx @ 0x1f77ce0] v1.0.0
       Output #0, webm, to '/dev/null':
         Metadata:
           major_brand     : qt  
           minor_version   : 537199360
           compatible_brands: qt  
           creation_time   : 2013-02-23 20:04:32
           encoder         : Lavf53.32.100
           Stream #0:0(eng): Video: vp8, yuv420p, 640x360 [SAR 1:1 DAR 16:9], q=10-42, pass 1, 500 kb/s, 1k tbn, 25 tbc
           Metadata:
             creation_time   : 2013-02-23 20:04:32
             handler_name    : ?Gestionnaire d?alias Apple
       Stream mapping:
         Stream #0:0 -> #0:0 (mjpeg -> libvpx)
       Press [q] to stop, [?] for help
       frame=  527 fps= 21 q=0.0 Lsize=       0kB time=00:00:00.00 bitrate=   0.0kbits/s dup=0 drop=103    
       video:0kB audio:0kB global headers:0kB muxing overhead -nan%
       Output file is empty, nothing was encoded (check -ss / -t / -frames parameters if used)
       Webm LG PASS 2.......................




       webm_pass2: /usr/bin/ffmpeg -i /home/thedirectory/video613268.mov -codec:v libvpx -quality good -vf 'scale=640:360 [scaled];movie=/home/thedirectory/watermarks/w640X360.png [logo];[scaled][logo] overlay' -cpu-used 0 -b:v 500k  -aspect 16:9  -qmin 10 -qmax 42 -maxrate:v 500k -bufsize:v 1000k -r:v 24/1 -force_fps -threads 0 -an -acodec libvorbis -ac 2 -ab 96k -ar 44100 -pass 2 -f webm -y /media/amazons3/webmlg/video613268.mov.webm



       ffmpeg version 0.10.2 Copyright (c) 2000-2012 the FFmpeg developers
         built on Mar 11 2013 14:48:26 with gcc 4.6.2 20111027 (Red Hat 4.6.2-2)
         configuration: --prefix=/usr --libdir=/usr/lib64 --shlibdir=/usr/lib64 --mandir=/usr/share/man --incdir=/usr/include --disable-avisynth --extra-cflags='-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m64 -mtune=generic -fPIC' --enable-avfilter --enable-libfaac --enable-libgsm --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libx264 --enable-gpl --enable-nonfree --enable-postproc --enable-pthreads --enable-shared --enable-swscale --enable-vdpau --enable-version3 --enable-x11grab --enable-libvorbis --enable-libvpx
         libavutil      51. 35.100 / 51. 35.100
         libavcodec     53. 61.100 / 53. 61.100
         libavformat    53. 32.100 / 53. 32.100
         libavdevice    53.  4.100 / 53.  4.100
         libavfilter     2. 61.100 /  2. 61.100
         libswscale      2.  1.100 /  2.  1.100
         libswresample   0.  6.100 /  0.  6.100
         libpostproc    52.  0.100 / 52.  0.100
       Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/home/thedirectory/video613268.mov':
         Metadata:
           major_brand     : qt  
           minor_version   : 537199360
           compatible_brands: qt  
           creation_time   : 2013-02-23 20:04:32
         Duration: 00:00:21.02, start: 0.000000, bitrate: 114326 kb/s
           Stream #0:0(eng): Video: mjpeg (jpeg / 0x6765706A), yuvj422p, 1920x1080 [SAR 72:72 DAR 16:9], 112786 kb/s, 29.97 fps, 29.97 tbr, 2997 tbn, 2997 tbc
           Metadata:
             creation_time   : 2013-02-23 20:04:32
             handler_name    : ?Gestionnaire d?alias Apple
           Stream #0:1(eng): Audio: pcm_s16be (twos / 0x736F7774), 48000 Hz, 2 channels, s16, 1536 kb/s
           Metadata:
             creation_time   : 2013-02-23 20:04:32
             handler_name    : ?Gestionnaire d?alias Apple
       Incompatible pixel format 'yuvj422p' for codec 'libvpx', auto-selecting format 'yuv420p'
       [buffer @ 0x1f2a5a0] w:1920 h:1080 pixfmt:yuvj422p tb:1/1000000 sar:1/1 sws_param:
       [movie @ 0x1f3bec0] seek_point:0 format_name:(null) file_name:/home/thedirectory/watermarks/w640X360.png stream_index:0
       [overlay @ 0x1f3f2c0] auto-inserting filter 'auto-inserted scale 0' between the filter 'Parsed_movie_1' and the filter 'Parsed_overlay_2'
       [scale @ 0x1f3c8a0] w:1920 h:1080 fmt:yuvj422p -> w:640 h:360 fmt:yuv420p flags:0x4
       [scale @ 0x1f3fde0] w:640 h:360 fmt:rgba -> w:640 h:360 fmt:yuva420p flags:0x4
       [overlay @ 0x1f3f2c0] main w:640 h:360 fmt:yuv420p overlay x:0 y:0 w:640 h:360 fmt:yuva420p
       [overlay @ 0x1f3f2c0] main_tb:1/1000000 overlay_tb:1/25 -> tb:1/1000000 exact:1
       [libvpx @ 0x1f3ace0] v1.0.0
       Output #0, webm, to '/media/amazons3/webmlg/video613268.mov.webm':
         Metadata:
           major_brand     : qt  
           minor_version   : 537199360
           compatible_brands: qt  
           creation_time   : 2013-02-23 20:04:32
           encoder         : Lavf53.32.100
           Stream #0:0(eng): Video: vp8, yuv420p, 640x360 [SAR 1:1 DAR 16:9], q=10-42, pass 2, 500 kb/s, 1k tbn, 24 tbc
           Metadata:
             creation_time   : 2013-02-23 20:04:32
             handler_name    : ?Gestionnaire d?alias Apple
       Stream mapping:
         Stream #0:0 -> #0:0 (mjpeg -> libvpx)
       Press [q] to stop, [?] for help
       frame=  506 fps=  7 q=0.0 Lsize=    1610kB time=00:00:21.08 bitrate= 625.8kbits/s dup=0 drop=124    
       video:1389kB audio:0kB global headers:0kB muxing overhead 15.952140%
  • H.264 muxed to MP4 using libavformat not playing back

    14 mai 2015, par Brad Mitchell

    I am trying to mux H.264 data into a MP4 file. There appear to be no errors in saving this H.264 Annex B data out to an MP4 file, but the file fails to playback.

    I’ve done a binary comparison on the files and the issue seems to be somewhere in what is being written to the footer (trailer) of the MP4 file.

    I suspect it has to be something with the way the stream is being created or something.

    Init :

    AVOutputFormat* fmt = av_guess_format( 0, "out.mp4", 0 );
    oc = avformat_alloc_context();
    oc->oformat = fmt;
    strcpy(oc->filename, filename);

    Part of this prototype app I have is creating a png file for each IFrame. So when the first IFrame is encountered, I create the video stream and write the av header etc :

    void addVideoStream(AVCodecContext* decoder)
    {
       videoStream = av_new_stream(oc, 0);
       if (!videoStream)
       {
            cout << "ERROR creating video stream" << endl;
            return;        
       }
       vi = videoStream->index;    
       videoContext = videoStream->codec;      
       videoContext->codec_type = AVMEDIA_TYPE_VIDEO;
       videoContext->codec_id = decoder->codec_id;
       videoContext->bit_rate = 512000;
       videoContext->width = decoder->width;
       videoContext->height = decoder->height;
       videoContext->time_base.den = 25;
       videoContext->time_base.num = 1;    
       videoContext->gop_size = decoder->gop_size;
       videoContext->pix_fmt = decoder->pix_fmt;      

       if (oc->oformat->flags & AVFMT_GLOBALHEADER)
           videoContext->flags |= CODEC_FLAG_GLOBAL_HEADER;

       av_dump_format(oc, 0, filename, 1);

       if (!(oc->oformat->flags & AVFMT_NOFILE))
       {
           if (avio_open(&oc->pb, filename, AVIO_FLAG_WRITE) < 0) {
           cout << "Error opening file" << endl;
       }
       avformat_write_header(oc, NULL);
    }

    I write packets out :

    unsigned char* data = block->getData();
    unsigned char videoFrameType = data[4];
    int dataLen = block->getDataLen();

    // store pps
    if (videoFrameType == 0x68)
    {
       if (ppsFrame != NULL)
       {
           delete ppsFrame; ppsFrameLength = 0; ppsFrame = NULL;
       }
       ppsFrameLength = block->getDataLen();
       ppsFrame = new unsigned char[ppsFrameLength];
       memcpy(ppsFrame, block->getData(), ppsFrameLength);
    }
    else if (videoFrameType == 0x67)
    {
       // sps
       if (spsFrame != NULL)
       {
           delete spsFrame; spsFrameLength = 0; spsFrame = NULL;
    }
       spsFrameLength = block->getDataLen();
       spsFrame = new unsigned char[spsFrameLength];
       memcpy(spsFrame, block->getData(), spsFrameLength);                
    }                                          

    if (videoFrameType == 0x65 || videoFrameType == 0x41)
    {
       videoFrameNumber++;
    }
    if (videoFrameType == 0x65)
    {
       decodeIFrame(videoFrameNumber, spsFrame, spsFrameLength, ppsFrame, ppsFrameLength, data, dataLen);
    }

    if (videoStream != NULL)
    {
       AVPacket pkt = { 0 };
       av_init_packet(&pkt);
       pkt.stream_index = vi;
       pkt.flags = 0;                      
       pkt.pts = pkt.dts = 0;                                  

       if (videoFrameType == 0x65)
       {
           // combine the SPS PPS & I frames together
           pkt.flags |= AV_PKT_FLAG_KEY;                                                  
           unsigned char* videoFrame = new unsigned char[spsFrameLength+ppsFrameLength+dataLen];
           memcpy(videoFrame, spsFrame, spsFrameLength);
           memcpy(&videoFrame[spsFrameLength], ppsFrame, ppsFrameLength);
           memcpy(&videoFrame[spsFrameLength+ppsFrameLength], data, dataLen);

           // overwrite the start code (00 00 00 01 with a 32-bit length)
           setLength(videoFrame, spsFrameLength-4);
           setLength(&videoFrame[spsFrameLength], ppsFrameLength-4);
           setLength(&videoFrame[spsFrameLength+ppsFrameLength], dataLen-4);
           pkt.size = dataLen + spsFrameLength + ppsFrameLength;
           pkt.data = videoFrame;
           av_interleaved_write_frame(oc, &pkt);
           delete videoFrame; videoFrame = NULL;
       }
       else if (videoFrameType != 0x67 && videoFrameType != 0x68)
       {  
           // Send other frames except pps & sps which are caught and stored                  
           pkt.size = dataLen;
           pkt.data = data;
           setLength(data, dataLen-4);                    
           av_interleaved_write_frame(oc, &pkt);
       }

    Finally to close the file off :

    av_write_trailer(oc);
    int i = 0;
    for (i = 0; i < oc->nb_streams; i++)
    {
       av_freep(&oc->streams[i]->codec);
       av_freep(&oc->streams[i]);      
    }

    if (!(oc->oformat->flags & AVFMT_NOFILE))
    {
       avio_close(oc->pb);
    }
    av_free(oc);

    If I take the H.264 data alone and convert it :

    ffmpeg -i recording.h264 -vcodec copy recording.mp4

    All but the "footer" of the files are the same.

    Output from my program :
    readrec recording.tcp out.mp4
    ** START * 01-03-2013 14:26:01 180000
    Output #0, mp4, to ’out.mp4’ :
    Stream #0:0 : Video : h264, yuv420p, 352x288, q=2-31, 512 kb/s, 90k tbn, 25 tbc
    * END ** 01-03-2013 14:27:01 102000
    Wrote 1499 video frames.

    If I try to convert using ffmpeg the MP4 file created using CODE :

    ffmpeg -i out.mp4 -vcodec copy out2.mp4
    ffmpeg version 0.11.1 Copyright (c) 2000-2012 the FFmpeg developers
         built on Mar  7 2013 12:49:22 with suncc 0x5110
         configuration: --extra-cflags=-KPIC -g --disable-mmx
         --disable-protocol=udp --disable-encoder=nellymoser --cc=cc --cxx=CC
    libavutil      51. 54.100 / 51. 54.100
    libavcodec     54. 23.100 / 54. 23.100
    libavformat    54.  6.100 / 54.  6.100
    libavdevice    54.  0.100 / 54.  0.100
    libavfilter     2. 77.100 /  2. 77.100
    libswscale      2.  1.100 /  2.  1.100
    libswresample   0. 15.100 /  0. 15.100
    h264 @ 12eaac0] no frame!
       Last message repeated 1 times
    [h264 @ 12eaac0] slice type too large (0) at 0 0
    [h264 @ 12eaac0] decode_slice_header error
    [h264 @ 12eaac0] no frame!
       Last message repeated 23 times
    [h264 @ 12eaac0] slice type too large (0) at 0 0
    [h264 @ 12eaac0] decode_slice_header error
    [h264 @ 12eaac0] no frame!
       Last message repeated 74 times
    [h264 @ 12eaac0] slice type too large (0) at 0 0
    [h264 @ 12eaac0] decode_slice_header error
    [h264 @ 12eaac0] no frame!
       Last message repeated 64 times
    [h264 @ 12eaac0] slice type too large (0) at 0 0
    [h264 @ 12eaac0] decode_slice_header error
    [h264 @ 12eaac0] no frame!
       Last message repeated 34 times
    [h264 @ 12eaac0] slice type too large (0) at 0 0
    [h264 @ 12eaac0] decode_slice_header error
    [h264 @ 12eaac0] no frame!
       Last message repeated 49 times
    [h264 @ 12eaac0] slice type too large (0) at 0 0
    [h264 @ 12eaac0] decode_slice_header error
    [h264 @ 12eaac0] no frame!
       Last message repeated 24 times
    [h264 @ 12eaac0] Partitioned H.264 support is incomplete
    [h264 @ 12eaac0] no frame!
       Last message repeated 23 times
    [h264 @ 12eaac0] sps_id out of range
    [h264 @ 12eaac0] no frame!
       Last message repeated 148 times
    [h264 @ 12eaac0] sps_id (32) out of range
       Last message repeated 1 times
    [h264 @ 12eaac0] no frame!
       Last message repeated 33 times
    [h264 @ 12eaac0] slice type too large (0) at 0 0
    [h264 @ 12eaac0] decode_slice_header error
    [h264 @ 12eaac0] no frame!
       Last message repeated 128 times
    [h264 @ 12eaac0] sps_id (32) out of range
       Last message repeated 1 times
    [h264 @ 12eaac0] no frame!
       Last message repeated 3 times
    [h264 @ 12eaac0] slice type too large (0) at 0 0
    [h264 @ 12eaac0] decode_slice_header error
    [h264 @ 12eaac0] no frame!
       Last message repeated 3 times
    [h264 @ 12eaac0] slice type too large (0) at 0 0
    [h264 @ 12eaac0] decode_slice_header error
    [h264 @ 12eaac0] no frame!
       Last message repeated 309 times
    [h264 @ 12eaac0] sps_id (32) out of range
       Last message repeated 1 times
    [h264 @ 12eaac0] no frame!
       Last message repeated 192 times
    [h264 @ 12eaac0] Partitioned H.264 support is incomplete
    [h264 @ 12eaac0] no frame!
       Last message repeated 73 times
    [h264 @ 12eaac0] sps_id (32) out of range
       Last message repeated 1 times
    [h264 @ 12eaac0] no frame!
       Last message repeated 99 times
    [h264 @ 12eaac0] sps_id (32) out of range
       Last message repeated 1 times
    [h264 @ 12eaac0] no frame!
       Last message repeated 197 times
    [mov,mp4,m4a,3gp,3g2,mj2 @ 12e3100] decoding for stream 0 failed
    [mov,mp4,m4a,3gp,3g2,mj2 @ 12e3100] Could not find codec parameters
    (Video: h264 (avc1 / 0x31637661), 393539 kb/s)
    out.mp4: could not find codec parameters

    I really do not know where the issue is, except it has to be something to do with the way the streams are being set up. I’ve looked at bits of code from where other people are doing a similar thing, and tried to use this advice in setting up the streams, but to no avail !


    The final code which gave me a H.264/AAC muxed (synced) file is as follows. First a bit of background information. The data is coming from an IP camera. The data is presented via a 3rd party API as video/audio packets. The video packets are presented as the RTP payload data (no header) and consist of NALU’s that are reconstructed and converted to H.264 video in Annex B format. AAC audio is presented as raw AAC and is converted to adts format to enable playback. These packets have been put into a bitstream format that allows the transmission of the timestamp (64 bit milliseconds since Jan 1 1970) along with a few other things.

    This is more or less a prototype and is not clean in any respects. It probably leaks bad. I do however, hope this helps anyone else out trying to achieve something similar to what I am.

    Globals :

    AVFormatContext* oc = NULL;
    AVCodecContext* videoContext = NULL;
    AVStream* videoStream = NULL;
    AVCodecContext* audioContext = NULL;
    AVStream* audioStream = NULL;
    AVCodec* videoCodec = NULL;
    AVCodec* audioCodec = NULL;
    int vi = 0;  // Video stream
    int ai = 1;  // Audio stream

    uint64_t firstVideoTimeStamp = 0;
    uint64_t firstAudioTimeStamp = 0;
    int audioStartOffset = 0;

    char* filename = NULL;

    Boolean first = TRUE;

    int videoFrameNumber = 0;
    int audioFrameNumber = 0;

    Main :

    int main(int argc, char* argv[])
    {
       if (argc != 3)
       {  
           cout &lt;&lt; argv[0] &lt;&lt; " <stream playback="playback" file="file"> <output mp4="mp4" file="file">" &lt;&lt; endl;
           return 0;
       }
       char* input_stream_file = argv[1];
       filename = argv[2];

       av_register_all();    

       fstream inFile;
       inFile.open(input_stream_file, ios::in);

       // Used to store the latest pps &amp; sps frames
       unsigned char* ppsFrame = NULL;
       int ppsFrameLength = 0;
       unsigned char* spsFrame = NULL;
       int spsFrameLength = 0;

       // Setup MP4 output file
       AVOutputFormat* fmt = av_guess_format( 0, filename, 0 );
       oc = avformat_alloc_context();
       oc->oformat = fmt;
       strcpy(oc->filename, filename);

       // Setup the bitstream filter for AAC in adts format.  Could probably also achieve
       // this by stripping the first 7 bytes!
       AVBitStreamFilterContext* bsfc = av_bitstream_filter_init("aac_adtstoasc");
       if (!bsfc)
       {      
           cout &lt;&lt; "Error creating adtstoasc filter" &lt;&lt; endl;
           return -1;
       }

       while (inFile.good())
       {
           TcpAVDataBlock* block = new TcpAVDataBlock();
           block->readStruct(inFile);
           DateTime dt = block->getTimestampAsDateTime();
           switch (block->getPacketType())
           {
               case TCP_PACKET_H264:
               {      
                   if (firstVideoTimeStamp == 0)
                       firstVideoTimeStamp = block->getTimeStamp();
                   unsigned char* data = block->getData();
                   unsigned char videoFrameType = data[4];
                   int dataLen = block->getDataLen();

                   // pps
                   if (videoFrameType == 0x68)
                   {
                       if (ppsFrame != NULL)
                       {
                           delete ppsFrame; ppsFrameLength = 0;
                           ppsFrame = NULL;
                       }
                       ppsFrameLength = block->getDataLen();
                       ppsFrame = new unsigned char[ppsFrameLength];
                       memcpy(ppsFrame, block->getData(), ppsFrameLength);
                   }
                   else if (videoFrameType == 0x67)
                   {
                       // sps
                       if (spsFrame != NULL)
                       {
                           delete spsFrame; spsFrameLength = 0;
                           spsFrame = NULL;
                       }
                       spsFrameLength = block->getDataLen();
                       spsFrame = new unsigned char[spsFrameLength];
                       memcpy(spsFrame, block->getData(), spsFrameLength);                  
                   }                                          

                   if (videoFrameType == 0x65 || videoFrameType == 0x41)
                   {
                       videoFrameNumber++;
                   }
                   // Extract a thumbnail for each I-Frame
                   if (videoFrameType == 0x65)
                   {
                       decodeIFrame(h264, spsFrame, spsFrameLength, ppsFrame, ppsFrameLength, data, dataLen);
                   }
                   if (videoStream != NULL)
                   {
                       AVPacket pkt = { 0 };
                       av_init_packet(&amp;pkt);
                       pkt.stream_index = vi;
                       pkt.flags = 0;          
                       pkt.pts = videoFrameNumber;
                       pkt.dts = videoFrameNumber;          
                       if (videoFrameType == 0x65)
                       {
                           pkt.flags = 1;                          

                           unsigned char* videoFrame = new unsigned char[spsFrameLength+ppsFrameLength+dataLen];
                           memcpy(videoFrame, spsFrame, spsFrameLength);
                           memcpy(&amp;videoFrame[spsFrameLength], ppsFrame, ppsFrameLength);

                           memcpy(&amp;videoFrame[spsFrameLength+ppsFrameLength], data, dataLen);
                           pkt.data = videoFrame;
                           av_interleaved_write_frame(oc, &amp;pkt);
                           delete videoFrame; videoFrame = NULL;
                       }
                       else if (videoFrameType != 0x67 &amp;&amp; videoFrameType != 0x68)
                       {                      
                           pkt.size = dataLen;
                           pkt.data = data;
                           av_interleaved_write_frame(oc, &amp;pkt);
                       }                      
                   }
                   break;
               }

           case TCP_PACKET_AAC:

               if (firstAudioTimeStamp == 0)
               {
                   firstAudioTimeStamp = block->getTimeStamp();
                   uint64_t millseconds_difference = firstAudioTimeStamp - firstVideoTimeStamp;
                   audioStartOffset = millseconds_difference * 16000 / 1000;
                   cout &lt;&lt; "audio offset: " &lt;&lt; audioStartOffset &lt;&lt; endl;
               }

               if (audioStream != NULL)
               {
                   AVPacket pkt = { 0 };
                   av_init_packet(&amp;pkt);
                   pkt.stream_index = ai;
                   pkt.flags = 1;          
                   pkt.pts = audioFrameNumber*1024;
                   pkt.dts = audioFrameNumber*1024;
                   pkt.data = block->getData();
                   pkt.size = block->getDataLen();
                   pkt.duration = 1024;

                   AVPacket newpacket = pkt;                      
                   int rc = av_bitstream_filter_filter(bsfc, audioContext,
                       NULL,
                       &amp;newpacket.data, &amp;newpacket.size,
                       pkt.data, pkt.size,
                       pkt.flags &amp; AV_PKT_FLAG_KEY);

                   if (rc >= 0)
                   {
                       //cout &lt;&lt; "Write audio frame" &lt;&lt; endl;
                       newpacket.pts = audioFrameNumber*1024;
                       newpacket.dts = audioFrameNumber*1024;
                       audioFrameNumber++;
                       newpacket.duration = 1024;                  

                       av_interleaved_write_frame(oc, &amp;newpacket);
                       av_free_packet(&amp;newpacket);
                   }  
                   else
                   {
                       cout &lt;&lt; "Error filtering aac packet" &lt;&lt; endl;

                   }
               }
               break;

           case TCP_PACKET_START:
               break;

           case TCP_PACKET_END:
               break;
           }
           delete block;
       }
       inFile.close();

       av_write_trailer(oc);
       int i = 0;
       for (i = 0; i &lt; oc->nb_streams; i++)
       {
           av_freep(&amp;oc->streams[i]->codec);
           av_freep(&amp;oc->streams[i]);      
       }

       if (!(oc->oformat->flags &amp; AVFMT_NOFILE))
       {
           avio_close(oc->pb);
       }

       av_free(oc);

       delete spsFrame; spsFrame = NULL;
       delete ppsFrame; ppsFrame = NULL;

       cout &lt;&lt; "Wrote " &lt;&lt; videoFrameNumber &lt;&lt; " video frames." &lt;&lt; endl;

       return 0;
    }
    </output></stream>

    The stream stream/codecs are added and the header is created in a function called addVideoAndAudioStream(). This function is called from decodeIFrame() so there are a few assumptions (which aren’t necessarily good)
    1. A video packet comes first
    2. AAC is present

    The decodeIFrame was kind of a separate prototype by where I was creating a thumbnail for each I Frame. The code to generate thumbnails was from : https://gnunet.org/svn/Extractor/src/plugins/thumbnailffmpeg_extractor.c

    The decodeIFrame function passes an AVCodecContext into addVideoAudioStream :

    void addVideoAndAudioStream(AVCodecContext* decoder = NULL)
    {
       videoStream = av_new_stream(oc, 0);
       if (!videoStream)
       {
           cout &lt;&lt; "ERROR creating video stream" &lt;&lt; endl;
           return;      
       }
       vi = videoStream->index;  
       videoContext = videoStream->codec;      
       videoContext->codec_type = AVMEDIA_TYPE_VIDEO;
       videoContext->codec_id = decoder->codec_id;
       videoContext->bit_rate = 512000;
       videoContext->width = decoder->width;
       videoContext->height = decoder->height;
       videoContext->time_base.den = 25;
       videoContext->time_base.num = 1;
       videoContext->gop_size = decoder->gop_size;
       videoContext->pix_fmt = decoder->pix_fmt;      

       audioStream = av_new_stream(oc, 1);
       if (!audioStream)
       {
           cout &lt;&lt; "ERROR creating audio stream" &lt;&lt; endl;
           return;
       }
       ai = audioStream->index;
       audioContext = audioStream->codec;
       audioContext->codec_type = AVMEDIA_TYPE_AUDIO;
       audioContext->codec_id = CODEC_ID_AAC;
       audioContext->bit_rate = 64000;
       audioContext->sample_rate = 16000;
       audioContext->channels = 1;

       if (oc->oformat->flags &amp; AVFMT_GLOBALHEADER)
       {
           videoContext->flags |= CODEC_FLAG_GLOBAL_HEADER;
           audioContext->flags |= CODEC_FLAG_GLOBAL_HEADER;
       }

       av_dump_format(oc, 0, filename, 1);

       if (!(oc->oformat->flags &amp; AVFMT_NOFILE))
       {
           if (avio_open(&amp;oc->pb, filename, AVIO_FLAG_WRITE) &lt; 0) {
               cout &lt;&lt; "Error opening file" &lt;&lt; endl;
           }
       }

       avformat_write_header(oc, NULL);
    }

    As far as I can tell, a number of assumptions didn’t seem to matter, for example :
    1. Bit Rate. The actual video bit rate was 262k whereas I specified 512kbit
    2. AAC channels. I specified mono, although the actual output was Stereo from memory

    You would still need to know what the frame rate (time base) is for the video & audio.

    Contrary to a lot of other examples, when setting pts & dts on the video packets, it was not playable. I needed to know the time base (25fps) and then set the pts & dts according to that time base, i.e. first frame = 0 (PPS, SPS, I), second frame = 1 (intermediate frame, whatever its called ;)).

    AAC I also had to make the assumption that it was 16000 hz. 1024 samples per AAC packet (You can also have AAC @ 960 samples I think) to determine the audio "offset". I added this to the pts & dts. So the pts/dts are the sample number that it is to played back at. You also need to make sure that the duration of 1024 is set in the packet before writing also.

    I have found additionally today that Annex B isn’t really compatible with any other player so AVCC format should really be used.

    These URLS helped :
    Problem to Decode H264 video over RTP with ffmpeg (libavcodec)
    http://aviadr1.blogspot.com.au/2010/05/h264-extradata-partially-explained-for.html

    When constructing the video stream, I filled out the extradata & extradata_size :

    // Extradata contains PPS &amp; SPS for AVCC format
    int extradata_len = 8 + spsFrameLen-4 + 1 + 2 + ppsFrameLen-4;
    videoContext->extradata = (uint8_t*)av_mallocz(extradata_len);
    videoContext->extradata_size = extradata_len;
    videoContext->extradata[0] = 0x01;
    videoContext->extradata[1] = spsFrame[4+1];
    videoContext->extradata[2] = spsFrame[4+2];
    videoContext->extradata[3] = spsFrame[4+3];
    videoContext->extradata[4] = 0xFC | 3;
    videoContext->extradata[5] = 0xE0 | 1;
    int tmp = spsFrameLen - 4;
    videoContext->extradata[6] = (tmp >> 8) &amp; 0x00ff;
    videoContext->extradata[7] = tmp &amp; 0x00ff;
    int i = 0;
    for (i=0;iextradata[8+i] = spsFrame[4+i];
    videoContext->extradata[8+tmp] = 0x01;
    int tmp2 = ppsFrameLen-4;  
    videoContext->extradata[8+tmp+1] = (tmp2 >> 8) &amp; 0x00ff;
    videoContext->extradata[8+tmp+2] = tmp2 &amp; 0x00ff;
    for (i=0;iextradata[8+tmp+3+i] = ppsFrame[4+i];

    When writing out the frames, don’t prepend the SPS & PPS frames, just write out the I Frame & P frames. In addition, replace the Annex B start code contained in the first 4 bytes (0x00 0x00 0x00 0x01) with the size of the I/P frame.

  • ffmpeg - operation not permitted error while conversion

    20 février 2012, par Jomoos

    I am developing an android app. My requirement is that to implement an rtsp streaming server on android. It has to live stream video and audio captured using MediaRecorder. Another requirement is that I have to use live555 as the streaming server. What I get from MediaRecorder is in MP4 or 3GP format. live555 cannot able to stream both. But it can stream audio if I recorded it only in 'RAW_AMR' format. Since live555 support 'mpg' format for streaming, I decided to put someone in middle who can convert 'mp4' or '3gp' to 'mpg', and I chose ffmpeg.

    I have ported live555 and ffmpeg to android. ffmpeg is able to convert the file recorded by MediaRecorder once it is finished. But the problem is that ffmpeg cannot be able to do it concurrently. That is, ffmpeg is not able to convert the file while recording. It shows an Operation not permitted error. I tried the same on my linux machine, using VLC to record instead of MediaRecorder on android. The result is same. ffmpeg is able to convert once the recording is finished, and not able to do the same while recording.

    Here is the ffmpeg command I issued on my linux box :

    ffmpeg -v 9 -loglevel 99 -i test.mp4 test.mpg

    Where test.mp4 is the file to which VLC is recording in mp4 format. and test.mpg is my destination file. The following is the output by ffmpeg on terminal.

    ffmpeg version 0.8.9, Copyright (c) 2000-2011 the FFmpeg developers
     built on Feb  1 2012 18:29:27 with gcc 4.6.2 20111027 (Red Hat 4.6.2-1)
     configuration: --prefix=/usr --bindir=/usr/bin --datadir=/usr/share/ffmpeg --incdir=/usr/include/ffmpeg --libdir=/usr/lib64 --mandir=/usr/share/man --arch=x86_64 --extra-cflags=&#39;-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m64 -mtune=generic&#39; --enable-bzlib --enable-libcelt --enable-libdc1394 --enable-libdirac --enable-libfreetype --enable-libgsm --enable-libmp3lame --enable-libopenjpeg --enable-librtmp --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxvid --enable-x11grab --enable-avfilter --enable-postproc --enable-pthreads --disable-static --enable-shared --enable-gpl --disable-debug --disable-stripping --shlibdir=/usr/lib64 --enable-runtime-cpudetect
     libavutil    51.  9. 1 / 51.  9. 1
     libavcodec   53.  8. 0 / 53.  8. 0
     libavformat  53.  5. 0 / 53.  5. 0
     libavdevice  53.  1. 1 / 53.  1. 1
     libavfilter   2. 23. 0 /  2. 23. 0
     libswscale    2.  0. 0 /  2.  0. 0
     libpostproc  51.  2. 0 / 51.  2. 0
    [mov,mp4,m4a,3gp,3g2,mj2 @ 0x1672600] Format mov,mp4,m4a,3gp,3g2,mj2 probed with size=2048 and score=100
    [mov,mp4,m4a,3gp,3g2,mj2 @ 0x1672600] ISO: File Type Major Brand: isom
    [mov,mp4,m4a,3gp,3g2,mj2 @ 0x1672600] moov atom not found
    test.mp4: Operation not permitted

    Would anyone please tell me what is causing the problem ? Or is the scenario above is possible by ffmpeg. That is, is ffmpeg is able to do the conversion at the same time as that of recording ? If it is not possible by ffmpeg, would you please suggest any alternative solutions ?

    NOTE : I am putting a C tag because if it possible by some tweaking in C on ffmpeg, I am ready to do that(I want the solution that badly). But please provide some pointers to the right direction.