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  • List of compatible distributions

    26 avril 2011, par

    The table below is the list of Linux distributions compatible with the automated installation script of MediaSPIP. Distribution nameVersion nameVersion number Debian Squeeze 6.x.x Debian Weezy 7.x.x Debian Jessie 8.x.x Ubuntu The Precise Pangolin 12.04 LTS Ubuntu The Trusty Tahr 14.04
    If you want to help us improve this list, you can provide us access to a machine whose distribution is not mentioned above or send the necessary fixes to add (...)

  • MediaSPIP v0.2

    21 juin 2013, par

    MediaSPIP 0.2 est la première version de MediaSPIP stable.
    Sa date de sortie officielle est le 21 juin 2013 et est annoncée ici.
    Le fichier zip ici présent contient uniquement les sources de MediaSPIP en version standalone.
    Comme pour la version précédente, il est nécessaire d’installer manuellement l’ensemble des dépendances logicielles sur le serveur.
    Si vous souhaitez utiliser cette archive pour une installation en mode ferme, il vous faudra également procéder à d’autres modifications (...)

  • MediaSPIP version 0.1 Beta

    16 avril 2011, par

    MediaSPIP 0.1 beta est la première version de MediaSPIP décrétée comme "utilisable".
    Le fichier zip ici présent contient uniquement les sources de MediaSPIP en version standalone.
    Pour avoir une installation fonctionnelle, il est nécessaire d’installer manuellement l’ensemble des dépendances logicielles sur le serveur.
    Si vous souhaitez utiliser cette archive pour une installation en mode ferme, il vous faudra également procéder à d’autres modifications (...)

Sur d’autres sites (9407)

  • FFmpeg outputs corrupted NAL units

    9 mai 2020, par UrsulAerodinamic

    I need to stream the screen of my Windows PC to Android. I intend to use FFmpeg to capture the screen and encode using H.264 codec, send the stream through RTP and finally use MediaCodec to decode the video and display it on a SurfaceView.

    



    I tried the following FFmpeg command :

    



    ffmpeg -f gdigrab -i desktop -an -video_size 1920x1080 -f rtp rtp://192.168.0.12:23000


    



    However, all the NAL units that result seem to be corrupted, because :

    



      


    1. The forbidden_zero_bit (most significant bit) of the NAL unit header is 1. For example, header of the NAL unit shown below (the byte right after 0x00 0x00 0x01) is 0xB6, so clearly the most significant bit is equal to 1.

      2. 


    2. A lot of bytes in the NAL unit are equal to 0xFF. I don't actually know if they are supposed to be like this, they just seem weird to me.

      3. 


    



    This is the beginning of one of the NAL units outputted by FFmpeg, captured with Wireshark :

    



    0000   00 00 01 b6 56 5a bc 7c fd de ea e7 72 ff ff ff
0010   ff ff ff ef 7d d7 ff bd 6f 5f ff ee d7 ba bf ff
0020   fd df bd 7b a5 ff ff ff ff ff fd d7 78 bf fd e2
0030   ff ff ff ff ff ff 7b fe eb ff ff ff ff ff ff ff
0040   fe f5 ff ff ff ff fd b4 c6 17 45 ba 7e f4 e9 fb
0050   d7 ef 7f de ff ff ff ff fd d7 ff 79 ff bc ff ff
0060   ff ff ff ff ff ba ff ff ff ff ff ff ff 7b ff f7
0070   27 ff ff ff de ff ff ff ff ff ff ff fe ef fd c7
0080   de ef 6f 7b db dd db 74 de dd 37 bd ef ff ff ff
0090   ff ff ff ff 77 bb ff 75 ee ee bf ff ff fb dd df
00a0   ee d7 79 5e 5f ff ff ff fb 9b ff fb d7 ff ff ff
00b0   de bf ff ff ff ff ff ff ff ff fb 9d ef bd df 00
00c0   00 8f 03 ef ff ff ff ff ff ff ff 7b f7 03 1f fd
00d0   ed e5 ba ef 5d d5 cc 5f ff ff ff ff ff ff ff ff
00e0   ff ff ff ee 06 37 be f4 f6 eb ff ff ff ff ff ff
00f0   ff ff ff ff ff ff ff ba 5f f7 af ff ff ff ff ff
0100   ff ff ff ff ff ff ff ff fd d3 fb c2 ef 1b dd ed
...
...
...


    



    Screenshot from Wireshark (same NAL unit)

    



    I also tried specifying the video codec explicitly in FFmpeg, like this :

    



    ffmpeg -f gdigrab -i desktop -an -vcodec libx264 -f rtp rtp://192.168.0.12:23000


    



    In this case, I don't get Annex B style NAL units, but AVCC style ones (without the 0x00 0x00 0x01 separators, but preceded by their length, as described here).

    



    With AVCC NAL units I don't really understand where one ends and another begins, and also where that "extradata" mentioned in the question linked above is.

    



    In summary, what I want to know is as follows :

    



      


    1. Why are the NAL units outputted by the first command corrupted ?

      2. 


    2. From what I understand (from here), you have to feed separate NAL units to MediaCodec for decoding. So, how do I separate NAL units in AVCC format from one another ?

      3. 


    3. Can I somehow force FFmpeg to output Annex B style NAL units instead of AVCC ones while specifying the video codec as libx264 ?

      4. 


    4. Is there a more straightforward way of capturing the screen on Windows, encoding, sending the stream to the Android device and displaying the video in my app ? (maybe a library or an API that is escaping my notice)

      5. 


    


  • Decoding video packets received from TCPReplay using C++/Qt

    12 septembre 2020, par Lakshya

    I have a PCAP file having the encoded video data. I am using TCPReplay to broadcast this PCAP data to my server.

    


    In my server I have written a QT UDP socket program to receive these packets. I am able to receive these packets successfully in my server and stored the data in QByteArray.

    


    Here I am using PCAP file and TCPReplay as a simulator. In reality these packets will be received from another process/server.

    


    I would like to decode these packets. How can I decode these packets in C++/Qt ?

    


    What data structure to use ? Do I need to use FFMPEG or gstreamer APIs ?

    


    I am completely new to video decoding.

    


    So please elaborate answer with some sample code.

    


    Here is my hex values copied from Wireshark ;-

    


    0000 00 0c 29 02 e2 f7 04 91 62 ca 68 51 08 00 45 00 ..).....b.hQ..E.
0010 05 ba 00 00 00 00 80 11 5f f4 0a 00 02 0f c0 a8 ........_.......
0020 08 88 c3 51 c3 51 05 a6 00 00 54 50 54 82 00 00 ...Q.Q....TPT...
0030 40 01 01 01 05 88 91 5a fb 3b 37 90 cd c7 11 35 @......Z. ;7....5
0040 56 03 20 20 02 0b e2 00 0a 80 08 00 09 80 08 00 V. ............
0050 08 64 64 64 06 00 00 00 00 00 00 00 00 00 00 00 .ddd............
0060 64 64 64 64 64 64 ff ff 64 64 64 64 64 64 ff ff dddddd..dddddd..
0070 64 64 64 64 64 64 f8 02 00 00 00 00 00 00 04 00 dddddd..........
0080 64 64 64 64 64 64 ff ff 64 64 64 64 64 64 ff ff dddddd..dddddd..
0090 64 64 64 64 64 64 ff ff 64 64 64 64 64 64 ff ff dddddd..dddddd..
00a0 64 64 64 64 64 64 ff ff 64 64 64 64 64 64 ff ff dddddd..dddddd..
00b0 64 64 64 64 64 64 ac e1 00 00 00 00 00 66 00 01 dddddd.......f..
00c0 5c 80 ff 80 80 ff 00 01 80 80 ff 80 80 ff 00 02 ...............
00d0 5c 33 00 00 00 00 00 01 64 64 64 64 64 64 03 eb \3......dddddd..
00e0 00 ff 00 00 ff 00 00 04 00 ff 00 00 00 00 00 01 ................
00f0 64 64 64 64 64 64 00 0b 00 00 00 00 00 66 00 01 dddddd.......f..
0100 5c 80 ff 80 80 b6 00 01 33 00 00 00 00 00 00 01 .......3.......
0110 64 64 64 64 64 64 00 0d 00 00 66 5c 80 ff 00 01 dddddd....f....
0120 80 80 b6 33 00 66 00 01 5c 80 ff 80 80 b6 00 01 ...3.f.........
0130 33 00 00 00 00 00 00 01 64 64 64 64 64 64 03 dc 3.......dddddd..
0140 00 ff 00 00 00 00 00 01 64 64 64 64 64 64 00 03 ........dddddd..
0150 00 ff 00 00 00 00 00 01 64 64 64 64 64 64 00 0b ........dddddd..
0160 00 00 00 00 00 66 00 01 5c 80 ff 80 80 b6 00 01 .....f.........
0170 33 00 00 00 00 00 00 01 64 64 64 64 64 64 00 0e 3.......dddddd..
0180 00 00 00 00 00 66 00 01 5c 80 ff 80 80 b6 00 01 .....f.........
0190 33 00 00 00 00 00 00 01 64 64 64 64 64 64 03 dc 3.......dddddd..
01a0 00 ff 00 00 00 00 00 01 64 64 64 64 64 64 00 03 ........dddddd..
01b0 00 ff 00 00 00 00 00 01 64 64 64 64 64 64 00 0b ........dddddd..
01c0 00 00 00 00 00 66 00 01 5c 80 ff 80 80 b6 00 01 .....f.........
01d0 33 00 00 00 00 00 00 01 64 64 64 64 64 64 00 01 3.......dddddd..
01e0 1d 48 db 80 80 ff 00 01 80 80 ff 80 80 ff 00 01 .H..............
01f0 80 80 ff 80 80 b6 00 01 33 00 3a 48 6e ff 00 01 ........3.:Hn...
0200 80 80 ff 6e 48 3a 00 01 00 00 3a 48 6e ff 00 01 ...nH :....:Hn...
0210 80 80 ff 6e 48 3a 00 01 00 00 66 5c 80 ff 00 01 ...nH :....f....
0220 80 80 ff 80 80 ff 00 01 80 80 ff 5c 33 00 00 01 ...........\3...
0230 00 00 66 5c 80 ff 00 01 80 80 ff 80 80 ff 00 02 ..f............
0240 80 80 b6 5c 5c ff 00 01 80 80 ff 80 80 ff 00 01 ...\...........
0250 80 80 b6 33 00 00 00 01 00 00 66 5c 80 ff 00 01 ...3......f....
0260 80 80 ff 80 80 ff 00 01 80 80 ff 80 5c 66 00 01 ............\f..
0270 00 00 00 00 33 b6 00 01 80 80 ff 80 80 ff 00 01 ....3...........
0280 80 80 ff 80 6e 90 00 01 1d 00 00 00 00 00 00 01 ....n...........
0290 64 64 64 64 64 64 03 d5 00 ff 00 00 00 00 00 01 dddddd..........
02a0 64 64 64 64 64 64 00 03 00 ff 00 00 00 00 00 01 dddddd..........
02b0 64 64 64 64 64 64 00 0b 00 00 00 00 00 66 00 01 dddddd.......f..
02c0 5c 80 ff 80 80 ff 00 01 80 80 ff 80 80 ff 00 01 ...............
02d0 80 80 ff 80 5c 66 00 01 64 64 64 64 64 64 00 02 ....\f..dddddd..
02e0 1d 48 db 80 80 ff 00 01 6e 48 3a 00 1d 90 00 01 .H......nH :.....
02f0 6e 80 ff 80 6e 90 00 01 1d 1d 90 6e 80 ff 00 01 n...n......n....
0300 80 80 b6 33 00 3a 00 01 48 6e ff 80 80 ff 00 01 ...3. :..Hn......
0310 6e 48 3a 00 00 66 00 01 5c 80 ff 80 80 db 00 01 nH :..f.........
0320 48 1d 66 5c 80 ff 00 01 80 80 ff 5c 33 00 00 01 H.f.......\3...
0330 00 00 66 5c 80 ff 00 01 80 80 b6 33 00 66 00 01 ..f.......3.f..
0340 5c 80 ff 80 80 b6 00 01 33 00 00 00 00 3a 00 01 .......3.... :..
0350 48 6e ff 80 80 db 00 01 48 1d 00 00 00 00 00 01 Hn......H.......
0360 33 5c ff 80 80 ff 00 01 6e 48 66 48 6e ff 00 01 3......nHfHn...
0370 80 80 db 48 1d 00 00 01 33 5c ff 80 80 ff 00 01 ...H....3......
0380 6e 48 3a 00 00 00 00 01 64 64 64 64 64 64 00 0b nH :.....dddddd..
0390 00 00 00 02 05 17 00 01 64 64 64 64 64 64 03 c9 ........dddddd..
03a0 00 ff 00 00 00 00 00 01 ff ff 00 ff ff 00 00 02 ................
03b0 ff ff 00 00 00 00 00 01 00 ff 00 00 00 00 00 01 ................
03c0 64 64 64 64 64 64 00 0b 00 00 00 00 00 66 00 01 dddddd.......f..
03d0 5c 80 ff 80 80 b6 00 01 33 00 00 00 00 00 00 01 .......3.......
03e0 64 64 64 64 64 64 00 01 00 00 3a 48 6e ff 00 01 dddddd....:Hn...
03f0 80 80 ff 80 80 ff 00 02 6e 48 3a 00 00 3a 00 01 ........nH :.. :..
0400 48 6e ff 80 80 ff 00 01 80 80 ff 80 80 ff 00 01 Hn..............
0410 80 5c 66 00 00 66 00 01 5c 80 ff 80 80 b6 00 01 .\f..f.........
0420 33 00 00 00 00 00 00 01 1d 48 db 80 80 ff 00 01 3........H......
0430 6e 48 90 5c 80 ff 00 01 80 80 b6 33 00 00 00 01 nH........3....
0440 00 00 66 5c 80 ff 00 01 80 80 b6 33 00 66 00 01 ..f.......3.f..
0450 5c 80 ff 80 80 b6 00 01 33 00 00 00 00 66 00 01 .......3....f..
0460 5c 80 ff 80 80 ff 00 01 80 80 ff 80 80 ff 00 02 ...............
0470 80 5c 66 33 5c ff 00 01 80 80 ff 80 80 ff 00 01 .\f3...........
0480 80 6e 90 1d 00 00 00 01 64 64 64 64 64 64 00 0c .n......dddddd..
0490 00 00 00 02 05 17 00 01 02 04 13 00 01 05 00 01 ................
04a0 64 64 64 64 64 64 03 c8 00 ff 00 00 00 00 00 01 dddddd..........
04b0 64 64 64 64 64 64 00 03 00 ff 00 00 00 00 00 01 dddddd..........
04c0 64 64 64 64 64 64 00 0b 00 00 00 00 00 66 00 01 dddddd.......f..
04d0 5c 80 ff 80 80 b6 00 01 33 00 00 00 00 00 00 01 .......3.......
04e0 00 00 00 00 00 3a 00 01 48 6e ff 80 80 ff 00 01 ..... :..Hn......
04f0 5c 33 00 00 00 00 00 01 1d 48 db 80 80 ff 00 01 \3.......H......
0500 6e 48 3a 00 00 00 00 01 1d 48 db 80 80 ff 00 01 nH :......H......
0510 80 80 ff 80 80 db 00 01 48 1d 00 00 00 66 00 01 ........H....f..
0520 5c 80 ff 80 80 b6 00 01 33 00 00 00 00 00 00 01 .......3.......
0530 1d 48 db 80 80 ff 00 01 6e 48 90 5c 80 ff 00 01 .H......nH.....
0540 80 80 b6 33 00 00 00 01 00 00 66 5c 80 ff 00 01 ...3......f....
0550 80 80 b6 33 00 66 00 01 5c 80 ff 80 80 b6 00 01 ...3.f.........
0560 33 00 00 00 1d 90 00 01 6e 80 ff 80 80 b6 00 01 3.......n.......
0570 33 00 00 00 00 00 00 01 64 64 64 64 64 64 00 02 3.......dddddd..
0580 00 00 00 00 33 b6 00 01 80 80 ff 80 80 ff 00 01 ....3...........
0590 80 5c 66 00 00 00 00 01 64 64 64 64 64 64 00 0b .\f.....dddddd..
05a0 00 00 00 02 05 17 00 01 e5 e6 e8 02 04 13 00 01 ................
05b0 64 64 64 64 64 64 03 c8 00 ff 00 00 00 00 00 01 dddddd..........
05c0 64 64 64 64 64 64 00 03 dddddd..

    


    


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  • Revision 3549 : On replace correctement par rapport à la hauteur dans le cas ou la video ...

    8 juin 2010, par kent1 — Log

    On replace correctement par rapport à la hauteur dans le cas ou la video fullscreen ne peut être affiché dans toute la hauteur

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