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  • Des sites réalisés avec MediaSPIP

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    Cette page présente quelques-uns des sites fonctionnant sous MediaSPIP.
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    13 avril 2011, par

    Talk to people directly involved in MediaSPIP’s development, or to people around you who could use MediaSPIP to share, enhance or develop their creative projects.
    The bigger the community, the more MediaSPIP’s potential will be explored and the faster the software will evolve.
    A discussion list is available for all exchanges between users.

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    13 avril 2011

    MediaSPIP is based on a system of themes and templates. Templates define the placement of information on the page, and can be adapted to a wide range of uses. Themes define the overall graphic appearance of the site.
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    I know when converting to x264 if I choose CBR, it will deteriorate the video quality but I am OK with it since I want to use it for streaming.

    Please help me asap

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  • How can I capture audio AND video simultenaous with ffmpeg from an USB capture device

    5 octobre 2011, par oban

    I'm capturing a video by means of an USB Terratec Grabster AV350 (which is based on the em2860 chip).

    I don't succeed to get the audio when it is played . If I play the captured video with vlc or with ffplay I got only 3 seconds sound and then a silence for the rest of the video ...

    During the capturing I don't get any errors. At the end it indicates the size of the video and audio captured ....

    I'm using the ffmpeg command for this :

    ffmpeg -f alsa -ac 2 -i hw:3 -f video4linux2 -i /dev/video0 -acodec ac3 -ab 128k -vcodec mpeg4 -b 6000k -r 25 test5.avi

    The log is :

    [alsa @ 0x9bcd420]Estimating duration from bitrate, this may be inaccurate
    Input #0, alsa, from 'hw:3' :
    Duration : N/A, start : 69930.998994, bitrate : N/A
    Stream #0.0 : Audio : pcm_s16le, 44100 Hz, 2 channels, s16, 1411 kb/s
    [video4linux2 @ 0x9bf5d30]Estimating duration from bitrate, this may be inaccurate
    Input #1, video4linux2, from '/dev/video0' :
    Duration : N/A, start : 1307111377.654173, bitrate : -2147483 kb/s
    Stream #1.0 : Video : rawvideo, yuyv422, 720x576, -2147483 kb/s, 1000k tbr, 1000k tbn, 1000k tbc
    [ac3 @ 0x9bf9590]No channel layout specified. The encoder will guess the layout, but it might be incorrect.
    Output #0, avi, to 'test5.avi' :
    Metadata :
    ISFT : Lavf52.64.2
    Stream #0.0 : Video : mpeg4, yuv420p, 720x576, q=2-31, 6000 kb/s, 25 tbn, 25 tbc
    Stream #0.1 : Audio : ac3, 44100 Hz, stereo, s16, 128 kb/s
    Stream mapping :
    Stream #1.0 -> #0.0
    Stream #0.0 -> #0.1
    Press [q] to stop encoding
    frame= 1283 fps= 25 q=2.3 Lsize= 38677kB time=51.32 bitrate=6173.9kbits/s
    video:37755kB audio:846kB global headers:0kB muxing overhead 0.198922%

    If I reduce the command for only capturing audio, then the audio file can be played successfully :

    ffmpeg -f alsa -ac 2 -i hw:3,0 -acodec ac3 -ab 128k test5.avi

    [alsa @ 0x8ede420]Estimating duration from bitrate, this may be inaccurate
    Input #0, alsa, from 'hw:3,0' :
    Duration : N/A, start : 70395.998935, bitrate : N/A
    Stream #0.0 : Audio : pcm_s16le, 44100 Hz, 2 channels, s16, 1411 kb/s
    [ac3 @ 0x8eebac0]No channel layout specified. The encoder will guess the layout, but it might be incorrect.
    Output #0, avi, to 'test5.avi' :
    Metadata :
    ISFT : Lavf52.64.2
    Stream #0.0 : Audio : ac3, 44100 Hz, stereo, s16, 128 kb/s
    Stream mapping :
    Stream #0.0 -> #0.0
    Press [q] to stop encoding
    size= 227kB time=13.62 bitrate= 136.8kbits/s
    video:0kB audio:213kB global headers:0kB muxing overhead 6.902375%

    If I run the command for only video capturing then vlc or ffplay can play the video successfully :

    ffmpeg -f video4linux2 -i /dev/video0 -vcodec mpeg4 -b 12000k -r 25 test5.avi

    [video4linux2 @ 0x91d6420]Estimating duration from bitrate, this may be inaccurate
    Input #0, video4linux2, from '/dev/video0' :
    Duration : N/A, start : 1307112044.025687, bitrate : -2147483 kb/s
    Stream #0.0 : Video : rawvideo, yuyv422, 720x576, -2147483 kb/s, 1000k tbr, 1000k tbn, 1000k tbc
    Output #0, avi, to 'test5.avi' :
    Metadata :
    ISFT : Lavf52.64.2
    Stream #0.0 : Video : mpeg4, yuv420p, 720x576, q=2-31, 12000 kb/s, 25 tbn, 25 tbc
    Stream mapping :
    Stream #0.0 -> #0.0
    Press [q] to stop encoding
    frame= 388 fps= 25 q=2.0 Lsize= 12963kB time=15.52 bitrate=6842.5kbits/s
    video:12949kB audio:0kB global headers:0kB muxing overhead 0.114584%

    Strange behaviour I noticed is that when I tried capturing video and audio, I can not capture the audio afterwards any more,
    unless I unplug the AV350 first.

    The G350 is located at card 3 :

    htpc@htpc-01 :/proc/asound/G350/pcm0c$ more info
    card : 3
    device : 0
    subdevice : 0
    stream : CAPTURE
    id : USB Audio
    name : USB Audio
    subname : subdevice #0
    class : 0
    subclass : 0
    subdevices_count : 1
    subdevices_avail : 1

    The OS is a Linux 2.6.38-8-generic with the Ubuntu Natty Narwhal version

    Any help on how to tackle this issue would be great ....

    Thanks !

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