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Autres articles (95)
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MediaSPIP 0.1 Beta version
25 avril 2011, parMediaSPIP 0.1 beta is the first version of MediaSPIP proclaimed as "usable".
The zip file provided here only contains the sources of MediaSPIP in its standalone version.
To get a working installation, you must manually install all-software dependencies on the server.
If you want to use this archive for an installation in "farm mode", you will also need to proceed to other manual (...) -
Multilang : améliorer l’interface pour les blocs multilingues
18 février 2011, parMultilang est un plugin supplémentaire qui n’est pas activé par défaut lors de l’initialisation de MediaSPIP.
Après son activation, une préconfiguration est mise en place automatiquement par MediaSPIP init permettant à la nouvelle fonctionnalité d’être automatiquement opérationnelle. Il n’est donc pas obligatoire de passer par une étape de configuration pour cela. -
HTML5 audio and video support
13 avril 2011, parMediaSPIP uses HTML5 video and audio tags to play multimedia files, taking advantage of the latest W3C innovations supported by modern browsers.
The MediaSPIP player used has been created specifically for MediaSPIP and can be easily adapted to fit in with a specific theme.
For older browsers the Flowplayer flash fallback is used.
MediaSPIP allows for media playback on major mobile platforms with the above (...)
Sur d’autres sites (7974)
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Inconsistent behaviour of ffmpeg -i flag
19 mai 2021, par zeebrahI'm trying to write a Bash script that would download an audio track from youtube and convert it to Apple ringtone format, which is .m4r. The tools I employ are
youtube-dlandffmpeg. The former seems to work fine but I have a strange issue with the latter. When I try to pass the name of the file parametrically, shell prints that file or directory can't be found.


I use the same method for unwraping user input (or my defaults) for both commands but it only seems to work with
youtube-dl.

Example of what doesn't work and print the text above. Obviously, all the files are in fact there and accessible


youtube-dl -i --extract-audio --audio-format m4a -o $filepath_interim --audio-quality 0 $video_link
ffmpeg -i $filepath_interim -acodec copy -f ipod -ss $offset -t $length $filepath_out


So, I tried to do it with
''strings,$(command)syntax, it all failed. I only found one way to make it work, which is to hard code the values of the paths but this defeats the whole purpose of my script.

youtube-dl -i --extract-audio --audio-format m4a -o $filepath_interim --audio-quality 0 $video_link
ffmpeg -i ~/Downloads/ringtone.m4a -acodec copy -f ipod -ss $offset -t $length ~/Downloads/ringtone.m4r


I want to figure out why this keeps happening, whether it is in any way specific to
ffmpegor am I just missing some piece of knowledge about$name unwrapping.

Minimal Working Example. Run with bash or pack in script and run. If your path to
bashis different, please change the shebang :

#!/usr/local/bin/bash
# initialise
filepath_interim="~/Downloads/ringtone.m4a"
filepath_out="~/Downloads/ringtone.m4r"
video_link="https://www.youtube.com/watch?v=dQw4w9WgXcQ"
offset=0
length=30

# main part
youtube-dl -i --extract-audio --audio-format m4a -o $filepath_interim --audio-quality 0 $video_link
ffmpeg -i $filepath_interim -acodec copy -f ipod -ss $offset -t $length $filepath_out


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SDL2 won't play with more than 6 audio channels
13 juin 2020, par Hiko HaietoI am trying to stream (raw) video and audio from a capture device as part of my home media setup (with my pc acting similarly to a receiver in a typical home theatre setup), but the biggest problem I haven't been able to get past is that I haven't been able to get ffplay (using SDL2 as its audio backend) to work with all 8 channels in 7.1 streams - two simply get dropped, despite it recognising 8 channel input or me specifying a 7.1 layout.



I have been able to confirm that all 8 channels are present in the source by first using ffmpeg to save the output of a speaker test to a file and playing that back with both mplayer (which works) and ffplay (which doesn't). I also wrote some minimal code to play the audio directly through SDL's API with the same result, so it's not the fault of ffplay. I might simply use mplayer if it weren't for the fact that piping output from ffmpeg adds too much latency for real-time use. I am using libSDL version 2.0.12 and ffplay 4.2.3, both of which are the latest at the time of writing and are ostensibly supposed to support 7.1 audio.



Using output recorded from
speaker-test -c 8, I am using the following to play it back in mplayer :


mplayer -channels 8 -rawaudio channels=8 -format s16le -demuxer rawaudio speaker-test.pcm



and the following to play it back in ffplay :



ffplay -f s16le -ac 8 -af 'channelmap=channel_layout=7.1' speaker-test.pcm



No matter what I try, the two side channels get dropped. I couldn't figure out how to play raw pcm in SDL, so I repeated the same tests with wav output and used the following code to play it back :



#include <sdl2></sdl2>SDL.h>

int main(int argc, char **argv) {
 SDL_Init(SDL_INIT_AUDIO);
 SDL_AudioSpec wavSpec;
 Uint32 wavLength;
 Uint8 *wavBuffer;
 SDL_LoadWAV("speaker-test.wav", &wavSpec, &wavBuffer, &wavLength);
 SDL_AudioDeviceID deviceID = SDL_OpenAudioDevice(NULL, 0, &wavSpec, NULL, 0);
 SDL_QueueAudio(deviceID, wavBuffer, wavLength);
 SDL_PauseAudioDevice(deviceID, 0);
 SDL_Delay(30000);
 SDL_CloseAudioDevice(deviceID);
 SDL_FreeWAV(wavBuffer);
 SDL_Quit();
 return 0;
}



The above code exhibits the same behaviour of dropping the two additional side channels, despite it being the latest version of SDL that should have supported 7.1 for many releases now. Why might this be happening, and how might I fix it ?


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ClassX installation "codec not found" due to dependencies [migrated]
25 mars 2014, par khateebClassX is an interactive lecture streaming system developed in the Electrical Engineering Department at Stanford University.
Unlike conventional lecture capturing systems, ClassX requires very simple consumer-grade equipment and minimal human operation.I faced problems during installing it, I hope you have a solution.
BTW : I successfully installed it 2 years ago, but now I think the problem as the dependencies and Ubuntu versions are different than the versions we used two years ago.
Detailed description of the problem :
- I'm using Ubuntu 12.04
- I followed the instructions @ ClassX installation guide, and all steps till step 4 are successfully done (the encoder bin file generated).
- When trying to encode the video using the classX web system, it shows the encoding completed after few seconds.However, there are no tiles generated.
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I tried to execute the command at CX_log.txt, and the following error appears.
mahmoud@Mahmoud-HP-Pavilion-dv5-Notebook-PC : $ sudo perl /var/www/ClassXWebSystem/system/publishers/web/actions/encode.pl "/var/www/ClassXWebSystem/content/encoding/FALL_2013_2014/CS106A_FALL_2013_2014/lecSEven" "/var/www/ClassXWebSystem/content/encoding/FALL_2013_2014/CS106A_FALL_2013_2014/.encoding_1372706251" "/var/www/ClassXWebSystem/content/streaming/FALL_2013_2014/CS106A_FALL_2013_2014/lecSEven" "/var/www/ClassXWebSystem/system/publishers/bin" classx y n n
[sudo] password for mahmoud :
00068.jpg
..
.
00068.mp4
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/var/www/ClassXWebSystem/content/encoding/FALL_2013_2014/CS106A_FALL_2013_2014/.encoding_1372706251/00068.mp4' :
Metadata :
major_brand : isom
minor_version : 512
compatible_brands : isomiso2avc1mp41
encoder : Lavf52.39.0
Duration : 00:02:30.05, start : 0.000000, bitrate : 8141 kb/s
Stream #0.0(und) : Video : h264, yuv420p, 1920x1080 [PAR 1:1 DAR 16:9], 8007 kb/s, 29.95 fps, 29.97 tbr, 2997 tbn, 59.94 tbc
Stream #0.1(und) : Audio : aac, 44100 Hz, stereo, s16, 128 kb/s
Output #0, mp4, to '/var/www/ClassXWebSystem/content/encoding/FALL_2013_2014/CS106A_FALL_2013_2014/.encoding_1372706251/stream0.mp4' :
Stream #0.0 : Video : [0][0][0][0] / 0x0000, yuv420p, 640x360, q=32-36, 64 kb/s, 90k tbn, 14.99 tbc
codec not found
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