
Recherche avancée
Médias (1)
-
Géodiversité
9 septembre 2011, par ,
Mis à jour : Août 2018
Langue : français
Type : Texte
Autres articles (79)
-
Le profil des utilisateurs
12 avril 2011, parChaque utilisateur dispose d’une page de profil lui permettant de modifier ses informations personnelle. Dans le menu de haut de page par défaut, un élément de menu est automatiquement créé à l’initialisation de MediaSPIP, visible uniquement si le visiteur est identifié sur le site.
L’utilisateur a accès à la modification de profil depuis sa page auteur, un lien dans la navigation "Modifier votre profil" est (...) -
Le plugin : Podcasts.
14 juillet 2010, parLe problème du podcasting est à nouveau un problème révélateur de la normalisation des transports de données sur Internet.
Deux formats intéressants existent : Celui développé par Apple, très axé sur l’utilisation d’iTunes dont la SPEC est ici ; Le format "Media RSS Module" qui est plus "libre" notamment soutenu par Yahoo et le logiciel Miro ;
Types de fichiers supportés dans les flux
Le format d’Apple n’autorise que les formats suivants dans ses flux : .mp3 audio/mpeg .m4a audio/x-m4a .mp4 (...) -
Formulaire personnalisable
21 juin 2013, parCette page présente les champs disponibles dans le formulaire de publication d’un média et il indique les différents champs qu’on peut ajouter. Formulaire de création d’un Media
Dans le cas d’un document de type média, les champs proposés par défaut sont : Texte Activer/Désactiver le forum ( on peut désactiver l’invite au commentaire pour chaque article ) Licence Ajout/suppression d’auteurs Tags
On peut modifier ce formulaire dans la partie :
Administration > Configuration des masques de formulaire. (...)
Sur d’autres sites (9995)
-
ffmpeg stops capturing whole hour of HTTP stream after some time
7 juillet 2020, par CompuChipFirst of all, sorry if I'm using the wrong terminology. I've been playing around with nginx and I'm still a bit confused about RTMP and HLS and other acronyms.


I've managed to setup OBS to stream to an nginx server, which takes the RTMP stream and chops it into pieces for HLS. Here's the relevant part of the nginx configuration file.


rtmp {
 server {
 listen 1935;
 chunk_size 4000;
 ping 30s;
 deny play all;

 application live {
 live on;
 hls on;
 hls_nested on; # Create a new folder for each stream
 hls_path /mnt/hls/live;
 hls_fragment 3s;
 hls_fragment_naming timestamp;
 hls_playlist_length 60s;
 }
 }
}

http {
 server {
 listen 81 ssl;

 #creates the http-location for our full-resolution (desktop) HLS stream - "http://localhost:8080/live/test/index.m3u8"
 location /live {
 # Elided caching and CORS for brevity

 alias /mnt/hls/live;
 add_header Cache-Control no-cache;
 index index.m3u8;
 }
 }
}



This works well, I can view the stream in VLC or on a website and it looks smooth. Now I wanted to add some logging : I'd like to write full hours (starting at xx:00:00 and ending at xx:59:59) to a file named
log_yyyymmdd_hh.mp4
, e.g.log_20200707_18.mp4
for the files of 7 July 2020, 18:00 - 19:00 hrs. So I've set up an hourly cron job with the following ffmpeg command :

ffmpeg -i https://stream.example.com:81/live/<streamkey> -preset veryfast -maxrate 2000k \
 -bufsize 2000k -g 60 -t 3600 -y /var/video/log/$(date +\%Y\%m\%d_\%H00).mp4 >/dev/null 2>&1
</streamkey>


At first this seemed to work well, so I left it running happily for about 24 hours. When I checked, most of my hourly files were small ( 100MB) files of about 10 to 15 minutes long. It seems like any small delay in the stream will cause
ffmpeg
to stop writing to the file. I suspect such hiccups may for example be caused by an OBS plugin and I'll need to look into that, but I would prefer thatffmpeg
will retry for some time before giving up. What arguments should I be passing toffmpeg
to make it not break when the stream is down for, say, up to a second every now and then ?.

When I view back the HLS files there don't seem to be any noticeable gaps, so eventually all the data arrives. I went for the
crontab
solution withffmpeg
because when recording from nginx I could not figure out how to start recording at the start of the whole hour.

-
av_hwdevice_iterate_types returns an empty list
9 juillet 2020, par Ruslan AblyazovI used an example https://github.com/FFmpeg/FFmpeg/blob/master/doc/examples/hw_decode.c


The av_hwdevice_iterate_types function returns an empty list. What could be the reason ?


And
avcodec_find_decoder_by_name("h264_cuvid")
returns NULL.

FFmpeg version :


ffmpeg version 4.3 Copyright (c) 2000-2020 the FFmpeg developers
built with gcc 8 (Debian 8.3.0-6)
configuration: --enable-gpl --enable-ladspa --enable-libpulse --enable-libsoxr --enable-libspeex --enable-avfilter --enable-avresample --enable-postproc --enable-pthreads --enable-libass --enable-libfreetype --enable-libmp3lame --enable-libx264 --enable-libx265 --enable-nonfree --disable-ffplay --enable-libxvid --enable-cuda --enable-cuda-nvcc --enable-cuvid --enable-nvenc --enable-nonfree --enable-libnpp --extra-cflags=-I/usr/local/cuda/include --extra-ldflags=-L/usr/local/cuda/lib64
libavutil 56. 51.100 / 56. 51.100
libavcodec 58. 91.100 / 58. 91.100
libavformat 58. 45.100 / 58. 45.100
libavdevice 58. 10.100 / 58. 10.100
libavfilter 7. 85.100 / 7. 85.100
libavresample 4. 0. 0 / 4. 0. 0
libswscale 5. 7.100 / 5. 7.100
libswresample 3. 7.100 / 3. 7.100
libpostproc 55. 7.100 / 55. 7.100



The command
ffmpeg -c:v h264_cuvid -i 7.mp4 71.mp4
outputs :

...
Stream mapping:
Stream #0:0 -> #0:0 (h264 (h264_cuvid) -> h264 (libx264))
....



And it works.


The command
ffmpeg-hwaccel cuda-i 7.mp4 71.mp4
outputs :

...
Stream mapping:
Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
....



The command
ffmpeg -codecs
outputs :

...
 DEV.LS h264 H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 (decoders: h264 h264_v4l2m2m h264_cuvid ) (encoders: libx264 libx264rgb h264_nvenc h264_v4l2m2m nvenc nvenc_h264 )
 D.VIL. hap Vidvox Hap
 DEV.L. hevc H.265 / HEVC (High Efficiency Video Coding) (decoders: hevc hevc_v4l2m2m hevc_cuvid ) (encoders: libx265 nvenc_hevc hevc_nvenc hevc_v4l2m2m )
 ...



-
How to use ffmpeg to change the h264 properties, yuv, fps, tbr, tbn, and tbc of an mp4 file ?
23 août 2020, par bguizUsing ffmpeg, I would like to convert a video file such that its video stream changes like so :


- 

- Current video stream :
Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 2560x1080 [SAR 4:3 DAR 256:81], 60 kb/s, 15 fps, 15 tbr, 15360 tbn, 30 tbc (default)
- Target video stream :
Stream #0:0(und): Video: h264 (High 4:4:4 Predictive) (avc1 / 0x31637661), yuv444p, 2560x1080, 272 kb/s, 20 fps, 20 tbr, 10240 tbn, 40 tbc (default)






(values that differ : h264 properties, yuv, fps, tbr, tbn, and tbc)


... and its audio stream changes like so :


- 

- Current audio stream :
Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 191 kb/s (default)
- Target audio stream :
Stream #0:1(und): Audio: aac (mp4a / 0x6134706D), 48000 Hz, mono, fltp, 69 kb/s (default)






(values that differ : aac properties)


How can I do this ?



Detailed version


I would like to be able to concatenate, without re-encoding,
main.mp4
, followed byoutro.mp4
, using the following commands :

echo "file 'main.mp4'" > concat.txt
echo "file 'outro.mp4'" >> concat.txt
ffmpeg \
 -f concat \
 -safe 0 \
 -i concat.txt \
 -c copy \
 concat.mp4



What results is a file which plays till the end of
main.mp4
, and then the video freezes, and I hear the audio ofoutro.mp4
. The same video frame then stays on, with no sound, for an extra 30 minutes (end time shown in VLC).

My assumption is that these files are incompatible with each other in some way that prevents them from being concatenated using
-codec copy
(without re-encoding).

Here is the
ffprobe
output formain.mp4
:

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'main.mp4':
 Metadata:
 major_brand : isom
 minor_version : 512
 compatible_brands: isomiso2avc1mp41
 encoder : Lavf58.45.100
 Duration: 01:13:00.65, start: 0.000000, bitrate: 348 kb/s
 Stream #0:0(und): Video: h264 (High 4:4:4 Predictive) (avc1 / 0x31637661), yuv444p, 2560x1080, 272 kb/s, 20 fps, 20 tbr, 10240 tbn, 40 tbc (default)
 Metadata:
 handler_name : VideoHandler
 Stream #0:1(und): Audio: aac (mp4a / 0x6134706D), 48000 Hz, mono, fltp, 69 kb/s (default)
 Metadata:
 handler_name : SoundHandler



Here is the
ffprobe
output foroutro.mp4
:

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'outro.mp4':
 Metadata:
 major_brand : isom
 minor_version : 512
 compatible_brands: isomiso2avc1mp41
 encoder : Lavf58.45.100
 Duration: 00:00:04.12, start: 0.000000, bitrate: 254 kb/s
 Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 2560x1080 [SAR 4:3 DAR 256:81], 60 kb/s, 15 fps, 15 tbr, 15360 tbn, 30 tbc (default)
 Metadata:
 handler_name : VideoHandler
 Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 191 kb/s (default)
 Metadata:
 handler_name : Stereo



How can I convert
outro.mp4
, such that I may concatenate the files without re-encoding ?

Note that I am OK with re-encoding the
outro.mp4
on its own,
I simply want to avoid re-encoding during the concatenation step,
and avoid re-encodingmain.mp4
.


ffmpeg build


$ ffmpeg -version
ffmpeg version 4.3-2~18.04.york0 Copyright (c) 2000-2020 the FFmpeg developers
built with gcc 7 (Ubuntu 7.5.0-3ubuntu1~18.04)
configuration: --prefix=/usr --extra-version='2~18.04.york0' --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librabbitmq --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-pocketsphinx --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared
libavutil 56. 51.100 / 56. 51.100
libavcodec 58. 91.100 / 58. 91.100
libavformat 58. 45.100 / 58. 45.100
libavdevice 58. 10.100 / 58. 10.100
libavfilter 7. 85.100 / 7. 85.100
libavresample 4. 0. 0 / 4. 0. 0
libswscale 5. 7.100 / 5. 7.100
libswresample 3. 7.100 / 3. 7.100
libpostproc 55. 7.100 / 55. 7.100



- Current video stream :