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Revolution of Open-source and film making towards open film making
6 octobre 2011, par
Mis à jour : Juillet 2013
Langue : English
Type : Texte
Autres articles (111)
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Participer à sa traduction
10 avril 2011Vous pouvez nous aider à améliorer les locutions utilisées dans le logiciel ou à traduire celui-ci dans n’importe qu’elle nouvelle langue permettant sa diffusion à de nouvelles communautés linguistiques.
Pour ce faire, on utilise l’interface de traduction de SPIP où l’ensemble des modules de langue de MediaSPIP sont à disposition. ll vous suffit de vous inscrire sur la liste de discussion des traducteurs pour demander plus d’informations.
Actuellement MediaSPIP n’est disponible qu’en français et (...) -
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 (...) -
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 (14039)
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Resizing AVIF images with transparency with FFmpeg [closed]
4 octobre 2024, par CalebmerI'm trying to resize an image with transparency with FFmpeg, however the output looks to only be a resized version of the alpha layer.


When I try to do a noop transform of the AVIF image with an alpha layer :


ffmpeg -i input.avif output.avif



output.avif
appears to be the alpha layer with black representing alpha 0 and white representing alpha 1.

ffprobe input.avif
gives me :

ffprobe version 7.0.2 Copyright (c) 2007-2024 the FFmpeg developers
 built with Apple clang version 15.0.0 (clang-1500.3.9.4)
 configuration: --prefix=/opt/homebrew/Cellar/ffmpeg/7.0.2 --enable-shared --enable-pthreads --enable-version3 --cc=clang --host-cflags= --host-ldflags='-Wl,-ld_classic' --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libaribb24 --enable-libbluray --enable-libdav1d --enable-libharfbuzz --enable-libjxl --enable-libmp3lame --enable-libopus --enable-librav1e --enable-librist --enable-librubberband --enable-libsnappy --enable-libsrt --enable-libssh --enable-libsvtav1 --enable-libtesseract --enable-libtheora --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libspeex --enable-libsoxr --enable-libzmq --enable-libzimg --disable-libjack --disable-indev=jack --enable-videotoolbox --enable-audiotoolbox --enable-neon
 libavutil 59. 8.100 / 59. 8.100
 libavcodec 61. 3.100 / 61. 3.100
 libavformat 61. 1.100 / 61. 1.100
 libavdevice 61. 1.100 / 61. 1.100
 libavfilter 10. 1.100 / 10. 1.100
 libswscale 8. 1.100 / 8. 1.100
 libswresample 5. 1.100 / 5. 1.100
 libpostproc 58. 1.100 / 58. 1.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'input.avif':
 Metadata:
 major_brand : avif
 minor_version : 0
 compatible_brands: avifmif1miaf
 Duration: N/A, start: 0.000000, bitrate: N/A
 Stream #0:0[0x1]: Video: av1 (libdav1d) (Main) (av01 / 0x31307661), gray(pc), 336x252 [SAR 1:1 DAR 4:3], 1 fps, 1 tbr, 1 tbn (default)
 Stream #0:1[0x2]: Video: av1 (libdav1d) (High) (av01 / 0x31307661), yuv444p(pc, smpte170m/bt709/iec61966-2-1), 336x252 [SAR 1:1 DAR 4:3], 1 fps, 1 tbr, 1 tbn



Seeing there are two streams (the first stream being
gray(pc)
, probably the alpha layer) I next tried :

ffmpeg -i input.avif -map 0:v:1 output.avif



To see the second stream and it gave me the image without any alpha channel. Transparent pixels were black.


Ultimately I want to resize the AVIF file with
ffmpeg -i input.avif -vf "scale=iw/2:-1" output.avif
but that appears to only resize the greyscale alpha channel. Furthermore, this will be part of a script that operates on some AVIF files without an alpha channel and some AVIF files with an alpha channel and I don't know which files have an alpha channel ahead of time.ffmpeg -i input.avif -vf "scale=iw/2:-1" output.avif
works for files without an alpha channel.

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avfilter : remove deprecated FF_API_LINK_PUBLIC
19 février, par James Almer -
Ffmpeg RTSP stream with size=N/A bitrate=N/A [closed]
6 octobre 2024, par ComycosWhen I try to stream a video it seems to work but bitrate and size are N/A
frame= 277 fps= 26 q=-1.0 size=N/A time=00:00:11.07 bitrate=N/A speed=1.05x


I run the following command to stream a video to a RTSP server :

ffmpeg -re -stream_loop -1 -i idurre-2024-09-17-12h33m19s.mp4 -c copy -f rtsp -rtsp_transport tcp rtsp://localhost:8554/test


The output ffmpeg is like this :


ffmpeg version 7.1 Copyright (c) 2000-2024 the FFmpeg developers
 built with Apple clang version 15.0.0 (clang-1500.1.0.2.5)
 configuration: --prefix=/opt/homebrew/Cellar/ffmpeg/7.1 --enable-shared --enable-pthreads --enable-version3 --cc=clang --host-cflags= --host-ldflags='-Wl,-ld_classic' --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libaribb24 --enable-libbluray --enable-libdav1d --enable-libharfbuzz --enable-libjxl --enable-libmp3lame --enable-libopus --enable-librav1e --enable-librist --enable-librubberband --enable-libsnappy --enable-libsrt --enable-libssh --enable-libsvtav1 --enable-libtesseract --enable-libtheora --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libspeex --enable-libsoxr --enable-libzmq --enable-libzimg --disable-libjack --disable-indev=jack --enable-videotoolbox --enable-audiotoolbox --enable-neon
 libavutil 59. 39.100 / 59. 39.100
 libavcodec 61. 19.100 / 61. 19.100
 libavformat 61. 7.100 / 61. 7.100
 libavdevice 61. 3.100 / 61. 3.100
 libavfilter 10. 4.100 / 10. 4.100
 libswscale 8. 3.100 / 8. 3.100
 libswresample 5. 3.100 / 5. 3.100
 libpostproc 58. 3.100 / 58. 3.100
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x127704880] st: 0 edit list: 1 Missing key frame while searching for timestamp: 0
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x127704880] st: 0 edit list 1 Cannot find an index entry before timestamp: 0.
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'idurre-2024-09-17-12h33m19s.mp4':
 Metadata:
 major_brand : isom
 minor_version : 0
 compatible_brands: mp41avc1
 creation_time : 2024-09-17T10:34:16.000000Z
 encoder : vlc 3.0.21 stream output
 encoder-eng : vlc 3.0.21 stream output
 Duration: 00:00:55.68, start: 0.000000, bitrate: 16205 kb/s
 Stream #0:0[0x1](eng): Video: h264 (High) (avc1 / 0x31637661), yuvj420p(pc, bt709, progressive), 1920x1080, 16203 kb/s, 25 fps, 25 tbr, 1000k tbn (default)
 Metadata:
 creation_time : 2024-09-17T10:34:16.000000Z
 handler_name : VideoHandler
 vendor_id : [0][0][0][0]
Stream mapping:
 Stream #0:0 -> #0:0 (copy)
Output #0, rtsp, to 'rtsp://localhost:8554/test':
 Metadata:
 major_brand : isom
 minor_version : 0
 compatible_brands: mp41avc1
 encoder : Lavf61.7.100
 Stream #0:0(eng): Video: h264 (High) (avc1 / 0x31637661), yuvj420p(pc, bt709, progressive), 1920x1080, q=2-31, 16203 kb/s, 25 fps, 25 tbr, 90k tbn (default)
 Metadata:
 creation_time : 2024-09-17T10:34:16.000000Z
 handler_name : VideoHandler
 vendor_id : [0][0][0][0]
Press [q] to stop, [?] for help
frame= 516 fps= 26 q=-1.0 size=N/A time=00:00:20.63 bitrate=N/A speed=1.03x 

[q] command received. Exiting.

[out#0/rtsp @ 0x6000008e0240] video:40672KiB audio:0KiB subtitle:0KiB other streams:0KiB global headers:0KiB muxing overhead: unknown
frame= 528 fps= 26 q=-1.0 Lsize=N/A time=00:00:21.11 bitrate=N/A speed=1.02x 



The server I'm streaming to is a MediaMTX which is supposed to receive the stream. It seems to be connected as it logs it :


mediamtx-rtsp | 2024/10/06 10:35:13 INF MediaMTX v1.9.0
mediamtx-rtsp | 2024/10/06 10:35:13 INF configuration loaded from /mediamtx.yml
mediamtx-rtsp | 2024/10/06 10:35:13 INF [RTSP] listener opened on :8554 (TCP), :8000 (UDP/RTP), :8001 (UDP/RTCP)
mediamtx-rtsp | 2024/10/06 10:35:13 INF [SRT] listener opened on :8890 (UDP)
mediamtx-rtsp | 2024/10/06 10:35:16 INF [RTSP] [conn 192.168.65.1:17069] opened
mediamtx-rtsp | 2024/10/06 10:35:16 INF [RTSP] [session b3bb2623] created by 192.168.65.1:17069
mediamtx-rtsp | 2024/10/06 10:35:16 INF [RTSP] [session b3bb2623] is publishing to path 'test', 1 track (H264)



But when I try to read it with ffplay nothing is showing...