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La file d’attente de SPIPmotion
28 novembre 2010, parUne file d’attente stockée dans la base de donnée
Lors de son installation, SPIPmotion crée une nouvelle table dans la base de donnée intitulée spip_spipmotion_attentes.
Cette nouvelle table est constituée des champs suivants : id_spipmotion_attente, l’identifiant numérique unique de la tâche à traiter ; id_document, l’identifiant numérique du document original à encoder ; id_objet l’identifiant unique de l’objet auquel le document encodé devra être attaché automatiquement ; objet, le type d’objet auquel (...) -
Use, discuss, criticize
13 avril 2011, parTalk 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. -
Des sites réalisés avec MediaSPIP
2 mai 2011, parCette page présente quelques-uns des sites fonctionnant sous MediaSPIP.
Vous pouvez bien entendu ajouter le votre grâce au formulaire en bas de page.
Sur d’autres sites (7756)
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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...