
Recherche avancée
Médias (91)
-
Collections - Formulaire de création rapide
19 février 2013, par
Mis à jour : Février 2013
Langue : français
Type : Image
-
Les Miserables
4 juin 2012, par
Mis à jour : Février 2013
Langue : English
Type : Texte
-
Ne pas afficher certaines informations : page d’accueil
23 novembre 2011, par
Mis à jour : Novembre 2011
Langue : français
Type : Image
-
The Great Big Beautiful Tomorrow
28 octobre 2011, par
Mis à jour : Octobre 2011
Langue : English
Type : Texte
-
Richard Stallman et la révolution du logiciel libre - Une biographie autorisée (version epub)
28 octobre 2011, par
Mis à jour : Octobre 2011
Langue : English
Type : Texte
-
Rennes Emotion Map 2010-11
19 octobre 2011, par
Mis à jour : Juillet 2013
Langue : français
Type : Texte
Autres articles (46)
-
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. -
Support audio et vidéo HTML5
10 avril 2011MediaSPIP utilise les balises HTML5 video et audio pour la lecture de documents multimedia en profitant des dernières innovations du W3C supportées par les navigateurs modernes.
Pour les navigateurs plus anciens, le lecteur flash Flowplayer est utilisé.
Le lecteur HTML5 utilisé a été spécifiquement créé pour MediaSPIP : il est complètement modifiable graphiquement pour correspondre à un thème choisi.
Ces technologies permettent de distribuer vidéo et son à la fois sur des ordinateurs conventionnels (...) -
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 (7319)
-
Merge two videos with different HTTP Range header bytes
5 avril 2022, par Mohammad MomeniI want to save 10 seconds from any part of a video by using its URL (without downloading it completely).
the server supports the
Range
header and it's possible to get specific byte ranges, the video is ok when I save it with something likeRange: bytes=0-102400
but when I change the start byte and save a video withRange: bytes=307200-614400
it's no longer playable.

I know maybe it lacks a MIME/header type that should be at the beginning of a file, but the first bytes are not in this response to specify the correct format of the file.
so I saved the video from 0-102400, which is ok and playable, and wanted to get that specific range and somehow append it after the first file to have both a correct file header (less than 1 sec) and that middle part of the video.


first.webm
Range : bytes=0-102400 (valid playable file)

middle.webm
Range : bytes=307200-614400 (not playable file)

I tried to merge them using this command recommended by this answer


ffmpeg -f concat -i list.txt -c copy merged.webm



logs :


[matroska,webm @ 000002143c3e77c0] File ended prematurely00 bitrate=3752.0kbits/s speed=N/A
[matroska,webm @ 000002143c429e40] Format matroska,webm detected only with low score of 1, misdetection possible!
[matroska,webm @ 000002143c429e40] EBML header parsing failed
[concat @ 000002143c3dda80] Impossible to open 'middle.webm'
list.txt: Invalid data found when processing input
frame= 42 fps=0.0 q=-1.0 Lsize= 10kB time=00:00:01.64 bitrate= 48.7kbits/s speed= 231x 
video:9kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 8.500000%



generated video only shows the first video (which was already playable before merging) and ends.
I inspired this idea from this answer and don't want to download the complete video. If I can't merge them is it possible and how to write a MIME/header for the
middle.webm
manually to make it a valid playable video ?

-
avcodec/ljpegenc : Allow full range yuv420p, yuv422p, yuv444p by default
6 avril 2021, par Andreas Rheinhardtavcodec/ljpegenc : Allow full range yuv420p, yuv422p, yuv444p by default
The documentation for AV_PIX_FMT_YUVJ420P reads :
"planar YUV 4:2:0, 12bpp, full scale (JPEG), deprecated in favor of
AV_PIX_FMT_YUV420P and setting color_range"
Yet the LJPEG encoder only accepts full scale yuv420p when strictness is
set to unofficial or lower ; with default strictness it emits a nonsense
error message that says that limit range YUV is unofficial. This has
been changed to allow full range yuv420p, yuv422p and yuv444p irrespective
of the level of strictness.Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
-
FFMPEG color range cropped to 15-235 in RGB
20 décembre 2017, par Some1ElseI have a series of BMPs (or PNG) images that I want to convert to XVID and MP5 movie formats.
Encoding works but the resulting movie has a washed out color look to it and the blacks are somehow moved to RGB 16 and the brightest 255 values are moved down to 235. I want the output movie to use the same 0 to 255 colors as the source frames.
Now there are all sorts of conflicting doco out there for FFMPEG so I am hopinbg someone has an example command line that does what I need. I have tried all sorts of pix_fmt flags but none of them get the output movie in the full color range.
For XVID
ffmpeg.exe -framerate 60 -i "D:\SRC%05d.BMP" -c:v mpeg4 -vtag xvid -qscale 1 -y "D:\OUTPUT.AVI""
For H265
ffmpeg.exe -framerate 60 -i "D:\SRC%05d.BMP" -c:v libx265 -x265-params lossless=1 -s 3840x2160 -pix_fmt yuvj420p -an -y "D:\OUTPUT.MP4""
The yuvj420p is supposed to give the full color range but ffmpeg complains "Incompatible pixel format ’yuvj420p’ for codec ’libx265’, auto-selecting format ’yuv420p’"
So, are there any FFMPEG gurus out there that can give me the magic switches to get my output movies with black blacks and colors that maintain the original frame files 0-255 RGB values.