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Matmos - Action at a Distance
15 septembre 2011, par
Mis à jour : Septembre 2011
Langue : English
Type : Audio
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DJ Dolores - Oslodum 2004 (includes (cc) sample of “Oslodum” by Gilberto Gil)
15 septembre 2011, par
Mis à jour : Septembre 2011
Langue : English
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Danger Mouse & Jemini - What U Sittin’ On ? (starring Cee Lo and Tha Alkaholiks)
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Mis à jour : Septembre 2011
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Cornelius - Wataridori 2
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The Rapture - Sister Saviour (Blackstrobe Remix)
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Chuck D with Fine Arts Militia - No Meaning No
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Autres articles (62)
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MediaSPIP v0.2
21 juin 2013, parMediaSPIP 0.2 est la première version de MediaSPIP stable.
Sa date de sortie officielle est le 21 juin 2013 et est annoncée ici.
Le fichier zip ici présent contient uniquement les sources de MediaSPIP en version standalone.
Comme pour la version précédente, il est nécessaire d’installer manuellement l’ensemble des dépendances logicielles sur le serveur.
Si vous souhaitez utiliser cette archive pour une installation en mode ferme, il vous faudra également procéder à d’autres modifications (...) -
MediaSPIP version 0.1 Beta
16 avril 2011, parMediaSPIP 0.1 beta est la première version de MediaSPIP décrétée comme "utilisable".
Le fichier zip ici présent contient uniquement les sources de MediaSPIP en version standalone.
Pour avoir une installation fonctionnelle, il est nécessaire d’installer manuellement l’ensemble des dépendances logicielles sur le serveur.
Si vous souhaitez utiliser cette archive pour une installation en mode ferme, il vous faudra également procéder à d’autres modifications (...) -
Les autorisations surchargées par les plugins
27 avril 2010, parMediaspip core
autoriser_auteur_modifier() afin que les visiteurs soient capables de modifier leurs informations sur la page d’auteurs
Sur d’autres sites (14189)
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ffmpeg : stream copy from .mxf into NLE-compatible format
9 juin 2013, par DavidBecause my NLE software does not support the .mxf-files from Canon XF100 I need to convert them into a supported format.
As far as I know, mxf-files are just another container format for mpeg2 streams, so it would be really nice to extract the streams and place them into another container (without reencoding).
I think ffmpeg can do this – correct me if I'm wrong – by running the following command :
ffmpeg -i in.mxf -vcodec copy out.m2ts (or .ts, .mts, ...)
ffmpeg finishes without errors after about 2 seconds (in.mxf is abut 170mb) :
c:\video>c:\ffmpeg\bin\ffmpeg -i in.MXF -vcodec copy out.m2ts
ffmpeg version N-53680-g0ab9362 Copyright (c) 2000-2013 the FFmpeg developers
built on May 30 2013 12:14:03 with gcc 4.7.3 (GCC)
configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-av
isynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enab
le-iconv --enable-libass --enable-libbluray --enable-libcaca --enable-libfreetyp
e --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --ena
ble-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-l
ibopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libsp
eex --enable-libtheora --enable-libtwolame --enable-libvo-aacenc --enable-libvo-
amrwbenc --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --
enable-libxvid --enable-zlib
libavutil 52. 34.100 / 52. 34.100
libavcodec 55. 12.102 / 55. 12.102
libavformat 55. 8.100 / 55. 8.100
libavdevice 55. 2.100 / 55. 2.100
libavfilter 3. 73.100 / 3. 73.100
libswscale 2. 3.100 / 2. 3.100
libswresample 0. 17.102 / 0. 17.102
libpostproc 52. 3.100 / 52. 3.100
Guessed Channel Layout for Input Stream #0.1 : mono
Guessed Channel Layout for Input Stream #0.2 : mono
Input #0, mxf, from 'in.MXF':
Metadata:
uid : 1bb23c97-6205-4800-80a2-e00002244ba7
generation_uid : 1bb23c97-6205-4800-8122-e00002244ba7
company_name : CANON
product_name : XF100
product_version : 1.00
product_uid : 060e2b34-0401-010d-0e15-005658460100
modification_date: 2013-01-06 11:05:02
timecode : 01:42:14:22
Duration: 00:00:28.32, start: 0.000000, bitrate: 51811 kb/s
Stream #0:0: Video: mpeg2video (4:2:2), yuv422p, 1920x1080 [SAR 1:1 DAR 16:9
], 25 fps, 25 tbr, 25 tbn, 50 tbc
Stream #0:1: Audio: pcm_s16le, 48000 Hz, mono, s16, 768 kb/s
Stream #0:2: Audio: pcm_s16le, 48000 Hz, mono, s16, 768 kb/s
Output #0, mpegts, to 'out.m2ts':
Metadata:
uid : 1bb23c97-6205-4800-80a2-e00002244ba7
generation_uid : 1bb23c97-6205-4800-8122-e00002244ba7
company_name : CANON
product_name : XF100
product_version : 1.00
product_uid : 060e2b34-0401-010d-0e15-005658460100
modification_date: 2013-01-06 11:05:02
timecode : 01:42:14:22
encoder : Lavf55.8.100
Stream #0:0: Video: mpeg2video, yuv422p, 1920x1080 [SAR 1:1 DAR 16:9], q=2-3
1, 25 fps, 90k tbn, 25 tbc
Stream #0:1: Audio: mp2, 48000 Hz, mono, s16, 128 kb/s
Stream mapping:
Stream #0:0 -> #0:0 (copy)
Stream #0:1 -> #0:1 (pcm_s16le -> mp2)
Press [q] to stop, [?] for help
frame= 532 fps=0.0 q=-1.0 size= 143511kB time=00:00:21.25 bitrate=55314.1kbits
frame= 561 fps=435 q=-1.0 size= 151254kB time=00:00:22.42 bitrate=55242.0kbits
frame= 586 fps=314 q=-1.0 size= 158021kB time=00:00:23.41 bitrate=55288.0kbits
frame= 609 fps=255 q=-1.0 size= 164182kB time=00:00:24.34 bitrate=55235.4kbits
frame= 636 fps=217 q=-1.0 size= 171463kB time=00:00:25.42 bitrate=55235.1kbits
frame= 669 fps=194 q=-1.0 size= 180133kB time=00:00:26.72 bitrate=55226.3kbits
frame= 699 fps=173 q=-1.0 size= 188326kB time=00:00:27.92 bitrate=55256.6kbits
frame= 708 fps=169 q=-1.0 Lsize= 190877kB time=00:00:28.30 bitrate=55233.6kbit
s/s
video:172852kB audio:442kB subtitle:0 global headers:0kB muxing overhead 10.1461
18%Unfortunately the output file turns out to be displayed correctly only by vlc player.
My NLE-software (Cyberlink Power Director) is able to open the file but most of the picture is green. Only a few pixels on the left edge show the original video :Any ideas how to solve that problem ? Is there a better way to use .mxf-files in NLE-software without native support ?
thanks in advance
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Need help configuring FFMPEG to work with a webcams h264 stream
9 août 2020, par The Welsh DragonI have been trying to get a H264 stream from a H264 usb webcam working but I am not making much progress so I'm hoping someone knows FFMPEG better than me !


There are dozens of questions/answers on SO but none solve my problem.


In short, I get a very pixelated (or sometimes mostly green) screen. I am using VLC to test the stream which is coming via an RTSP server. I am using FFMPEG to copy the webcam stream to the local RTSP server.


The webcam also supports YUYV which I can get working - it is just the h264 stream causing me problems.


So this is how the device is presented :


H264 USB Camera: USB Camera (usb-20980000.usb-1):
 /dev/video0
 /dev/video1
 /dev/video2
 /dev/video3



/dev/video0 is the YUYV and MPEG stream
/dev/video2 is the h264 stream that has the following capabilities :


ioctl: VIDIOC_ENUM_FMT
 Type: Video Capture

 [0]: 'H264' (H.264, compressed)
 Size: Discrete 1920x1080
 Interval: Discrete 0.033s (30.000 fps)
 Interval: Discrete 0.040s (25.000 fps)
 Interval: Discrete 0.067s (15.000 fps)
 Interval: Discrete 0.033s (30.000 fps)
 Interval: Discrete 0.040s (25.000 fps)
 Interval: Discrete 0.067s (15.000 fps)
 Size: Discrete 1280x720
 Interval: Discrete 0.033s (30.000 fps)
 Interval: Discrete 0.040s (25.000 fps)
 Interval: Discrete 0.067s (15.000 fps)
 Size: Discrete 800x600
 Interval: Discrete 0.033s (30.000 fps)
 Interval: Discrete 0.040s (25.000 fps)
 Interval: Discrete 0.067s (15.000 fps)
 Size: Discrete 640x480
 Interval: Discrete 0.033s (30.000 fps)
 Interval: Discrete 0.040s (25.000 fps)
 Interval: Discrete 0.067s (15.000 fps)
 Size: Discrete 640x360
 Interval: Discrete 0.033s (30.000 fps)
 Interval: Discrete 0.040s (25.000 fps)
 Interval: Discrete 0.067s (15.000 fps)
 Size: Discrete 352x288
 Interval: Discrete 0.033s (30.000 fps)
 Interval: Discrete 0.040s (25.000 fps)
 Interval: Discrete 0.067s (15.000 fps)
 Size: Discrete 320x240
 Interval: Discrete 0.033s (30.000 fps)
 Interval: Discrete 0.040s (25.000 fps)
 Interval: Discrete 0.067s (15.000 fps)
 Size: Discrete 1920x1080
 Interval: Discrete 0.033s (30.000 fps)
 Interval: Discrete 0.040s (25.000 fps)
 Interval: Discrete 0.067s (15.000 fps)
 Interval: Discrete 0.033s (30.000 fps)
 Interval: Discrete 0.040s (25.000 fps)
 Interval: Discrete 0.067s (15.000 fps)



I have tried various resolutions, the smaller giving slightly less pixelated images but none are usable and definitely dont compare to the YUYV high resolution results.


This (YUYV) command works :


ffmpeg -input_format yuyv422 -f video4linux2 -s 1280x720 -r 10 -i /dev/video0 -c:v h264_omx -r 10 -b:v 2M -an -f rtsp rtsp://localhost:80/live/stream



These two h264 options dont work :


ffmpeg -input_format h264 -f video4linux2 -video_size 1920x1080 -framerate 30 -i /dev/video0 -c:v copy -an -f rtsp rtsp://localhost:80/live/stream



ffmpeg -re -i /dev/video2 -video_size 800x600 -framerate 15 -pix_fmt yuv420p -tune zerolatency -c:v copy -an -f rtsp rtsp://localhost:80/live/stream



For that last command the FFMPEG output looks like this :


ffmpeg version git-2020-08-07-6fdf3cc Copyright (c) 2000-2020 the FFmpeg developers
 built with gcc 8 (Raspbian 8.3.0-6+rpi1)
 configuration: --extra-ldflags=-latomic --arch=armel --target-os=linux --enable-gpl --enable-omx --enable-omx-rpi --enable-nonfree --enable-libfreetype --enable-libx264 --enable-libmp3lame --enable-mmal --enable-indev=alsa --enable-outdev=alsa
 libavutil 56. 58.100 / 56. 58.100
 libavcodec 58.100.100 / 58.100.100
 libavformat 58. 50.100 / 58. 50.100
 libavdevice 58. 11.101 / 58. 11.101
 libavfilter 7. 87.100 / 7. 87.100
 libswscale 5. 8.100 / 5. 8.100
 libswresample 3. 8.100 / 3. 8.100
 libpostproc 55. 8.100 / 55. 8.100
Input #0, video4linux2,v4l2, from '/dev/video2':
 Duration: N/A, start: 1353.265049, bitrate: N/A
 Stream #0:0: Video: h264 (Main), yuv420p(progressive), 1920x1080, 30 fps, 30 tbr, 1000k tbn, 2000k tbc
[udp @ 0x38c29f0] attempted to set receive buffer to size 393216 but it only ended up set as 360448
[udp @ 0x38d7b50] attempted to set receive buffer to size 393216 but it only ended up set as 360448
Output #0, rtsp, to 'rtsp://localhost:80/live/stream':
 Metadata:
 encoder : Lavf58.50.100
 Stream #0:0: Video: h264 (Main), yuv420p(progressive), 1920x1080, q=2-31, 30 fps, 30 tbr, 90k tbn, 1000k tbc
Stream mapping:
 Stream #0:0 -> #0:0 (copy)
Press [q] to stop, [?] for help
[rtsp @ 0x38fd890] Timestamps are unset in a packet for stream 0. This is deprecated and will stop working in the future. Fix your code to set the timestamps properly
[rtsp @ 0x38fd890] Non-monotonous DTS in output stream 0:0; previous: 0, current: 0; changing to 1. This may result in incorrect timestamps in the output file.
frame= 348 fps= 18 q=-1.0 size=N/A time=00:00:21.03 bitrate=N/A speed=1.09x



The issue looks like it is bandwidth related or the lack of processing power in the device being used BUT the YUYV works at a high resolution and (taking a completely different approach i.e. not using FFMPEG) I can get a very decent MPEG stream working on the same device.


So any FFMPEG experts out there who can help me with getting the correct parameters for a h264 stream ?


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Google’s YouTube Uses FFmpeg
9 février 2011, par Multimedia Mike — GeneralControversy arose last week when Google accused Microsoft of stealing search engine results for their Bing search engine. It was a pretty novel sting operation and Google did a good job of visually illustrating their side of the story on their official blog.
This reminds me of the fact that Google’s YouTube video hosting site uses FFmpeg for converting videos. Not that this is in the same league as the search engine shenanigans (it’s perfectly legit to use FFmpeg in this capacity, but to my knowledge, Google/YouTube has never confirmed FFmpeg usage), but I thought I would revisit this item and illustrate it with screenshots. This is not new information— I first empirically tested this fact 4 years ago. However, a lot of people wonder how exactly I can identify FFmpeg on the backend when I claim that I’ve written code that helps power YouTube.
Short Answer
How do I know YouTube uses FFmpeg to convert multimedia ? Because :- FFmpeg can decode a number of impossibly obscure multimedia formats using code I wrote
- YouTube can transcode many of the same formats
- I screwed up when I wrote the code to support some of these weird formats
- My mistakes are still present when YouTube transcodes certain fringe formats
Longer Answer (With Pictures !)
Let’s take a video format named RoQ, developed by noted game designer Graeme Devine. Originated for use in the FMV-heavy game The 11th Hour, the format eventually found its way into the Quake 3 engine as well as many games derived from the same technology.Dr. Tim Ferguson reverse engineered the format (though it would later be open sourced along with the rest of the Q3 engine). I wrote a RoQ playback system for FFmpeg, and I messed up in doing so. I believe my coding error helps demonstrate the case I’m trying to make here.
Observe what happened when I pushed the jk02.roq sample through YouTube in my original experiment 4 years ago :
Do you see how the canyon walls bleed into the sky ? That’s not supposed to happen. FFmpeg doesn’t do that anymore but I was able to go back into the source code history to find when it did do that :
Academic Answer
FFmpeg fixed this bug in June of 2007 (thanks to Eric Lasota). The problem had to do with premature colorspace conversion in my original decoder.Leftovers
I tried uploading the video again to see if the problem persists in YouTube’s transcoder. First bit of trivia : YouTube detects when you have uploaded the same video twice and rejects the subsequent attempts. So I created a double concatenation of the video and uploaded it. The problem is gone, illustrating that the backend is actually using a newer version of FFmpeg. This surprises me for somewhat esoteric reasons.Here’s another interesting bit of trivia for those who don’t do a lot of YouTube uploading— YouTube reports format details when you upload a video :
So, yep, RoQ format. And you can wager that this will prompt me to go back through the litany of unusual formats that FFmpeg supports to see how YouTube responds.