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Médias (2)
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Core Media Video
4 avril 2013, par
Mis à jour : Juin 2013
Langue : français
Type : Video
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Video d’abeille en portrait
14 mai 2011, par
Mis à jour : Février 2012
Langue : français
Type : Video
Autres articles (105)
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Multilang : améliorer l’interface pour les blocs multilingues
18 février 2011, parMultilang est un plugin supplémentaire qui n’est pas activé par défaut lors de l’initialisation de MediaSPIP.
Après son activation, une préconfiguration est mise en place automatiquement par MediaSPIP init permettant à la nouvelle fonctionnalité d’être automatiquement opérationnelle. Il n’est donc pas obligatoire de passer par une étape de configuration pour cela. -
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. -
Keeping control of your media in your hands
13 avril 2011, parThe vocabulary used on this site and around MediaSPIP in general, aims to avoid reference to Web 2.0 and the companies that profit from media-sharing.
While using MediaSPIP, you are invited to avoid using words like "Brand", "Cloud" and "Market".
MediaSPIP is designed to facilitate the sharing of creative media online, while allowing authors to retain complete control of their work.
MediaSPIP aims to be accessible to as many people as possible and development is based on expanding the (...)
Sur d’autres sites (11400)
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Announcing the first free software Blu-ray encoder
For many years it has been possible to make your own DVDs with free software tools. Over the course of the past decade, DVD creation evolved from the exclusive domain of the media publishing companies to something basically anyone could do on their home computer.
But Blu-ray has yet to get that treatment. Despite the “format war” between Blu-ray and HD DVD ending over two years ago, free software has lagged behind. “Professional” tools for Blu-ray video encoding can cost as much as $100,000 and are often utter garbage. Here are two actual screenshots from real Blu-rays : I wish I was making this up.
But today, things change. Today we take the first step towards a free software Blu-ray creation toolkit.
Thanks to tireless work by Kieran Kunyha, Alex Giladi, Lamont Alston, and the Doom9 crowd, x264 can now produce Blu-ray-compliant video. Extra special thanks to The Criterion Collection for sponsoring the final compliance test to confirm x264′s Blu-ray compliance.
With x264′s powerful compression, as demonstrated by the incredibly popular BD-Rebuilder Blu-ray backup software, it’s quite possible to author Blu-ray disks on DVD9s (dual-layer DVDs) or even DVD5s (single-layer DVDs) with a reasonable level of quality. With a free software encoder and less need for an expensive Blu-ray burner, we are one step closer to putting HD optical media creation in the hands of the everyday user.
To celebrate this achievement, we are making available for download a demo Blu-ray encoded with x264, containing entirely free content !
On this Blu-ray are the Open Movie Project films Big Buck Bunny and Elephant’s Dream, available under a Creative Commons license. Additionally, Microsoft has graciously provided about 6 minutes of lossless HD video and audio (from part of a documentary project) under a very liberal license. This footage rounds out the Blu-ray by adding some difficult live-action content in addition to the relatively compressible CGI footage from the Open Movie Project. Finally, we used this sound sample, available under a Creative Commons license.
You may notice that the Blu-ray image is only just over 2GB. This is intentional ; we have encoded all the content on the disk at appropriate bitrates to be playable from an ordinary 4.7GB DVD. This should make it far easier to burn a copy of the Blu-ray, since Blu-ray burners and writable media are still relatively rare. Most Blu-ray players will treat a DVD containing Blu-ray data as a normal Blu-ray disc. A few, such as the Playstation 3, will not, but you can still play it as a data disc.
Finally, note that (in accordance with the Blu-ray spec) the disc image file uses the UDF 2.5 filesystem, which may be incompatible with some older virtual drive and DVD burning applications. You’ll also need to play it on an actual Blu-ray player if you want to get the menus and such working correctly. If you’re looking to play it on a PC, a free trial of Arcsoft TMT is available here.
What are you waiting for ? Grab a copy today !
UPDATE : Here is an AVCHD-compliant version of the above, which should work better when burned on a DVD-5 instead of a BD-R. (mirror)
What’s left before we have a fully free software Blu-ray creation toolkit ? Audio is already dealt with ; AC3 audio (aka Dolby Digital), the format used in DVD, is still supported by Blu-ray, and there are many free software AC3 encoders. The primary missing application is a free software Blu-ray authoring tool, to combine the video and audio streams to create a Blu-ray file structure with the menus, chapters, and so forth that we have all come to expect. But the hardest part is dealt with : we can now create compatible video and audio streams.
In the meantime, x264 can be used to create streams to be authored using Blu-Print, Scenarist, Encore or other commercial authoring tools.
More detailed documentation on the new Blu-ray support and how to use it can be found in the official commit message. Do keep in mind that you have to export to raw H.264 (not MKV or MP4) or else the buffering information will be slightly incorrect. Finally, also note that the encoding settings given as an example are not a good choice for general-purpose encoding : they are intentionally crippled by Blu-ray restrictions, which will significantly reduce compression for ordinary non-Blu-ray encoding.
In addition to Blu-ray support, the aforementioned commit comes with a lot of fun extras :
x264 now has native variable-framerate ratecontrol, which makes sure your encodes get a correct target bitrate and proper limiting of maximum bitrate even if the duration of every frame is different and the “framerate” is completely unknown. This helps a lot when encoding from variable-framerate container formats such as FLV and WMV, along with variable-framerate content such as anime.
x264 now supports pulldown (telecine) in much the same fashion as it is handled in MPEG-2. The calling application can pass in flags representing how to display a frame, allowing easy transcoding from MPEG-2 sources with pulldown, such as broadcast television. The x264 commandline app contains some examples of these (such as the common 3:2 pulldown pattern).
x264 now also exports HRD timing information, which is critical for compliant transport stream muxing. There is currently an active project to write a fully DVB-compatible free software TS muxer that will be able to interface with x264 for a seamless free software broadcast system. It will likely also be possible to repurpose this muxer as part of a free software Blu-ray authoring package.
All of this is now available in the latest x264.
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Increasing Website Traffic : 11 Tips To Attract Visitors
25 août 2023, par Erin — Analytics Tips, Marketing -
FFMPEG ALSA xrun crash
13 décembre 2017, par Liam MartensI’m running a YouTube RTMP stream using FFMPEG with x11grab and an alsa loopback device but sometimes after let’s say 20 hours there is an ALSA xrun and then the ffmpeg command crashes, but I’m not sure why or how this happens. (mind you the ffmpeg command does not run continuously it gets restarted automatically every so often, but the xrun makes the command crash causing the stream to go offline sometimes because a crash restart is not fast enough)
I’m using
thread_queue_size
and I’ve even manually compiled ffmpeg with a higherALSA BUFFER SIZE
, but the issue appears to persist still. Besides this I’ve also scoured many posts with people having similar issues but these never really seem to end up resolved.This is the stream command
ffmpeg -loglevel verbose -f alsa -thread_queue_size 12288 -ac 2 -i hw:Loopback,1,0 \
-probesize 10M -f x11grab -field_order tt -thread_queue_size 12288 -video_size 1280x720 -r 30 -i :1.1 \
-c:v libx264 -c:a libmp3lame -shortest -tune fastdecode -tune zerolatency \
-crf 26 -pix_fmt yuv420p -threads 0 -maxrate 2500k -bufsize 2500k -pass 1 -af aresample=async=1 \
-movflags +faststart -flags +global_header -preset ultrafast -r 30 -g 60 -b:v 2000k -b:a 192k -ar 44100 \
-f flv -rtmp_live live rtmp://a.rtmp.youtube.com/live2/{KEY}Log excerpt
ffmpeg version N-89463-gc7a5e80 Copyright (c) 2000-2017 the FFmpeg developers
built with gcc 6.3.0 (Debian 6.3.0-18) 20170516
configuration: --prefix=/usr --enable-avresample --enable-avfilter --enable-gpl --enable-libmp3lame --enable-librtmp --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libtheora --enable-postproc --enable-pic --enable-pthreads --enable-shared --disable-stripping --disable-static --enable-vaapi --enable-libopus --enable-libfreetype --enable-libfontconfig --enable-libpulse --disable-debug
libavutil 56. 5.100 / 56. 5.100
libavcodec 58. 6.103 / 58. 6.103
libavformat 58. 3.100 / 58. 3.100
libavdevice 58. 0.100 / 58. 0.100
libavfilter 7. 7.100 / 7. 7.100
libavresample 4. 0. 0 / 4. 0. 0
libswscale 5. 0.101 / 5. 0.101
libswresample 3. 0.101 / 3. 0.101
libpostproc 55. 0.100 / 55. 0.100
Guessed Channel Layout for Input Stream #0.0 : stereo
Input #0, alsa, from 'hw:Loopback,1,0':
Duration: N/A, start: 1513163617.594224, bitrate: 1536 kb/s
Stream #0:0: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
Input #1, x11grab, from ':1.1':
Duration: N/A, start: 1513163617.632434, bitrate: N/A
Stream #1:0: Video: rawvideo, 1 reference frame (BGR[0] / 0x524742), bgr0(top first), 854x480, 30 fps, 30 tbr, 1000k tbn, 1000k tbc
Parsing...
Parsed protocol: 0
Parsed host : a.rtmp.youtube.com
Parsed app : live2
RTMP_Connect1, ... connected, handshaking
HandShake: Type Answer : 03
HandShake: Server Uptime : 0
HandShake: FMS Version : 4.0.0.1
HandShake: Handshaking finished....
RTMP_Connect1, handshaked
Invoking connect
HandleServerBW: server BW = 2500000
HandleClientBW: client BW = 10000000 2
HandleChangeChunkSize, received: chunk size change to 256
RTMP_ClientPacket, received: invoke 240 bytes
(object begin)
Property:
Property:
Property:
(object begin)
Property: 3,5,3,824>
Property:
Property:
(object end)
Property:
(object begin)
Property:
Property:
Property:
Property:
Property:
(object begin)
Property:
(object end)
(object end)
(object end)
HandleInvoke, server invoking <_result>
HandleInvoke, received result for method call <connect>
Invoking releaseStream
Invoking FCPublish
Invoking createStream
RTMP_ClientPacket, received: invoke 21 bytes
(object begin)
Property:
Property:
Property: NULL
(object end)
HandleInvoke, server invoking <onbwdone>
Invoking _checkbw
RTMP_ClientPacket, received: invoke 29 bytes
(object begin)
Property:
Property:
Property: NULL
Property:
(object end)
HandleInvoke, server invoking <_result>
HandleInvoke, received result for method call <createstream>
Invoking publish
RTMP_ClientPacket, received: invoke 73 bytes
(object begin)
Property:
Property:
Property: NULL
Property:
(object begin)
Property:
Property:
(object end)
(object end)
HandleInvoke, server invoking <onstatus>
HandleInvoke, onStatus: NetStream.Publish.Start
Stream mapping:
Stream #1:0 -> #0:0 (rawvideo (native) -> h264 (libx264))
Stream #0:0 -> #0:1 (pcm_s16le (native) -> mp3 (libmp3lame))
Press [q] to stop, [?] for help
[graph 0 input from stream 1:0 @ 0x5607d087e060] w:854 h:480 pixfmt:bgr0 tb:1/30 fr:30/1 sar:0/1 sws_param:flags=2
[auto_scaler_0 @ 0x5607d087d800] w:iw h:ih flags:'bicubic' interl:0
[format @ 0x5607d087ed40] auto-inserting filter 'auto_scaler_0' between the filter 'Parsed_null_0' and the filter 'format'
[auto_scaler_0 @ 0x5607d087d800] w:854 h:480 fmt:bgr0 sar:0/1 -> w:854 h:480 fmt:yuv420p sar:0/1 flags:0x4
[swscaler @ 0x5607d0880260] Warning: data is not aligned! This can lead to a speed loss
[libx264 @ 0x5607d08684e0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
[libx264 @ 0x5607d08684e0] profile Constrained Baseline, level 3.1
[libx264 @ 0x5607d08684e0] 264 - core 148 r2748 97eaef2 - H.264/MPEG-4 AVC codec - Copyleft 2003-2016 - http://www.videolan.org/x264.html - options: cabac=0 ref=1 deblock=0:0:0 analyse=0:0 me=dia subme=0 psy=1 psy_rd=1.00:0.00 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=0 threads=2 lookahead_threads=2 sliced_threads=1 slices=2 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=0 keyint=60 keyint_min=6 scenecut=0 intra_refresh=0 rc_lookahead=0 rc=crf mbtree=0 crf=26.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 vbv_maxrate=1500 vbv_bufsize=1500 crf_max=0.0 nal_hrd=none filler=0 ip_ratio=1.40 aq=0
[graph_1_in_0_0 @ 0x5607d091c840] tb:1/48000 samplefmt:s16 samplerate:48000 chlayout:0x3
[Parsed_aresample_0 @ 0x5607d0916b40] ch:2 chl:stereo fmt:s16 r:48000Hz -> ch:2 chl:stereo fmt:s16p r:44100Hz
Output #0, flv, to 'rtmp://a.rtmp.youtube.com/live2/{KEY}':
Metadata:
encoder : Lavf58.3.100
Stream #0:0: Video: h264 (libx264), 1 reference frame ([7][0][0][0] / 0x0007), yuv420p(top coded first (swapped)), 854x480, q=-1--1, 1000 kb/s, 30 fps, 1k tbn, 30 tbc
Metadata:
encoder : Lavc58.6.103 libx264
Side data:
cpb: bitrate max/min/avg: 1500000/0/1000000 buffer size: 1500000 vbv_delay: -1
Stream #0:1: Audio: mp3 (libmp3lame) ([2][0][0][0] / 0x0002), 44100 Hz, stereo, s16p, delay 1105, 192 kb/s
Metadata:
encoder : Lavc58.6.103 libmp3lame
frame= 29 fps=0.0 q=17.0 size= 146kB time=00:00:00.94 bitrate=1267.3kbits/s speed=1.86x
frame= 44 fps= 44 q=18.0 size= 168kB time=00:00:01.46 bitrate= 942.4kbits/s speed=1.45x
frame= 60 fps= 40 q=16.0 size= 191kB time=00:00:01.96 bitrate= 794.8kbits/s speed= 1.3x
...
frame= 2740 fps= 30 q=17.0 size= 7993kB time=00:01:31.32 bitrate= 717.0kbits/s speed= 1x
frame= 2755 fps= 30 q=18.0 size= 8013kB time=00:01:31.82 bitrate= 714.9kbits/s speed= 1x
[alsa @ 0x5607d084d7e0] ALSA buffer xrun.
</onstatus></createstream></onbwdone></connect>