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Collections - Formulaire de création rapide
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Mis à jour : Février 2013
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Ne pas afficher certaines informations : page d’accueil
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Richard Stallman et la révolution du logiciel libre - Une biographie autorisée (version epub)
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Autres articles (80)
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Amélioration de la version de base
13 septembre 2013Jolie sélection multiple
Le plugin Chosen permet d’améliorer l’ergonomie des champs de sélection multiple. Voir les deux images suivantes pour comparer.
Il suffit pour cela d’activer le plugin Chosen (Configuration générale du site > Gestion des plugins), puis de configurer le plugin (Les squelettes > Chosen) en activant l’utilisation de Chosen dans le site public et en spécifiant les éléments de formulaires à améliorer, par exemple select[multiple] pour les listes à sélection multiple (...) -
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 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 (...)
Sur d’autres sites (9905)
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FFmpeg fontcolor_expr to dynamically change fontcolor over time
26 juin 2017, par MatthewI’m using Fluent-FFmpeg with Node.JS to create videos with text overlaid on them and I’m wanting to change the color of the text as the video progresses.
My filters follow this pattern :
drawtext=enable='between(t,18.93,20.28)':fontfile=fonts/cousine-bold.ttf:fontsize=144:fontcolor_expr=%{expr\\\: if(between(t\\, 0\\, 20)\\, 888888\\, 111111)}:x=82:y=288:text='PROGRAMMING'
And it prints out this stuff :
ffmpeg version 3.3.2 Copyright (c) 2000-2017 the FFmpeg developers
built with Apple LLVM version 8.1.0 (clang-802.0.42)
configuration: --prefix=/usr/local/Cellar/ffmpeg/3.3.2 --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-libfreetype --enable-libmp3lame --enable-libx264 --enable-libxvid --enable-opencl --disable-lzma --enable-vda
libavutil 55. 58.100 / 55. 58.100
libavcodec 57. 89.100 / 57. 89.100
libavformat 57. 71.100 / 57. 71.100
libavdevice 57. 6.100 / 57. 6.100
libavfilter 6. 82.100 / 6. 82.100
libavresample 3. 5. 0 / 3. 5. 0
libswscale 4. 6.100 / 4. 6.100
libswresample 2. 7.100 / 2. 7.100
libpostproc 54. 5.100 / 54. 5.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'uploads/0c719e39820366bc62c8fd66a6327828':
Metadata:
major_brand : qt
minor_version : 0
compatible_brands: qt
creation_time : 2017-06-23T00:19:46.000000Z
com.apple.quicktime.make: Apple
com.apple.quicktime.model: MacBookPro9,2
com.apple.quicktime.software: Mac OS X 10.12.5 (16F73)
com.apple.quicktime.creationdate: 2017-06-22T17:18:42-0700
Duration: 00:00:22.00, start: 0.000000, bitrate: 3408 kb/s
Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, bt709, progressive), 1280x720 [SAR 1:1 DAR 16:9], 3091 kb/s, 15 fps, 15 tbr, 30k tbn, 50 tbc (default)
Metadata:
creation_time : 2017-06-23T00:19:46.000000Z
handler_name : Core Media Data Handler
encoder : H.264
Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 316 kb/s (default)
Metadata:
creation_time : 2017-06-23T00:19:46.000000Z
handler_name : Core Media Data Handler
Stream mapping:
Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
Stream #0:1 -> #0:1 (aac (native) -> aac (native))
Press [q] to stop, [?] for help
[libx264 @ 0x7ff72e810a00] using SAR=1/1
[libx264 @ 0x7ff72e810a00] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
[libx264 @ 0x7ff72e810a00] profile High, level 3.1
[libx264 @ 0x7ff72e810a00] 264 - core 148 r2748 97eaef2 - H.264/MPEG-4 AVC codec - Copyleft 2003-2016 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=6 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=15 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to './outputFile.mp4':
Metadata:
major_brand : qt
minor_version : 0
compatible_brands: qt
com.apple.quicktime.creationdate: 2017-06-22T17:18:42-0700
com.apple.quicktime.make: Apple
com.apple.quicktime.model: MacBookPro9,2
com.apple.quicktime.software: Mac OS X 10.12.5 (16F73)
encoder : Lavf57.71.100
Stream #0:0(und): Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], q=-1--1, 15 fps, 15360 tbn, 15 tbc (default)
Metadata:
creation_time : 2017-06-23T00:19:46.000000Z
handler_name : Core Media Data Handler
encoder : Lavc57.89.100 libx264
Side data:
cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
Stream #0:1(und): Audio: aac (LC) ([64][0][0][0] / 0x0040), 44100 Hz, stereo, fltp, 128 kb/s (default)
Metadata:
creation_time : 2017-06-23T00:19:46.000000Z
handler_name : Core Media Data Handler
encoder : Lavc57.89.100 aac
frame= 52 fps=0.0 q=27.0 size= 37kB time=00:00:04.66 bitrate= 65.7kbits/s speed=8.74x
frame= 72 fps= 70 q=27.0 size= 187kB time=00:00:06.03 bitrate= 253.4kbits/s speed=5.83x
frame= 95 fps= 61 q=27.0 size= 358kB time=00:00:07.52 bitrate= 390.4kbits/s speed=4.82x
frame= 117 fps= 57 q=27.0 size= 569kB time=00:00:08.98 bitrate= 518.9kbits/s speed=4.35x
frame= 137 fps= 53 q=27.0 size= 732kB time=00:00:10.32 bitrate= 580.2kbits/s speed=4.03x
frame= 159 fps= 52 q=27.0 size= 942kB time=00:00:11.79 bitrate= 654.7kbits/s speed=3.84x
frame= 180 fps= 50 q=27.0 size= 1110kB time=00:00:13.18 bitrate= 689.5kbits/s speed=3.67x
frame= 204 fps= 50 q=27.0 size= 1331kB time=00:00:14.78 bitrate= 737.2kbits/s speed= 3.6x
frame= 223 fps= 48 q=27.0 size= 1486kB time=00:00:16.06 bitrate= 757.9kbits/s speed=3.49x
frame= 248 fps= 48 q=27.0 size= 1708kB time=00:00:17.71 bitrate= 789.7kbits/s speed=3.46x
frame= 266 fps= 47 q=27.0 size= 1859kB time=00:00:18.92 bitrate= 805.0kbits/s speed=3.35x
frame= 285 fps= 46 q=27.0 size= 2013kB time=00:00:20.19 bitrate= 816.4kbits/s speed=3.28x
[drawtext @ 0x7ff72d84bc00] Cannot find color '888888.000000'
Last message repeated 9 times
frame= 308 fps= 46 q=27.0 size= 2224kB time=00:00:21.75 bitrate= 837.5kbits/s speed=3.27x
frame= 330 fps= 46 q=27.0 size= 2401kB time=00:00:21.96 bitrate= 895.5kbits/s speed=3.06x
frame= 330 fps= 41 q=-1.0 Lsize= 2834kB time=00:00:22.00 bitrate=1055.0kbits/s speed=2.73x
video:2484kB audio:338kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.441003%
[libx264 @ 0x7ff72e810a00] frame I:22 Avg QP:13.64 size: 47604
[libx264 @ 0x7ff72e810a00] frame P:154 Avg QP:16.76 size: 8574
[libx264 @ 0x7ff72e810a00] frame B:154 Avg QP:19.42 size: 1138
[libx264 @ 0x7ff72e810a00] consecutive B-frames: 6.7% 93.3% 0.0% 0.0%
[libx264 @ 0x7ff72e810a00] mb I I16..4: 85.1% 13.3% 1.6%
[libx264 @ 0x7ff72e810a00] mb P I16..4: 5.5% 3.1% 0.0% P16..4: 41.5% 4.0% 5.5% 0.0% 0.0% skip:40.4%
[libx264 @ 0x7ff72e810a00] mb B I16..4: 0.0% 0.0% 0.0% B16..8: 14.7% 0.1% 0.0% direct: 4.7% skip:80.4% L0:28.0% L1:71.4% BI: 0.7%
[libx264 @ 0x7ff72e810a00] 8x8 transform intra:21.7% inter:84.8%
[libx264 @ 0x7ff72e810a00] coded y,uvDC,uvAC intra: 60.5% 98.6% 92.9% inter: 6.0% 24.3% 3.1%
[libx264 @ 0x7ff72e810a00] i16 v,h,dc,p: 35% 19% 43% 3%
[libx264 @ 0x7ff72e810a00] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 10% 7% 80% 1% 1% 1% 1% 0% 0%
[libx264 @ 0x7ff72e810a00] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 33% 20% 45% 0% 0% 0% 0% 0% 0%
[libx264 @ 0x7ff72e810a00] i8c dc,h,v,p: 77% 9% 10% 4%
[libx264 @ 0x7ff72e810a00] Weighted P-Frames: Y:0.0% UV:0.0%
[libx264 @ 0x7ff72e810a00] ref P L0: 75.3% 0.3% 17.1% 7.3%
[libx264 @ 0x7ff72e810a00] ref B L0: 80.0% 20.0%
[libx264 @ 0x7ff72e810a00] kb/s:924.66
[aac @ 0x7ff72e812200] Qavg: 2159.960In particular this annoying bit :
[drawtext @ 0x7ff72d84bc00] Cannot find color '888888.000000'
However, it would be really nice to do something like this :
fontcolor_expr=%{expr\\\\: if(between(t\\, 0\\, 20)\\, pink\\, white)}
Which prints out this error :
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Undefined constant or missing '(' in 'pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Missing ')' or too many args in 'if(between(t,0,20),pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] Expression 'if(between(t, 0, 20), pink, white)' for the expr text expansion function is not valid
frame= 287 fps= 46 q=27.0 size= 2023kB time=00:00:20.31 bitrate= 815.9kbits/s speed=3.27x
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Undefined constant or missing '(' in 'pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Missing ')' or too many args in 'if(between(t,0,20),pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] Expression 'if(between(t, 0, 20), pink, white)' for the expr text expansion function is not valid
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Undefined constant or missing '(' in 'pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Missing ')' or too many args in 'if(between(t,0,20),pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] Expression 'if(between(t, 0, 20), pink, white)' for the expr text expansion function is not valid
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Undefined constant or missing '(' in 'pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Missing ')' or too many args in 'if(between(t,0,20),pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] Expression 'if(between(t, 0, 20), pink, white)' for the expr text expansion function is not valid
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Undefined constant or missing '(' in 'pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Missing ')' or too many args in 'if(between(t,0,20),pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] Expression 'if(between(t, 0, 20), pink, white)' for the expr text expansion function is not valid
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Undefined constant or missing '(' in 'pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Missing ')' or too many args in 'if(between(t,0,20),pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] Expression 'if(between(t, 0, 20), pink, white)' for the expr text expansion function is not valid
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Undefined constant or missing '(' in 'pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Missing ')' or too many args in 'if(between(t,0,20),pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] Expression 'if(between(t, 0, 20), pink, white)' for the expr text expansion function is not valid
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Undefined constant or missing '(' in 'pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Missing ')' or too many args in 'if(between(t,0,20),pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] Expression 'if(between(t, 0, 20), pink, white)' for the expr text expansion function is not valid
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Undefined constant or missing '(' in 'pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Missing ')' or too many args in 'if(between(t,0,20),pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] Expression 'if(between(t, 0, 20), pink, white)' for the expr text expansion function is not valid
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Undefined constant or missing '(' in 'pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] [Eval @ 0x7fff5f7760c0] Missing ')' or too many args in 'if(between(t,0,20),pink,white)'
[Parsed_drawtext_0 @ 0x7ff3cf523300] Expression 'if(between(t, 0, 20), pink, white)' for the expr text expansion function is not validThere aren’t a lot of examples of fontcolor_expr, so I wanted to see if anyone had experience with this. Any tips on changing fonrcolors dynamically without creating multiple filters ?
Please note that
fontcolor_expr=white
andfontcolor_expr=888888
are valid and create videos with a fixed font color. -
Dreamcast SD Adapter and DreamShell
31 décembre 2014, par Multimedia Mike — Sega DreamcastNope ! I’m never going to let go of the Sega Dreamcast hacking. When I was playing around with Dreamcast hacking early last year, I became aware that there is such a thing as an SD card adapter for the DC that plugs into the port normally reserved for the odd DC link cable. Of course I wanted to see what I could do with it.
The primary software that leverages the DC SD adapter is called DreamShell. Working with this adapter and the software requires some skill and guesswork. Searching for these topics tends to turn up results from various forums where people are trying to cargo-cult their way to solutions. I have a strange feeling that this post might become the unofficial English-language documentation on the matter.
Use Cases
What can you do with this thing ? Undoubtedly, the primary use is for backing up (ripping) the contents of GD-ROMs (the custom optical format used for the DC) and playing those backed up (ripped) copies. Presumably, users of this device leverage the latter use case more than the former, i.e., download ripped games, load them on the SD card, and launch them using DreamShell.However, there are other uses such as multimedia playback, system exploration, BIOS reprogramming, high-level programming, and probably a few other things I haven’t figured out yet.
Delivery
I put in an order via the dc-sd.com website and in about 2 short months, the item arrived from China. This marked my third lifetime delivery from China and curiously, all 3 of the shipments have pertained to the Sega Dreamcast.
I thought it was very interesting that this adapter came in such complete packaging. The text is all in Chinese, though the back states “Windows 98 / ME / 2000 / XP, Mac OS 9.1, LINUX2.4”. That’s what tipped me off that they must have just cannibalized some old USB SD card readers and packaging in order to create these. Closer inspection of the internals through the translucent pink case confirms this.
Usage
According to its change log, DreamShell has been around for a long time with version 1.0.0 released in February of 2004. The current version is 4.0.0 RC3. There are several downloads available :- DreamShell 4.0 RC 3 CDI Image
- DreamShell 4.0 RC 3 + Boot Loader
- DreamShell 4.0 RC 3 + Core CDI image
Option #2 worked for me. It contains a CDI disc image and the DreamShell files in a directory named DS/.
Burn the CDI to a CD-R in the normal way you would burn a bootable Dreamcast disc from a CDI image. This is open-ended and left as an exercise to the reader, since there are many procedures depending on platform. On Linux, I used a small script I found once called burncdi-dc.sh.
Then, copy the contents of the DS/ folder to an SD card. As for filesystem, FAT16 and FAT32 are both known to work. The files in DS/ should land in the root of the SD card ; the folder DS/ should not be in the root.
Plug the SD card into the DC SD adapter and plug the adapter in the link cable port on the back of the Dreamcast. Then, boot the disc. If it works, you will see this minor corruption of the usual Sega licensing screen :
Then, there will be a brief white-on-black text screen that explains the booting process :
Then, there will be the main DreamShell logo :
Finally, you will land on the DreamShell main desktop :
Skepticism
At first, I was supremely skeptical of the idea that this SD adapter could perform speedily enough to play games reasonably. This was predicated on the observation that my DC coder’s cable that I used to use for homebrew development could not transfer faster than 115200 bits/second, amounting to about 11 kbytes/sec. I assumed that this was a fundamental limitation of the link port.In fact, I ripped a few of my Dreamcast discs over a decade ago and still have those rips lying around. So I copied the ISO image of Resident Evil : Code Veronica — the game I personally played most on the DC — to the SD card (anywhere works) and used the “ISO loader” icon seen on the desktop above to launch the game.
It works :
The opening FMV plays at full speed. Everything loads as fast as I remember. I was quite surprised.
Digression : My assumptions about serial speeds have often been mistaken. 10 years ago, I heard stories about how we would soon be able to watch streaming video on our cell phones. I scoffed because I thought the 56K limitation of dialup modems was some sort of fundamental speed-of-light type of limitation for telephony bandwidth, wired or wireless.
The desktop menu also includes a ‘speedtest’ tool that profiles the write and read performance of your preferred storage medium. For my fastest SD card (a PNY 2 GB card) :
This is probably more representative of the true adapter bandwidth as reading and writing is a good deal faster through more modern interfaces on PC and Mac with this same card.
Look at the other options on the speedtest console. Hard drive ? Apparently, it’s possible, but it requires a good deal more hardware hacking than just purchasing this SD adapter.
Ripping
As you can see from the Resident Evil screenshot, playing games works quite nicely. How about ripping ? I’m pleased to say that DreamShell has a beautiful ripping interface :
Enter a name for the disc (or read the disc label), select the storage medium, and let it, well, rip. It indicates which track it’s working on and the Sega logo acts as a progress bar, shading blue as the track rip progresses.
I’m finally, efficiently, archiving that collection of Sega Dreamcast demo discs ; I’m hoping they’ll eventually find a home at the Internet Archive. How is overall ripping performance ? Usually about 38-40 minutes to rip a full 900-1000 MB. That certainly beats the 27-28 hours that were required when I performed the ripping at 11 kbytes/sec via the DC coders cable.
All is well until I get a sector reading error :
That’s when it can come in handy to have 3 DC consoles (see ?! not crazy !).
Other Uses
There’s a file explorer. You can browse the filesystem of the SD card, visual memory unit, or the CD portion of the GD-ROM (would be more useful if it accessed the GD area). There are FFmpeg files included. So I threw a random Cinepak file and random MPEG-1 file at it to see what happens. MPEG-1 didn’t do anything, but this Cinepak file from some Sierra game played handily :
If you must enter strings, it helps to have a Dreamcast keyboard (which I do). Failing that, here’s a glimpse of the onscreen keyboard that DreamShell equips :
Learning to use it is a game in itself.
There is an option of installing DreamShell in the BIOS. I did not attempt this. I don’t know if it’s possible (not like there’s a lot of documentation)– perhaps a custom BIOS modchip is needed. But here’s what the screen looks like :
There is also a plain console to interact with (better have a physical keyboard). There are numerous file manipulation commands and custom system interaction commands. I see one interesting command called ‘addr’ that looks useful for dumping memory regions to a file.
A Lua language interpreter is also built in. I would love to play with this if I could ascertain whether DreamShell provided Dreamcast-specific APIs.
Tips And Troubleshooting
I have 3 Dreamcast consoles, affectionately named Terran, Protoss, and Zerg after the StarCraft II stickers with which they are adorned. Some seem to work better than others. Protoss seemed to be able to boot the DreamShell disc more reliably than the others. However, I was alarmed when it couldn’t boot one morning when it was churning the previous day.I think the problem is that it was just cold. That seemed to be the issue. I put in a normal GD-ROM and let it warm up on that disc for awhile and then DreamShell booted fine. So that’s my piece of cargo-culting troubleshooting advice.
-
FFMPEG concat demuxer - how to make file formats compatible ?
10 avril 2015, par user206481I need to automate mp4 concatenation server-side and I’m using FFMPEG. I will get uploads of mp4 files and I want to attach a Title.mp4 and End.mp4 to each one. I am also overlaying a soundtrack (the input videos do not have sound) There is a potential high server load so I’d like to do it as efficiently as possible using ffmpeg’s concat demuxer to avoid re-encoding the video.
After receiving samples of each file, I am not successful and I believe it is due to mismatched file formats. My result has good Title.mp4 and audio, then when the sample uploaded mp4 is supposed to play there is garbled green/pink/red pixels on the top half of the video, then the End.mp4 plays fine. Here is my ffmpeg command and output :
$ ffmpeg -f concat -i <(printf "file '%s'\n" Title.mp4 Sample.mp4 End.mp4) -i SoundTrack.wav -c:v copy -strict -2 -y Out.mp4
ffmpeg version 2.6.1 Copyright (c) 2000-2015 the FFmpeg developers
built with gcc 4.1.2 (GCC) 20080704 (Red Hat 4.1.2-55)
configuration: --prefix=/home/dpmsmobi/ffmpeg_build --extra-cflags=-I/home/dpmsmobi/ffmpeg_build/include --extra-ldflags=-L/home/dpmsmobi/ffmpeg_build/lib --bindir=/home/dpmsmobi/bin --enable-gpl --enable-nonfree --enable-libmp3lame --enable-libvorbis --enable-libvpx --enable-libx264
libavutil 54. 20.100 / 54. 20.100
libavcodec 56. 26.100 / 56. 26.100
libavformat 56. 25.101 / 56. 25.101
libavdevice 56. 4.100 / 56. 4.100
libavfilter 5. 11.102 / 5. 11.102
libswscale 3. 1.101 / 3. 1.101
libswresample 1. 1.100 / 1. 1.100
libpostproc 53. 3.100 / 53. 3.100
Input #0, concat, from '/dev/fd/63':
Duration: N/A, start: 0.000000, bitrate: 1810 kb/s
Stream #0:0: Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv), 768x512 [SAR 1:1 DAR 3:2], 1810 kb/s, 30 fps, 30 tbr, 30k tbn, 60 tbc
Guessed Channel Layout for Input Stream #1.0 : stereo
Input #1, wav, from 'SoundTrack.wav':
Metadata:
encoded_by : Adobe Premiere Pro CC 2014 (Maci
encoder : Adobe Premiere Pro CC 2014 (Macintosh)
date : 2015-04-07
creation_time : 11:12:10
time_reference : 0
Duration: 00:00:15.06, bitrate: 1551 kb/s
Stream #1:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 48000 Hz, 2 channels, s16, 1536 kb/s
Output #0, mp4, to 'Out.mp4':
Metadata:
encoder : Lavf56.25.101
Stream #0:0: Video: h264 ([33][0][0][0] / 0x0021), yuv420p, 768x512 [SAR 1:1 DAR 3:2], q=2-31, 1810 kb/s, 30 fps, 30 tbr, 30k tbn, 30k tbc
Stream #0:1: Audio: aac ([64][0][0][0] / 0x0040), 48000 Hz, stereo, fltp, 128 kb/s
Metadata:
encoder : Lavc56.26.100 aac
Stream mapping:
Stream #0:0 -> #0:0 (copy)
Stream #1:0 -> #0:1 (pcm_s16le (native) -> aac (native))
Press [q] to stop, [?] for help
[concat @ 0x1dedc20] Thread message queue blocking; consider raising the thread_queue_size option (current value: 8)
[concat @ 0x1dedc20] DTS 69750 < 91000 out of order
[mp4 @ 0x1f75060] Non-monotonous DTS in output stream 0:0; previous: 91000, current: 69750; changing to 91001. This may result in incorrect timestamps in the output file.
<----- many more Non-monotonous DTS messages omitted here ---->
frame= 427 fps=0.0 q=-1.0 Lsize= 4123kB time=00:00:15.06 bitrate=2242.5kbits/s
video:3873kB audio:236kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.344173%I can successfully concatenate the Title.mp4 to the End.mp4, and I can successfully concatenate two Sample.mp4 files, so I know I’ve got the ffmpeg command right. I can also successfully concat the files using the following ffmpeg command with filter_complex instead of concat demuxer (this takes considerably longer due to re-encoding) :
ffmpeg -i Title.mp4 -i Sample.mp4 -i End.mp4 -i SoundTrack.wav -filter_complex '[0:0] [1:0] [2:0] concat=n=3:v=1 [v]' -map '[v]' -map 3:0 -crf 20 -strict -2 -y Out2.mp4
Here is the MediaInfo output for each type of mp4 file :
$ mediainfo Title.mp4
General
Complete name : Title.mp4
Format : MPEG-4
Format profile : Base Media / Version 2
Codec ID : mp42
File size : 693 KiB
Duration : 3s 100ms
Overall bit rate mode : Variable
Overall bit rate : 1 831 Kbps
Encoded date : UTC 2015-04-07 19:15:03
Tagged date : UTC 2015-04-07 19:15:03
©TIM : 00:00:00:00
©TSC : 30
©TSZ : 1
Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : Main@L3.1
Format settings, CABAC : Yes
Format settings, ReFrames : 3 frames
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 3s 100ms
Bit rate mode : Variable
Bit rate : 1 811 Kbps
Maximum bit rate : 3 000 Kbps
Width : 768 pixels
Height : 512 pixels
Display aspect ratio : 3:2
Frame rate mode : Constant
Frame rate : 30.000 fps
Standard : NTSC
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.154
Stream size : 685 KiB (99%)
Language : English
Encoded date : UTC 2015-04-07 19:15:03
Tagged date : UTC 2015-04-07 19:15:03
Color range : Limited
$ mediainfo Sample.mp4
General
Complete name : Sample.mp4
Format : MPEG-4
Format profile : Base Media
Codec ID : isom
File size : 2.93 MiB
Duration : 7s 9ms
Overall bit rate : 3 505 Kbps
Encoded date : UTC 1970-01-01 00:00:00
Tagged date : UTC 1970-01-01 00:00:00
Writing application : Lavf52.64.2
Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : Baseline@L3.1
Format settings, CABAC : No
Format settings, ReFrames : 1 frame
Format settings, GOP : M=1, N=30
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 7s 9ms
Bit rate : 3 500 Kbps
Width : 768 pixels
Height : 512 pixels
Display aspect ratio : 3:2
Frame rate mode : Variable
Frame rate : 30.250 fps
Minimum frame rate : 23.462 fps
Maximum frame rate : 296.053 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.294
Stream size : 2.92 MiB (100%)
Language : English
Encoded date : UTC 1970-01-01 00:00:00
Tagged date : UTC 1970-01-01 00:00:00I’m pretty sure it’s the mp42 vs isom Codec ID’s, and potentially the constant vs variable frame rates. I can’t change the input mp4’s but I know their format will stay the same. How can I reformat the Title and End mp4’s to match the input mp4 files so I can use ffmpeg concat demux ?