
Recherche avancée
Médias (1)
-
La conservation du net art au musée. Les stratégies à l’œuvre
26 mai 2011
Mis à jour : Juillet 2013
Langue : français
Type : Texte
Autres articles (42)
-
La sauvegarde automatique de canaux SPIP
1er avril 2010, parDans le cadre de la mise en place d’une plateforme ouverte, il est important pour les hébergeurs de pouvoir disposer de sauvegardes assez régulières pour parer à tout problème éventuel.
Pour réaliser cette tâche on se base sur deux plugins SPIP : Saveauto qui permet une sauvegarde régulière de la base de donnée sous la forme d’un dump mysql (utilisable dans phpmyadmin) mes_fichiers_2 qui permet de réaliser une archive au format zip des données importantes du site (les documents, les éléments (...) -
Publier sur MédiaSpip
13 juin 2013Puis-je poster des contenus à partir d’une tablette Ipad ?
Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir -
MediaSPIP 0.1 Beta version
25 avril 2011, parMediaSPIP 0.1 beta is the first version of MediaSPIP proclaimed as "usable".
The zip file provided here only contains the sources of MediaSPIP in its standalone version.
To get a working installation, you must manually install all-software dependencies on the server.
If you want to use this archive for an installation in "farm mode", you will also need to proceed to other manual (...)
Sur d’autres sites (7495)
-
Convert RAW images to BMP format
3 juin 2021, par Tina JI received a
.raw
frame format (here is a sample) which contains the raw pixel values of a frame. And I've been told I can convert it to an image (.bmp or .png) usingFFMpeg
using following command. However, when trying, it doesn't work.

dd bs=16 dumpB4EncodeHLSAfterEncodeBuf1200IP_TS/dumpedYuv/image-1140.raw | ffmpeg -f rawvideo -video_size 2160 2160 -pixel_format nv12 -i - yuv.bmp



What is the problem ? Is there any ways to avoid use of
dd
and purely do it fromFFmpeg
?

Here is the error :


dd: unrecognized operand ‘frame.raw’
Try 'dd --help' for more information.
ffmpeg version 3.4.8-0ubuntu0.2 Copyright (c) 2000-2020 the FFmpeg developers
 built with gcc 7 (Ubuntu 7.5.0-3ubuntu1~18.04)
 configuration: --prefix=/usr --extra-version=0ubuntu0.2 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-librsvg --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared
 libavutil 55. 78.100 / 55. 78.100
 libavcodec 57.107.100 / 57.107.100
 libavformat 57. 83.100 / 57. 83.100
 libavdevice 57. 10.100 / 57. 10.100
 libavfilter 6.107.100 / 6.107.100
 libavresample 3. 7. 0 / 3. 7. 0
 libswscale 4. 8.100 / 4. 8.100
 libswresample 2. 9.100 / 2. 9.100
 libpostproc 54. 7.100 / 54. 7.100
pipe:: Invalid data found when processing input



And if I use ffmpeg directly :


ffmpeg -video_size 2160x2160 -pixel_format nv12 -i frame.raw yuv.bmp



I will get this error :


ffmpeg version 3.4.8-0ubuntu0.2 Copyright (c) 2000-2020 the FFmpeg developers
 built with gcc 7 (Ubuntu 7.5.0-3ubuntu1~18.04)
 configuration: --prefix=/usr --extra-version=0ubuntu0.2 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-librsvg --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared
 libavutil 55. 78.100 / 55. 78.100
 libavcodec 57.107.100 / 57.107.100
 libavformat 57. 83.100 / 57. 83.100
 libavdevice 57. 10.100 / 57. 10.100
 libavfilter 6.107.100 / 6.107.100
 libavresample 3. 7. 0 / 3. 7. 0
 libswscale 4. 8.100 / 4. 8.100
 libswresample 2. 9.100 / 2. 9.100
 libpostproc 54. 7.100 / 54. 7.100
[image2 @ 0x5605e52bb4c0] Format image2 detected only with low score of 5, misdetection possible!
Input #0, image2, from 'frame.raw':
 Duration: 00:00:00.04, start: 0.000000, bitrate: 1244160 kb/s
 Stream #0:0: Video: rawvideo (NV12 / 0x3231564E), nv12, 2160x2160, 25 tbr, 25 tbn, 25 tbc
Stream mapping:
 Stream #0:0 -> #0:0 (rawvideo (native) -> bmp (native))
Press [q] to stop, [?] for help
[rawvideo @ 0x5605e52bea00] Invalid buffer size, packet size 6220800 < expected frame_size 6998400
Error while decoding stream #0:0: Invalid argument
Finishing stream 0:0 without any data written to it.
Output #0, image2, to 'yuv.bmp':
 Metadata:
 encoder : Lavf57.83.100
 Stream #0:0: Video: bmp, bgr24, 2160x2160, q=2-31, 200 kb/s, 25 fps, 25 tbn, 25 tbc
 Metadata:
 encoder : Lavc57.107.100 bmp
frame= 0 fps=0.0 q=0.0 Lsize=N/A time=00:00:00.00 bitrate=N/A speed= 0x
video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
Output file is empty, nothing was encoded (check -ss / -t / -frames parameters if used)
Conversion failed!



-
Combining three or more videos with ffmpeg and the xfade filter
25 février 2021, par silAs of 2020 ffmpeg has the xfade filter which can combine videos with a transition. Combining two videos is easy enough :


ffmpeg -i vid1.mp4 -i vid2.mp4 \
 -filter_complex [0][1]xfade=transition=pixelize:duration=1:offset=4,format=yuv420p" \
 out.mp4



But I don't understand how to combine three videos (so that v1 fades into v2 and v2 then fades into v3. I tried something like this :


ffmpeg -i vid1.mp4 -i vid2.mp4 -i vid3.mp4 \
 -filter_complex [0][1]xfade=transition=pixelize:duration=1:offset=4,format=yuv420p[0n1];[0n1][2]xfade=transition=pixelize:duration=1:offset=9,format=yuv420p" \
 out.mp4



but that doesn't work. My idea was that 0 and 1, or vid1 and vid2, would be combined into a [0n1] stream with a transition by xfade, and then that 0n1 stream could be combined with vid3 with another filter. As far as I can tell, this includes the first two videos but not the third. What this of course means is that I don't understand how to specify a filtergraph correctly !


How should I use xfade to combine 3 or more videos with transitions between them ?


A full example is as follows. Here I'll use three images (because then issues with combining videos at different frame rates are avoided), and smash them all to 500x500 for ease (in the final version they would be letterboxed to keep resolution and so on).


ffmpeg \
 -loop 1 -t 5 -i tests/p1.jpg \
 -loop 1 -t 5 -i tests/p2.jpg \
 -loop 1 -t 5 -i tests/p3.jpg \
 -filter_complex "[0]scale=500:500[s0];[1]scale=500:500[s1];[2]scale=500:500[s2];[s0][s1]xfade=transition=pixelize:duration=1:offset=4,format=yuv420p[s01];[s01][s2]xfade=transition=pixelize:duration=1:offset=9,format=yuv420p" out.mp4



I would expect this to create a video which was :


- 

- 4 seconds of p1.jpg
- a pixelise transition into p2.jpg lasting 1 second
- 4 seconds of p2.jpg
- a pixelise transition into p3.jpg lasting 1 second
- 4 seconds of p3.jpg












but what I actually get is


- 

- 4 seconds of p1.jpg
- a pixelise transition into p2.jpg lasting 1 second
- 4 seconds of p2.jpg








and then the video ends. p3 is not included at all.


The output is as follows :


ffmpeg version N-53546-g5eb4405fc5-static https://johnvansickle.com/ffmpeg/ Copyright (c) 2000-2020 the FFmpeg developers
 built with gcc 8 (Debian 8.3.0-6)
 configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gmp --enable-libgme --enable-gray --enable-libaom --enable-libfribidi --enable-libass --enable-libvmaf --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librubberband --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libdav1d --enable-libxvid --enable-libzvbi --enable-libzimg
 libavutil 56. 56.100 / 56. 56.100
 libavcodec 58. 97.100 / 58. 97.100
 libavformat 58. 49.100 / 58. 49.100
 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, image2, from 'tests/p1.jpg':
 Duration: 00:00:00.04, start: 0.000000, bitrate: 44845 kb/s
 Stream #0:0: Video: mjpeg (Baseline), yuvj444p(pc, bt470bg/unknown/unknown), 820x1270 [SAR 150:150 DAR 82:127], 25 fps, 25 tbr, 25 tbn, 25 tbc
Input #1, image2, from 'tests/p2.jpg':
 Duration: 00:00:00.04, start: 0.000000, bitrate: 22325 kb/s
 Stream #1:0: Video: mjpeg (Baseline), yuvj420p(pc, bt470bg/unknown/unknown), 960x600 [SAR 1:1 DAR 8:5], 25 fps, 25 tbr, 25 tbn, 25 tbc
Input #2, image2, from 'tests/p3.jpg':
 Duration: 00:00:00.04, start: 0.000000, bitrate: 15266 kb/s
 Stream #2:0: Video: mjpeg (Baseline), yuvj420p(pc, bt470bg/unknown/unknown), 728x669 [SAR 96:96 DAR 728:669], 25 fps, 25 tbr, 25 tbn, 25 tbc
File 'out.mp4' already exists. Overwrite? [y/N] y
Stream mapping:
 Stream #0:0 (mjpeg) -> scale
 Stream #1:0 (mjpeg) -> scale
 Stream #2:0 (mjpeg) -> scale
 format -> Stream #0:0 (libx264)
Press [q] to stop, [?] for help
[swscaler @ 0x8228040] deprecated pixel format used, make sure you did set range correctly
[swscaler @ 0x8258640] deprecated pixel format used, make sure you did set range correctly
[swscaler @ 0x827df40] deprecated pixel format used, make sure you did set range correctly
[swscaler @ 0x829f800] deprecated pixel format used, make sure you did set range correctly
[swscaler @ 0x82c13c0] deprecated pixel format used, make sure you did set range correctly
[swscaler @ 0x82e8340] deprecated pixel format used, make sure you did set range correctly
[libx264 @ 0x77b7600] using SAR=82/127
[libx264 @ 0x77b7600] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
[libx264 @ 0x77b7600] profile High, level 3.0, 4:2:0, 8-bit
[libx264 @ 0x77b7600] 264 - core 161 r3018 db0d417 - H.264/MPEG-4 AVC codec - Copyleft 2003-2020 - 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=25 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 'out.mp4':
 Metadata:
 encoder : Lavf58.49.100
 Stream #0:0: Video: h264 (libx264) (avc1 / 0x31637661), yuv420p, 500x500 [SAR 82:127 DAR 82:127], q=-1--1, 25 fps, 12800 tbn, 25 tbc (default)
 Metadata:
 encoder : Lavc58.97.100 libx264
 Side data:
 cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: N/A
frame= 101 fps=100 q=28.0 size= 0kB time=00:00:01.92 bitrate= 0.2kbits/s speed=[swscaler @ 0x8291d80] deprecated pixel format used, make sure you did set range correctly
 Last message repeated 2 times
[swscaler @ 0x82b3000] deprecated pixel format used, make sure you did set range correctly
 Last message repeated 2 times
[swscaler @ 0x82fc200] deprecated pixel format used, make sure you did set range correctly
 Last message repeated 2 times
frame= 153 fps=101 q=28.0 size= 0kB time=00:00:04.00 bitrate= 0.1kbits/s speed=[swscaler @ 0x82fc200] deprecated pixel format used, make sure you did set range correctly
 Last message repeated 2 times
frame= 225 fps=111 q=28.0 size= 256kB time=00:00:06.88 bitrate= 304.9kbits/s dup=0 frame= 225 fps= 95 q=-1.0 Lsize= 267kB time=00:00:08.88 bitrate= 245.9kbits/s dup=0 drop=125 speed=3.74x 
video:263kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 1.293847%
[libx264 @ 0x77b7600] frame I:2 Avg QP:21.03 size: 19928
[libx264 @ 0x77b7600] frame P:66 Avg QP:21.18 size: 2453
[libx264 @ 0x77b7600] frame B:157 Avg QP:29.72 size: 427
[libx264 @ 0x77b7600] consecutive B-frames: 5.3% 4.4% 1.3% 88.9%
[libx264 @ 0x77b7600] mb I I16..4: 29.0% 27.8% 43.2%
[libx264 @ 0x77b7600] mb P I16..4: 10.8% 3.2% 7.5% P16..4: 2.6% 0.9% 0.3% 0.0% 0.0% skip:74.8%
[libx264 @ 0x77b7600] mb B I16..4: 1.1% 0.5% 1.6% B16..8: 1.0% 0.5% 0.1% direct: 0.3% skip:94.9% L0:37.4% L1:43.5% BI:19.1%
[libx264 @ 0x77b7600] 8x8 transform intra:16.5% inter:55.3%
[libx264 @ 0x77b7600] coded y,uvDC,uvAC intra: 31.4% 71.7% 31.8% inter: 1.1% 1.4% 0.1%
[libx264 @ 0x77b7600] i16 v,h,dc,p: 45% 46% 9% 1%
[libx264 @ 0x77b7600] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 25% 30% 27% 6% 1% 1% 2% 1% 7%
[libx264 @ 0x77b7600] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 56% 31% 9% 1% 1% 1% 1% 1% 1%
[libx264 @ 0x77b7600] i8c dc,h,v,p: 46% 27% 23% 4%
[libx264 @ 0x77b7600] Weighted P-Frames: Y:10.6% UV:7.6%
[libx264 @ 0x77b7600] ref P L0: 61.9% 17.1% 13.9% 6.8% 0.3%
[libx264 @ 0x77b7600] ref B L0: 76.3% 22.8% 0.9%
[libx264 @ 0x77b7600] ref B L1: 97.6% 2.4%
[libx264 @ 0x77b7600] kb/s:238.88



-
How to fix grainy recoding with ffmpeg mp4 x264 ?
21 mars 2020, par teenserieI recorded the audio and video stream from a streaming with ffmpeg. when I go to re-encode the file using libx264, the video in the movements looks bad and grainy as in the image.
Where did I go wrong ?this is the code I used
ffmpeg -i input.mp4 -c:v libx264 -c:a aac output.mp4
and these are mediainfo of original file
Metadata:
major_brand : isom
minor_version : 1
compatible_brands: isom
creation_time : 2020-03-19T22:43:32.000000Z
Duration: 00:39:51.99, start: 0.000000, bitrate: 1300 kb/s
Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv, bt709), 1280x1080 [SAR 3:2 DAR 16:9], Closed Captions, 1268 kb/s, 59.94 fps, 59.94 tbr, 90k tbn, 59.94 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #0:1(spa): Audio: aac (HE-AACv2) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 22 kb/s (default)
Metadata:
handler_name : SoundHandlermediainfo of the file recoded
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.29.100
Duration: 00:39:51.99, start: 0.000000, bitrate: 7924 kb/s
Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], Closed Captions, 7892 kb/s, 59.94 fps, 59.94 tbr, 60k tbn, 119.88 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #0:1(spa): Audio: aac (HE-AACv2) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 22 kb/s (default)
Metadata:
handler_name : SoundHandlerHow can I recode the file without loss of quality ? (sorry for my poor english)