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Autres articles (111)
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Script d’installation automatique de MediaSPIP
25 avril 2011, parAfin de palier aux difficultés d’installation dues principalement aux dépendances logicielles coté serveur, un script d’installation "tout en un" en bash a été créé afin de faciliter cette étape sur un serveur doté d’une distribution Linux compatible.
Vous devez bénéficier d’un accès SSH à votre serveur et d’un compte "root" afin de l’utiliser, ce qui permettra d’installer les dépendances. Contactez votre hébergeur si vous ne disposez pas de cela.
La documentation de l’utilisation du script d’installation (...) -
Ajouter des informations spécifiques aux utilisateurs et autres modifications de comportement liées aux auteurs
12 avril 2011, parLa manière la plus simple d’ajouter des informations aux auteurs est d’installer le plugin Inscription3. Il permet également de modifier certains comportements liés aux utilisateurs (référez-vous à sa documentation pour plus d’informations).
Il est également possible d’ajouter des champs aux auteurs en installant les plugins champs extras 2 et Interface pour champs extras. -
Que fait exactement ce script ?
18 janvier 2011, parCe script est écrit en bash. Il est donc facilement utilisable sur n’importe quel serveur.
Il n’est compatible qu’avec une liste de distributions précises (voir Liste des distributions compatibles).
Installation de dépendances de MediaSPIP
Son rôle principal est d’installer l’ensemble des dépendances logicielles nécessaires coté serveur à savoir :
Les outils de base pour pouvoir installer le reste des dépendances Les outils de développements : build-essential (via APT depuis les dépôts officiels) ; (...)
Sur d’autres sites (8556)
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Bewildering issue - FFmpeg segment filter desyncs video
14 mai 2018, par r_jeiI need to segment a large (72GB) Prores video file and merge the segments to get a file identical to the original.
./ffmpeg -i video.mov -codec copy -f segment -segment_time 300 -segment_list list.ffcat -reset_timestamps 1 -v error chunk_%d.mov
Unfortunately the segments that come from running this command get out of sync after a few seconds of playback with Quicktime Player. Interestingly, seeking, rewinding or fast forwarding appears to resync the video correctly for at least a few seconds.
The following warning appears whenever a new segment is written :
[segment @ 0x7f87ae001200] Opening 'chunk_0.mov' for writing
[mov @ 0x7f87ad807200] Valid timecode frame rate must be specified. Minimum value is 1Yet, setting the framerate with
-r 24
doesn’t help.Some potentially relevant metadata :
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'A004_04121423_C001.mov':
Duration: 00:13:31.25, start: 0.000000, bitrate: 710117 kb/s
Stream #0:0(eng): Video: prores (apch / 0x68637061), yuv422p10le(bt709, progressive), 3840x2160, 707415 kb/s, SAR 1:1 DAR 16:9, 24 fps, 24 tbr, 24 tbn, 24 tbc (default)
Metadata:
creation_time : 2018-04-12T20:23:16.000000Z
handler_name : ?Apple Alias Data Handler
timecode : 14:23:16:02
Stream #0:1(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, stereo, s32 (24 bit), 2304 kb/s (default)
Metadata:
creation_time : 2018-04-12T20:23:16.000000Z
handler_name : ?Apple Alias Data Handler
timecode : 14:23:16:02
Stream #0:2(eng): Data: none (tmcd / 0x64636D74) (default)
Metadata:
creation_time : 2018-04-12T20:23:16.000000Z
handler_name : ?Apple Alias Data Handler
timecode : 14:23:16:02
Output #0, segment, to 'chunk_%d.mov':
Stream #0:0(eng): Video: prores (apch / 0x68637061), yuv422p10le(bt709, progressive), 3840x2160 [SAR 1:1 DAR 16:9], q=2-31, 707415 kb/s, 24 fps, 24 tbr, 12288 tbn, 24 tbc (default)
Metadata:
creation_time : 2018-04-12T20:23:16.000000Z
handler_name : ?Apple Alias Data Handler
timecode : 14:23:16:02
Stream #0:1(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, stereo, s32 (24 bit), 2304 kb/s (default)
Metadata:
creation_time : 2018-04-12T20:23:16.000000Z
handler_name : ?Apple Alias Data Handler
timecode : 14:23:16:02
Stream mapping:
Stream #0:0 -> #0:0 (copy)
Stream #0:1 -> #0:1 (copy)I’m on OS X.
Thanks so much for your time and help on this issue ! I certainly hope I’m not missing something obvious :)
UPDATE (May 10) : Comparing the original video file with the segments, I’ve found some interesting differences. Adobe Premiere reports that the original video has the following properties :
QuickTime Details:
Movie contains 1 video track(s), 1 audio track(s), 0 closed caption track(s), **and 1 timecode track(s).**
Video:
There are 19470 frames with a **duration of 1/24th.**
Video track 1:
Duration is **0:13:31:06**
Video data block #1:
Frame Size = 3840 x 2160
Compressor =
**Quality = Most (-2623.00)
Temporal = Most (1.00)**
Timecode data block #1:
Start Time = 14:23:16:02
Reel name =On the other hand, when examining the video resulting from stitching together the segments, we find the following :
QuickTime Details:
Movie contains 1 video track(s), 1 audio track(s), 0 closed caption track(s), **and 0 timecode track(s).**
Video:
There are 19470 frames with a **duration of 41/1000ths.**
Video track 1:
Duration is **0:01:06:00**
Video data block #1:
Frame Size = 3840 x 2160
Compressor =
**Quality = Normal (3.00)
Temporal = Normal (3.00)** -
libavcodec.a(vc1dsp_mmx.o) : relocation R_X86_64_PC32 against symbol `ff_pw_9'
15 juillet 2021, par Guru GovindanI am building an shared object file in ubuntu(vagrant) that uses ffmpeg libraries(libavcodec.a, libavformat.a, libavutil.a). I first used the standard configure options to build ffmpeg and libraries from trac.ffmpeg. But there was some issues with dynamic linking and I modified the configure options a little bit to add
--enable-shared
and-fPIC
options.


However when I build my application I get 
/usr/bin/ld: /root/ffmpeg_build/lib/libavcodec.a(vc1dsp_mmx.o): 
relocation R_X86_64_PC32 against symbol `ff_pw_9' can not be used when
 making a shared object; recompile with -fPIC
/usr/bin/ld: final link failed: Bad value
collect2: error: ld returned 1 exit status




I used the following options in my configure to build ffmpeg



PATH="$HOME/bin:$PATH" PKG_CONFIG_PATH="$HOME/ffmpeg_build/lib/pkgconfig:$PKG_CONFIG_PATH" ./configure \
 --prefix="$HOME/ffmpeg_build" \
 --pkg-config-flags="--static" \
 --extra-cflags="-I$HOME/ffmpeg_build/include -fPIC" \
 --extra-ldflags="-L$HOME/ffmpeg_build/lib -Wl,-Bsymbolic" \
 --extra-libs="-lpthread -lm" \
 --bindir="$HOME/bin" \
 --enable-gpl \
 --enable-libass \
 --enable-libfdk-aac \
 --enable-libfreetype \
 --enable-libmp3lame \
 --enable-libopus \
 --enable-libvorbis \
 --enable-libvpx \
 --enable-libx264 \
 --enable-libx265 \
 --enable-nonfree \
 --enable-pic \
 --enable-shared




The build works fine on my MAC.



The following is my cmake file to build my application



cmake_minimum_required(VERSION 3.5)
project(extractor C)

set(CMAKE_C_STANDARD 99)

set(EXECUTABLE_NAME "extractor")

set(CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/CMakeModules)

set(EXTRACTOR_VERSION "${CPACK_PACKAGE_VERSION_MAJOR}.${CPACK_PACKAGE_VERSION_MINOR}.${CPACK_PACKAGE_VERSION_PATCH}")
set(target_dir "bin")

# set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -g -std=99")
set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -g")
# set(CMAKE_SHARED_LINKER_FLAGS "-Wl,-Bsymbolic")


add_library(${EXECUTABLE_NAME} SHARED src/frame_extractor.c)

include_directories(".")
find_package(FFmpeg REQUIRED)

if (FFMPEG_FOUND)
 message("Found FFMPEG/LibAV libraries ${FFMPEG_LIBRARIES}")
 message("include dirs ${FFMPEG_INCLUDE_DIR}")
 include_directories(${FFMPEG_INCLUDE_DIR})
 target_link_libraries(${EXECUTABLE_NAME} ${FFMPEG_LIBRARIES})
else (FFMPEG_FOUND)
 message("cant find libavcodec, libavformat or libavutil. add them manually!!")
endif (FFMPEG_FOUND)

target_link_libraries(${EXECUTABLE_NAME} ${FFMPEG_LIBRARIES})
# target_link_libraries (${EXECUTABLE_NAME} "-lm")
# target_link_libraries (${EXECUTABLE_NAME} "-lavcodec")

if(APPLE)
 #target_link_libraries(${EXECUTABLE_NAME} "-framework CoreServices")
 #target_link_libraries(${EXECUTABLE_NAME} "-framework CoreFoundation")
 #target_link_libraries(${EXECUTABLE_NAME} "-framework AudioToolbox")
 #target_link_libraries(${EXECUTABLE_NAME} "-framework VideoToolbox")
 #target_link_libraries(${EXECUTABLE_NAME} "-framework CoreAudio")
 #target_link_libraries(${EXECUTABLE_NAME} "-framework CoreMedia")
 #target_link_libraries(${EXECUTABLE_NAME} "-framework CoreVideo")
 #target_link_libraries(${EXECUTABLE_NAME} "-framework AVFoundation")
 #target_link_libraries(${EXECUTABLE_NAME} "-framework Security")
 #target_link_libraries(${EXECUTABLE_NAME} /usr/lib/libbz2.1.0.dylib)
 #target_link_libraries(${EXECUTABLE_NAME} /usr/lib/libz.1.dylib)
 #target_link_libraries(${EXECUTABLE_NAME} /usr/lib/libiconv.dylib)
 #target_link_libraries(${EXECUTABLE_NAME} /usr/lib/liblzma.dylib)
 #target_link_libraries(${EXECUTABLE_NAME} /usr/local/lib/libswresample.a)
 #target_link_libraries(${EXECUTABLE_NAME} /usr/local/Cellar/fdk-aac/0.1.6/lib/libfdk-aac.dylib)
 #target_link_libraries(${EXECUTABLE_NAME} /usr/local/lib/libx264.dylib)
endif(APPLE)
# Add python dependencies -
# ERROR - It picks up the default version from the machine which is 2.7.10
find_package( PythonInterp 2.7 REQUIRED)
find_package(PythonLibs 2.7 REQUIRED)


message("GURU - python include dirs = ${PYTHON_INCLUDE_DIRS}")
message("GURU - python include dirs = ${PYTHON_LIBRARIES}")

include_directories(${PYTHON_INCLUDE_DIRS})
target_link_libraries(${EXECUTABLE_NAME} ${PYTHON_LIBRARIES})



# Apple creates annoying dylib extension for shared libraries
if(APPLE)
 SET(CMAKE_SHARED_LIBRARY_SUFFIX ".so")
endif(APPLE)
set(CMAKE_SHARED_LIBRARY_PREFIX "")




Thanks a lot for any help in resolving this.


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Is it possible to merge 3 videos with ffmpeg by -f concat and crossfade without video content
10 août 2019, par user3792705I want to merge 3 .mov files quickly without losing any resolution. I want to be able to distinguish the 3 pieces of videos after merge.
"ffmpeg -f concat" does not lose resolution and quick without crossfade.
But, I can’t distinguish 3 videos.
As far as I know ffmpeg filter can be used add crossfade, but it have to use video start/end content to do the merger, which might involve transcoding. It won’t be fast compared with ’concat’, which won’t do transcoding, but simply copying.
Here is the content (ffmpeg -i video.mov) of one of 3 videos :
ffmpeg version 4.1.3 Copyright (c) 2000-2019 the FFmpeg developers
built with Apple LLVM version 10.0.1 (clang-1001.0.46.3)
configuration: --prefix=/usr/local/Cellar/ffmpeg/4.1.3 --enable-shared --enable-pthreads --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags='-I/Library/Java/JavaVirtualMachines/openjdk-12.jdk/Contents/Home/include -I/Library/Java/JavaVirtualMachines/openjdk-12.jdk/Contents/Home/include/darwin' --host-ldflags= --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libbluray --enable-libmp3lame --enable-libopus --enable-librubberband --enable-libsnappy --enable-libtesseract --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librtmp --enable-libspeex --enable-videotoolbox --disable-libjack --disable-indev=jack --enable-libaom --enable-libsoxr
libavutil 56. 22.100 / 56. 22.100
libavcodec 58. 35.100 / 58. 35.100
libavformat 58. 20.100 / 58. 20.100
libavdevice 58. 5.100 / 58. 5.100
libavfilter 7. 40.101 / 7. 40.101
libavresample 4. 0. 0 / 4. 0. 0
libswscale 5. 3.100 / 5. 3.100
libswresample 3. 3.100 / 3. 3.100
libpostproc 55. 3.100 / 55. 3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '..../(edited)/VMEK8375.MOV':
Metadata:
major_brand : qt
minor_version : 0
compatible_brands: qt
creation_time : 2019-06-30T01:28:04.000000Z
com.apple.quicktime.model: iPhone
com.apple.quicktime.software: ZHIYUN
com.apple.quicktime.creationdate: 2019-06-30T09:28:04Z
Duration: 00:00:07.61, start: 0.000000, bitrate: 4386 kb/s
Stream #0:0(und): Video: hevc (Main) (hvc1 / 0x31637668), yuv420p(tv, smpte170m/bt709/bt709), 1280x720, 4329 kb/s, 30.01 fps, 30 tbr, 600 tbn, 600 tbc (default)
Metadata:
creation_time : 2019-06-30T01:28:04.000000Z
handler_name : Core Media Video
encoder : HEVC
Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, mono, fltp, 94 kb/s (default)
Metadata:
creation_time : 2019-06-30T01:28:04.000000Z
handler_name : Core Media AudioIf I don’t care about crossfade with video content, just some ’nice’ black screen in between (It would be nice I add some text, like date + time on the black screen) is good enough for me. Is it possible to do ’concat’ and simple crossfade without video ’content’ ?