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The pirate bay depuis la Belgique
1er avril 2013, par
Mis à jour : Avril 2013
Langue : français
Type : Image
Autres articles (102)
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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. -
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Sur d’autres sites (8985)
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Linker error by trying example program with ffmpeg
11 mars, par ChrisI think this might be a stupid question and I'm just blind but that thing is driving me nuts for hours now.
I downloaded ffmpeg and build it. Now I want to try the thing out in a program but I can't setup cmake to link ffmpeg properly and have no idea what is wrong.


The linker always tells me this :


christoph@christoph-ThinkPad-T490:~/develop/ffmpg_example/build$ make
[ 50%] Linking CXX executable test
CMakeFiles/test.dir/main.cxx.o: In function `main':
main.cxx:(.text+0x180): undefined reference to `av_register_all()'
main.cxx:(.text+0x1a7): undefined reference to `avformat_open_input(AVFormatContext**, char const*, AVInputFormat*, AVDictionary**)'
main.cxx:(.text+0x1ce): undefined reference to `avformat_find_stream_info(AVFormatContext*, AVDictionary**)'
main.cxx:(.text+0x206): undefined reference to `av_dump_format(AVFormatContext*, int, char const*, int)'
main.cxx:(.text+0x2bb): undefined reference to `avcodec_find_decoder(AVCodecID)'
main.cxx:(.text+0x2fc): undefined reference to `avcodec_alloc_context3(AVCodec const*)'
main.cxx:(.text+0x316): undefined reference to `avcodec_copy_context(AVCodecContext*, AVCodecContext const*)'
main.cxx:(.text+0x361): undefined reference to `avcodec_open2(AVCodecContext*, AVCodec const*, AVDictionary**)'
main.cxx:(.text+0x377): undefined reference to `av_frame_alloc()'
main.cxx:(.text+0x383): undefined reference to `av_frame_alloc()'
main.cxx:(.text+0x3ba): undefined reference to `avpicture_get_size(AVPixelFormat, int, int)'
main.cxx:(.text+0x3d0): undefined reference to `av_malloc(unsigned long)'
main.cxx:(.text+0x3ff): undefined reference to `avpicture_fill(AVPicture*, unsigned char const*, AVPixelFormat, int, int)'
main.cxx:(.text+0x43d): undefined reference to `sws_getContext(int, int, AVPixelFormat, int, int, AVPixelFormat, int, SwsFilter*, SwsFilter*, double const*)'
main.cxx:(.text+0x465): undefined reference to `av_read_frame(AVFormatContext*, AVPacket*)'
main.cxx:(.text+0x49f): undefined reference to `avcodec_decode_video2(AVCodecContext*, AVFrame*, int*, AVPacket const*)'
main.cxx:(.text+0x4fd): undefined reference to `sws_scale(SwsContext*, unsigned char const* const*, int const*, int, int, unsigned char* const*, int const*)'
main.cxx:(.text+0x545): undefined reference to `av_free_packet(AVPacket*)'
main.cxx:(.text+0x556): undefined reference to `av_free(void*)'
main.cxx:(.text+0x565): undefined reference to `av_frame_free(AVFrame**)'
main.cxx:(.text+0x574): undefined reference to `av_frame_free(AVFrame**)'
main.cxx:(.text+0x580): undefined reference to `avcodec_close(AVCodecContext*)'
main.cxx:(.text+0x58f): undefined reference to `avcodec_close(AVCodecContext*)'
main.cxx:(.text+0x59e): undefined reference to `avformat_close_input(AVFormatContext**)'
collect2: error: ld returned 1 exit status
CMakeFiles/test.dir/build.make:87: recipe for target 'test' failed
make[2]: *** [test] Error 1
CMakeFiles/Makefile2:75: recipe for target 'CMakeFiles/test.dir/all' failed
make[1]: *** [CMakeFiles/test.dir/all] Error 2
Makefile:83: recipe for target 'all' failed
make: *** [all] Error 2


The cmake list looks like this :


cmake_minimum_required(VERSION 3.16)

project(ffmpeg_test)

add_library(avformat STATIC IMPORTED)
set_target_properties(avformat
 PROPERTIES IMPORTED_LOCATION /home/christoph/develop/FFmpeg/build/lib/libavformat.a
)
add_library(avcodec STATIC IMPORTED)
set_target_properties(avcodec
 PROPERTIES IMPORTED_LOCATION /home/christoph/develop/FFmpeg/build/lib/libavcodec.a
)
add_library(swscale STATIC IMPORTED)
set_target_properties(swscale
 PROPERTIES IMPORTED_LOCATION /home/christoph/develop/FFmpeg/build/lib/libswscale.a
)
add_library(avutil STATIC IMPORTED)
set_target_properties(avutil
 PROPERTIES IMPORTED_LOCATION /home/christoph/develop/FFmpeg/build/lib/libavutil.a
)
add_executable(test main.cxx)

target_link_libraries(test PRIVATE
 /home/christoph/develop/FFmpeg/build/lib/libavformat.a
 avcodec
 swscale
 avutil
)
target_include_directories(test PRIVATE /home/christoph/develop/FFmpeg/build/include)


And here are the ffmpeg libs :


christoph@christoph-ThinkPad-T490:~/develop/FFmpeg/build/lib$ ll
total 277840
drwxr-xr-x 3 christoph christoph 4096 Dez 7 23:59 ./
drwxr-xr-x 17 christoph christoph 4096 Dez 7 23:59 ../
-rw-r--r-- 1 christoph christoph 173479270 Dez 7 23:59 libavcodec.a
-rw-r--r-- 1 christoph christoph 2174910 Dez 7 23:59 libavdevice.a
-rw-r--r-- 1 christoph christoph 37992438 Dez 7 23:59 libavfilter.a
-rw-r--r-- 1 christoph christoph 59222040 Dez 7 23:59 libavformat.a
-rw-r--r-- 1 christoph christoph 4759514 Dez 7 23:59 libavutil.a
-rw-r--r-- 1 christoph christoph 695698 Dez 7 23:59 libswresample.a
-rw-r--r-- 1 christoph christoph 6164398 Dez 7 23:59 libswscale.a
drwxr-xr-x 2 christoph christoph 4096 Dez 7 23:59 pkgconfig/


And this is the example code :


#include

#include <libavcodec></libavcodec>avcodec.h>
#include <libavformat></libavformat>avformat.h>
#include <libswscale></libswscale>swscale.h>

// compatibility with newer API
#if LIBAVCODEC_VERSION_INT < AV_VERSION_INT(55,28,1)
#define av_frame_alloc avcodec_alloc_frame
#define av_frame_free avcodec_free_frame
#endif

void SaveFrame(AVFrame *pFrame, int width, int height, int iFrame) {
 FILE *pFile;
 char szFilename[32];
 int y;
 
 // Open file
 sprintf(szFilename, "frame%d.ppm", iFrame);
 pFile=fopen(szFilename, "wb");
 if(pFile==NULL)
 return;
 
 // Write header
 fprintf(pFile, "P6\n%d %d\n255\n", width, height);
 
 // Write pixel data
 for(y=0; ydata[0]+y*pFrame->linesize[0], 1, width*3, pFile);
 
 // Close file
 fclose(pFile);
}

int main(int argc, char *argv[]) {
 // Initalizing these to NULL prevents segfaults!
 AVFormatContext *pFormatCtx = NULL;
 int i, videoStream;
 AVCodecContext *pCodecCtxOrig = NULL;
 AVCodecContext *pCodecCtx = NULL;
 AVCodec *pCodec = NULL;
 AVFrame *pFrame = NULL;
 AVFrame *pFrameRGB = NULL;
 AVPacket packet;
 int frameFinished;
 int numBytes;
 uint8_t *buffer = NULL;
 struct SwsContext *sws_ctx = NULL;

 if(argc < 2) {
 printf("Please provide a movie file\n");
 return -1;
 }
 // Register all formats and codecs
 av_register_all();
 
 // Open video file
 if(avformat_open_input(&pFormatCtx, argv[1], NULL, NULL)!=0)
 return -1; // Couldn't open file
 
 // Retrieve stream information
 if(avformat_find_stream_info(pFormatCtx, NULL)<0)
 return -1; // Couldn't find stream information
 
 // Dump information about file onto standard error
 av_dump_format(pFormatCtx, 0, argv[1], 0);
 
 // Find the first video stream
 videoStream=-1;
 for(i=0; inb_streams; i++)
 if(pFormatCtx->streams[i]->codec->codec_type==AVMEDIA_TYPE_VIDEO) {
 videoStream=i;
 break;
 }
 if(videoStream==-1)
 return -1; // Didn't find a video stream
 
 // Get a pointer to the codec context for the video stream
 pCodecCtxOrig=pFormatCtx->streams[videoStream]->codec;
 // Find the decoder for the video stream
 pCodec=avcodec_find_decoder(pCodecCtxOrig->codec_id);
 if(pCodec==NULL) {
 fprintf(stderr, "Unsupported codec!\n");
 return -1; // Codec not found
 }
 // Copy context
 pCodecCtx = avcodec_alloc_context3(pCodec);
 if(avcodec_copy_context(pCodecCtx, pCodecCtxOrig) != 0) {
 fprintf(stderr, "Couldn't copy codec context");
 return -1; // Error copying codec context
 }

 // Open codec
 if(avcodec_open2(pCodecCtx, pCodec, NULL)<0)
 return -1; // Could not open codec
 
 // Allocate video frame
 pFrame=av_frame_alloc();
 
 // Allocate an AVFrame structure
 pFrameRGB=av_frame_alloc();
 if(pFrameRGB==NULL)
 return -1;

 // Determine required buffer size and allocate buffer
 numBytes=avpicture_get_size(AV_PIX_FMT_RGB24, pCodecCtx->width,
 pCodecCtx->height);
 buffer=(uint8_t *)av_malloc(numBytes*sizeof(uint8_t));
 
 // Assign appropriate parts of buffer to image planes in pFrameRGB
 // Note that pFrameRGB is an AVFrame, but AVFrame is a superset
 // of AVPicture
 avpicture_fill((AVPicture *)pFrameRGB, buffer, AV_PIX_FMT_RGB24,
 pCodecCtx->width, pCodecCtx->height);
 
 // initialize SWS context for software scaling
 sws_ctx = sws_getContext(pCodecCtx->width,
 pCodecCtx->height,
 pCodecCtx->pix_fmt,
 pCodecCtx->width,
 pCodecCtx->height,
 AV_PIX_FMT_RGB24,
 SWS_BILINEAR,
 NULL,
 NULL,
 NULL
 );

 // Read frames and save first five frames to disk
 i=0;
 while(av_read_frame(pFormatCtx, &packet)>=0) {
 // Is this a packet from the video stream?
 if(packet.stream_index==videoStream) {
 // Decode video frame
 avcodec_decode_video2(pCodecCtx, pFrame, &frameFinished, &packet);
 
 // Did we get a video frame?
 if(frameFinished) {
 // Convert the image from its native format to RGB
 sws_scale(sws_ctx, (uint8_t const * const *)pFrame->data,
 pFrame->linesize, 0, pCodecCtx->height,
 pFrameRGB->data, pFrameRGB->linesize);
 
 // Save the frame to disk
 if(++i<=5)
 SaveFrame(pFrameRGB, pCodecCtx->width, pCodecCtx->height, 
 i);
 }
 }
 
 // Free the packet that was allocated by av_read_frame
 av_free_packet(&packet);
 }
 
 // Free the RGB image
 av_free(buffer);
 av_frame_free(&pFrameRGB);
 
 // Free the YUV frame
 av_frame_free(&pFrame);
 
 // Close the codecs
 avcodec_close(pCodecCtx);
 avcodec_close(pCodecCtxOrig);

 // Close the video file
 avformat_close_input(&pFormatCtx);
 
 return 0;
}


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Split a movie so that each GIF is under a certain file size
9 novembre 2014, par Terence EdenProblem
I want to convert a long movie into a series on animated GIFs.
Each GIF needs to be <5MB.
Is there any way to determine how large a GIF will be while it is being encoded ?
Progress So Far
I can split the movie into individual frames :
ffmpeg -i movie.ogv -r 25 frameTemp.%05d.gifI can then use
convertfrom ImageMagick to create GIFs. However, I can’t find a way to determine the likely file size before running the command.Alternatively, I can split the movie into chunks :
ffmpeg -i movie.ogv -vcodec copy -ss 00:00:00 -t 00:20:00 output1.ogvBut I’ve no way of knowing if, when I
convertthe file to a GIF it will be under 5MB.A 10 second scene with a lot of action may be over 5MB (bad !) and a static scene could be under 5MB (not a problem, but not very efficient).
Ideas
I think that what I want to do is convert the entire movie into a GIF, then find a way to split it by file size.
Looking at ImageMagick, I can split a GIF into frames, but I don’t see a way to split it into animated GIFs of a certain size / length.
So, is this possible ?
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Bash : displaying selected output, do not print unnecessary output
2 juillet 2014, par GuillaumeI don’t know if it’s possible :
I’m using ffmpeg and I would like to reduce the output of a command. I have this result :ffmpeg version 2.2.git Copyright (c) 2000-2014 the FFmpeg developers
built on Jun 17 2014 11:08:12 with gcc 4.8 (Ubuntu 4.8.2-19ubuntu1)
configuration: --prefix=/usr/local --enable-gpl --enable-nonfree --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxvid --enable-libvidstab --enable-libx265
libavutil 52. 89.100 / 52. 89.100
libavcodec 55. 67.100 / 55. 67.100
libavformat 55. 43.100 / 55. 43.100
libavdevice 55. 13.101 / 55. 13.101
libavfilter 4. 8.100 / 4. 8.100
libswscale 2. 6.100 / 2. 6.100
libswresample 0. 19.100 / 0. 19.100
libpostproc 52. 3.100 / 52. 3.100
Input #0, hls,applehttp, from 'http://ftvodhdsecz-f.akamaihd.net/i/streaming-adaptatif_france-dom-tom/2014/S26/J7/104904507-20140629-,398,632,934,k.mp4.csmil/index_2_av.m3u8?null=':
Duration: 00:51:05.07, start: 0.100667, bitrate: 0 kb/s
Program 0
Metadata:
variant_bitrate : 0
Stream #0:0: Video: h264 (Main) ([27][0][0][0] / 0x001B), yuv420p, 704x396 [SAR 1:1 DAR 16:9], 25 fps, 25 tbr, 90k tbn, 50 tbc
Stream #0:1: Audio: aac ([15][0][0][0] / 0x000F), 48000 Hz, stereo, fltp, 67 kb/s
Stream #0:2: Data: timed_id3 (ID3 / 0x20334449)
File '/media/path/video.mkv' already exists. Overwrite ? [y/N] y
[matroska @ 0x2958840] Error parsing AAC extradata, unable to determine samplerate.
Output #0, matroska, to '/media/path/video.mkv':
Metadata:
encoder : Lavf55.43.100
Stream #0:0: Video: h264 (H264 / 0x34363248), yuv420p, 704x396 [SAR 1:1 DAR 16:9], q=2-31, 25 fps, 1k tbn, 90k tbc
Stream #0:1: Audio: aac ([255][0][0][0] / 0x00FF), 48000 Hz, stereo, 67 kb/s
Stream mapping:
Stream #0:0 -> #0:0 (copy)
Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
[hls,applehttp @ 0x2864c20] Failed to open segment of playlist 0ate= 844.6kbits/s
frame= 3000 fps=174 q=-1.0 Lsize= 12325kB time=00:02:00.00 bitrate= 841.4kbits/sI just would like to have this 4 informations :
1) Duration: 00:51:05.07, start: 0.100667, bitrate: 0 kb/s
2) File '/media/path/video.mkv' already exists. Overwrite ? [y/N] y
3) Output #0, matroska, to '/media/path/video.mkv':
4) frame= 3000 fps=174 q=-1.0 Lsize= 12325kB time=00:02:00.00 bitrate= 841.4kbits/sI’ve tried the
-v option, but the output is either-v info(this long output), or-v warning, or-v error. There’s not what I would like to have.
I’ve seen this question but the output is totally clear. Can I put an exception for specially string ?
Thanks allEdit : my line in my script is like that :
ffmpeg -i "${M3U2}" -vcodec copy -acodec copy "${Directory}/${PROG}_${ID}.mkv"
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