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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 (98)
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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 (...) -
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. -
List of compatible distributions
26 avril 2011, parThe table below is the list of Linux distributions compatible with the automated installation script of MediaSPIP. Distribution nameVersion nameVersion number Debian Squeeze 6.x.x Debian Weezy 7.x.x Debian Jessie 8.x.x Ubuntu The Precise Pangolin 12.04 LTS Ubuntu The Trusty Tahr 14.04
If you want to help us improve this list, you can provide us access to a machine whose distribution is not mentioned above or send the necessary fixes to add (...)
Sur d’autres sites (10074)
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Save video clip from longer video between two timestamps in Python cv2
14 juin 2022, par Elizabeth OrricoI have an hour-long video that I would like to save a clip between two timestamps— say, 11:20-11:35. Is the best way to do this frame-by-frame, or is there a better way ?


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Revision 97d1f1aaae : Rework scan order fetch logic for decoder Save redundant call for getting predi
7 juillet 2015, par Jingning HanChanged Paths :
Modify /vp9/decoder/vp9_decodeframe.c
Modify /vp9/decoder/vp9_detokenize.c
Modify /vp9/decoder/vp9_detokenize.h
Rework scan order fetch logic for decoderSave redundant call for getting prediction mode to obtain scan
order for detokenization.Change-Id : I0683ef119f1579d1261ed5d59052a1745b68ef6f
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C++, FFmpeg, save AVPacket infomation into videostate structure in ffplay.c
28 mai 2015, par YoohooI am currently working on a project that tests video streaming. In the project, video stream is encoded with H.264 before send and decoded after receive, using FFmpeg codec and functions.
I can encode video stream by
init_video_encode(AV_CODEC_ID_H264);
where
static void init_video_encode(AVCodecID codec_id){
codec = avcodec_find_encoder(codec_id);
if (!codec) {
fprintf(stderr, "Codec not found\n");
exit(1);
}
c = avcodec_alloc_context3(codec);
if (!c) {
fprintf(stderr, "Could not allocate video codec context\n");
exit(1);
}
/* put sample parameters */
c->bit_rate = 400000;
/* resolution must be a multiple of two */
c->width = 640;
c->height = 480;
/* frames per second */
c->time_base= (AVRational){1,25};
c->gop_size = 10; /* emit one intra frame every ten frames */
c->max_b_frames=max_f;
c->pix_fmt = AV_PIX_FMT_YUV420P;
if(codec_id == AV_CODEC_ID_H264)
av_opt_set(c->priv_data, "preset", "slow", 0);
/* open it */
if (avcodec_open2(c, codec, NULL) < 0) {
fprintf(stderr, "Could not open codec\n");
exit(1);
}
frame = avcodec_alloc_frame();
if (!frame) {
fprintf(stderr, "Could not allocate video frame\n");
exit(1);
}
frame->format = c->pix_fmt;
frame->width = c->width;
frame->height = c->height;
/* the image can be allocated by any means and av_image_alloc() is
* just the most convenient way if av_malloc() is to be used */
ret = av_image_alloc(frame->data, frame->linesize, c->width, c->height,
c->pix_fmt, 32);
/* get the delayed frames */
if (ret < 0) {
fprintf(stderr, "Could not allocate raw picture buffer\n");
exit(1);
}
av_init_packet(&pkt);
//}
pkt.data = NULL; // packet data will be allocated by the encoder
pkt.size = 0;
//cout<<"\nBefore YUV\n";
if(count == 0)
read_yuv420(frame->data[0]);
count ++;
// cout<<"\nAfter YUV\n";
if(count == SUBSITY) {
count = 0;
}
frame->pts = i++;
/* encode the image */
ret = avcodec_encode_video2(c, &pkt, frame, &got_output);
if (ret < 0) {
fprintf(stderr, "Error encoding frame\n");
return -1;
}
//cout<<"\nRecord the Video\n";
if (got_output) {
//printf("Write frame %3d (size=%5d)\n", i, pkt.size);
//cout<<"\nBefore Memcpy\n\n\n";
memcpy(inbufout+totalSize,pkt.data,pkt.size);
//cout<<"\nAfter Memcpy\n\n\n";
totalSize+=pkt.size;The video encoder works very well, if I write the encoded packet into a .h264 file, it can be played. But at the decoder side, I cannot decode the received packet with :
codec = avcodec_find_decoder(AV_CODEC_ID_H264);
if (!codec) {
fprintf(stderr, "Codec not found\n");
exit(1);
}
c = avcodec_alloc_context3(codec);
if (!c) {
fprintf(stderr, "Could not allocate video codec context\n");
exit(1);
}
if(codec->capabilities&CODEC_CAP_TRUNCATED)
c->flags|= CODEC_FLAG_TRUNCATED;
/* open it */
if (avcodec_open2(c, codec, NULL) < 0) {
fprintf(stderr, "Could not open codec\n");
exit(1);
}
frame = avcodec_alloc_frame();
if (!frame) {
fprintf(stderr, "Could not allocate video frame\n");
exit(1);
}
len = avcodec_decode_video2(avctx, frame, &got_frame, pkt);
if (len < 0) {
fprintf(stderr, "Error while decoding frame %d\n", *frame_count);
return len;
}The reason of failure is lacking parser, I have tried to build a parser but failed......
Therefore I am wondering using ffplay.c as a header file in my receiver program so that I can use it as the decoder and player.
I have took a look at ffplay.c, it actually fetch file into a videostate structure and processing it. The fetching part is from line 3188 of ffplay.c :
VideoState *is;
is = av_mallocz(sizeof(VideoState));
if (!is)
return NULL;
av_strlcpy(is->filename, filename, sizeof(is->filename));
is->iformat = iformat;
is->ytop = 0;
is->xleft = 0;
/* start video display */
if (frame_queue_init(&is->pictq, &is->videoq, VIDEO_PICTURE_QUEUE_SIZE, 1) < 0)
goto fail;
if (frame_queue_init(&is->subpq, &is->subtitleq, SUBPICTURE_QUEUE_SIZE, 0) < 0)
goto fail;
if (frame_queue_init(&is->sampq, &is->audioq, SAMPLE_QUEUE_SIZE, 1) < 0)
goto fail;
packet_queue_init(&is->videoq);
packet_queue_init(&is->audioq);
packet_queue_init(&is->subtitleq);
is->continue_read_thread = SDL_CreateCond();
init_clock(&is->vidclk, &is->videoq.serial);
init_clock(&is->audclk, &is->audioq.serial);
init_clock(&is->extclk, &is->extclk.serial);
is->audio_clock_serial = -1;
is->av_sync_type = av_sync_type;
is->read_tid = SDL_CreateThread(read_thread, is);
if (!is->read_tid) {
fail:
stream_close(is);
return NULL;
}Now instead of fetching file, I want to modify ffplay.c code so that let it fetch the received packet, I can save received packet to AVPacket by
static AVPacket avpkt;
avpkt.data = inbuf;My question is : how to put AVPacket information into videostate structure ?