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Médias (91)
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MediaSPIP Simple : futur thème graphique par défaut ?
26 septembre 2013, par
Mis à jour : Octobre 2013
Langue : français
Type : Video
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avec chosen
13 septembre 2013, par
Mis à jour : Septembre 2013
Langue : français
Type : Image
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sans chosen
13 septembre 2013, par
Mis à jour : Septembre 2013
Langue : français
Type : Image
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config chosen
13 septembre 2013, par
Mis à jour : Septembre 2013
Langue : français
Type : Image
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SPIP - plugins - embed code - Exemple
2 septembre 2013, par
Mis à jour : Septembre 2013
Langue : français
Type : Image
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GetID3 - Bloc informations de fichiers
9 avril 2013, par
Mis à jour : Mai 2013
Langue : français
Type : Image
Autres articles (101)
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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. -
L’agrémenter visuellement
10 avril 2011MediaSPIP est basé sur un système de thèmes et de squelettes. Les squelettes définissent le placement des informations dans la page, définissant un usage spécifique de la plateforme, et les thèmes l’habillage graphique général.
Chacun peut proposer un nouveau thème graphique ou un squelette et le mettre à disposition de la communauté. -
Possibilité de déploiement en ferme
12 avril 2011, parMediaSPIP peut être installé comme une ferme, avec un seul "noyau" hébergé sur un serveur dédié et utilisé par une multitude de sites différents.
Cela permet, par exemple : de pouvoir partager les frais de mise en œuvre entre plusieurs projets / individus ; de pouvoir déployer rapidement une multitude de sites uniques ; d’éviter d’avoir à mettre l’ensemble des créations dans un fourre-tout numérique comme c’est le cas pour les grandes plate-formes tout public disséminées sur le (...)
Sur d’autres sites (7663)
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conversion from cv::mat to avframe, encode in h264 dont writing correctly [on hold]
15 novembre 2014, par danicsi create a method for converting between cv::mat to avframe with PIX_FMT_YUV420P format (oframe format) but _convCtx always return null, whats wrong ? thanks in advance ! ((i solve this)) but i have another probelm in end of this question please
void processToFrame(cv::Mat* _mat, AVFrame* oframe)
{
// Create and allocate the conversion frame.
if (_oframe == nullptr) {
_oframe = avcodec_alloc_frame();
if (_oframe == nullptr)
throw std::runtime_error("Matrix Converter: Could not allocate the output frame.");
avpicture_alloc(reinterpret_cast(_oframe),
PIX_FMT_BGR24, _mat->cols, _mat->rows);
}
avpicture_fill(reinterpret_cast(_oframe),
(uint8_t *)_mat->data,
AV_PIX_FMT_BGR24,
_mat->cols,
_mat->rows);
// Convert the image from its native format to BGR.
if (_convCtx == nullptr) {
_convCtx = sws_getContext(
oframe->width, oframe->height, (enum AVPixelFormat) oframe->format,
_oframe->width, _oframe->height, PIX_FMT_BGR24,
SWS_BICUBIC, nullptr, nullptr, nullptr);
}
if (_convCtx == nullptr)
throw std::runtime_error("Matrix Converter: Unable to initialize the conversion context.");
// Scales the source data according to our SwsContext settings.
if (sws_scale(_convCtx,
_oframe->data, _oframe->linesize, 0, _oframe->height,
oframe->data, oframe->linesize) < 0)
throw std::runtime_error("Matrix Converter: Pixel format conversion not supported.");
}create oframe
void createVideoFile(const char* filename, int w, int h, int codec_id, int fps)
{
/* find the mpeg1 video encoder */
if(codec == nullptr)
{
/* find the mpeg1 video encoder */
codec = avcodec_find_encoder((AVCodecID)codec_id);
if (!codec) {
throw std::runtime_error("codec not found\n");
}
}
if(c == nullptr)
{
c = avcodec_alloc_context3(codec);
if(!c)
{
throw std::runtime_error("Could not allocate video codec context\n");
}
/* put sample parameters */
c->bit_rate = 400000;
/* resolution must be a multiple of two */
c->width = 2 * (w / 2);
c->height = 2 * (h / 2);
/* frames per second */
AVRational ar;
ar.den = 1;
ar.num = fps;
c->time_base= ar; //(AVRational){1,25};
c->gop_size = 10; /* emit one intra frame every ten frames */
c->max_b_frames=1;
c->pix_fmt = 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) {
throw std::runtime_error("Could not open codec\n");
}
f = fopen(filename, "wb");
if (!f) {
throw std::runtime_error("could not open file\n");
}
frame = avcodec_alloc_frame();
if (!frame) {
throw std::runtime_error("Could not allocate video frame\n");
}
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 */
int ret = av_image_alloc(frame->data, frame->linesize, c->width, c->height, c->pix_fmt, 32);
if (ret < 0) {
throw std::runtime_error("Could not allocate raw picture buffer\n");
}
}
}read mat images
void video_encode_example(const cv::Mat& fin)
{
AVPacket pkt;
/* encode 1 second of video */
av_init_packet(&pkt);
pkt.data = NULL; // packet data will be allocated by the encoder
pkt.size = 0;
fflush(stdout);
cv::Mat res;
cv::resize(fin, res, cv::Size(c->width, c->height));
processToFrame(&res, frame);
frame->pts = i;
/* encode the image */
int ret = avcodec_encode_video2(c, &pkt, frame, &got_output);
if (ret < 0) {
throw std::runtime_error("Error encoding frame\n");
}
if (got_output) {
printf("Write frame %3d (size=%5d)\n", i, pkt.size);
fwrite(pkt.data, 1, pkt.size, f);
av_free_packet(&pkt);
}
i++;
}update :
i can solve the conversion problem by setting of _oframe.width = _mat.cols and _oframe.height = _mat.rows, avpicture_alloc dont set this value itself.
now i have the other problem my videowriting class seems write ok because windows slideshow show one of frames, but i cant view video in my players, this is my release function, i dont know whats wrong endcoding or endcoder structure parameter like pts and else.
void video_release()
{
/* get the delayed frames */
for (got_output = 1; got_output; i++) {
fflush(stdout);
int ret = avcodec_encode_video2(c, &pkt, NULL, &got_output);
if (ret < 0) {
throw std::runtime_error("Error encoding frame\n");
}
if (got_output) {
printf("Write frame %3d (size=%5d)\n", i, pkt.size);
fwrite(pkt.data, 1, pkt.size, f);
av_free_packet(&pkt);
}
}
uint8_t endcode[] = { 0, 0, 1, 0xb7 };
/* add sequence end code to have a real mpeg file */
fwrite(endcode, 1, sizeof(endcode), f);
fclose(f);
avcodec_close(c);
av_free(c);
av_freep(&frame->data[0]);
avcodec_free_frame(&frame);
c = nullptr;
codec = nullptr;
frame = nullptr;
if (_convCtx)
sws_freeContext(_convCtx);
if (_oframe) {
//if (_oframe->data)
//av_free(_oframe->data[0]);
av_free(_oframe);
}
_oframe = nullptr;
_convCtx = nullptr;
} -
conversion from cv::mat to avframe
14 novembre 2014, par danicsi create a method for converting between cv::mat to avframe with PIX_FMT_YUV420P format (oframe format) but _convCtx always return null, whats wrong ? thanks in advance !
void processToFrame(cv::Mat* _mat, AVFrame* oframe)
{
// Create and allocate the conversion frame.
if (_oframe == nullptr) {
_oframe = avcodec_alloc_frame();
if (_oframe == nullptr)
throw std::runtime_error("Matrix Converter: Could not allocate the output frame.");
avpicture_alloc(reinterpret_cast(_oframe),
PIX_FMT_BGR24, _mat->cols, _mat->rows);
}
avpicture_fill(reinterpret_cast(_oframe),
(uint8_t *)_mat->data,
AV_PIX_FMT_BGR24,
_mat->cols,
_mat->rows);
// Convert the image from its native format to BGR.
if (_convCtx == nullptr) {
_convCtx = sws_getContext(
oframe->width, oframe->height, (enum AVPixelFormat) oframe->format,
_oframe->width, _oframe->height, PIX_FMT_BGR24,
SWS_BICUBIC, nullptr, nullptr, nullptr);
}
if (_convCtx == nullptr)
throw std::runtime_error("Matrix Converter: Unable to initialize the conversion context.");
// Scales the source data according to our SwsContext settings.
if (sws_scale(_convCtx,
_oframe->data, _oframe->linesize, 0, _oframe->height,
oframe->data, oframe->linesize) < 0)
throw std::runtime_error("Matrix Converter: Pixel format conversion not supported.");
}edit : create oframe
void createVideoFile(const char* filename, int w, int h, int codec_id, int fps)
{
/* find the mpeg1 video encoder */
if(codec == nullptr)
{
/* find the mpeg1 video encoder */
codec = avcodec_find_encoder((AVCodecID)codec_id);
if (!codec) {
throw std::runtime_error("codec not found\n");
}
}
if(c == nullptr)
{
c = avcodec_alloc_context3(codec);
if(!c)
{
throw std::runtime_error("Could not allocate video codec context\n");
}
/* put sample parameters */
c->bit_rate = 400000;
/* resolution must be a multiple of two */
c->width = 2 * (w / 2);
c->height = 2 * (h / 2);
/* frames per second */
AVRational ar;
ar.den = 1;
ar.num = fps;
c->time_base= ar; //(AVRational){1,25};
c->gop_size = 10; /* emit one intra frame every ten frames */
c->max_b_frames=1;
c->pix_fmt = 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) {
throw std::runtime_error("Could not open codec\n");
}
f = fopen(filename, "wb");
if (!f) {
throw std::runtime_error("could not open file\n");
}
frame = avcodec_alloc_frame();
if (!frame) {
throw std::runtime_error("Could not allocate video frame\n");
}
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 */
int ret = av_image_alloc(frame->data, frame->linesize, c->width, c->height, c->pix_fmt, 32);
if (ret < 0) {
throw std::runtime_error("Could not allocate raw picture buffer\n");
}
}
}read mat images
void video_encode_example(const cv::Mat& fin)
{
AVPacket pkt;
/* encode 1 second of video */
av_init_packet(&pkt);
pkt.data = NULL; // packet data will be allocated by the encoder
pkt.size = 0;
fflush(stdout);
cv::Mat res;
cv::resize(fin, res, cv::Size(c->width, c->height));
processToFrame(&res, frame);
frame->pts = i;
/* encode the image */
int ret = avcodec_encode_video2(c, &pkt, frame, &got_output);
if (ret < 0) {
throw std::runtime_error("Error encoding frame\n");
}
if (got_output) {
printf("Write frame %3d (size=%5d)\n", i, pkt.size);
fwrite(pkt.data, 1, pkt.size, f);
av_free_packet(&pkt);
}
i++;
/* get the delayed frames */
/*for (got_output = 1; got_output; i++) {
fflush(stdout);
ret = avcodec_encode_video2(c, &pkt, NULL, &got_output);
if (ret < 0) {
throw std::runtime_error("Error encoding frame\n");
}
if (got_output) {
printf("Write frame %3d (size=%5d)\n", i, pkt.size);
fwrite(pkt.data, 1, pkt.size, f);
av_free_packet(&pkt);
}
}*/
} -
Convert YUV frames into RGBA frames with FFMPEG
28 mai 2015, par Dave_DevI would like to develop an application which would be able to convert YUV frames into RGBA frames using the ffmpeg library.
I have begun writing this code :void Decode::video_encode_example(const char *filename, int codec_id)
{
AVCodec *codec;
AVCodecContext *c= NULL;
int i, ret, x, y, got_output;
FILE *f;
AVFrame *frame;
AVPacket pkt;
uint8_t endcode[] = { 0, 0, 1, 0xb7 };
printf("Encode video file %s\n", filename);
/* find the mpeg1 video encoder */
codec = avcodec_find_encoder((enum AVCodecID)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(2);
}
/* put sample parameters */
c->bit_rate = 400000;
/* resolution must be a multiple of two */
c->width = 352; // Avant c'était du 352x288
c->height = 288;
/* frames per second */
c->time_base = (AVRational){1,25};
/* emit one intra frame every ten frames
* check frame pict_type before passing frame
* to encoder, if frame->pict_type is AV_PICTURE_TYPE_I
* then gop_size is ignored and the output of encoder
* will always be I frame irrespective to gop_size
*/
c->gop_size = 10;
c->max_b_frames = 1;
printf("Avant\n");
c->pix_fmt = PIX_FMT_RGBA;// Avant c'était AV_PIX_FMT_YUV420P
printf("Après\n");
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(3);
}
f = fopen(filename, "wb");
if (!f) {
fprintf(stderr, "Could not open %s\n", filename);
exit(4);
}
frame = avcodec_alloc_frame();// Dans une version plus récente c'est av_frame_alloc
if (!frame) {
fprintf(stderr, "Could not allocate video frame\n");
exit(5);
}
frame->format = c->pix_fmt;
frame->width = c->width;
frame->height = c->height;However, each time I run this application, the following error appears in my Linux terminal :
[mpeg2video @ 0x10c7040] Specified pix_fmt is not supported
Could you help me please ?
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