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Médias (9)
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Stereo master soundtrack
17 octobre 2011, par
Mis à jour : Octobre 2011
Langue : English
Type : Audio
-
Elephants Dream - Cover of the soundtrack
17 octobre 2011, par
Mis à jour : Octobre 2011
Langue : English
Type : Image
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#7 Ambience
16 octobre 2011, par
Mis à jour : Juin 2015
Langue : English
Type : Audio
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#6 Teaser Music
16 octobre 2011, par
Mis à jour : Février 2013
Langue : English
Type : Audio
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#5 End Title
16 octobre 2011, par
Mis à jour : Février 2013
Langue : English
Type : Audio
-
#3 The Safest Place
16 octobre 2011, par
Mis à jour : Février 2013
Langue : English
Type : Audio
Autres articles (55)
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Librairies et logiciels spécifiques aux médias
10 décembre 2010, parPour un fonctionnement correct et optimal, plusieurs choses sont à prendre en considération.
Il est important, après avoir installé apache2, mysql et php5, d’installer d’autres logiciels nécessaires dont les installations sont décrites dans les liens afférants. Un ensemble de librairies multimedias (x264, libtheora, libvpx) utilisées pour l’encodage et le décodage des vidéos et sons afin de supporter le plus grand nombre de fichiers possibles. Cf. : ce tutoriel ; FFMpeg avec le maximum de décodeurs et (...) -
Les autorisations surchargées par les plugins
27 avril 2010, parMediaspip core
autoriser_auteur_modifier() afin que les visiteurs soient capables de modifier leurs informations sur la page d’auteurs -
HTML5 audio and video support
13 avril 2011, parMediaSPIP uses HTML5 video and audio tags to play multimedia files, taking advantage of the latest W3C innovations supported by modern browsers.
The MediaSPIP player used has been created specifically for MediaSPIP and can be easily adapted to fit in with a specific theme.
For older browsers the Flowplayer flash fallback is used.
MediaSPIP allows for media playback on major mobile platforms with the above (...)
Sur d’autres sites (9767)
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use ffmpeg encode a video in android
18 août 2014, par user2098010i followed below link for using ffmpeg in android
http://www.roman10.net/how-to-build-ffmpeg-with-ndk-r9/and done ! ndk-build
i need to encode a video captured by phone camera for slow down
i’ve using sample file in ffmpeg/sample...
but i can’t get encoded a video(slow down)output video has 1sec playtime.
few color are displayed !plz... help me
i wanna sleep well...
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 };
__android_log_print(ANDROID_LOG_DEBUG, "BASEBALL", "%s",filename);
/* find the mpeg1 video encoder */
codec = avcodec_find_encoder(CODEC_ID_H263);
if (!codec) {
__android_log_print(ANDROID_LOG_DEBUG, "BASEBALL", "Codec not found");
exit(1);
}
c = avcodec_alloc_context3(codec);
if (!c) {
__android_log_print(ANDROID_LOG_DEBUG, "BASEBALL", "Could not allocate video codec context");
exit(1);
}
/* put sample parameters */
c->bit_rate = 400000;
/* resolution must be a multiple of two */
c->width = 352;
c->height = 288;
/* frames per second */
c->time_base= (AVRational){1,25};
c->gop_size = 10; /* emit one intra frame every ten frames */
c->pix_fmt = AV_PIX_FMT_YUV420P;
// if(codec == AV_CODEC_ID_H264)
// av_opt_set(c->priv_data, "preset", "slow", 0);
/* open it */
if (avcodec_open2(c, codec, NULL) < 0) {
__android_log_print(ANDROID_LOG_DEBUG, "BASEBALL", "Could not open codec");
exit(1);
}
f = fopen(filename, "wb");
if (f == NULL) {
__android_log_print(ANDROID_LOG_DEBUG, "BASEBALL", "Could not open");
exit(1);
}
frame = avcodec_alloc_frame();
if (!frame) {
__android_log_print(ANDROID_LOG_DEBUG, "BASEBALL", "Could not allocate video frame");
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);
if (ret < 0) {
__android_log_print(ANDROID_LOG_DEBUG, "BASEBALL", "Could not allocate raw picture buffer");
exit(1);
}
/* encode 1 second of video */
for(i=0;i<250;i++) {
av_init_packet(&pkt);
pkt.data = NULL; // packet data will be allocated by the encoder
pkt.size = 0;
fflush(stdout);
/* prepare a dummy image */
/* Y */
for(y=0;yheight;y++) {
for(x=0;xwidth;x++) {
frame->data[0][y * frame->linesize[0] + x] = x + y + i * 3;
}
}
/* Cb and Cr */
for(y=0;yheight/2;y++) {
for(x=0;xwidth/2;x++) {
frame->data[1][y * frame->linesize[1] + x] = 128 + y + i * 2;
frame->data[2][y * frame->linesize[2] + x] = 64 + x + i * 5;
}
}
frame->pts = i;
/* encode the image */
ret = avcodec_encode_video2(c, &pkt, frame, &got_output);
if (ret < 0) {
__android_log_print(ANDROID_LOG_DEBUG, "BASEBALL", "Error encoding frame");
exit(1);
}
if (got_output) {
__android_log_print(ANDROID_LOG_DEBUG, "BASEBALL", "encode the image Write frame pktsize %d", pkt.size);
fwrite(pkt.data, 1, pkt.size, f);
av_free_packet(&pkt);
}
}
/* 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) {
__android_log_print(ANDROID_LOG_DEBUG, "BASEBALL", "Error encoding frame");
fprintf(stderr, "Error encoding frame\n");
exit(1);
}
if (got_output) {
__android_log_print(ANDROID_LOG_DEBUG, "BASEBALL", "get the delayed frames Write frame pktsize %d", pkt.size);
fwrite(pkt.data, 1, pkt.size, f);
av_free_packet(&pkt);
}
}
/* 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); -
FFMPEG avformat_write_header changing my stream time_base
24 avril 2015, par cesarpachonI am muxing video using ffmpeg 2.1.3 with libavcodec 55.39.101 (forced to that version because is the one available in google-chrome PNACL port project). all my frames seems to have bad the time. they try to be rendered all at once at the beggining of the video when playing it.
I am setting the stream time base to 1/25, but just after calling avformat_write_header, it has the value of -18082736/1.
in each frame, when I print the stream time_base it says 1/12800, while the time_base of codec is always ok (1/25).console log before and after av_format_write_header :
before avformat_write_header stream time_base: 1/25
after avformat_write_header ret 0 stream time_base: -18082736/1the code (abreviated to keep the post short, all calls in the original version had error checking) :
AVCodecContext *codecContext;
AVCodec * codec = avcodec_find_encoder(codec_id);
myOutputStream->stream = avformat_new_stream(outputFormatContext, *codec);
myOutputStream->stream->id = outputFormatContext->nb_streams-1;
codecContext = myOutputStream->stream->codec;
codecContext->codec_id = codec_id;
codecContext->bit_rate = 400000;
codecContext->width = width;
codecContext->height = height;
myOutputStream->stream->time_base = (AVRational){ 1, 25 };
codecContext->time_base = myOutputStream->stream->time_base;
codecContext->gop_size = 12;
codecContext->pix_fmt = AV_PIX_FMT_YUV420P;
AVDictionary *opt = NULL;
av_dict_copy(&opt, opt_arg, 0);
ret = avcodec_open2(codecContext, codec, &opt);
av_dict_free(&opt);
myOutputStream->frame = alloc_picture(codecContext->pix_fmt, codecContext->width, codecContext->height);
myOutputStream->tmp_frame = alloc_picture(AV_PIX_FMT_YUV420P, codecContext->width, codecContext->height);
//before: printing g_outputContext->stream time_base here
ret = avformat_write_header(g_outputContext, &opt);
//after: printing g_outputContext->stream time_base hereIf I run ffmpeg -i on the final video, I got this (why duration is zero ?) :
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'test4.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2mp41
encoder : Lavf55.19.104
Duration: 00:00:00.05, start: 0.000000, bitrate: 99549 kb/s
Stream #0:0(und): Video: mpeg4 (Simple Profile) (mp4v / 0x7634706D), yuv420p, 800x600 [SAR 1:1 DAR 4:3], 463106 kb/s, 12800 fps, 12800 tbr, 12800 tbn, 25 tbc (default)
Metadata:
handler_name : VideoHandler -
Decoding then re-encoding frames in reverse order with ffmpeg
21 août 2014, par user3875919I am pretty new to ffmpeg, and now I want to decode the frames and encode it back in reverse order. I have used this tutorial for decoding the video and this example to encode it back. I can decode the frames properly, but when I re-encode it, I get a dummy image rather than clear video. How can I get the actual reversed video ?
static void video_encode_example(const char *filename, int codec_id)
{
AVCodec *codec;
AVCodecContext *c= NULL;
int i, ret, x, y, got_output;
FILE *f;
struct SwsContext *sws_ctx = NULL;
AVFrame *frame;
AVFrame *frameRGB = NULL;
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(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 = 352;
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;
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);
}
f = fopen(filename, "wb");
if (!f) {
fprintf(stderr, "Could not open %s\n", filename);
exit(1);
}
frame = av_frame_alloc();
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);
if (ret < 0) {
fprintf(stderr, "Could not allocate raw picture buffer\n");
exit(1);
}
/* encode 1 second of video */
for (i = 0; i < 25; i++) {
av_init_packet(&pkt);
pkt.data = NULL; // packet data will be allocated by the encoder
pkt.size = 0;
fflush(stdout);
/* prepare a dummy image */
/* Y */
for (y = 0; y < c->height; y++) {
for (x = 0; x < c->width; x++) {
frame->data[0][y * frame->linesize[0] + x] = x + y + i * 3;
}
}
/* Cb and Cr */
for (y = 0; y < c->height/2; y++) {
for (x = 0; x < c->width/2; x++) {
frame->data[1][y * frame->linesize[1] + x] = 128 + y + i * 2;
frame->data[2][y * frame->linesize[2] + x] = 64 + x + i * 5;
}
}
frame->pts = i;
/* encode the image */
ret = avcodec_encode_video2(c, &pkt, frame, &got_output);
if (ret < 0) {
fprintf(stderr, "Error encoding frame\n");
exit(1);
}
if (got_output) {
// Convert the image from its native format to RGB
sws_scale
(
sws_ctx,
(uint8_t const * const *)frame->data,
frame->linesize,
0,
c->height,
frameRGB->data,
frameRGB->linesize
);
printf("Write frame %3d (size=%5d)\n", i, pkt.size);
fwrite(pkt.data, 1, pkt.size, f);
av_free_packet(&pkt);
}
}
/* 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) {
fprintf(stderr, "Error encoding frame\n");
exit(1);
}
if (got_output) {
printf("Write frame %3d (size=%5d)\n", i, pkt.size);
fwrite(pkt.data, 1, pkt.size, f);
av_free_packet(&pkt);
}
}
/* 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]);
av_frame_free(&frame);
printf("\n");
}
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