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Rennes Emotion Map 2010-11
19 octobre 2011, par
Mis à jour : Juillet 2013
Langue : français
Type : Texte
Autres articles (99)
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Sur d’autres sites (12138)
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building a voice recorder using html5 and javascript
16 juillet 2014, par lamaI want to build a voice recorder using HTML5 same as one found in gitHub JSSoundecorder, but what I want is for the user to be able to choose the file format before recording the voice.I can do this using ffmpeg. In other words the user must be able to select the audio format by check box (mp3,wma,pcm) and in the background code, the .wav file usually created by the program instead of displaying it, it should be converted by the format selected then displayed in the new format.this is the ffmpeg code we can use ,but I don’t know how to get the .wav audio file to convert it and show it.please if someone have ideas,or if can find demos I have been looking for weeks.this is the ffmpeg code :
var fileName;
var fileBuffer;
function timeToSeconds(time) {
var parts = time.split(":");
return parseFloat(parts[0]) * 60 * 60 + parseFloat(parts[1]) * 60 + parseFloat(parts[2]) + parseFloat("0." + parts[3]);
}
// create ffmpeg worker
function getFFMPEGWorker() {
// regexps for extracting time from ffmpeg logs
var durationRegexp = /Duration: (.*?), /
var timeRegexp = /time=(.*?) /;
var duration;
var ffmpegWorker = new Worker('worker.js');
var durationLine;
ffmpegWorker.addEventListener('message', function(event) {
var message = event.data;
console.log(message.type);
if (message.type === "ready" && window.File && window.FileList && window.FileReader) {
// script loaded, hide loader
$('#loading').hide();
} else if (message.type == "stdout") {
console.log(message.data);
} else if (message.type == "stderr") {
console.log(message.data);
// try to extract duration
if (durationRegexp.exec(message.data)) {
duration = timeToSeconds(durationRegexp.exec(message.data)[1]);
}
// try to extract time
if (timeRegexp.exec(message.data)) {
var time = timeToSeconds(timeRegexp.exec(message.data)[1]);
if (duration) {
$("#progress").text("Progress: " + Math.floor(time / duration * 100) + "%");
$("#progress").show();
}
}
} else if (message.type == "done") {
var code = message.data.code;
console.log(message.data);
var outFileNames = Object.keys(message.data.outputFiles);
console.log(outFileNames);
if (code == 0 && outFileNames.length) {
var outFileName = outFileNames[0];
var outFileBuffer = message.data.outputFiles[outFileName];
var src = window.URL.createObjectURL(new Blob([outFileBuffer]));
$("#downloadLink").attr('href', src);
$("#download").show();
} else {
$("#error").show();
}
$("#converting").hide();
$("#progress").hide();
}
}, false);
return ffmpegWorker;
}
// create ffmpeg worker
var ffmpegWorker = getFFMPEGWorker();
var ffmpegRunning = false;
$('#convert').click(function() {
// terminate existing worker
if (ffmpegRunning) {
ffmpegWorker.terminate();
ffmpegWorker = getFFMPEGWorker();
}
ffmpegRunning = true;
// display converting animation
$("#converting").show();
$("#error").hide();
// hide download div
$("#download").hide();
// change download file name
var fileNameExt = fileName.substr(fileName.lastIndexOf('.') + 1);
var outFileName = fileName.substr(0, fileName.lastIndexOf('.')) + "." + getOutFormat();
$("#downloadLink").attr("download", outFileName);
$("#downloadLink").text(outFileName);
var arguments = [];
arguments.push("-i");
arguments.push(fileName);
arguments.push("-b:a");
arguments.push(getBitrate());
switch (getOutFormat()) {
case "mp3":
arguments.push("-acodec");
arguments.push("libmp3lame");
arguments.push("out.mp3");
break;
case "wma":
arguments.push("-acodec");
arguments.push("wmav1");
arguments.push("out.asf");
break;
case "pcm":
arguments.push("-f");
arguments.push("s16le");
arguments.push("-acodec");
arguments.push("pcm_s16le");
arguments.push("out.pcm");
}
ffmpegWorker.postMessage({
type: "command",
arguments: arguments,
files: [
{
"name": fileName,
"buffer": fileBuffer
}
]
});
});
function getOutFormat() {
return $('input[name=format]:checked').val();
}
function getBitrate() {
return $('input[name=bitrate]:checked').val();
}
// disable conversion at start
$('#convert').attr('disabled', 'true');
function readInputFile(file) {
// disable conversion for the time of file loading
$('#convert').attr('disabled', 'true');
// load file content
var reader = new FileReader();
reader.onload = function(e) {
$('#convert').removeAttr('disabled');
fileName = file.name;
console.log(fileName);
fileBuffer = e.target.result;
}
reader.readAsArrayBuffer(file);
}
// reset file selector at start
function resetInputFile() {
$("#inFile").wrap('<form>').closest('form').get(0).reset();
$("#inFile").unwrap();
}
resetInputFile();
function handleFileSelect(event) {
var files = event.target.files; // FileList object
console.log(files);
// files is a FileList of File objects. display first file name
file = files[0];
console.log(file);
if (file) {
$("#drop").text("Drop file here");
readInputFile(file);
}
}
// setup input file listeners
document.getElementById('inFile').addEventListener('change', handleFileSelect, false);
</form> -
how to remove PTS gap within a file when transcoding with ffmpeg ?
18 juillet 2017, par jsBaeki have a video which is from rtmp streaming.
Since the broadcasting is on and off frequently,
the archived file has PTS like below
(assume that this is sec)
0—10—20—30—40 120—130—140
there’s discontinuity between 40 and 120 sec.
duration of this file must be 60sec since there’s 80sec gap between 40 120.
but when i transcoded this file, final duration became 140sec with 80sec of pausing parts.
how can i transcode this file without "not existing" 80 sec so that output file became 60sec without redundant pausing 80 sec.
i tried "+getpts" or "+igndts" options but they don’t work at all.
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FFmpeg mux video use libavformat avcodec but output couldn't be played
10 août 2017, par tqnI’m trying write a app that take an input video and crop it to square video and ignore audio stream. Because bad performance if using command, I’m trying to use libavcodec and libavformat to do it. But the output isn’t playable by any video player and duration is 0 although I wrote all frame. Here are my code.
void convert_video(char* input) {
AVFormatContext *pFormatCtx = NULL;
int i, videoStreamIndex;
AVCodecContext *pCodecCtx = NULL;
AVCodec *pCodec = NULL;
AVFrame *pFrame = NULL;
AVFrame *pFrameSquare = NULL;
AVPacket packet, outPacket;
int frameFinished;
int numBytes;
uint8_t *buffer = NULL;
AVCodec *pEncodec = NULL;
AVFormatContext *poFormatCxt = NULL;
MuxOutputStream videoStream = {0}, audioStream = {0};
int tar_w, tar_h;
const enum AVPixelFormat pic_format = AV_PIX_FMT_YUV420P;
const enum AVCodecID codec_id = AV_CODEC_ID_H264;
AVDictionary *optionsDict = NULL;
char output[50];
sprintf(output, "%soutput.mp4", ANDROID_SDCARD);
// Register all formats and codecs
av_register_all();
// Open video file
if(avformat_open_input(&pFormatCtx, input, NULL, NULL)!=0)
return; // Couldn't open file
avformat_alloc_output_context2(&poFormatCxt, NULL, NULL, output);
// Retrieve stream information
if(avformat_find_stream_info(pFormatCtx, NULL)<0)
return; // Couldn't find stream information
// Find the first video stream
videoStreamIndex=-1;
for(i=0; inb_streams; i++)
if(pFormatCtx->streams[i]->codec->codec_type==AVMEDIA_TYPE_VIDEO) {
videoStreamIndex=i;
break;
}
if(videoStreamIndex==-1)
return; // Didn't find a video stream
// Get a pointer to the codec context for the video stream
pCodecCtx = pFormatCtx->streams[videoStreamIndex]->codec;
tar_w = pCodecCtx->width > pCodecCtx->height ? pCodecCtx->height : pCodecCtx->width;
tar_h = tar_w;
// Find the decoder for the video stream
pCodec=avcodec_find_decoder(pCodecCtx->codec_id);
pEncodec = avcodec_find_encoder(codec_id);
add_stream_mux(&videoStream, poFormatCxt, &pEncodec, codec_id, tar_w, tar_h);
videoStream.st[0].time_base = pFormatCtx->streams[videoStreamIndex]->time_base;
videoStream.st[0].codec->time_base = videoStream.st[0].time_base;
videoStream.st[0].codec->time_base.den *= videoStream.st[0].codec->ticks_per_frame;
// add_stream(&audioStream, poFormatCxt, &)
open_video(poFormatCxt, pEncodec, &videoStream, optionsDict);
int ret = avio_open(&poFormatCxt->pb, output, AVIO_FLAG_WRITE);
// Open codec
if(avcodec_open2(pCodecCtx, pCodec, &optionsDict) < 0)
return; // Could not open codec
ret = avformat_write_header(poFormatCxt, &optionsDict);
if (ret != 0) {
ANDROID_LOG("Died");
}
// Allocate video frame
pFrame=av_frame_alloc();
pFrame->format = videoStream.st->codec->pix_fmt;
pFrame->width = pCodecCtx->width;
pFrame->height = pCodecCtx->height;
av_frame_get_buffer(pFrame, 32);
// Allocate an AVFrame structure
pFrameSquare=av_frame_alloc();
if(pFrameSquare==NULL)
return;
// Determine required buffer size and allocate buffer
numBytes=avpicture_get_size(pic_format, tar_w,
tar_h);
buffer = (uint8_t *)av_malloc(numBytes*sizeof(uint8_t));
// Assign appropriate parts of buffer to image planes in pFrameSquare
// Note that pFrameSquare is an AVFrame, but AVFrame is a superset
// of AVPicture
ret = avpicture_fill((AVPicture *)pFrameSquare, buffer, pic_format,
tar_w, tar_h);
if (ret < 0) {
ANDROID_LOG("Can't fill picture");
return;
}
// Read frames and save first five frames to disk
i=0;
ret = av_read_frame(pFormatCtx, &packet);
while(ret >= 0) {
// Is this a packet from the video stream?
if(packet.stream_index == videoStreamIndex) {
// Decode video frame
// av_packet_rescale_ts(&packet, videoStream.st->time_base, videoStream.st->codec->time_base);
avcodec_decode_video2(pCodecCtx, pFrame, &frameFinished,
&packet);
// while (!frameFinished) {
// avcodec_decode_video2(videoStream.st->codec, pFrame, &frameFinished, NULL);
// }
ANDROID_LOG("Trying to decode frame %d with result %d", i, frameFinished);
ret = av_picture_crop((AVPicture*) pFrameSquare, (AVPicture*) pFrame, pic_format, 0, 0);
if (ret < 0) {
ANDROID_LOG("Can't crop image");
}
// av_frame_get_best_effort_timestamp(pFrame);
// av_rescale_q()
if(frameFinished) {
// Save the frame to disk
av_init_packet(&outPacket);
// av_packet_rescale_ts(&outPacket, videoStream.st->codec->time_base, videoStream.st->time_base);
pFrameSquare->width = tar_w;
pFrameSquare->height = tar_h;
pFrameSquare->format = pic_format;
pFrameSquare->pts = ++videoStream.next_pts;
ret = avcodec_encode_video2(videoStream.st->codec, &outPacket, pFrameSquare, &frameFinished);
// int count = 0;
// while (!frameFinished && count++ < 6) {
// ret = avcodec_encode_video2(videoStream.st->codec, &outPacket, NULL, &frameFinished);
// }
if (frameFinished) {
ANDROID_LOG("Writing frame %d", i);
outPacket.stream_index = videoStreamIndex;
av_interleaved_write_frame(poFormatCxt, &outPacket);
}
av_free_packet(&outPacket);
}
}
// Free the packet that was allocated by av_read_frameav_free_packet(&packet);
ret = av_read_frame(pFormatCtx, &packet);
}
ret = av_write_trailer(poFormatCxt);
if (ret < 0) {
ANDROID_LOG("Couldn't write trailer");
} else {
ANDROID_LOG("Video convert finished");
}
// Free the RGB image
av_free(buffer);
av_free(pFrameSquare);
// Free the YUV frame
av_free(pFrame);
// Close the codec
avcodec_close(pCodecCtx);
// avcodec_close(pEncodecCtx);
// Close the video file
avformat_close_input(&pFormatCtx);
return;
}Helper
#define STREAM_DURATION 10.0
#define STREAM_FRAME_RATE 25 /* 25 images/s */
#define STREAM_PIX_FMT AV_PIX_FMT_YUV420P /* default pix_fmt */
/* Add an output stream. */
void add_stream_mux(MuxOutputStream *ost, AVFormatContext *oc,
AVCodec **codec,
enum AVCodecID codec_id, int width, int heigh)
{
AVCodecContext *codecCtx;
int i;
/* find the encoder */
*codec = avcodec_find_encoder(codec_id);
if (!(*codec)) {
fprintf(stderr, "Could not find encoder for '%s'\n",
avcodec_get_name(codec_id));
exit(1);
}
ost->st = avformat_new_stream(oc, *codec);
if (!ost->st) {
fprintf(stderr, "Could not allocate stream\n");
exit(1);
}
ost->st->id = oc->nb_streams-1;
codecCtx = ost->st->codec;
switch ((*codec)->type) {
case AVMEDIA_TYPE_AUDIO:
codecCtx->sample_fmt = (*codec)->sample_fmts ?
(*codec)->sample_fmts[0] : AV_SAMPLE_FMT_FLTP;
codecCtx->bit_rate = 64000;
codecCtx->sample_rate = 44100;
if ((*codec)->supported_samplerates) {
codecCtx->sample_rate = (*codec)->supported_samplerates[0];
for (i = 0; (*codec)->supported_samplerates[i]; i++) {
if ((*codec)->supported_samplerates[i] == 44100)
codecCtx->sample_rate = 44100;
}
}
codecCtx->channels = av_get_channel_layout_nb_channels(codecCtx->channel_layout);
codecCtx->channel_layout = AV_CH_LAYOUT_STEREO;
if ((*codec)->channel_layouts) {
codecCtx->channel_layout = (*codec)->channel_layouts[0];
for (i = 0; (*codec)->channel_layouts[i]; i++) {
if ((*codec)->channel_layouts[i] == AV_CH_LAYOUT_STEREO)
codecCtx->channel_layout = AV_CH_LAYOUT_STEREO;
}
}
codecCtx->channels = av_get_channel_layout_nb_channels(codecCtx->channel_layout);
ost->st->time_base = (AVRational){ 1, codecCtx->sample_rate };
break;
case AVMEDIA_TYPE_VIDEO:
codecCtx->codec_id = codec_id;
codecCtx->bit_rate = 400000;
/* Resolution must be a multiple of two. */
codecCtx->width = width;
codecCtx->height = heigh;
/* timebase: This is the fundamental unit of time (in seconds) in terms
* of which frame timestamps are represented. For fixed-fps content,
* timebase should be 1/framerate and timestamp increments should be
* identical to 1. */
ost->st->time_base = (AVRational){ 1, STREAM_FRAME_RATE };
codecCtx->time_base = ost->st->time_base;
codecCtx->gop_size = 12; /* emit one intra frame every twelve frames at most */
codecCtx->pix_fmt = STREAM_PIX_FMT;
if (codecCtx->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
/* just for testing, we also add B frames */
codecCtx->max_b_frames = 2;
}
if (codecCtx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
/* Needed to avoid using macroblocks in which some coeffs overflow.
* This does not happen with normal video, it just happens here as
* the motion of the chroma plane does not match the luma plane. */
codecCtx->mb_decision = 2;
}
break;
default:
break;
}
/* Some formats want stream headers to be separate. */
if (oc->oformat->flags & AVFMT_GLOBALHEADER)
codecCtx->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;
}
static void open_video(AVFormatContext *oc, AVCodec *codec, MuxOutputStream *ost, AVDictionary *opt_arg)
{
int ret;
AVCodecContext *c = ost->st->codec;
AVDictionary *opt = NULL;
av_dict_copy(&opt, opt_arg, 0);
/* open the codec */
ret = avcodec_open2(c, codec, &opt);
av_dict_free(&opt);
if (ret < 0) {
fprintf(stderr, "Could not open video codec: %s\n", av_err2str(ret));
exit(1);
}
/* allocate and init a re-usable frame */
ost->frame = alloc_picture(c->pix_fmt, c->width, c->height);
if (!ost->frame) {
fprintf(stderr, "Could not allocate video frame\n");
exit(1);
}
/* If the output format is not YUV420P, then a temporary YUV420P
* picture is needed too. It is then converted to the required
* output format. */
ost->tmp_frame = NULL;
if (c->pix_fmt != AV_PIX_FMT_YUV420P) {
ost->tmp_frame = alloc_picture(AV_PIX_FMT_YUV420P, c->width, c->height);
if (!ost->tmp_frame) {
fprintf(stderr, "Could not allocate temporary picture\n");
exit(1);
}
}
}I’m afraid that I set wrong pts or time_base of frame, and also when decoding or encoding, I see that some first frame is lost, frameFinished is 0. See a post that I’ve to flush decoder by
avcodec_decode_video2(videoStream.st->codec, pFrame, &frameFinished, NULL)
but after try a few times, frameFinished still is 0, and withavcodec_encode_video2(videoStream.st->codec, &outPacket, NULL, &frameFinished)
will throw error in next encode frame. So how I can get all frame that lost ? I’m using FFmpeg version 3.0.1