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Autres articles (40)
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Websites made with MediaSPIP
2 mai 2011, parThis page lists some websites based on MediaSPIP.
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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. -
Creating farms of unique websites
13 avril 2011, parMediaSPIP platforms can be installed as a farm, with a single "core" hosted on a dedicated server and used by multiple websites.
This allows (among other things) : implementation costs to be shared between several different projects / individuals rapid deployment of multiple unique sites creation of groups of like-minded sites, making it possible to browse media in a more controlled and selective environment than the major "open" (...)
Sur d’autres sites (6385)
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seeking with av_seek_frame returns invalid data
27 juin 2016, par mtadmkBased on dranger tutorial I’m trying to implement seeking in video file. Problem is with seeking to beginning milliseconds - it always returns 0 when seeking backward, or some place in file (based on file format).
I.e. with this video file and seeking forward to 500 pts there is always 6163 pts returned. Seeking backward to 500 is always returning 0. I have no idea why.
Code to do this :
import java.util.Arrays;
import java.util.List;
import org.bytedeco.javacpp.BytePointer;
import org.bytedeco.javacpp.DoublePointer;
import org.bytedeco.javacpp.PointerPointer;
import org.bytedeco.javacpp.avcodec;
import org.bytedeco.javacpp.avformat;
import org.bytedeco.javacpp.avutil;
import org.bytedeco.javacpp.swscale;
import static org.bytedeco.javacpp.avcodec.av_free_packet;
import static org.bytedeco.javacpp.avcodec.avcodec_close;
import static org.bytedeco.javacpp.avcodec.avcodec_decode_video2;
import static org.bytedeco.javacpp.avcodec.avcodec_find_decoder;
import static org.bytedeco.javacpp.avcodec.avcodec_flush_buffers;
import static org.bytedeco.javacpp.avcodec.avcodec_open2;
import static org.bytedeco.javacpp.avcodec.avpicture_fill;
import static org.bytedeco.javacpp.avcodec.avpicture_get_size;
import static org.bytedeco.javacpp.avformat.AVSEEK_FLAG_BACKWARD;
import static org.bytedeco.javacpp.avformat.av_dump_format;
import static org.bytedeco.javacpp.avformat.av_read_frame;
import static org.bytedeco.javacpp.avformat.av_register_all;
import static org.bytedeco.javacpp.avformat.av_seek_frame;
import static org.bytedeco.javacpp.avformat.avformat_close_input;
import static org.bytedeco.javacpp.avformat.avformat_find_stream_info;
import static org.bytedeco.javacpp.avformat.avformat_open_input;
import static org.bytedeco.javacpp.avutil.AVMEDIA_TYPE_VIDEO;
import static org.bytedeco.javacpp.avutil.AV_PIX_FMT_RGB24;
import static org.bytedeco.javacpp.avutil.AV_TIME_BASE;
import static org.bytedeco.javacpp.avutil.av_frame_alloc;
import static org.bytedeco.javacpp.avutil.av_frame_get_best_effort_timestamp;
import static org.bytedeco.javacpp.avutil.av_free;
import static org.bytedeco.javacpp.avutil.av_make_q;
import static org.bytedeco.javacpp.avutil.av_malloc;
import static org.bytedeco.javacpp.avutil.av_q2d;
import static org.bytedeco.javacpp.avutil.av_rescale_q;
import static org.bytedeco.javacpp.swscale.SWS_BILINEAR;
import static org.bytedeco.javacpp.swscale.sws_getContext;
import static org.bytedeco.javacpp.swscale.sws_scale;
public class SeekTest1 {
private avformat.AVFormatContext videoFile;
private final avcodec.AVPacket framePacket = new avcodec.AVPacket();
private avcodec.AVCodecContext videoCodec;
private avutil.AVFrame yuvFrame;
private swscale.SwsContext scalingContext;
private avutil.AVFrame rgbFrame;
private int streamId;
private long lastTime;
public static void main(String[] args) {
if (args.length > 0) {
new SeekTest1().start(args[0]);
} else {
new SeekTest1().start("/path/to/file");
}
}
private void start(String path) {
init(path);
//test for forward
// List<integer> seekPos = Arrays.asList(0, 100, 0, 200, 0, 300, 0, 400, 0, 500, 0, 600, 0, 700);
//test for backward
List<integer> seekPos = Arrays.asList(10000, 8000, 10000, 7000, 10000, 6000, 10000, 4000, 10000, 2000, 10000, 1000, 10000, 200);
seekPos.forEach(seekPosition -> {
readFrame();
seek(seekPosition);
});
readFrame();
cleanUp();
}
long seek(long seekPosition) {
final avutil.AVRational timeBase = fetchTimeBase();
long timeInBaseUnit = fetchTimeInBaseUnit(seekPosition, timeBase);
//changing flag to AVSEEK_FLAG_ANY does not change behavior
int flag = 0;
if (timeInBaseUnit < lastTime) {
flag = AVSEEK_FLAG_BACKWARD;
System.out.println("seeking backward to " + timeInBaseUnit);
} else {
System.out.println("seeking forward to " + timeInBaseUnit);
}
avcodec_flush_buffers(videoCodec);
av_seek_frame(videoFile, streamId, timeInBaseUnit, flag);
return timeInBaseUnit;
}
private long fetchTimeInBaseUnit(long seekPositionMillis, avutil.AVRational timeBase) {
return av_rescale_q((long) (seekPositionMillis / 1000.0 * AV_TIME_BASE), av_make_q(1, AV_TIME_BASE), timeBase);
}
private void readFrame() {
while (av_read_frame(videoFile, framePacket) >= 0) {
if (framePacket.stream_index() == streamId) {
// Decode video frame
final int[] frameFinished = new int[1];
avcodec_decode_video2(this.videoCodec, yuvFrame, frameFinished, framePacket);
if (frameFinished[0] != 0) {
av_free_packet(framePacket);
long millis = produceFinishedFrame();
System.out.println("produced time " + millis);
break;
}
}
av_free_packet(framePacket);
}
}
private long produceFinishedFrame() {
sws_scale(scalingContext, yuvFrame.data(), yuvFrame.linesize(), 0,
videoCodec.height(), rgbFrame.data(), rgbFrame.linesize());
final long pts = av_frame_get_best_effort_timestamp(yuvFrame);
final double timeBase = av_q2d(fetchTimeBase());
final long foundMillis = (long) (pts * 1000 * timeBase);
lastTime = foundMillis;
return foundMillis;
}
private avutil.AVRational fetchTimeBase() {
return videoFile.streams(streamId).time_base();
}
private void init(String videoPath) {
final avformat.AVFormatContext videoFile = new avformat.AVFormatContext(null);
av_register_all();
if (avformat_open_input(videoFile, videoPath, null, null) != 0) throw new RuntimeException("unable to open");
if (avformat_find_stream_info(videoFile, (PointerPointer) null) < 0) throw new RuntimeException("Couldn't find stream information");
av_dump_format(videoFile, 0, videoPath, 0);
final int streamId = findFirstVideoStream(videoFile);
final avcodec.AVCodecContext codec = videoFile.streams(streamId).codec();
final avcodec.AVCodec pCodec = avcodec_find_decoder(codec.codec_id());
if (pCodec == null) throw new RuntimeException("Unsupported codec");
if (avcodec_open2(codec, pCodec, (avutil.AVDictionary) null) < 0) throw new RuntimeException("Could not open codec");
final avutil.AVFrame yuvFrame = av_frame_alloc();
final avutil.AVFrame rgbFrame = av_frame_alloc();
if (rgbFrame == null) throw new RuntimeException("Can't allocate avframe");
final int numBytes = avpicture_get_size(AV_PIX_FMT_RGB24, codec.width(), codec.height());
final BytePointer frameBuffer = new BytePointer(av_malloc(numBytes));
final swscale.SwsContext swsContext = sws_getContext(codec.width(), codec.height(), codec.pix_fmt(), codec.width(), codec.height(),
AV_PIX_FMT_RGB24, SWS_BILINEAR, null, null, (DoublePointer) null);
avpicture_fill(new avcodec.AVPicture(rgbFrame), frameBuffer, AV_PIX_FMT_RGB24, codec.width(), codec.height());
this.videoFile = videoFile;
this.videoCodec = codec;
this.yuvFrame = yuvFrame;
this.scalingContext = swsContext;
this.rgbFrame = rgbFrame;
this.streamId = streamId;
}
private static int findFirstVideoStream(avformat.AVFormatContext videoFile) {
int videoStream = -1;
for (int i = 0; i < videoFile.nb_streams(); i++) {
if (videoFile.streams(i).codec().codec_type() == AVMEDIA_TYPE_VIDEO) {
videoStream = i;
break;
}
}
if (videoStream == -1) throw new RuntimeException("Didn't find video stream");
return videoStream;
}
private void cleanUp() {
av_free(this.rgbFrame);
av_free(yuvFrame);
avcodec_close(videoCodec);
avformat_close_input(videoFile);
}
}
</integer></integer>As input arg should be provided file from above.
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Revision 1161055129 : Be consistent with SAD values SAD returns unsigned values. Make all the declara
26 juin 2012, par JohannChanged Paths : Modify /test/sad_test.cc Modify /vp8/common/mfqe.c Modify /vp8/common/rtcd_defs.sh Modify /vp8/common/sad_c.c Modify /vp8/common/variance.h Modify /vp8/common/x86/sad_sse2.asm Modify /vp8/encoder/mcomp.c Modify /vp8/encoder/rdopt.c Be consistent with SAD (...)
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Google Speech - Streaming Request Returns EOF
9 octobre 2017, par JoshUsing Go, I’m taking a RTMP stream, transcoding it to FLAC (using ffmpeg) and attempting to stream to Google’s Speech API to transcribe the audio. However, I keep getting
EOF
errors when sending the data. I can’t find any information on this error in the docs so I’m not exactly sure what’s causing it.I’m chunking the received data into 3s clips (length isn’t relevant as long as it’s less than the maximum length of a streaming recognition request).
Here is the core of my code :
func main() {
done := make(chan os.Signal)
received := make(chan []byte)
go receive(received)
go transcribe(received)
signal.Notify(done, os.Interrupt, syscall.SIGTERM)
select {
case <-done:
os.Exit(0)
}
}
func receive(received chan<- []byte) {
var b bytes.Buffer
stdout := bufio.NewWriter(&b)
cmd := exec.Command("ffmpeg", "-i", "rtmp://127.0.0.1:1935/live/key", "-f", "flac", "-ar", "16000", "-")
cmd.Stdout = stdout
if err := cmd.Start(); err != nil {
log.Fatal(err)
}
duration, _ := time.ParseDuration("3s")
ticker := time.NewTicker(duration)
for {
select {
case <-ticker.C:
stdout.Flush()
log.Printf("Received %d bytes", b.Len())
received <- b.Bytes()
b.Reset()
}
}
}
func transcribe(received <-chan []byte) {
ctx := context.TODO()
client, err := speech.NewClient(ctx)
if err != nil {
log.Fatal(err)
}
stream, err := client.StreamingRecognize(ctx)
if err != nil {
log.Fatal(err)
}
// Send the initial configuration message.
if err = stream.Send(&speechpb.StreamingRecognizeRequest{
StreamingRequest: &speechpb.StreamingRecognizeRequest_StreamingConfig{
StreamingConfig: &speechpb.StreamingRecognitionConfig{
Config: &speechpb.RecognitionConfig{
Encoding: speechpb.RecognitionConfig_FLAC,
LanguageCode: "en-GB",
SampleRateHertz: 16000,
},
},
},
}); err != nil {
log.Fatal(err)
}
for {
select {
case data := <-received:
if len(data) > 0 {
log.Printf("Sending %d bytes", len(data))
if err := stream.Send(&speechpb.StreamingRecognizeRequest{
StreamingRequest: &speechpb.StreamingRecognizeRequest_AudioContent{
AudioContent: data,
},
}); err != nil {
log.Printf("Could not send audio: %v", err)
}
}
}
}
}Running this code gives this output :
2017/10/09 16:05:00 Received 191704 bytes
2017/10/09 16:05:00 Saving 191704 bytes
2017/10/09 16:05:00 Sending 191704 bytes
2017/10/09 16:05:00 Could not send audio: EOF
2017/10/09 16:05:03 Received 193192 bytes
2017/10/09 16:05:03 Saving 193192 bytes
2017/10/09 16:05:03 Sending 193192 bytes
2017/10/09 16:05:03 Could not send audio: EOF
2017/10/09 16:05:06 Received 193188 bytes
2017/10/09 16:05:06 Saving 193188 bytes
2017/10/09 16:05:06 Sending 193188 bytes // Notice that this doesn't error
2017/10/09 16:05:09 Received 191704 bytes
2017/10/09 16:05:09 Saving 191704 bytes
2017/10/09 16:05:09 Sending 191704 bytes
2017/10/09 16:05:09 Could not send audio: EOFNotice that not all of the
Send
s fail.Could anyone point me in the right direction here ? Is it something to do with the FLAC headers or something ? I also wonder if maybe resetting the buffer causes some of the data to be dropped (i.e. it’s a non-trivial operation that actually takes some time to complete) and it doesn’t like this missing information ?
Any help would be really appreciated.