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Autres articles (77)
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MediaSPIP v0.2
21 juin 2013, parMediaSPIP 0.2 est la première version de MediaSPIP stable.
Sa date de sortie officielle est le 21 juin 2013 et est annoncée ici.
Le fichier zip ici présent contient uniquement les sources de MediaSPIP en version standalone.
Comme pour la version précédente, il est nécessaire d’installer manuellement l’ensemble des dépendances logicielles sur le serveur.
Si vous souhaitez utiliser cette archive pour une installation en mode ferme, il vous faudra également procéder à d’autres modifications (...) -
Mise à disposition des fichiers
14 avril 2011, parPar défaut, lors de son initialisation, MediaSPIP ne permet pas aux visiteurs de télécharger les fichiers qu’ils soient originaux ou le résultat de leur transformation ou encodage. Il permet uniquement de les visualiser.
Cependant, il est possible et facile d’autoriser les visiteurs à avoir accès à ces documents et ce sous différentes formes.
Tout cela se passe dans la page de configuration du squelette. Il vous faut aller dans l’espace d’administration du canal, et choisir dans la navigation (...) -
Les statuts des instances de mutualisation
13 mars 2010, parPour des raisons de compatibilité générale du plugin de gestion de mutualisations avec les fonctions originales de SPIP, les statuts des instances sont les mêmes que pour tout autre objets (articles...), seuls leurs noms dans l’interface change quelque peu.
Les différents statuts possibles sont : prepa (demandé) qui correspond à une instance demandée par un utilisateur. Si le site a déjà été créé par le passé, il est passé en mode désactivé. publie (validé) qui correspond à une instance validée par un (...)
Sur d’autres sites (14225)
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Memory Leak in c++/cli application
10 décembre 2013, par AnkushI am passing bitmap from my c# app to c++/cli dll that add it to video.
The problem is program slowly leaking memory. I tried _CrtDumpMemoryLeaks() shows me leak of bitmap & another 40 byte leak but i am disposing bitmap.
Can anyone see memory leak, Here is code..Flow :
1) Capture screenshot by takescreenshot()
2) pass it to c++/cli function
3) dispose bitmap
lines from my c# app
Bitmap snap = takescreeshot();
vencoder.AddBitmap(snap);
snap.Dispose();
vencoder.printleak();
private static Bitmap takescreeshot()
{
System.Drawing.Bitmap bitmap = null;
System.Drawing.Graphics graphics = null;
bitmap = new Bitmap
(
System.Windows.Forms.Screen.PrimaryScreen.Bounds.Width,
System.Windows.Forms.Screen.PrimaryScreen.Bounds.Height,
System.Drawing.Imaging.PixelFormat.Format24bppRgb
);
graphics = System.Drawing.Graphics.FromImage(bitmap);
graphics.CopyFromScreen(Screen.PrimaryScreen.Bounds.X, Screen.PrimaryScreen.Bounds.Y, 0, 0, Screen.PrimaryScreen.Bounds.Size);
//Write TimeSpamp
Rectangle rect = new Rectangle(1166, 738, 200, 20);
String datetime= System.String.Format("{0:dd:MM:yy hh:mm:ss}",DateTime.Now);
System.Drawing.Font sysfont = new System.Drawing.Font("Times New Roman", 14, FontStyle.Bold);
graphics.DrawString(datetime, sysfont, Brushes.Red,rect);
//
Grayscale filter = new Grayscale(0.2125, 0.7154, 0.0721);
Bitmap grayImage = filter.Apply(bitmap);
//Dispose
bitmap.Dispose();
graphics.Dispose();
return grayImage;
}now in c++/cli dll
bool VideoEncoder::AddBitmap(Bitmap^ bitmap)
{
BitmapData^ bitmapData = bitmap->LockBits( System::Drawing::Rectangle( 0, 0,bitmap->Width, bitmap->Height ),ImageLockMode::ReadOnly,PixelFormat::Format8bppIndexed);
uint8_t* ptr = reinterpret_cast( static_cast( bitmapData->Scan0 ) );
uint8_t* srcData[4] = { ptr, NULL, NULL, NULL };
int srcLinesize[4] = { bitmapData->Stride, 0, 0, 0 };
pCurrentPicture = CreateFFmpegPicture(pVideoStream->codec->pix_fmt, pVideoStream->codec->width, pVideoStream->codec->height);
sws_scale(pImgConvertCtx, srcData, srcLinesize, 0, bitmap->Height, pCurrentPicture->data, pCurrentPicture->linesize );
bitmap->UnlockBits( bitmapData );
write_video_frame();
bitmapData=nullptr;
ptr=NULL;
return true;
}
AVFrame * VideoEncoder::CreateFFmpegPicture(int pix_fmt, int nWidth, int nHeight)
{
AVFrame *picture = NULL;
uint8_t *picture_buf = NULL;
int size;
picture = avcodec_alloc_frame();
if ( !picture)
{
printf("Cannot create frame\n");
return NULL;
}
size = avpicture_get_size((AVPixelFormat)pix_fmt, nWidth, nHeight);
picture_buf = (uint8_t *) av_malloc(size);
if (!picture_buf)
{
av_free(picture);
printf("Cannot allocate buffer\n");
return NULL;
}
avpicture_fill((AVPicture *)picture, picture_buf,
(AVPixelFormat)pix_fmt, nWidth, nHeight);
return picture;
}
void VideoEncoder::write_video_frame()
{
AVCodecContext* codecContext = pVideoStream->codec;
int out_size, ret = 0;
if ( pFormatContext->oformat->flags & AVFMT_RAWPICTURE )
{
printf( "raw picture must be written" );
}
else
{
out_size = avcodec_encode_video( codecContext, pVideoEncodeBuffer,nSizeVideoEncodeBuffer, pCurrentPicture );
if ( out_size > 0 )
{
AVPacket packet;
av_init_packet( &packet );
if ( codecContext->coded_frame->pts != AV_NOPTS_VALUE )
{
packet.pts = av_rescale_q( packet.pts, codecContext->time_base, pVideoStream->time_base );
}
if ( codecContext->coded_frame->pkt_dts != AV_NOPTS_VALUE )
{
packet.dts = av_rescale_q( packet.dts, codecContext->time_base, pVideoStream->time_base );
}
if ( codecContext->coded_frame->key_frame )
{
packet.flags |= AV_PKT_FLAG_KEY;
}
packet.stream_index = pVideoStream->index;
packet.data = pVideoEncodeBuffer;
packet.size = out_size;
ret = av_interleaved_write_frame( pFormatContext, &packet );
av_free_packet(&packet);
av_freep(pCurrentPicture);
}
else
{
// image was buffered
}
}
if ( ret != 0 )
{
throw gcnew Exception( "Error while writing video frame." );
}
}
void VideoEncoder::printleak()
{
printf("No of leaks: %d",_CrtDumpMemoryLeaks());
printf("\n");
} -
How to convert real pixel values to flutter logical pixel (Density Independent Pixel)
28 mars 2020, par prem pattnaikI am using flutter-ffmpeg package to overlay an image onto the video, and after overlay i am drawing a rectangle over that image but the issue is, ffmpeg overlays image using real pixel data and flutter drawing rectangle using logical pixel, so how can i convert real pixel of ffmpeg to logical pixel of flutter so that i can change overlay dimension of image to match with rectangle.
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Screeching white sound coming while playing audio as a raw stream
27 avril 2020, par Sri Nithya SharabheshwaranandaI. Background



- 

- I am trying to make an application which helps to match subtitles to the audio waveform very accurately at the waveform level, at the word level or even at the character level.
- The audio is expected to be Sanskrit chants (Yoga, rituals etc.) which are extremely long compound words [ example - aṅganyā-sokta-mātaro-bījam is traditionally one word broken only to assist reading ]
- The input transcripts / subtitles might be roughly in sync at the sentence/verse level but surely would not be in sync at the word level.
- The application should be able to figure out points of silence in the audio waveform, so that it can guess the start and end points of each word (or even letter/consonant/vowel in a word), such that the audio-chanting and visual-subtitle at the word level (or even at letter/consonant/vowel level) perfectly match, and the corresponding UI just highlights or animates the exact word (or even letter) in the subtitle line which is being chanted at that moment, and also show that word (or even the letter/consonant/vowel) in bigger font. This app's purpose is to assist learning Sanskrit chanting.
- It is not expected to be a 100% automated process, nor 100% manual but a mix where the application should assist the human as much as possible.













II. Following is the first code I wrote for this purpose, wherein



- 

- First I open a mp3 (or any audio format) file,
- Seek to some arbitrary point in the timeline of the audio file // as of now playing from zero offset
- Get the audio data in raw format for 2 purposes - (1) playing it and (2) drawing the waveform.
- Playing the raw audio data using standard java audio libraries











III. The problem I am facing is, between every cycle there is screeching sound.



- 

- Probably I need to close the line between cycles ? Sounds simple, I can try.
- But I am also wondering if this overall approach itself is correct ? Any tip, guide, suggestion, link would be really helpful.
- Also I just hard coded the sample-rate etc ( 44100Hz etc. ), are these good to set as default presets or it should depend on the input format ?









IV. Here is the code



import com.github.kokorin.jaffree.StreamType;
import com.github.kokorin.jaffree.ffmpeg.FFmpeg;
import com.github.kokorin.jaffree.ffmpeg.FFmpegProgress;
import com.github.kokorin.jaffree.ffmpeg.FFmpegResult;
import com.github.kokorin.jaffree.ffmpeg.NullOutput;
import com.github.kokorin.jaffree.ffmpeg.PipeOutput;
import com.github.kokorin.jaffree.ffmpeg.ProgressListener;
import com.github.kokorin.jaffree.ffprobe.Stream;
import com.github.kokorin.jaffree.ffmpeg.UrlInput;
import com.github.kokorin.jaffree.ffprobe.FFprobe;
import com.github.kokorin.jaffree.ffprobe.FFprobeResult;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicLong;
import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.DataLine;
import javax.sound.sampled.SourceDataLine;


public class FFMpegToRaw {
 Path BIN = Paths.get("f:\\utilities\\ffmpeg-20190413-0ad0533-win64-static\\bin");
 String VIDEO_MP4 = "f:\\org\\TEMPLE\\DeviMahatmyamRecitationAudio\\03_01_Devi Kavacham.mp3";
 FFprobe ffprobe;
 FFmpeg ffmpeg;

 public void basicCheck() throws Exception {
 if (BIN != null) {
 ffprobe = FFprobe.atPath(BIN);
 } else {
 ffprobe = FFprobe.atPath();
 }
 FFprobeResult result = ffprobe
 .setShowStreams(true)
 .setInput(VIDEO_MP4)
 .execute();

 for (Stream stream : result.getStreams()) {
 System.out.println("Stream " + stream.getIndex()
 + " type " + stream.getCodecType()
 + " duration " + stream.getDuration(TimeUnit.SECONDS));
 } 
 if (BIN != null) {
 ffmpeg = FFmpeg.atPath(BIN);
 } else {
 ffmpeg = FFmpeg.atPath();
 }

 //Sometimes ffprobe can't show exact duration, use ffmpeg trancoding to NULL output to get it
 final AtomicLong durationMillis = new AtomicLong();
 FFmpegResult fFmpegResult = ffmpeg
 .addInput(
 UrlInput.fromUrl(VIDEO_MP4)
 )
 .addOutput(new NullOutput())
 .setProgressListener(new ProgressListener() {
 @Override
 public void onProgress(FFmpegProgress progress) {
 durationMillis.set(progress.getTimeMillis());
 }
 })
 .execute();
 System.out.println("audio size - "+fFmpegResult.getAudioSize());
 System.out.println("Exact duration: " + durationMillis.get() + " milliseconds");
 }

 public void toRawAndPlay() throws Exception {
 ProgressListener listener = new ProgressListener() {
 @Override
 public void onProgress(FFmpegProgress progress) {
 System.out.println(progress.getFrame());
 }
 };

 // code derived from : https://stackoverflow.com/questions/32873596/play-raw-pcm-audio-received-in-udp-packets

 int sampleRate = 44100;//24000;//Hz
 int sampleSize = 16;//Bits
 int channels = 1;
 boolean signed = true;
 boolean bigEnd = false;
 String format = "s16be"; //"f32le"

 //https://trac.ffmpeg.org/wiki/audio types
 final AudioFormat af = new AudioFormat(sampleRate, sampleSize, channels, signed, bigEnd);
 final DataLine.Info info = new DataLine.Info(SourceDataLine.class, af);
 final SourceDataLine line = (SourceDataLine) AudioSystem.getLine(info);

 line.open(af, 4096); // format , buffer size
 line.start();

 OutputStream destination = new OutputStream() {
 @Override public void write(int b) throws IOException {
 throw new UnsupportedOperationException("Nobody uses thi.");
 }
 @Override public void write(byte[] b, int off, int len) throws IOException {
 String o = new String(b);
 boolean showString = false;
 System.out.println("New output ("+ len
 + ", off="+off + ") -> "+(showString?o:"")); 
 // output wave form repeatedly

 if(len%2!=0) {
 len -= 1;
 System.out.println("");
 }
 line.write(b, off, len);
 System.out.println("done round");
 }
 };

 // src : http://blog.wudilabs.org/entry/c3d357ed/?lang=en-US
 FFmpegResult result = FFmpeg.atPath(BIN).
 addInput(UrlInput.fromPath(Paths.get(VIDEO_MP4))).
 addOutput(PipeOutput.pumpTo(destination).
 disableStream(StreamType.VIDEO). //.addArgument("-vn")
 setFrameRate(sampleRate). //.addArguments("-ar", sampleRate)
 addArguments("-ac", "1").
 setFormat(format) //.addArguments("-f", format)
 ).
 setProgressListener(listener).
 execute();

 // shut down audio
 line.drain();
 line.stop();
 line.close();

 System.out.println("result = "+result.toString());
 }

 public static void main(String[] args) throws Exception {
 FFMpegToRaw raw = new FFMpegToRaw();
 raw.basicCheck();
 raw.toRawAndPlay();
 }
}





Thank You