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• Anomalie #3815 : sql_updateq qui ne fait pas de jointure

  10 août 2016, par b b

  Je pense qu’il y a incompréhension de ta part. sql_update attend en premier argument le nom de la table à mettre à jour, cf :

  http://code.spip.net/autodoc/tree/ecrire/base/abstract_sql.php.html#function_sql_updateq

  Alors que sql_allfetsel attend bien une liste de champs à récupérer, cf :

  http://code.spip.net/autodoc/tree/ecrire/base/abstract_sql.php.html#function_sql_allfetsel

  Du coup, j’aurai tendance à penser que le ticket est invalide.

• Are there any libraries on adding effect to audio, like phone, inner monologue, or sounds like a man/woman ? [closed]

  6 mars, par Mathew

  I'm trying to apply different audio effects, such as making audio sound like a phone call. Below is my current approach. As you can see, I'm using multiple filters and simple algorithms to achieve this effect, but the output quality isn't ideal.

  


  Since I need to implement many sound effects/filters, are there any ready-to-use libraries that could help ?

  


  I've looked into FFmpeg filters and noticed mentions of LADSPA/LV2 plugins. Are these viable solutions ? Any other suggestions would be greatly appreciated.

  


  public static void applySceneEffect(String inputPath, String outputPath, int sceneType) {
    LOGGER.info("apply scene effect {} to {}", sceneType, inputPath);

    try (FFmpegFrameGrabber grabber = new FFmpegFrameGrabber(inputPath);
         FFmpegFrameRecorder recorder = new FFmpegFrameRecorder(outputPath, grabber.getAudioChannels())) {

        grabber.setOption("vn", ""); 
        grabber.start();

       
        recorder.setAudioCodec(avcodec.AV_CODEC_ID_PCM_S16LE); 
        recorder.setSampleRate(grabber.getSampleRate());
        recorder.setAudioChannels(grabber.getAudioChannels());
        recorder.setAudioBitrate(grabber.getAudioBitrate());
        recorder.setFormat("wav"); 


        String audioFilter = String.join(",",
                "aresample=8000",      
                "highpass=f=300, lowpass=f=3400",       
                "acompressor=threshold=-15dB:ratio=4:attack=10:release=100", 
                "volume=1.5",          
                "aecho=0.9:0.4:10:0.6"
        );

        FFmpegFrameFilter f1 = new FFmpegFrameFilter(audioFilter, grabber.getAudioChannels());
        f1.setSampleRate(grabber.getSampleRate());
        f1.start();

        recorder.start();

        Random random = new Random();
        double noiseLevel = 0.02; 

   
        while (true) {
            var frame = grabber.grabFrame(true, false, true, true);
            if (frame == null) {
                break;
            }

            ShortBuffer audioBuffer = (ShortBuffer) frame.samples[0];
            short[] audioData = new short[audioBuffer.remaining()];
            audioBuffer.get(audioData);

            applyElectricNoise(audioData, grabber.getSampleRate());

            audioData = applyDistortion(audioData, 1.5, 30000);

            audioBuffer.rewind();
            audioBuffer.put(audioData);
            audioBuffer.flip();


            f1.push(frame); 
            Frame filteredFrame;
            while ((filteredFrame = f1.pull()) != null) {
                recorder.record(filteredFrame); 
            }
        }

        recorder.stop();
        recorder.release();
        grabber.stop();
        grabber.release();
    } catch (FrameGrabber.Exception | FrameRecorder.Exception | FFmpegFrameFilter.Exception e) {
        throw new RuntimeException(e);
    }
}


private static final double NOISE_LEVEL = 0.005; 
private static final int NOISE_FREQUENCY = 60;  

public static void applyElectricNoise(short[] audioData, int sampleRate) {
    Random random = new Random();

    
    for (int i = 0; i < audioData.length; i++) {
        double noise = Math.sin(2 * Math.PI * NOISE_FREQUENCY * i / sampleRate);

        double electricNoise = random.nextGaussian() * NOISE_LEVEL * Short.MAX_VALUE + noise;

        audioData[i] = (short) Math.max(Math.min(audioData[i] + electricNoise, Short.MAX_VALUE), Short.MIN_VALUE); 
    }
}

public static short[] applyTremolo(short[] audioData, int sampleRate, double frequency, double depth) {
    double phase = 0.0;
    double phaseIncrement = 2 * Math.PI * frequency / sampleRate;

    for (int i = 0; i < audioData.length; i++) {
        double modulator = 1.0 - depth + depth * Math.sin(phase); 
        audioData[i] = (short) (audioData[i] * modulator);

        phase += phaseIncrement;
        if (phase > 2 * Math.PI) {
            phase -= 2 * Math.PI;
        }
    }
    return audioData;
}

public static short[] applyDistortion(short[] audioData, double gain, double threshold) {
    for (int i = 0; i < audioData.length; i++) {
        double sample = audioData[i] * gain;

        if (sample > threshold) {
            sample = threshold;
        } else if (sample < -threshold) {
            sample = -threshold;
        }

        audioData[i] = (short) sample;
    }
    return audioData;
}


  


• Convert mp4 video with joining animation mp4 + audio(wav, mp3) using ffmpeg shell command

  24 mai 2021, par Dev-D

  I want to create .mp4 video by joining short animation(.mp4) + audio(wav, mp3) using ffmpeg shell command.

  


  I have tried few commands to join mp4 + audio here is my example command which will generate output video.

  


  ./ffmpeg -y -i ./output/preview-2.mp4 -i ./output/audio-file.mp3 -vf "pad=ceil(iw/2)*2:ceil(ih/2)*2" -r 25 -vcodec libx264 -pix_fmt yuv420p ./output/converted-video.mp4

  


  But I want to play my animation till audio playing. The above FFMPEG command only join my animation(short video .mp4) file with audio and stopped animation playing after duration of short video reached to end (let's say animation file duration is 10seconds and stopped playing after 10 seconds). But my audio is about 3 minutes and I want to re-play the animation video again and again till the audio file duration (3 minutes). Just like a looping effect.