javacv从入门到精通进阶——第七章：高级音频处理

心已赠人 2024-03-26 16:11 86阅读 0赞

1.  ## 学习如何使用FFmpeg进行高级音频处理 ##

JavaCV中的FFmpeg库提供了广泛的音频处理功能，可以进行各种高级音频处理，包括但不限于以下内容：

1.  ### 音频裁剪 ###

通过指定音频的起始时间和持续时间来裁剪音频文件，以获得需要的音频片段。

public static void audioClip(String inputPath, String outputPath, double startTime, double duration) throws Exception {
        FFmpegFrameGrabber grabber = new FFmpegFrameGrabber(inputPath);
        grabber.start();
    
        FFmpegFrameRecorder recorder = new FFmpegFrameRecorder(outputPath, grabber.getAudioChannels());
        recorder.setAudioCodec(grabber.getAudioCodec());
        recorder.setAudioBitrate(grabber.getAudioBitrate());
        recorder.setSampleRate(grabber.getSampleRate());
        recorder.start();
    
        double endTime = startTime + duration;
    
        Frame frame;
        while ((frame = grabber.grabFrame()) != null) {
            if (frame.samples == null) {
                break;
            }
    
            double timestamp = grabber.getTimestamp() / 1000000.0;
            if (timestamp >= startTime && timestamp <= endTime) {
                recorder.record(frame);
            }
        }
    
        grabber.stop();
        recorder.stop();
    }

1.  ### 音频削弱： ###

通过调整音频的音量和音频的增益来削弱音频，以减少音频的噪音和失真。

public static void audioReduce(String inputPath, String outputPath, double volume) throws Exception {
        FFmpegFrameGrabber grabber = new FFmpegFrameGrabber(inputPath);
        grabber.start();
    
        FFmpegFrameRecorder recorder = new FFmpegFrameRecorder(outputPath, grabber.getAudioChannels());
        recorder.setAudioCodec(grabber.getAudioCodec());
        recorder.setAudioBitrate(grabber.getAudioBitrate());
        recorder.setSampleRate(grabber.getSampleRate());
        recorder.start();
    
        Frame frame;
        while ((frame = grabber.grabFrame()) != null) {
            if (frame.samples == null) {
                break;
            }
    
            ShortBuffer buffer = (ShortBuffer) frame.samples[0];
            for (int i = 0; i < buffer.limit(); i++) {
                buffer.put(i, (short) (buffer.get(i) * volume));
            }
    
            recorder.record(frame);
        }
    
        grabber.stop();
        recorder.stop();
    }

1.  ### 音频混音： ###

将两个或多个音频文件混合在一起，以创建一个新的混合音频文件。

public static void audioMix(String inputPath1, String inputPath2, String outputPath) throws Exception {
        FFmpegFrameGrabber grabber1 = new FFmpegFrameGrabber(inputPath1);
        grabber1.start();
    
        FFmpegFrameGrabber grabber2 = new FFmpegFrameGrabber(inputP