概述:java 使用 javacv 视频截帧, 跳到指定帧截图, 从视频中抽取音频, 音频分割为多段1 依赖:dependency groupIdorg.bytedeco/groupId artifactIdjavacv/artifactId version1.5.7/version /dependency dependency groupIdorg.bytedeco/groupId artifactIdjavacv-platform/artifactId version1.5.7/version /dependency注意: javacv中mat与tf模型中mat格式不兼容。如果需要调用TensorFlow等传Mat需要将javacv中的opencv排掉引nexus上opencv包并加载opencv lib包。2 视频截帧1) 视频连续截帧/间隔截帧此种方式为从头开始循环视频每一帧, 适用于连续或如每10帧截一帧图等比较密集的连续截帧.//Param : path:视频path; dir:截帧保存文件夹,也可以直接使用mat不保存图片; frameInterval:每多少帧截一帧 public void grabFrameInterval(String path, String dir, int frameInterval) throws Exception { logger.info(视频截帧 source sourceFile: {}, path); try (FFmpegFrameGrabber frameGrabber new FFmpegFrameGrabber(path)) { frameGrabber.start(); int lengthInFrames frameGrabber.getLengthInFrames(); logger.info(视频截帧 开始, 视频共 {} 帧, 预计截帧: {}张, lengthInFrames, lengthInFrames/frameInterval); int frameCount -1; //第一帧不截, 从第二帧开始截 Frame frame; while ((frame frameGrabber.grabImage()) ! null) { frameCount; String imagePath dir frameCount.jpg; if (frameCount % frameInterval ! 0) continue; BufferedImage bufferedImage converter.getBufferedImage(frame); try (FileOutputStream fileOutputStream new FileOutputStream(imagePath)) { ImageIO.write(bufferedImage, jpg, fileOutputStream); } } logger.info(视频截帧 完成, 视频共 {} 帧, 截帧: {}张, lengthInFrames, frameCount1); } }注意: 在javacv中有 org.opencv.videoio.VideoCapture 也可视频截帧, 但在centos环境open video file为false, 无法运行, 即使安装opencv关联ffmpeg也不行, 暂时无法使用, 大佬们如果可以解决敬请留言!//centos 不可用 VideoCapture videoCapture new VideoCapture(); boolean open videoCapture.open(videoFile);2) 视频跳帧截图此种方式为跳到视频指定帧截图, 适用于要截的帧比较稀疏, 用连续截帧会很慢, 如算法识别到关键帧后, 直接跳到该帧截图/** * ※Desc : 跳帧截图; * ※Date : 2022/4/2 * ※Param : path:视频path; dir:截帧保存文件夹; frameIndexes:需要截帧的FrameNumber */ public void grabFrameJump(String path, String dir, ListInteger frameIndexes) throws Exception { logger.info(视频截帧 sourceFile: {}, path); try (FFmpegFrameGrabber frameGrabber new FFmpegFrameGrabber(path)) { frameGrabber.stop(); frameGrabber.start(); long lengthInTime frameGrabber.getLengthInTime(); logger.info(视频截帧 lengthInTime: {} , lengthInTime); for (Integer frameIndex : frameIndexes) { frameGrabber.setVideoFrameNumber(frameIndex); Frame frame frameGrabber.grabImage(); String imageName frameIndex.jpg; String imagePath dir imageName; BufferedImage bufferedImage converter.getBufferedImage(frame); try (FileOutputStream fileOutputStream new FileOutputStream(imagePath)) { ImageIO.write(bufferedImage, jpg, fileOutputStream); } } frameGrabber.stop(); } logger.info(视频截帧 source sourceFile: {}, path); }其中frameGrabber.setVideoFrameNumber(frameIndex);可以直接跳到指定帧; 有 frameGrabber.setTimestamp 方法跳到指定时间戳, 但现版本会卡死, 大佬们如果可以解决敬请留言!3 音频抽取1) 视频抽取音频/** * ※Desc : 传入视频文件分离出语音文件 * ※Author : zhangsongeastmoney.com * ※Date : 2022/3/8 * ※Param : sourceFile 视频文件(mp4); destDir 转音频后存放文件目录, 文件名为 原文件名 .mp3 * ※Return : */ public static void extractVoice(String sourceFileName, String destFileName) { logger.info(extractVoice source sourceFile: {}, destFileName: {}, sourceFileName, destFileName); //抓取资源 FFmpegFrameGrabber frameGrabber new FFmpegFrameGrabber(sourceFileName); Frame frame null; FFmpegFrameRecorder recorder null; try { frameGrabber.start(); //转录为单轨, 16K采样率, wav格式 recorder new FFmpegFrameRecorder(destFileName, 1);//frameGrabber.getAudioChannels() recorder.setFormat(Constants.AUDIO_FORMAT); recorder.setSampleRate(Constants.AUDIO_SampleRate);//frameGrabber.getSampleRate() //recorder.setAudioBitrate(128000);// 音频比特率 recorder.setTimestamp(frameGrabber.getTimestamp()); logger.info(source video AudioChannels: {}, SampleRate: {}, AudioBitrate: {}, frameGrabber.getAudioChannels(), frameGrabber.getSampleRate(), recorder.getAudioBitrate()); recorder.start(); int index 0; while (true) { frame frameGrabber.grabSamples(); if (frame null) break; if (frame.samples ! null) { recorder.recordSamples(frame.sampleRate, frame.audioChannels, frame.samples); recorder.setTimestamp(frameGrabber.getTimestamp()); } index; } recorder.stop(); recorder.release(); frameGrabber.stop(); logger.info(extractVoice 完成 index index); } catch (Exception e) { e.printStackTrace(); } }注: 只要抓取音频用 frameGrabber.grabSamples(); 用 frameGrabber.grab() 含有图片等信息会慢很多.2) 音频截段如下方法为将一段音频按长度截为多段, 需要截取指定时间段音频也可参考此方法/** * ※Desc : 对给定的音频文件截取, 输出到destDir * ※Author : zhangsongeastmoney.com * ※Date : 2022/3/8 * ※Param : sourceFileName: 源音频文件; audioSplitLength: 多长时间截一段 */ public static ListAudioPartInfo splitAudio(String sourceFileName, String destDir, Long audioSplitLength) { FFmpegFrameGrabber frameGrabber null; ListAudioPartInfo list new ArrayList(); try { FileUtils.forceMkdir(new File(destDir)); logger.info(splitAudio source sourceFile: {}, destDir: {}, sourceFileName, destDir); // 创建文件抓取器, 使用javacv的FFmpeg的相关工具包 frameGrabber new FFmpegFrameGrabber(sourceFileName); //frameGrabber.setOption(RW_TIMEOUT, 20000000); Frame audioSamples null; // 默认音频是pcm采样数据 // 输出文件 if (start(frameGrabber)) { // 时间长度,微秒 long lengthInTimeMs frameGrabber.getLengthInTime(); long part lengthInTimeMs / audioSplitLength 1; logger.info(lengthInTimeMs: {}, splitAudio part: {}, lengthInTimeMs, part); int partIndex -1; FFmpegFrameRecorder recorder null; AudioPartInfo audioPartInfo null; while ((audioSamples frameGrabber.grabSamples()) ! null) { long timestamp frameGrabber.getTimestamp(); if (timestamp (partIndex1) * Constants.AUDIO_SPLIT_LENGTH) { if (recorder ! null) stop(recorder); partIndex; //logger.info(开始截取第{}段音频, start timestamp: {}, partIndex, timestamp); String audioPath destDir partIndex Constants.AUDIO_SUFFIX; recorder new FFmpegFrameRecorder(audioPath , frameGrabber.getAudioChannels()); // 编码格式 recorder.setFormat(Constants.AUDIO_FORMAT); recorder.setAudioCodec(frameGrabber.getAudioCodec()); // 65543 recorder.setAudioBitrate(frameGrabber.getAudioBitrate()); recorder.setSampleRate(frameGrabber.getSampleRate()); recorder.setAudioQuality(0);// 最高质量 recorder.start(); if (audioPartInfo!null) audioPartInfo.setEnd(timestamp / 1000); //上一段语音的结束时间 audioPartInfo new AudioPartInfo(partIndex, audioPath); audioPartInfo.setStart(timestamp / 1000); //μs转为ms list.add(audioPartInfo); } //timestamp 大于 截取起始时间 开始录制 if (recorder ! null) { recorder.setTimestamp(timestamp); recorder.record(audioSamples); audioPartInfo.setEnd(timestamp / 1000); //μs转为ms //这里的timestamp没有包含此次grab的结尾! } } if (recorder ! null) stop(recorder); } } catch (Exception e) { logger.error(, e); } stop(frameGrabber); logger.info(splitAudio audioPartInfoList: {}, JSON.toJSONString(list)); return list; }