javacv獲取攝像頭影象
阿新 • • 發佈:2018-12-26
javacv開發包是用於支援java多媒體開發的一套開發包,可以適用於本地多媒體(音視訊)呼叫以及音視訊,圖片等檔案後期操作(圖片修改,音視訊解碼剪輯等等功能)。
這些需要引入的包。音視訊處理使用ffmpeg,影象處理使用opencv,攝像頭抓取使用opencv
1、讀取攝像頭的影象
public class JavavcCameraTest{ public static void main(String[] args) throws Exception, InterruptedException{ OpenCVFrameGrabber grabber = new OpenCVFrameGrabber(0); grabber.start();//開始獲取攝像頭資料 CanvasFrame canvas = new CanvasFrame("攝像頭");//新建一個視窗 canvas.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); canvas.setAlwaysOnTop(true); while(true){ if(!canvas.isDisplayable()){//視窗是否關閉 grabber.stop();//停止抓取 System.exit(2);//退出 break; } canvas.showImage(grabber.grab());//獲取攝像頭影象並放到視窗上顯示, 這裡的Frame frame=grabber.grab(); frame是一幀視訊影象 Thread.sleep(200);//50毫秒重新整理一次影象 } } }
效果:
2、擷取攝像頭都畫面並儲存下來
public class JavavcCameraTest { static OpenCVFrameConverter.ToIplImage converter = newOpenCVFrameConverter.ToIplImage(); public static void main(String[] args) throws Exception, InterruptedException { OpenCVFrameGrabber grabber = new OpenCVFrameGrabber(0); grabber.start(); //開始獲取攝像頭資料 CanvasFrame canvas = new CanvasFrame("攝像頭");//新建一個視窗 canvas.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); canvas.setAlwaysOnTop(true); int ex = 0; while(true) { if(!canvas.isDisplayable()) {//視窗是否關閉 grabber.stop();//停止抓取 System.exit(2);//退出 break; } canvas.showImage(grabber.grab());//獲取攝像頭影象並放到視窗上顯示, 這裡的Frame frame=grabber.grab(); frame是一幀視訊影象 opencv_core.Mat mat = converter.convertToMat(grabber.grabFrame()); ex++; opencv_imgcodecs.imwrite("d:\\img\\" + ex + ".png", mat); Thread.sleep(200);//50毫秒重新整理一次影象 } } }
grabber.grab()和grabber.grabFrame()都可以獲得當時攝像頭的影象,但都是Frame型別的影象,想要儲存需要先呼叫penCVFrameConverter.ToIplImage的convertToMat轉換為mat型別,然後呼叫opencv_imgcodecs.imwrite()方法進行儲存。
效果:
3、擷取視訊的畫面
public abstract class FrameGrabberKit { public static void main(String[] args) throws Exception { String inputFilePth = "C:\\Users\\Administrator\\Desktop\\a.mp4"; randomGrabberFFmpegImage(inputFilePth, 5); } public static void randomGrabberFFmpegImage(String filePath, int randomSize) throws Exception { FFmpegFrameGrabber ff = FFmpegFrameGrabber.createDefault(filePath); ff.start(); int ffLength = ff.getLengthInFrames(); List<Integer> randomGrab = random(ffLength, randomSize); int maxRandomGrab = randomGrab.get(randomGrab.size() - 1); Frame f; int i = 0; while (i < ffLength) { f = ff.grabImage(); if (randomGrab.contains(i)) { doExecuteFrame(f, i); } if (i >= maxRandomGrab) { break; } i++; } ff.stop(); } public static void doExecuteFrame(Frame f, int index) { if (null == f || null == f.image) { return; } OpenCVFrameConverter.ToIplImage converter = new OpenCVFrameConverter.ToIplImage(); String imageMat = "png"; String FileName = "D:\\img"; opencv_core.Mat mat = converter.convertToMat(f); opencv_imgcodecs.imwrite("d:\\img\\" + index + "sls.png", mat);//儲存影象 } public static List<Integer> random(int baseNum, int length) { List<Integer> list = new ArrayList<>(length); while (list.size() < length) { Integer next = (int) (Math.random() * baseNum); if (list.contains(next)) { continue; } list.add(next); } Collections.sort(list); return list; } }
inputFilePth是視訊的路徑。這裡隨機挑了5個畫面的影象儲存下來。
效果: