在camera2上裁剪矩形子部分并将其传递给opencv进行处理
问题描述:
我设法绘制了一个覆盖矩形,以便矩形内部是唯一要处理的部分,应用程序应该忽略相机区域的其余部分。 link to Screenshot在camera2上裁剪矩形子部分并将其传递给opencv进行处理
的问题是我要裁剪上onimagaavailable功能上面的矩形,如下图所示:
@Override
public void onImageAvailable(ImageReader reader) {
Image img = reader.acquireLatestImage();
//THIS IS WHERE I WANT TO CROP THE IMAGE TO ONLY SHOW WHAT WAS IN THE
// ABOVE DRAWN RECTANGLE BUT I DONT KNOW HOW, I HAVE GOOGLED FOR THE
// PAST WEEK ON THIS
//after processing i should pass the image to my opencv processing
//algorithm
process(img)
}
这是我绘制矩形覆盖上camera2的顶部
@Override
protected void onDraw(Canvas canvas) { // Override the onDraw() Method
super.onDraw(canvas);
paint.setStyle(Paint.Style.STROKE);
paint.setColor(Color.WHITE);
paint.setStrokeWidth(10);
int width = canvas.getWidth()/2;
int height = canvas.getHeight()/4;
int height1 = canvas.getHeight()/3;
int height_1 = canvas.getHeight()/10;
int fin = canvas.getWidth() + canvas.getWidth()/3;
int top = height/4;
Log.e("top", top + "");
canvas.drawRect(canvas.getWidth() - (canvas.getWidth() - 150),
canvas.getHeight() - fin, canvas.getWidth() - 150, height + top, paint);
}
请码帮助/告诉我可以使用哪个代码从ImageReader图像裁剪矩形,以便我可以将裁剪后的图像传递给我的处理算法
答
在onImageAvailable(),您可以使用 Bitmap.createBitmap如果是JPEG格式,你转换为位图
Rect rectCrop = new Rect(left,top,right,bottom);
Bitmap bitmapRotated = Bitmap.createBitmap(bitmap, rectCrop.left, rectCrop.top, rectCrop.width(), rectCrop.height(), mat, true);
如果使用YUV可以减少存储和使用compressToJpeg与矩形,它更轻过程
yuv.compressToJpeg(rect, compress, out);
请注意,您可以使用OpenCV相机,并在'onCameraFrame()'中裁剪预览图像,以便相同的子Mat进行显示和图像处理。请参阅https://stackoverflow.com/a/47519725/192373 –