我在使用Android OpenCV二进制文件裁剪图像时遇到问题。

这是我要尝试裁剪图像左上象限的操作:

Initialization {
    mYuv = new Mat(mFrameSize.height + mFrameSize.height / 2, mFrameSize.width, CvType.CV_8UC1);
    mGraySubmat = mYuv.submat(0, mFrameSize.height, 0, mFrameSize.width);
}


processFrame(byte[] data) {
   mYuv.put(0, 0, data);
   Imgproc.cvtColor(mGraySubmat, mRgba, Imgproc.COLOR_GRAY2BGR, 4);
   bmp = Bitmap.createBitmap(mFrameSize.width/2, mFrameSize.height/2, Bitmap.Config.ARGB_8888);
   Rect roi = new Rect(0,0,mFrameSize.width/2,mFrameSize.height/2);
   Mat faceMat = new Mat(mRgba,roi);
   Utils.matToBitmap(faceMat.clone(), bmp);       

processFrame(byte[] data) {

     for (int i = 0; i < frameSize; i++) {
     int y = (0xff & ((int) data[i]));
     rgba[i] = 0xff000000 + (y << 16) + (y << 8) + y;
}
// Example of cropping the upper left corder
bmp = Bitmap.createBitmap(mFrameSize.width/2, mFrameSize.height/2, Bitmap.Config.RGB_565);
bmp.setPixels(rgba, 0/* offset */, mFrameSize.width /* stride */, 0, 0, mFrameSize.width/2, mFrameSize.height/2);

最佳答案

我猜你是从this example开始的。在此原始资源中，您可以看到没有Imgproc.COLOR_GRAY2BGR转换。如果要获得彩色图像，则需要使用选择二:

Imgproc.cvtColor(mYuv, mRgba, Imgproc.COLOR_YUV420sp2RGB, 4);

Imgproc.cvtColor(mGraySubmat, mRgba, Imgproc.COLOR_GRAY2RGBA, 4);

https://stackoverflow.com/questions/9469730/