private Size getOptimalPreviewSize(List<Size> sizes, int w, int h) {
final double ASPECT_TOLERANCE = 0.05;
double targetRatio = (double) w / h;
if (sizes == null) return null;
Size optimalSize = null;
double minDiff = Double.MAX_VALUE;
int targetHeight = h;
// Try to find an size match aspect ratio and size
for (Size size : sizes) {
double ratio = (double) size.width / size.height;
if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE) continue;
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
// Cannot find the one match the aspect ratio, ignore the requirement
if (optimalSize == null) {
minDiff = Double.MAX_VALUE;
for (Size size : sizes) {
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
}
return optimalSize;
}
public static void main(String[] args) {
Mat pFrame = imread("image0.png", CV_LOAD_IMAGE_GRAYSCALE);
Mat cFrame = imread("image1.png", CV_LOAD_IMAGE_GRAYSCALE);
Mat pGray = new Mat();
Mat cGray = new Mat();
pFrame.convertTo(pGray, CV_32FC1);
cFrame.convertTo(cGray, CV_32FC1);
Mat Optical_Flow = new Mat();
DenseOpticalFlow tvl1 = createOptFlow_DualTVL1();
tvl1.calc(pGray, cGray, Optical_Flow);
Mat OF = new Mat(pGray.rows(), pGray.cols(), CV_32FC1);
FloatBuffer in = Optical_Flow.getFloatBuffer();
FloatBuffer out = OF.getFloatBuffer();
int height = pGray.rows();
int width = pGray.cols();
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
float xVelocity = in.get();
float yVelocity = in.get();
float pixelVelocity = (float) Math.sqrt(xVelocity * xVelocity + yVelocity * yVelocity);
out.put(pixelVelocity);
}
}
imwrite("OF.png", OF);
}