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 | 1 | initial version |
The question that arises immediately is: wouldn't the operation of cropping the image compensate the time needed to compute the rest of the 640x640 - 100x100 pixels ?
no, cropping is almost for free, an operation like:
cv:: Mat cropped = image(cv::Rect(10,10,100,100));
does not copy any memory, it returns a new Mat header with updated sizes, while the data points to the original memory (with some offset)
( same for numpy "slices" like `image[10:110, 10:110] )
| | 2 | No.2 Revision |
The question that arises immediately is: wouldn't the operation of cropping the image compensate the time needed to compute the rest of the 640x640 - 100x100 pixels ?
no, cropping is almost for free, an operation like:
cv:: Mat cropped = image(cv::Rect(10,10,100,100));
does not copy any memory, it returns a new Mat header with updated sizes, while the data points to the original memory (with some offset)
( same for numpy "slices" like `image[10:110, 10:110] image[10:110, 10:110] )
