diff options
| author | Leo Chan <leochanj@live.unc.edu> | 2020-10-22 01:53:21 -0400 |
|---|---|---|
| committer | Joshua Bakita <jbakita@cs.unc.edu> | 2020-10-22 01:56:35 -0400 |
| commit | d17b33131c14864bd1eae275f49a3f148e21cf29 (patch) | |
| tree | 0d8f77922e8d193cb0f6edab83018f057aad64a0 /SD-VBS/common/toolbox/toolbox_basic/affine/grad.m | |
| parent | 601ed25a4c5b66cb75315832c15613a727db2c26 (diff) | |
Squashed commit of the sb-vbs branch.
Includes the SD-VBS benchmarks modified to:
- Use libextra to loop as realtime jobs
- Preallocate memory before starting their main computation
- Accept input via stdin instead of via argc
Does not include the SD-VBS matlab code.
Fixes libextra execution in LITMUS^RT.
Diffstat (limited to 'SD-VBS/common/toolbox/toolbox_basic/affine/grad.m')
| -rwxr-xr-x | SD-VBS/common/toolbox/toolbox_basic/affine/grad.m | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/SD-VBS/common/toolbox/toolbox_basic/affine/grad.m b/SD-VBS/common/toolbox/toolbox_basic/affine/grad.m new file mode 100755 index 0000000..53bab55 --- /dev/null +++ b/SD-VBS/common/toolbox/toolbox_basic/affine/grad.m | |||
| @@ -0,0 +1,24 @@ | |||
| 1 | % gradient of an image | ||
| 2 | % coordinates (r, c) follow matrix convention; | ||
| 3 | % the gaussian is truncated at x = +- tail, and there are samples samples | ||
| 4 | % inbetween, where samples = hsamples * 2 + 1 | ||
| 5 | |||
| 6 | function[gr,gc] = gradient(image, hsamples) | ||
| 7 | |||
| 8 | tail=4; | ||
| 9 | samples = hsamples * 2 + 1; | ||
| 10 | |||
| 11 | x = linspace(-tail, tail, samples); | ||
| 12 | gauss = exp(-x.^2); | ||
| 13 | n = gauss * ones(samples,1); | ||
| 14 | gauss = gauss/n; | ||
| 15 | |||
| 16 | gaussderiv = -x.*gauss; | ||
| 17 | n = -gaussderiv*linspace(1,samples,samples)'; | ||
| 18 | gaussderiv = gaussderiv/n; | ||
| 19 | |||
| 20 | gr = conv2(conv2(image, gaussderiv','valid'), gauss,'valid'); | ||
| 21 | gc = conv2(conv2(image, gaussderiv,'valid'), gauss','valid'); | ||
| 22 | |||
| 23 | %gr = conv2(conv2(image, gaussderiv','same'), gauss,'same'); | ||
| 24 | %gc = conv2(conv2(image, gaussderiv,'same'), gauss','same'); | ||
