Skip to content
This repository has been archived by the owner on Nov 17, 2023. It is now read-only.

[contrib][op] fix MultiBoxPrior confusing results if first ratio is not 1.0 #13763

Merged
merged 2 commits into from
Apr 18, 2019
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
7 changes: 4 additions & 3 deletions src/operator/contrib/multibox_prior.cc
Original file line number Diff line number Diff line change
Expand Up @@ -44,11 +44,12 @@ inline void MultiBoxPriorForward(const Tensor<cpu, 2, DType> &out,
float center_y = (r + offsets[0]) * step_y;
for (int c = 0; c < in_width; ++c) {
float center_x = (c + offsets[1]) * step_x;
// ratio = 1, various sizes
// ratio = first ratio, various sizes
float ratio = num_ratios > 0? sqrtf(ratios[0]) : 1.f;
for (int i = 0; i < num_sizes; ++i) {
float size = sizes[i];
float w = size * in_height / in_width / 2;
float h = size / 2;
float w = size * in_height / in_width * ratio / 2;
float h = size / ratio / 2;
out[count][0] = center_x - w; // xmin
out[count][1] = center_y - h; // ymin
out[count][2] = center_x + w; // xmax
Expand Down
5 changes: 3 additions & 2 deletions src/operator/contrib/multibox_prior.cu
Original file line number Diff line number Diff line change
Expand Up @@ -83,10 +83,11 @@ inline void MultiBoxPriorForward(const Tensor<gpu, 2, DType> &out,

const int stride = 4 * (num_sizes + num_ratios - 1);
int offset = 0;
// ratio = 1, various sizes
// ratio = first ratio, various sizes
float ratio = num_ratios > 0? sqrtf(ratios[0]) : 1.f;
for (int i = 0; i < num_sizes; ++i) {
cuda::AssignPriors<DType><<<dimGrid, dimBlock, 0, stream>>>(out_ptr,
sizes[i], 1.f, in_width, in_height, step_x, step_y, offset_y, offset_x, stride, offset);
sizes[i], ratio, in_width, in_height, step_x, step_y, offset_y, offset_x, stride, offset);
++offset;
}
MULTIBOXPRIOR_CUDA_CHECK(cudaPeekAtLastError());
Expand Down
14 changes: 13 additions & 1 deletion tests/python/unittest/test_contrib_operator.py
Original file line number Diff line number Diff line change
Expand Up @@ -293,7 +293,7 @@ def f(x, a, b, c):
b = np.random.random_sample()
c = np.random.random_sample()
m = np.random.random_sample() - 0.5

data = mx.symbol.Variable('data')
quad_sym = mx.sym.contrib.quadratic(data=data, a=a, b=b, c=c)
gr_q_sym = mx.sym.contrib.gradientmultiplier(quad_sym, scalar=m)
Expand All @@ -320,6 +320,18 @@ def f(x, a, b, c):
[backward_expected],
rtol=1e-2 if dtype is np.float16 else 1e-5,
atol=1e-2 if dtype is np.float16 else 1e-5)
def test_multibox_prior_op():
h = 561
w = 728
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Is it possible to not hardcode the test values?

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

the input shape is designed specifically for the network

X = mx.nd.random.uniform(shape=(1, 3, h, w))
Y = mx.contrib.nd.MultiBoxPrior(X, sizes=[0.75, 0.5, 0.25], ratios=[1, 2, 0.5])
assert_array_equal(Y.shape, np.array((1, 2042040, 4)))
boxes = Y.reshape((h, w, 5, 4))
assert_allclose(boxes.asnumpy()[250, 250, 0, :], np.array([0.055117, 0.071524, 0.63307 , 0.821524]), atol=1e-5, rtol=1e-5)
# relax first ratio if user insists
Y = mx.contrib.nd.MultiBoxPrior(X, sizes=[0.75, 0.5, 0.25], ratios=[20, 2, 0.5])
boxes = Y.reshape((h, w, 5, 4))
assert_allclose(boxes.asnumpy()[250, 250, 0, :], np.array([-0.948249, 0.362671, 1.636436, 0.530377]), atol=1e-5, rtol=1e-5)

if __name__ == '__main__':
import nose
Expand Down