hetong007 commented on a change in pull request #11027: Add standard ResNet
data augmentation for ImageRecordIter
URL: https://github.com/apache/incubator-mxnet/pull/11027#discussion_r195586629
##########
File path: src/io/image_aug_default.cc
##########
@@ -218,10 +265,93 @@ class DefaultImageAugmenter : public ImageAugmenter {
res = src;
}
+ if (param_.random_resized_crop) {
+ // random resize crop
+ CHECK(param_.min_random_scale == 1.0f &&
+ param_.max_random_scale == 1.0f &&
+ param_.min_crop_size == -1 &&
+ param_.max_crop_size == -1 &&
+ !param_.rand_crop) <<
+ "\nSetting random_resized_crop to true conflicts with "
+ "min_random_scale, max_random_scale, "
+ "min_crop_size, max_crop_size, "
+ "and rand_crop.";
+ if (param_.max_random_area != 1.0f || param_.min_random_area != 1.0f
+ || param_.max_aspect_ratio != 1.0f || param_.min_aspect_ratio !=
1.0f) {
+ CHECK(param_.min_aspect_ratio > 0.0f);
+ CHECK(param_.min_random_area <= param_.max_random_area);
+ CHECK(param_.min_aspect_ratio <= param_.max_aspect_ratio);
+ std::uniform_real_distribution<float>
rand_uniform_area(param_.min_random_area,
+
param_.max_random_area);
+ std::uniform_real_distribution<float>
rand_uniform_ratio(param_.min_aspect_ratio,
+
param_.max_aspect_ratio);
+ std::uniform_real_distribution<float> rand_uniform(0, 1);
+ float area = res.rows * res.cols;
+ bool attemp = false;
+ for (int i = 0; i < 10; ++i) {
+ float rand_area = rand_uniform_area(*prnd);
+ float ratio = rand_uniform_ratio(*prnd);
+ float target_area = area * rand_area;
+ int y_area = std::round(std::sqrt(target_area / ratio));
+ int x_area = std::round(std::sqrt(target_area * ratio));
+ if (rand_uniform(*prnd) > 0.5) {
+ float temp_y_area = y_area;
+ y_area = x_area;
+ x_area = temp_y_area;
+ }
+ if (y_area <= res.rows && x_area <= res.cols) {
+ // random crop
+ index_t rand_y_area =
+ std::uniform_int_distribution<index_t>(0, res.rows -
y_area)(*prnd);
+ index_t rand_x_area =
+ std::uniform_int_distribution<index_t>(0, res.cols -
x_area)(*prnd);
+ cv::Rect roi(rand_x_area, rand_y_area, x_area, y_area);
+ int interpolation_method = GetInterMethod(param_.inter_method,
x_area, y_area,
+ param_.data_shape[2],
+
param_.data_shape[1], prnd);
+ cv::resize(res(roi), res, cv::Size(param_.data_shape[2],
param_.data_shape[1]),
+ 0, 0, interpolation_method);
+ attemp = true;
+ break;
+ }
+ }
+ if (!attemp) {
+ // center crop
+ int interpolation_method = GetInterMethod(param_.inter_method,
res.cols, res.rows,
+ param_.data_shape[2],
+ param_.data_shape[1],
prnd);
+ if (res.rows < param_.data_shape[1]) {
+ index_t new_cols =
static_cast<index_t>(static_cast<float>(param_.data_shape[1]) /
+
static_cast<float>(res.rows) *
+
static_cast<float>(res.cols));
+ cv::resize(res, res, cv::Size(new_cols, param_.data_shape[1]),
+ 0, 0, interpolation_method);
+ }
+ if (res.cols < param_.data_shape[2]) {
+ index_t new_rows =
static_cast<index_t>(static_cast<float>(param_.data_shape[2]) /
+
static_cast<float>(res.cols) *
+
static_cast<float>(res.rows));
+ cv::resize(res, res, cv::Size(param_.data_shape[2], new_rows),
+ 0, 0, interpolation_method);
+ }
+ CHECK(static_cast<index_t>(res.rows) >= param_.data_shape[1]
+ && static_cast<index_t>(res.cols) >= param_.data_shape[2])
+ << "input image size smaller than input shape";
+ index_t center_y = res.rows - param_.data_shape[1];
+ index_t center_x = res.cols - param_.data_shape[2];
+ center_y /= 2;
+ center_x /= 2;
+ cv::Rect roi(center_x, center_y, param_.data_shape[2],
param_.data_shape[1]);
+ res = res(roi);
+ }
+ random_resized_crop_exec = true;
+ }
+ }
// normal augmentation by affine transformation.
if (param_.max_rotate_angle > 0 || param_.max_shear_ratio > 0.0f
Review comment:
It is possible that users want to add rotation on top of random resized crop.
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