From b12a85913a067b08bdcd633a40cf7e3529faec4d Mon Sep 17 00:00:00 2001
From: Giovanni Cavallin <37183651+mawanda-jun@users.noreply.github.com>
Date: Mon, 30 Sep 2024 12:04:37 +0200
Subject: [PATCH] Enable float32 image dtype in (Cached)MixUp

The old method was forcing the `np.uint8` dtype on the output image, thus not permitting the float32 dtype (case of images in (0, 1) interval).
---
 mmdet/datasets/transforms/transforms.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/mmdet/datasets/transforms/transforms.py b/mmdet/datasets/transforms/transforms.py
index c50b987db33..acc8bd32583 100644
--- a/mmdet/datasets/transforms/transforms.py
+++ b/mmdet/datasets/transforms/transforms.py
@@ -2668,7 +2668,7 @@ def transform(self, results: dict) -> dict:
         target_h, target_w = ori_img.shape[:2]
         padded_img = np.ones((max(origin_h, target_h), max(
             origin_w, target_w), 3)) * self.pad_val
-        padded_img = padded_img.astype(np.uint8)
+        padded_img = padded_img.astype(retrieve_img.dtype)
         padded_img[:origin_h, :origin_w] = out_img
 
         x_offset, y_offset = 0, 0
@@ -2715,7 +2715,7 @@ def transform(self, results: dict) -> dict:
         mixup_gt_bboxes_labels = mixup_gt_bboxes_labels[inside_inds]
         mixup_gt_ignore_flags = mixup_gt_ignore_flags[inside_inds]
 
-        results['img'] = mixup_img.astype(np.uint8)
+        results['img'] = mixup_img.astype(retrieve_img.dtype)
         results['img_shape'] = mixup_img.shape[:2]
         results['gt_bboxes'] = mixup_gt_bboxes
         results['gt_bboxes_labels'] = mixup_gt_bboxes_labels
@@ -3765,7 +3765,7 @@ def transform(self, results: dict) -> dict:
         target_h, target_w = ori_img.shape[:2]
         padded_img = np.ones((max(origin_h, target_h), max(
             origin_w, target_w), 3)) * self.pad_val
-        padded_img = padded_img.astype(np.uint8)
+        padded_img = padded_img.astype(retrieve_img.dtype)
         padded_img[:origin_h, :origin_w] = out_img
 
         x_offset, y_offset = 0, 0
@@ -3833,7 +3833,7 @@ def transform(self, results: dict) -> dict:
         if with_mask:
             mixup_gt_masks = mixup_gt_masks[inside_inds]
 
-        results['img'] = mixup_img.astype(np.uint8)
+        results['img'] = mixup_img.astype(retrieve_img.dtype)
         results['img_shape'] = mixup_img.shape[:2]
         results['gt_bboxes'] = mixup_gt_bboxes
         results['gt_bboxes_labels'] = mixup_gt_bboxes_labels