ADD the algorithms of image augmentation (#5792)

* ADD the algorithms of image augmentation

* ADD the algorithms of image augmentation

* ADD the algorithms of image augmentation

* ADD the algorithms of image augmentation

* ADD the algorithms of image augmentation

* ADD the algorithms of image augmentation

* UPDATE format code

* UPDATE format and recode structure

* UPDATE format import library

* UPDATE code structure

* Fix all checks have failded

* FIX variable format

* FIX variable format

* FIX variable format

* FIX code structure

* FIX code structure

* FIX code structure

* FIX code structure

computer_vision/flip_augmentation.py

@@ -0,0 +1,131 @@
+import glob
+import os
+import random
+from string import ascii_lowercase, digits
+
+import cv2
+
+"""
+Flip image and bounding box for computer vision task
+https://paperswithcode.com/method/randomhorizontalflip
+"""
+
+# Params
+LABEL_DIR = ""
+IMAGE_DIR = ""
+OUTPUT_DIR = ""
+FLIP_TYPE = 1  # (0 is vertical, 1 is horizontal)
+
+
+def main() -> None:
+    """
+    Get images list and annotations list from input dir.
+    Update new images and annotations.
+    Save images and annotations in output dir.
+    >>> pass  # A doctest is not possible for this function.
+    """
+    img_paths, annos = get_dataset(LABEL_DIR, IMAGE_DIR)
+    print("Processing...")
+    new_images, new_annos, paths = update_image_and_anno(img_paths, annos, FLIP_TYPE)
+
+    for index, image in enumerate(new_images):
+        # Get random string code: '7b7ad245cdff75241935e4dd860f3bad'
+        letter_code = random_chars(32)
+        file_name = paths[index].split(os.sep)[-1].rsplit(".", 1)[0]
+        file_root = f"{OUTPUT_DIR}/{file_name}_FLIP_{letter_code}"
+        cv2.imwrite(f"/{file_root}.jpg", image, [cv2.IMWRITE_JPEG_QUALITY, 85])
+        print(f"Success {index+1}/{len(new_images)} with {file_name}")
+        annos_list = []
+        for anno in new_annos[index]:
+            obj = f"{anno[0]} {anno[1]} {anno[2]} {anno[3]} {anno[4]}"
+            annos_list.append(obj)
+        with open(f"/{file_root}.txt", "w") as outfile:
+            outfile.write("\n".join(line for line in annos_list))
+
+
+def get_dataset(label_dir: str, img_dir: str) -> tuple[list, list]:
+    """
+    - label_dir <type: str>: Path to label include annotation of images
+    - img_dir <type: str>: Path to folder contain images
+    Return <type: list>: List of images path and labels
+    >>> pass  # A doctest is not possible for this function.
+    """
+    img_paths = []
+    labels = []
+    for label_file in glob.glob(os.path.join(label_dir, "*.txt")):
+        label_name = label_file.split(os.sep)[-1].rsplit(".", 1)[0]
+        with open(label_file) as in_file:
+            obj_lists = in_file.readlines()
+        img_path = os.path.join(img_dir, f"{label_name}.jpg")
+
+        boxes = []
+        for obj_list in obj_lists:
+            obj = obj_list.rstrip("\n").split(" ")
+            boxes.append(
+                [
+                    int(obj[0]),
+                    float(obj[1]),
+                    float(obj[2]),
+                    float(obj[3]),
+                    float(obj[4]),
+                ]
+            )
+        if not boxes:
+            continue
+        img_paths.append(img_path)
+        labels.append(boxes)
+    return img_paths, labels
+
+
+def update_image_and_anno(
+    img_list: list, anno_list: list, flip_type: int = 1
+) -> tuple[list, list, list]:
+    """
+    - img_list <type: list>: list of all images
+    - anno_list <type: list>: list of all annotations of specific image
+    - flip_type <type: int>: 0 is vertical, 1 is horizontal
+    Return:
+        - new_imgs_list <type: narray>: image after resize
+        - new_annos_lists <type: list>: list of new annotation after scale
+        - path_list <type: list>: list the name of image file
+    >>> pass  # A doctest is not possible for this function.
+    """
+    new_annos_lists = []
+    path_list = []
+    new_imgs_list = []
+    for idx in range(len(img_list)):
+        new_annos = []
+        path = img_list[idx]
+        path_list.append(path)
+        img_annos = anno_list[idx]
+        img = cv2.imread(path)
+        if flip_type == 1:
+            new_img = cv2.flip(img, flip_type)
+            for bbox in img_annos:
+                x_center_new = 1 - bbox[1]
+                new_annos.append([bbox[0], x_center_new, bbox[2], bbox[3], bbox[4]])
+        elif flip_type == 0:
+            new_img = cv2.flip(img, flip_type)
+            for bbox in img_annos:
+                y_center_new = 1 - bbox[2]
+                new_annos.append([bbox[0], bbox[1], y_center_new, bbox[3], bbox[4]])
+        new_annos_lists.append(new_annos)
+        new_imgs_list.append(new_img)
+    return new_imgs_list, new_annos_lists, path_list
+
+
+def random_chars(number_char: int = 32) -> str:
+    """
+    Automatic generate random 32 characters.
+    Get random string code: '7b7ad245cdff75241935e4dd860f3bad'
+    >>> len(random_chars(32))
+    32
+    """
+    assert number_char > 1, "The number of character should greater than 1"
+    letter_code = ascii_lowercase + digits
+    return "".join(random.choice(letter_code) for _ in range(number_char))
+
+
+if __name__ == "__main__":
+    main()
+    print("DONE ✅")