RandomFlip

class mmocr.datasets.transforms.RandomFlip(prob=None, direction='horizontal', swap_seg_labels=None)

Flip the image & bbox polygon.

There are 3 flip modes:

• prob is float, direction is string: the image will be

  direction``ly flipped with probability of ``prob . E.g., prob=0.5, direction='horizontal', then image will be horizontally flipped with probability of 0.5.

• prob is float, direction is list of string: the image will

  be direction[i]``ly flipped with probability of ``prob/len(direction). E.g., prob=0.5, direction=['horizontal', 'vertical'], then image will be horizontally flipped with probability of 0.25, vertically with probability of 0.25.

• prob is list of float, direction is list of string:

  given len(prob) == len(direction), the image will be direction[i]``ly flipped with probability of ``prob[i]. E.g., prob=[0.3, 0.5], direction=['horizontal', 'vertical'], then image will be horizontally flipped with probability of 0.3, vertically with probability of 0.5.

Required Keys:

• img

• gt_bboxes (optional)

• gt_polygons (optional)

Modified Keys:

• img

• gt_bboxes (optional)

• gt_polygons (optional)

Added Keys:

• flip

• flip_direction

参数

• prob (float | list[float], optional) – The flipping probability. Defaults to None.

• direction (str | list[str]) – The flipping direction. Options If input is a list, the length must equal prob. Each element in prob indicates the flip probability of corresponding direction. Defaults to ‘horizontal’.

• swap_seg_labels (Optional[Sequence]) –

返回类型

None

flip_polygons(polygons, img_shape, direction)

Flip polygons horizontally, vertically or diagonally.

参数

• polygons (list[numpy.ndarray) – polygons.

• img_shape (tuple[int]) – Image shape (height, width)

• direction (str) – Flip direction. Options are ‘horizontal’, ‘vertical’ and ‘diagonal’.

返回

Flipped polygons.

返回类型

list[numpy.ndarray]