| import numpy as np |
| import cv2 |
| from face_detect.core import randomex |
|
|
| def gen_warp_params (w, flip=False, rotation_range=[-10,10], scale_range=[-0.5, 0.5], tx_range=[-0.05, 0.05], ty_range=[-0.05, 0.05], rnd_state=None ): |
| if rnd_state is None: |
| rnd_state = np.random |
|
|
| rw = None |
| if w < 64: |
| rw = w |
| w = 64 |
| |
| rotation = rnd_state.uniform( rotation_range[0], rotation_range[1] ) |
| scale = rnd_state.uniform(1 +scale_range[0], 1 +scale_range[1]) |
| tx = rnd_state.uniform( tx_range[0], tx_range[1] ) |
| ty = rnd_state.uniform( ty_range[0], ty_range[1] ) |
| p_flip = flip and rnd_state.randint(10) < 4 |
|
|
| |
| cell_size = [ w // (2**i) for i in range(1,4) ] [ rnd_state.randint(3) ] |
| cell_count = w // cell_size + 1 |
|
|
| grid_points = np.linspace( 0, w, cell_count) |
| mapx = np.broadcast_to(grid_points, (cell_count, cell_count)).copy() |
| mapy = mapx.T |
|
|
| mapx[1:-1,1:-1] = mapx[1:-1,1:-1] + randomex.random_normal( size=(cell_count-2, cell_count-2) )*(cell_size*0.24) |
| mapy[1:-1,1:-1] = mapy[1:-1,1:-1] + randomex.random_normal( size=(cell_count-2, cell_count-2) )*(cell_size*0.24) |
|
|
| half_cell_size = cell_size // 2 |
|
|
| mapx = cv2.resize(mapx, (w+cell_size,)*2 )[half_cell_size:-half_cell_size,half_cell_size:-half_cell_size].astype(np.float32) |
| mapy = cv2.resize(mapy, (w+cell_size,)*2 )[half_cell_size:-half_cell_size,half_cell_size:-half_cell_size].astype(np.float32) |
|
|
| |
| random_transform_mat = cv2.getRotationMatrix2D((w // 2, w // 2), rotation, scale) |
| random_transform_mat[:, 2] += (tx*w, ty*w) |
|
|
| params = dict() |
| params['mapx'] = mapx |
| params['mapy'] = mapy |
| params['rmat'] = random_transform_mat |
| u_mat = random_transform_mat.copy() |
| u_mat[:,2] /= w |
| params['umat'] = u_mat |
| params['w'] = w |
| params['rw'] = rw |
| params['flip'] = p_flip |
|
|
| return params |
|
|
| def warp_by_params (params, img, can_warp, can_transform, can_flip, border_replicate, cv2_inter=cv2.INTER_CUBIC): |
| rw = params['rw'] |
| |
| if (can_warp or can_transform) and rw is not None: |
| img = cv2.resize(img, (64,64), interpolation=cv2_inter) |
| |
| if can_warp: |
| img = cv2.remap(img, params['mapx'], params['mapy'], cv2_inter ) |
| if can_transform: |
| img = cv2.warpAffine( img, params['rmat'], (params['w'], params['w']), borderMode=(cv2.BORDER_REPLICATE if border_replicate else cv2.BORDER_CONSTANT), flags=cv2_inter ) |
| |
| |
| if (can_warp or can_transform) and rw is not None: |
| img = cv2.resize(img, (rw,rw), interpolation=cv2_inter) |
| |
| if len(img.shape) == 2: |
| img = img[...,None] |
| if can_flip and params['flip']: |
| img = img[:,::-1,...] |
| return img |
