# -*- coding: utf-8 -*- """ Created on Mon Apr 24 15:43:29 2017 @author: zhaoy """ """ @Modified by yangxy (yangtao9009@gmail.com) """ import cv2 import numpy as np from skimage import transform as trans # reference facial points, a list of coordinates (x,y) REFERENCE_FACIAL_POINTS = [ [30.29459953, 51.69630051], [65.53179932, 51.50139999], [48.02519989, 71.73660278], [33.54930115, 92.3655014], [62.72990036, 92.20410156] ] DEFAULT_CROP_SIZE = (96, 112) def _umeyama(src, dst, estimate_scale=True, scale=1.0): """Estimate N-D similarity transformation with or without scaling. Parameters ---------- src : (M, N) array Source coordinates. dst : (M, N) array Destination coordinates. estimate_scale : bool Whether to estimate scaling factor. Returns ------- T : (N + 1, N + 1) The homogeneous similarity transformation matrix. The matrix contains NaN values only if the problem is not well-conditioned. References ---------- .. [1] "Least-squares estimation of transformation parameters between two point patterns", Shinji Umeyama, PAMI 1991, :DOI:`10.1109/34.88573` """ num = src.shape[0] dim = src.shape[1] # Compute mean of src and dst. src_mean = src.mean(axis=0) dst_mean = dst.mean(axis=0) # Subtract mean from src and dst. src_demean = src - src_mean dst_demean = dst - dst_mean # Eq. (38). A = dst_demean.T @ src_demean / num # Eq. (39). d = np.ones((dim,), dtype=np.double) if np.linalg.det(A) < 0: d[dim - 1] = -1 T = np.eye(dim + 1, dtype=np.double) U, S, V = np.linalg.svd(A) # Eq. (40) and (43). rank = np.linalg.matrix_rank(A) if rank == 0: return np.nan * T elif rank == dim - 1: if np.linalg.det(U) * np.linalg.det(V) > 0: T[:dim, :dim] = U @ V else: s = d[dim - 1] d[dim - 1] = -1 T[:dim, :dim] = U @ np.diag(d) @ V d[dim - 1] = s else: T[:dim, :dim] = U @ np.diag(d) @ V if estimate_scale: # Eq. (41) and (42). scale = 1.0 / src_demean.var(axis=0).sum() * (S @ d) else: scale = scale T[:dim, dim] = dst_mean - scale * (T[:dim, :dim] @ src_mean.T) T[:dim, :dim] *= scale return T, scale class FaceWarpException(Exception): def __str__(self): return 'In File {}:{}'.format( __file__, super.__str__(self)) def get_reference_facial_points(output_size=None, inner_padding_factor=0.0, outer_padding=(0, 0), default_square=False): tmp_5pts = np.array(REFERENCE_FACIAL_POINTS) tmp_crop_size = np.array(DEFAULT_CROP_SIZE) # 0) make the inner region a square if default_square: size_diff = max(tmp_crop_size) - tmp_crop_size tmp_5pts += size_diff / 2 tmp_crop_size += size_diff if (output_size and output_size[0] == tmp_crop_size[0] and output_size[1] == tmp_crop_size[1]): print('output_size == DEFAULT_CROP_SIZE {}: return default reference points'.format(tmp_crop_size)) return tmp_5pts if (inner_padding_factor == 0 and outer_padding == (0, 0)): if output_size is None: print('No paddings to do: return default reference points') return tmp_5pts else: raise FaceWarpException( 'No paddings to do, output_size must be None or {}'.format(tmp_crop_size)) # check output size if not (0 <= inner_padding_factor <= 1.0): raise FaceWarpException('Not (0 <= inner_padding_factor <= 1.0)') if ((inner_padding_factor > 0 or outer_padding[0] > 0 or outer_padding[1] > 0) and output_size is None): output_size = tmp_crop_size * \ (1 + inner_padding_factor * 2).astype(np.int32) output_size += np.array(outer_padding) print(' deduced from paddings, output_size = ', output_size) if not (outer_padding[0] < output_size[0] and outer_padding[1] < output_size[1]): raise FaceWarpException('Not (outer_padding[0] < output_size[0]' 'and outer_padding[1] < output_size[1])') # 1) pad the inner region according inner_padding_factor # print('---> STEP1: pad the inner region according inner_padding_factor') if inner_padding_factor > 0: size_diff = tmp_crop_size * inner_padding_factor * 2 tmp_5pts += size_diff / 2 tmp_crop_size += np.round(size_diff).astype(np.int32) # print(' crop_size = ', tmp_crop_size) # print(' reference_5pts = ', tmp_5pts) # 2) resize the padded inner region # print('---> STEP2: resize the padded inner region') size_bf_outer_pad = np.array(output_size) - np.array(outer_padding) * 2 # print(' crop_size = ', tmp_crop_size) # print(' size_bf_outer_pad = ', size_bf_outer_pad) if size_bf_outer_pad[0] * tmp_crop_size[1] != size_bf_outer_pad[1] * tmp_crop_size[0]: raise FaceWarpException('Must have (output_size - outer_padding)' '= some_scale * (crop_size * (1.0 + inner_padding_factor)') scale_factor = size_bf_outer_pad[0].astype(np.float32) / tmp_crop_size[0] # print(' resize scale_factor = ', scale_factor) tmp_5pts = tmp_5pts * scale_factor # size_diff = tmp_crop_size * (scale_factor - min(scale_factor)) # tmp_5pts = tmp_5pts + size_diff / 2 tmp_crop_size = size_bf_outer_pad # print(' crop_size = ', tmp_crop_size) # print(' reference_5pts = ', tmp_5pts) # 3) add outer_padding to make output_size reference_5point = tmp_5pts + np.array(outer_padding) tmp_crop_size = output_size # print('---> STEP3: add outer_padding to make output_size') # print(' crop_size = ', tmp_crop_size) # print(' reference_5pts = ', tmp_5pts) # # print('===> end get_reference_facial_points\n') return reference_5point def get_affine_transform_matrix(src_pts, dst_pts): tfm = np.float32([[1, 0, 0], [0, 1, 0]]) n_pts = src_pts.shape[0] ones = np.ones((n_pts, 1), src_pts.dtype) src_pts_ = np.hstack([src_pts, ones]) dst_pts_ = np.hstack([dst_pts, ones]) A, res, rank, s = np.linalg.lstsq(src_pts_, dst_pts_) if rank == 3: tfm = np.float32([ [A[0, 0], A[1, 0], A[2, 0]], [A[0, 1], A[1, 1], A[2, 1]] ]) elif rank == 2: tfm = np.float32([ [A[0, 0], A[1, 0], 0], [A[0, 1], A[1, 1], 0] ]) return tfm def warp_and_crop_face(src_img, facial_pts, reference_pts=None, crop_size=(96, 112), align_type='smilarity'): #smilarity cv2_affine affine if reference_pts is None: if crop_size[0] == 96 and crop_size[1] == 112: reference_pts = REFERENCE_FACIAL_POINTS else: default_square = False inner_padding_factor = 0 outer_padding = (0, 0) output_size = crop_size reference_pts = get_reference_facial_points(output_size, inner_padding_factor, outer_padding, default_square) ref_pts = np.float32(reference_pts) ref_pts_shp = ref_pts.shape if max(ref_pts_shp) < 3 or min(ref_pts_shp) != 2: raise FaceWarpException( 'reference_pts.shape must be (K,2) or (2,K) and K>2') if ref_pts_shp[0] == 2: ref_pts = ref_pts.T src_pts = np.float32(facial_pts) src_pts_shp = src_pts.shape if max(src_pts_shp) < 3 or min(src_pts_shp) != 2: raise FaceWarpException( 'facial_pts.shape must be (K,2) or (2,K) and K>2') if src_pts_shp[0] == 2: src_pts = src_pts.T if src_pts.shape != ref_pts.shape: raise FaceWarpException( 'facial_pts and reference_pts must have the same shape') if align_type is 'cv2_affine': tfm = cv2.getAffineTransform(src_pts[0:3], ref_pts[0:3]) tfm_inv = cv2.getAffineTransform(ref_pts[0:3], src_pts[0:3]) elif align_type is 'affine': tfm = get_affine_transform_matrix(src_pts, ref_pts) tfm_inv = get_affine_transform_matrix(ref_pts, src_pts) else: params, scale = _umeyama(src_pts, ref_pts) tfm = params[:2, :] params, _ = _umeyama(ref_pts, src_pts, False, scale=1.0/scale) tfm_inv = params[:2, :] face_img = cv2.warpAffine(src_img, tfm, (crop_size[0], crop_size[1]), flags=3) return face_img, tfm_inv