From 495ffc4777522e40941753e3b1b79c02f84b25b4 Mon Sep 17 00:00:00 2001 From: Grafting Rayman <156515434+GraftingRayman@users.noreply.github.com> Date: Fri, 17 Jan 2025 11:00:30 +0000 Subject: Add files via upload --- r_basicsr/utils/img_util.py | 172 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 172 insertions(+) create mode 100644 r_basicsr/utils/img_util.py (limited to 'r_basicsr/utils/img_util.py') diff --git a/r_basicsr/utils/img_util.py b/r_basicsr/utils/img_util.py new file mode 100644 index 0000000..3ad2be2 --- /dev/null +++ b/r_basicsr/utils/img_util.py @@ -0,0 +1,172 @@ +import cv2 +import math +import numpy as np +import os +import torch +from torchvision.utils import make_grid + + +def img2tensor(imgs, bgr2rgb=True, float32=True): + """Numpy array to tensor. + + Args: + imgs (list[ndarray] | ndarray): Input images. + bgr2rgb (bool): Whether to change bgr to rgb. + float32 (bool): Whether to change to float32. + + Returns: + list[tensor] | tensor: Tensor images. If returned results only have + one element, just return tensor. + """ + + def _totensor(img, bgr2rgb, float32): + if img.shape[2] == 3 and bgr2rgb: + if img.dtype == 'float64': + img = img.astype('float32') + img = cv2.cvtColor(img, cv2.COLOR_BGR2RGB) + img = torch.from_numpy(img.transpose(2, 0, 1)) + if float32: + img = img.float() + return img + + if isinstance(imgs, list): + return [_totensor(img, bgr2rgb, float32) for img in imgs] + else: + return _totensor(imgs, bgr2rgb, float32) + + +def tensor2img(tensor, rgb2bgr=True, out_type=np.uint8, min_max=(0, 1)): + """Convert torch Tensors into image numpy arrays. + + After clamping to [min, max], values will be normalized to [0, 1]. + + Args: + tensor (Tensor or list[Tensor]): Accept shapes: + 1) 4D mini-batch Tensor of shape (B x 3/1 x H x W); + 2) 3D Tensor of shape (3/1 x H x W); + 3) 2D Tensor of shape (H x W). + Tensor channel should be in RGB order. + rgb2bgr (bool): Whether to change rgb to bgr. + out_type (numpy type): output types. If ``np.uint8``, transform outputs + to uint8 type with range [0, 255]; otherwise, float type with + range [0, 1]. Default: ``np.uint8``. + min_max (tuple[int]): min and max values for clamp. + + Returns: + (Tensor or list): 3D ndarray of shape (H x W x C) OR 2D ndarray of + shape (H x W). The channel order is BGR. + """ + if not (torch.is_tensor(tensor) or (isinstance(tensor, list) and all(torch.is_tensor(t) for t in tensor))): + raise TypeError(f'tensor or list of tensors expected, got {type(tensor)}') + + if torch.is_tensor(tensor): + tensor = [tensor] + result = [] + for _tensor in tensor: + _tensor = _tensor.squeeze(0).float().detach().cpu().clamp_(*min_max) + _tensor = (_tensor - min_max[0]) / (min_max[1] - min_max[0]) + + n_dim = _tensor.dim() + if n_dim == 4: + img_np = make_grid(_tensor, nrow=int(math.sqrt(_tensor.size(0))), normalize=False).numpy() + img_np = img_np.transpose(1, 2, 0) + if rgb2bgr: + img_np = cv2.cvtColor(img_np, cv2.COLOR_RGB2BGR) + elif n_dim == 3: + img_np = _tensor.numpy() + img_np = img_np.transpose(1, 2, 0) + if img_np.shape[2] == 1: # gray image + img_np = np.squeeze(img_np, axis=2) + else: + if rgb2bgr: + img_np = cv2.cvtColor(img_np, cv2.COLOR_RGB2BGR) + elif n_dim == 2: + img_np = _tensor.numpy() + else: + raise TypeError(f'Only support 4D, 3D or 2D tensor. But received with dimension: {n_dim}') + if out_type == np.uint8: + # Unlike MATLAB, numpy.unit8() WILL NOT round by default. + img_np = (img_np * 255.0).round() + img_np = img_np.astype(out_type) + result.append(img_np) + if len(result) == 1: + result = result[0] + return result + + +def tensor2img_fast(tensor, rgb2bgr=True, min_max=(0, 1)): + """This implementation is slightly faster than tensor2img. + It now only supports torch tensor with shape (1, c, h, w). + + Args: + tensor (Tensor): Now only support torch tensor with (1, c, h, w). + rgb2bgr (bool): Whether to change rgb to bgr. Default: True. + min_max (tuple[int]): min and max values for clamp. + """ + output = tensor.squeeze(0).detach().clamp_(*min_max).permute(1, 2, 0) + output = (output - min_max[0]) / (min_max[1] - min_max[0]) * 255 + output = output.type(torch.uint8).cpu().numpy() + if rgb2bgr: + output = cv2.cvtColor(output, cv2.COLOR_RGB2BGR) + return output + + +def imfrombytes(content, flag='color', float32=False): + """Read an image from bytes. + + Args: + content (bytes): Image bytes got from files or other streams. + flag (str): Flags specifying the color type of a loaded image, + candidates are `color`, `grayscale` and `unchanged`. + float32 (bool): Whether to change to float32., If True, will also norm + to [0, 1]. Default: False. + + Returns: + ndarray: Loaded image array. + """ + img_np = np.frombuffer(content, np.uint8) + imread_flags = {'color': cv2.IMREAD_COLOR, 'grayscale': cv2.IMREAD_GRAYSCALE, 'unchanged': cv2.IMREAD_UNCHANGED} + img = cv2.imdecode(img_np, imread_flags[flag]) + if float32: + img = img.astype(np.float32) / 255. + return img + + +def imwrite(img, file_path, params=None, auto_mkdir=True): + """Write image to file. + + Args: + img (ndarray): Image array to be written. + file_path (str): Image file path. + params (None or list): Same as opencv's :func:`imwrite` interface. + auto_mkdir (bool): If the parent folder of `file_path` does not exist, + whether to create it automatically. + + Returns: + bool: Successful or not. + """ + if auto_mkdir: + dir_name = os.path.abspath(os.path.dirname(file_path)) + os.makedirs(dir_name, exist_ok=True) + ok = cv2.imwrite(file_path, img, params) + if not ok: + raise IOError('Failed in writing images.') + + +def crop_border(imgs, crop_border): + """Crop borders of images. + + Args: + imgs (list[ndarray] | ndarray): Images with shape (h, w, c). + crop_border (int): Crop border for each end of height and weight. + + Returns: + list[ndarray]: Cropped images. + """ + if crop_border == 0: + return imgs + else: + if isinstance(imgs, list): + return [v[crop_border:-crop_border, crop_border:-crop_border, ...] for v in imgs] + else: + return imgs[crop_border:-crop_border, crop_border:-crop_border, ...] -- cgit v1.2.3