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/data/degradations.py | 768 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 768 insertions(+) create mode 100644 r_basicsr/data/degradations.py (limited to 'r_basicsr/data/degradations.py') diff --git a/r_basicsr/data/degradations.py b/r_basicsr/data/degradations.py new file mode 100644 index 0000000..c52cd91 --- /dev/null +++ b/r_basicsr/data/degradations.py @@ -0,0 +1,768 @@ +import cv2 +import math +import numpy as np +import random +import torch +from scipy import special +from scipy.stats import multivariate_normal +try: + from torchvision.transforms.functional_tensor import rgb_to_grayscale +except: + from torchvision.transforms.functional import rgb_to_grayscale + +# -------------------------------------------------------------------- # +# --------------------------- blur kernels --------------------------- # +# -------------------------------------------------------------------- # + + +# --------------------------- util functions --------------------------- # +def sigma_matrix2(sig_x, sig_y, theta): + """Calculate the rotated sigma matrix (two dimensional matrix). + + Args: + sig_x (float): + sig_y (float): + theta (float): Radian measurement. + + Returns: + ndarray: Rotated sigma matrix. + """ + d_matrix = np.array([[sig_x**2, 0], [0, sig_y**2]]) + u_matrix = np.array([[np.cos(theta), -np.sin(theta)], [np.sin(theta), np.cos(theta)]]) + return np.dot(u_matrix, np.dot(d_matrix, u_matrix.T)) + + +def mesh_grid(kernel_size): + """Generate the mesh grid, centering at zero. + + Args: + kernel_size (int): + + Returns: + xy (ndarray): with the shape (kernel_size, kernel_size, 2) + xx (ndarray): with the shape (kernel_size, kernel_size) + yy (ndarray): with the shape (kernel_size, kernel_size) + """ + ax = np.arange(-kernel_size // 2 + 1., kernel_size // 2 + 1.) + xx, yy = np.meshgrid(ax, ax) + xy = np.hstack((xx.reshape((kernel_size * kernel_size, 1)), yy.reshape(kernel_size * kernel_size, + 1))).reshape(kernel_size, kernel_size, 2) + return xy, xx, yy + + +def pdf2(sigma_matrix, grid): + """Calculate PDF of the bivariate Gaussian distribution. + + Args: + sigma_matrix (ndarray): with the shape (2, 2) + grid (ndarray): generated by :func:`mesh_grid`, + with the shape (K, K, 2), K is the kernel size. + + Returns: + kernel (ndarrray): un-normalized kernel. + """ + inverse_sigma = np.linalg.inv(sigma_matrix) + kernel = np.exp(-0.5 * np.sum(np.dot(grid, inverse_sigma) * grid, 2)) + return kernel + + +def cdf2(d_matrix, grid): + """Calculate the CDF of the standard bivariate Gaussian distribution. + Used in skewed Gaussian distribution. + + Args: + d_matrix (ndarrasy): skew matrix. + grid (ndarray): generated by :func:`mesh_grid`, + with the shape (K, K, 2), K is the kernel size. + + Returns: + cdf (ndarray): skewed cdf. + """ + rv = multivariate_normal([0, 0], [[1, 0], [0, 1]]) + grid = np.dot(grid, d_matrix) + cdf = rv.cdf(grid) + return cdf + + +def bivariate_Gaussian(kernel_size, sig_x, sig_y, theta, grid=None, isotropic=True): + """Generate a bivariate isotropic or anisotropic Gaussian kernel. + + In the isotropic mode, only `sig_x` is used. `sig_y` and `theta` is ignored. + + Args: + kernel_size (int): + sig_x (float): + sig_y (float): + theta (float): Radian measurement. + grid (ndarray, optional): generated by :func:`mesh_grid`, + with the shape (K, K, 2), K is the kernel size. Default: None + isotropic (bool): + + Returns: + kernel (ndarray): normalized kernel. + """ + if grid is None: + grid, _, _ = mesh_grid(kernel_size) + if isotropic: + sigma_matrix = np.array([[sig_x**2, 0], [0, sig_x**2]]) + else: + sigma_matrix = sigma_matrix2(sig_x, sig_y, theta) + kernel = pdf2(sigma_matrix, grid) + kernel = kernel / np.sum(kernel) + return kernel + + +def bivariate_generalized_Gaussian(kernel_size, sig_x, sig_y, theta, beta, grid=None, isotropic=True): + """Generate a bivariate generalized Gaussian kernel. + Described in `Parameter Estimation For Multivariate Generalized + Gaussian Distributions`_ + by Pascal et. al (2013). + + In the isotropic mode, only `sig_x` is used. `sig_y` and `theta` is ignored. + + Args: + kernel_size (int): + sig_x (float): + sig_y (float): + theta (float): Radian measurement. + beta (float): shape parameter, beta = 1 is the normal distribution. + grid (ndarray, optional): generated by :func:`mesh_grid`, + with the shape (K, K, 2), K is the kernel size. Default: None + + Returns: + kernel (ndarray): normalized kernel. + + .. _Parameter Estimation For Multivariate Generalized Gaussian + Distributions: https://arxiv.org/abs/1302.6498 + """ + if grid is None: + grid, _, _ = mesh_grid(kernel_size) + if isotropic: + sigma_matrix = np.array([[sig_x**2, 0], [0, sig_x**2]]) + else: + sigma_matrix = sigma_matrix2(sig_x, sig_y, theta) + inverse_sigma = np.linalg.inv(sigma_matrix) + kernel = np.exp(-0.5 * np.power(np.sum(np.dot(grid, inverse_sigma) * grid, 2), beta)) + kernel = kernel / np.sum(kernel) + return kernel + + +def bivariate_plateau(kernel_size, sig_x, sig_y, theta, beta, grid=None, isotropic=True): + """Generate a plateau-like anisotropic kernel. + 1 / (1+x^(beta)) + + Ref: https://stats.stackexchange.com/questions/203629/is-there-a-plateau-shaped-distribution + + In the isotropic mode, only `sig_x` is used. `sig_y` and `theta` is ignored. + + Args: + kernel_size (int): + sig_x (float): + sig_y (float): + theta (float): Radian measurement. + beta (float): shape parameter, beta = 1 is the normal distribution. + grid (ndarray, optional): generated by :func:`mesh_grid`, + with the shape (K, K, 2), K is the kernel size. Default: None + + Returns: + kernel (ndarray): normalized kernel. + """ + if grid is None: + grid, _, _ = mesh_grid(kernel_size) + if isotropic: + sigma_matrix = np.array([[sig_x**2, 0], [0, sig_x**2]]) + else: + sigma_matrix = sigma_matrix2(sig_x, sig_y, theta) + inverse_sigma = np.linalg.inv(sigma_matrix) + kernel = np.reciprocal(np.power(np.sum(np.dot(grid, inverse_sigma) * grid, 2), beta) + 1) + kernel = kernel / np.sum(kernel) + return kernel + + +def random_bivariate_Gaussian(kernel_size, + sigma_x_range, + sigma_y_range, + rotation_range, + noise_range=None, + isotropic=True): + """Randomly generate bivariate isotropic or anisotropic Gaussian kernels. + + In the isotropic mode, only `sigma_x_range` is used. `sigma_y_range` and `rotation_range` is ignored. + + Args: + kernel_size (int): + sigma_x_range (tuple): [0.6, 5] + sigma_y_range (tuple): [0.6, 5] + rotation range (tuple): [-math.pi, math.pi] + noise_range(tuple, optional): multiplicative kernel noise, + [0.75, 1.25]. Default: None + + Returns: + kernel (ndarray): + """ + assert kernel_size % 2 == 1, 'Kernel size must be an odd number.' + assert sigma_x_range[0] < sigma_x_range[1], 'Wrong sigma_x_range.' + sigma_x = np.random.uniform(sigma_x_range[0], sigma_x_range[1]) + if isotropic is False: + assert sigma_y_range[0] < sigma_y_range[1], 'Wrong sigma_y_range.' + assert rotation_range[0] < rotation_range[1], 'Wrong rotation_range.' + sigma_y = np.random.uniform(sigma_y_range[0], sigma_y_range[1]) + rotation = np.random.uniform(rotation_range[0], rotation_range[1]) + else: + sigma_y = sigma_x + rotation = 0 + + kernel = bivariate_Gaussian(kernel_size, sigma_x, sigma_y, rotation, isotropic=isotropic) + + # add multiplicative noise + if noise_range is not None: + assert noise_range[0] < noise_range[1], 'Wrong noise range.' + noise = np.random.uniform(noise_range[0], noise_range[1], size=kernel.shape) + kernel = kernel * noise + kernel = kernel / np.sum(kernel) + return kernel + + +def random_bivariate_generalized_Gaussian(kernel_size, + sigma_x_range, + sigma_y_range, + rotation_range, + beta_range, + noise_range=None, + isotropic=True): + """Randomly generate bivariate generalized Gaussian kernels. + + In the isotropic mode, only `sigma_x_range` is used. `sigma_y_range` and `rotation_range` is ignored. + + Args: + kernel_size (int): + sigma_x_range (tuple): [0.6, 5] + sigma_y_range (tuple): [0.6, 5] + rotation range (tuple): [-math.pi, math.pi] + beta_range (tuple): [0.5, 8] + noise_range(tuple, optional): multiplicative kernel noise, + [0.75, 1.25]. Default: None + + Returns: + kernel (ndarray): + """ + assert kernel_size % 2 == 1, 'Kernel size must be an odd number.' + assert sigma_x_range[0] < sigma_x_range[1], 'Wrong sigma_x_range.' + sigma_x = np.random.uniform(sigma_x_range[0], sigma_x_range[1]) + if isotropic is False: + assert sigma_y_range[0] < sigma_y_range[1], 'Wrong sigma_y_range.' + assert rotation_range[0] < rotation_range[1], 'Wrong rotation_range.' + sigma_y = np.random.uniform(sigma_y_range[0], sigma_y_range[1]) + rotation = np.random.uniform(rotation_range[0], rotation_range[1]) + else: + sigma_y = sigma_x + rotation = 0 + + # assume beta_range[0] < 1 < beta_range[1] + if np.random.uniform() < 0.5: + beta = np.random.uniform(beta_range[0], 1) + else: + beta = np.random.uniform(1, beta_range[1]) + + kernel = bivariate_generalized_Gaussian(kernel_size, sigma_x, sigma_y, rotation, beta, isotropic=isotropic) + + # add multiplicative noise + if noise_range is not None: + assert noise_range[0] < noise_range[1], 'Wrong noise range.' + noise = np.random.uniform(noise_range[0], noise_range[1], size=kernel.shape) + kernel = kernel * noise + kernel = kernel / np.sum(kernel) + return kernel + + +def random_bivariate_plateau(kernel_size, + sigma_x_range, + sigma_y_range, + rotation_range, + beta_range, + noise_range=None, + isotropic=True): + """Randomly generate bivariate plateau kernels. + + In the isotropic mode, only `sigma_x_range` is used. `sigma_y_range` and `rotation_range` is ignored. + + Args: + kernel_size (int): + sigma_x_range (tuple): [0.6, 5] + sigma_y_range (tuple): [0.6, 5] + rotation range (tuple): [-math.pi/2, math.pi/2] + beta_range (tuple): [1, 4] + noise_range(tuple, optional): multiplicative kernel noise, + [0.75, 1.25]. Default: None + + Returns: + kernel (ndarray): + """ + assert kernel_size % 2 == 1, 'Kernel size must be an odd number.' + assert sigma_x_range[0] < sigma_x_range[1], 'Wrong sigma_x_range.' + sigma_x = np.random.uniform(sigma_x_range[0], sigma_x_range[1]) + if isotropic is False: + assert sigma_y_range[0] < sigma_y_range[1], 'Wrong sigma_y_range.' + assert rotation_range[0] < rotation_range[1], 'Wrong rotation_range.' + sigma_y = np.random.uniform(sigma_y_range[0], sigma_y_range[1]) + rotation = np.random.uniform(rotation_range[0], rotation_range[1]) + else: + sigma_y = sigma_x + rotation = 0 + + # TODO: this may be not proper + if np.random.uniform() < 0.5: + beta = np.random.uniform(beta_range[0], 1) + else: + beta = np.random.uniform(1, beta_range[1]) + + kernel = bivariate_plateau(kernel_size, sigma_x, sigma_y, rotation, beta, isotropic=isotropic) + # add multiplicative noise + if noise_range is not None: + assert noise_range[0] < noise_range[1], 'Wrong noise range.' + noise = np.random.uniform(noise_range[0], noise_range[1], size=kernel.shape) + kernel = kernel * noise + kernel = kernel / np.sum(kernel) + + return kernel + + +def random_mixed_kernels(kernel_list, + kernel_prob, + kernel_size=21, + sigma_x_range=(0.6, 5), + sigma_y_range=(0.6, 5), + rotation_range=(-math.pi, math.pi), + betag_range=(0.5, 8), + betap_range=(0.5, 8), + noise_range=None): + """Randomly generate mixed kernels. + + Args: + kernel_list (tuple): a list name of kernel types, + support ['iso', 'aniso', 'skew', 'generalized', 'plateau_iso', + 'plateau_aniso'] + kernel_prob (tuple): corresponding kernel probability for each + kernel type + kernel_size (int): + sigma_x_range (tuple): [0.6, 5] + sigma_y_range (tuple): [0.6, 5] + rotation range (tuple): [-math.pi, math.pi] + beta_range (tuple): [0.5, 8] + noise_range(tuple, optional): multiplicative kernel noise, + [0.75, 1.25]. Default: None + + Returns: + kernel (ndarray): + """ + kernel_type = random.choices(kernel_list, kernel_prob)[0] + if kernel_type == 'iso': + kernel = random_bivariate_Gaussian( + kernel_size, sigma_x_range, sigma_y_range, rotation_range, noise_range=noise_range, isotropic=True) + elif kernel_type == 'aniso': + kernel = random_bivariate_Gaussian( + kernel_size, sigma_x_range, sigma_y_range, rotation_range, noise_range=noise_range, isotropic=False) + elif kernel_type == 'generalized_iso': + kernel = random_bivariate_generalized_Gaussian( + kernel_size, + sigma_x_range, + sigma_y_range, + rotation_range, + betag_range, + noise_range=noise_range, + isotropic=True) + elif kernel_type == 'generalized_aniso': + kernel = random_bivariate_generalized_Gaussian( + kernel_size, + sigma_x_range, + sigma_y_range, + rotation_range, + betag_range, + noise_range=noise_range, + isotropic=False) + elif kernel_type == 'plateau_iso': + kernel = random_bivariate_plateau( + kernel_size, sigma_x_range, sigma_y_range, rotation_range, betap_range, noise_range=None, isotropic=True) + elif kernel_type == 'plateau_aniso': + kernel = random_bivariate_plateau( + kernel_size, sigma_x_range, sigma_y_range, rotation_range, betap_range, noise_range=None, isotropic=False) + return kernel + + +np.seterr(divide='ignore', invalid='ignore') + + +def circular_lowpass_kernel(cutoff, kernel_size, pad_to=0): + """2D sinc filter, ref: https://dsp.stackexchange.com/questions/58301/2-d-circularly-symmetric-low-pass-filter + + Args: + cutoff (float): cutoff frequency in radians (pi is max) + kernel_size (int): horizontal and vertical size, must be odd. + pad_to (int): pad kernel size to desired size, must be odd or zero. + """ + assert kernel_size % 2 == 1, 'Kernel size must be an odd number.' + kernel = np.fromfunction( + lambda x, y: cutoff * special.j1(cutoff * np.sqrt( + (x - (kernel_size - 1) / 2)**2 + (y - (kernel_size - 1) / 2)**2)) / (2 * np.pi * np.sqrt( + (x - (kernel_size - 1) / 2)**2 + (y - (kernel_size - 1) / 2)**2)), [kernel_size, kernel_size]) + kernel[(kernel_size - 1) // 2, (kernel_size - 1) // 2] = cutoff**2 / (4 * np.pi) + kernel = kernel / np.sum(kernel) + if pad_to > kernel_size: + pad_size = (pad_to - kernel_size) // 2 + kernel = np.pad(kernel, ((pad_size, pad_size), (pad_size, pad_size))) + return kernel + + +# ------------------------------------------------------------- # +# --------------------------- noise --------------------------- # +# ------------------------------------------------------------- # + +# ----------------------- Gaussian Noise ----------------------- # + + +def generate_gaussian_noise(img, sigma=10, gray_noise=False): + """Generate Gaussian noise. + + Args: + img (Numpy array): Input image, shape (h, w, c), range [0, 1], float32. + sigma (float): Noise scale (measured in range 255). Default: 10. + + Returns: + (Numpy array): Returned noisy image, shape (h, w, c), range[0, 1], + float32. + """ + if gray_noise: + noise = np.float32(np.random.randn(*(img.shape[0:2]))) * sigma / 255. + noise = np.expand_dims(noise, axis=2).repeat(3, axis=2) + else: + noise = np.float32(np.random.randn(*(img.shape))) * sigma / 255. + return noise + + +def add_gaussian_noise(img, sigma=10, clip=True, rounds=False, gray_noise=False): + """Add Gaussian noise. + + Args: + img (Numpy array): Input image, shape (h, w, c), range [0, 1], float32. + sigma (float): Noise scale (measured in range 255). Default: 10. + + Returns: + (Numpy array): Returned noisy image, shape (h, w, c), range[0, 1], + float32. + """ + noise = generate_gaussian_noise(img, sigma, gray_noise) + out = img + noise + if clip and rounds: + out = np.clip((out * 255.0).round(), 0, 255) / 255. + elif clip: + out = np.clip(out, 0, 1) + elif rounds: + out = (out * 255.0).round() / 255. + return out + + +def generate_gaussian_noise_pt(img, sigma=10, gray_noise=0): + """Add Gaussian noise (PyTorch version). + + Args: + img (Tensor): Shape (b, c, h, w), range[0, 1], float32. + scale (float | Tensor): Noise scale. Default: 1.0. + + Returns: + (Tensor): Returned noisy image, shape (b, c, h, w), range[0, 1], + float32. + """ + b, _, h, w = img.size() + if not isinstance(sigma, (float, int)): + sigma = sigma.view(img.size(0), 1, 1, 1) + if isinstance(gray_noise, (float, int)): + cal_gray_noise = gray_noise > 0 + else: + gray_noise = gray_noise.view(b, 1, 1, 1) + cal_gray_noise = torch.sum(gray_noise) > 0 + + if cal_gray_noise: + noise_gray = torch.randn(*img.size()[2:4], dtype=img.dtype, device=img.device) * sigma / 255. + noise_gray = noise_gray.view(b, 1, h, w) + + # always calculate color noise + noise = torch.randn(*img.size(), dtype=img.dtype, device=img.device) * sigma / 255. + + if cal_gray_noise: + noise = noise * (1 - gray_noise) + noise_gray * gray_noise + return noise + + +def add_gaussian_noise_pt(img, sigma=10, gray_noise=0, clip=True, rounds=False): + """Add Gaussian noise (PyTorch version). + + Args: + img (Tensor): Shape (b, c, h, w), range[0, 1], float32. + scale (float | Tensor): Noise scale. Default: 1.0. + + Returns: + (Tensor): Returned noisy image, shape (b, c, h, w), range[0, 1], + float32. + """ + noise = generate_gaussian_noise_pt(img, sigma, gray_noise) + out = img + noise + if clip and rounds: + out = torch.clamp((out * 255.0).round(), 0, 255) / 255. + elif clip: + out = torch.clamp(out, 0, 1) + elif rounds: + out = (out * 255.0).round() / 255. + return out + + +# ----------------------- Random Gaussian Noise ----------------------- # +def random_generate_gaussian_noise(img, sigma_range=(0, 10), gray_prob=0): + sigma = np.random.uniform(sigma_range[0], sigma_range[1]) + if np.random.uniform() < gray_prob: + gray_noise = True + else: + gray_noise = False + return generate_gaussian_noise(img, sigma, gray_noise) + + +def random_add_gaussian_noise(img, sigma_range=(0, 1.0), gray_prob=0, clip=True, rounds=False): + noise = random_generate_gaussian_noise(img, sigma_range, gray_prob) + out = img + noise + if clip and rounds: + out = np.clip((out * 255.0).round(), 0, 255) / 255. + elif clip: + out = np.clip(out, 0, 1) + elif rounds: + out = (out * 255.0).round() / 255. + return out + + +def random_generate_gaussian_noise_pt(img, sigma_range=(0, 10), gray_prob=0): + sigma = torch.rand( + img.size(0), dtype=img.dtype, device=img.device) * (sigma_range[1] - sigma_range[0]) + sigma_range[0] + gray_noise = torch.rand(img.size(0), dtype=img.dtype, device=img.device) + gray_noise = (gray_noise < gray_prob).float() + return generate_gaussian_noise_pt(img, sigma, gray_noise) + + +def random_add_gaussian_noise_pt(img, sigma_range=(0, 1.0), gray_prob=0, clip=True, rounds=False): + noise = random_generate_gaussian_noise_pt(img, sigma_range, gray_prob) + out = img + noise + if clip and rounds: + out = torch.clamp((out * 255.0).round(), 0, 255) / 255. + elif clip: + out = torch.clamp(out, 0, 1) + elif rounds: + out = (out * 255.0).round() / 255. + return out + + +# ----------------------- Poisson (Shot) Noise ----------------------- # + + +def generate_poisson_noise(img, scale=1.0, gray_noise=False): + """Generate poisson noise. + + Ref: https://github.com/scikit-image/scikit-image/blob/main/skimage/util/noise.py#L37-L219 + + Args: + img (Numpy array): Input image, shape (h, w, c), range [0, 1], float32. + scale (float): Noise scale. Default: 1.0. + gray_noise (bool): Whether generate gray noise. Default: False. + + Returns: + (Numpy array): Returned noisy image, shape (h, w, c), range[0, 1], + float32. + """ + if gray_noise: + img = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY) + # round and clip image for counting vals correctly + img = np.clip((img * 255.0).round(), 0, 255) / 255. + vals = len(np.unique(img)) + vals = 2**np.ceil(np.log2(vals)) + out = np.float32(np.random.poisson(img * vals) / float(vals)) + noise = out - img + if gray_noise: + noise = np.repeat(noise[:, :, np.newaxis], 3, axis=2) + return noise * scale + + +def add_poisson_noise(img, scale=1.0, clip=True, rounds=False, gray_noise=False): + """Add poisson noise. + + Args: + img (Numpy array): Input image, shape (h, w, c), range [0, 1], float32. + scale (float): Noise scale. Default: 1.0. + gray_noise (bool): Whether generate gray noise. Default: False. + + Returns: + (Numpy array): Returned noisy image, shape (h, w, c), range[0, 1], + float32. + """ + noise = generate_poisson_noise(img, scale, gray_noise) + out = img + noise + if clip and rounds: + out = np.clip((out * 255.0).round(), 0, 255) / 255. + elif clip: + out = np.clip(out, 0, 1) + elif rounds: + out = (out * 255.0).round() / 255. + return out + + +def generate_poisson_noise_pt(img, scale=1.0, gray_noise=0): + """Generate a batch of poisson noise (PyTorch version) + + Args: + img (Tensor): Input image, shape (b, c, h, w), range [0, 1], float32. + scale (float | Tensor): Noise scale. Number or Tensor with shape (b). + Default: 1.0. + gray_noise (float | Tensor): 0-1 number or Tensor with shape (b). + 0 for False, 1 for True. Default: 0. + + Returns: + (Tensor): Returned noisy image, shape (b, c, h, w), range[0, 1], + float32. + """ + b, _, h, w = img.size() + if isinstance(gray_noise, (float, int)): + cal_gray_noise = gray_noise > 0 + else: + gray_noise = gray_noise.view(b, 1, 1, 1) + cal_gray_noise = torch.sum(gray_noise) > 0 + if cal_gray_noise: + img_gray = rgb_to_grayscale(img, num_output_channels=1) + # round and clip image for counting vals correctly + img_gray = torch.clamp((img_gray * 255.0).round(), 0, 255) / 255. + # use for-loop to get the unique values for each sample + vals_list = [len(torch.unique(img_gray[i, :, :, :])) for i in range(b)] + vals_list = [2**np.ceil(np.log2(vals)) for vals in vals_list] + vals = img_gray.new_tensor(vals_list).view(b, 1, 1, 1) + out = torch.poisson(img_gray * vals) / vals + noise_gray = out - img_gray + noise_gray = noise_gray.expand(b, 3, h, w) + + # always calculate color noise + # round and clip image for counting vals correctly + img = torch.clamp((img * 255.0).round(), 0, 255) / 255. + # use for-loop to get the unique values for each sample + vals_list = [len(torch.unique(img[i, :, :, :])) for i in range(b)] + vals_list = [2**np.ceil(np.log2(vals)) for vals in vals_list] + vals = img.new_tensor(vals_list).view(b, 1, 1, 1) + out = torch.poisson(img * vals) / vals + noise = out - img + if cal_gray_noise: + noise = noise * (1 - gray_noise) + noise_gray * gray_noise + if not isinstance(scale, (float, int)): + scale = scale.view(b, 1, 1, 1) + return noise * scale + + +def add_poisson_noise_pt(img, scale=1.0, clip=True, rounds=False, gray_noise=0): + """Add poisson noise to a batch of images (PyTorch version). + + Args: + img (Tensor): Input image, shape (b, c, h, w), range [0, 1], float32. + scale (float | Tensor): Noise scale. Number or Tensor with shape (b). + Default: 1.0. + gray_noise (float | Tensor): 0-1 number or Tensor with shape (b). + 0 for False, 1 for True. Default: 0. + + Returns: + (Tensor): Returned noisy image, shape (b, c, h, w), range[0, 1], + float32. + """ + noise = generate_poisson_noise_pt(img, scale, gray_noise) + out = img + noise + if clip and rounds: + out = torch.clamp((out * 255.0).round(), 0, 255) / 255. + elif clip: + out = torch.clamp(out, 0, 1) + elif rounds: + out = (out * 255.0).round() / 255. + return out + + +# ----------------------- Random Poisson (Shot) Noise ----------------------- # + + +def random_generate_poisson_noise(img, scale_range=(0, 1.0), gray_prob=0): + scale = np.random.uniform(scale_range[0], scale_range[1]) + if np.random.uniform() < gray_prob: + gray_noise = True + else: + gray_noise = False + return generate_poisson_noise(img, scale, gray_noise) + + +def random_add_poisson_noise(img, scale_range=(0, 1.0), gray_prob=0, clip=True, rounds=False): + noise = random_generate_poisson_noise(img, scale_range, gray_prob) + out = img + noise + if clip and rounds: + out = np.clip((out * 255.0).round(), 0, 255) / 255. + elif clip: + out = np.clip(out, 0, 1) + elif rounds: + out = (out * 255.0).round() / 255. + return out + + +def random_generate_poisson_noise_pt(img, scale_range=(0, 1.0), gray_prob=0): + scale = torch.rand( + img.size(0), dtype=img.dtype, device=img.device) * (scale_range[1] - scale_range[0]) + scale_range[0] + gray_noise = torch.rand(img.size(0), dtype=img.dtype, device=img.device) + gray_noise = (gray_noise < gray_prob).float() + return generate_poisson_noise_pt(img, scale, gray_noise) + + +def random_add_poisson_noise_pt(img, scale_range=(0, 1.0), gray_prob=0, clip=True, rounds=False): + noise = random_generate_poisson_noise_pt(img, scale_range, gray_prob) + out = img + noise + if clip and rounds: + out = torch.clamp((out * 255.0).round(), 0, 255) / 255. + elif clip: + out = torch.clamp(out, 0, 1) + elif rounds: + out = (out * 255.0).round() / 255. + return out + + +# ------------------------------------------------------------------------ # +# --------------------------- JPEG compression --------------------------- # +# ------------------------------------------------------------------------ # + + +def add_jpg_compression(img, quality=90): + """Add JPG compression artifacts. + + Args: + img (Numpy array): Input image, shape (h, w, c), range [0, 1], float32. + quality (float): JPG compression quality. 0 for lowest quality, 100 for + best quality. Default: 90. + + Returns: + (Numpy array): Returned image after JPG, shape (h, w, c), range[0, 1], + float32. + """ + img = np.clip(img, 0, 1) + encode_param = [int(cv2.IMWRITE_JPEG_QUALITY), quality] + _, encimg = cv2.imencode('.jpg', img * 255., encode_param) + img = np.float32(cv2.imdecode(encimg, 1)) / 255. + return img + + +def random_add_jpg_compression(img, quality_range=(90, 100)): + """Randomly add JPG compression artifacts. + + Args: + img (Numpy array): Input image, shape (h, w, c), range [0, 1], float32. + quality_range (tuple[float] | list[float]): JPG compression quality + range. 0 for lowest quality, 100 for best quality. + Default: (90, 100). + + Returns: + (Numpy array): Returned image after JPG, shape (h, w, c), range[0, 1], + float32. + """ + quality = np.random.uniform(quality_range[0], quality_range[1]) + return add_jpg_compression(img, quality) -- cgit v1.2.3