TEST_CS_ISTA_Net.py

import torch
import torch.nn as nn
import torch.nn.functional as F
import scipy.io as sio
import numpy as np
import os
import glob
from time import time
import math
from torch.nn import init
import copy
import cv2
from skimage.measure import compare_ssim as ssim
from argparse import ArgumentParser

parser = ArgumentParser(description='ISTA-Net')

parser.add_argument('--epoch_num', type=int, default=60, help='epoch number of model')
parser.add_argument('--layer_num', type=int, default=9, help='phase number of ISTA-Net')
parser.add_argument('--learning_rate', type=float, default=1e-4, help='learning rate')
parser.add_argument('--group_num', type=int, default=1, help='group number for training')
parser.add_argument('--cs_ratio', type=int, default=1, help='from {1, 4, 10, 25, 40, 50}')
parser.add_argument('--gpu_list', type=str, default='0', help='gpu index')

parser.add_argument('--matrix_dir', type=str, default='sampling_matrix', help='sampling matrix directory')
parser.add_argument('--model_dir', type=str, default='model', help='trained or pre-trained model directory')
parser.add_argument('--data_dir', type=str, default='data', help='training or test data directory')
parser.add_argument('--log_dir', type=str, default='log', help='log directory')
parser.add_argument('--result_dir', type=str, default='result', help='result directory')
parser.add_argument('--test_name', type=str, default='Set11', help='name of test set')

args = parser.parse_args()


epoch_num = args.epoch_num
learning_rate = args.learning_rate
layer_num = args.layer_num
group_num = args.group_num
cs_ratio = args.cs_ratio
gpu_list = args.gpu_list
test_name = args.test_name


os.environ["CUDA_DEVICE_ORDER"] = "PCI_BUS_ID"
os.environ["CUDA_VISIBLE_DEVICES"] = gpu_list


device = torch.device("cuda:0" if torch.cuda.is_available() else "cpu")

ratio_dict = {1: 10, 4: 43, 10: 109, 25: 272, 30: 327, 40: 436, 50: 545}

n_input = ratio_dict[cs_ratio]
n_output = 1089
nrtrain = 88912
batch_size = 64


# Load CS Sampling Matrix: phi
Phi_data_Name = './%s/phi_0_%d_1089.mat' % (args.matrix_dir, cs_ratio)
Phi_data = sio.loadmat(Phi_data_Name)
Phi_input = Phi_data['phi']


Qinit_Name = './%s/Initialization_Matrix_%d.mat' % (args.matrix_dir, cs_ratio)

# Computing Initialization Matrix:
if os.path.exists(Qinit_Name):
    Qinit_data = sio.loadmat(Qinit_Name)
    Qinit = Qinit_data['Qinit']

else:
    Training_data_Name = 'Training_Data.mat'
    Training_data = sio.loadmat('./%s/%s' % (args.data_dir, Training_data_Name))
    Training_labels = Training_data['labels']

    X_data = Training_labels.transpose()
    Y_data = np.dot(Phi_input, X_data)
    Y_YT = np.dot(Y_data, Y_data.transpose())
    X_YT = np.dot(X_data, Y_data.transpose())
    Qinit = np.dot(X_YT, np.linalg.inv(Y_YT))
    del X_data, Y_data, X_YT, Y_YT
    sio.savemat(Qinit_Name, {'Qinit': Qinit})


# Define ISTA-Net Block
class BasicBlock(torch.nn.Module):
    def __init__(self):
        super(BasicBlock, self).__init__()

        self.lambda_step = nn.Parameter(torch.Tensor([0.5]))
        self.soft_thr = nn.Parameter(torch.Tensor([0.01]))

        self.conv1_forward = nn.Parameter(init.xavier_normal_(torch.Tensor(32, 1, 3, 3)))
        self.conv2_forward = nn.Parameter(init.xavier_normal_(torch.Tensor(32, 32, 3, 3)))
        self.conv1_backward = nn.Parameter(init.xavier_normal_(torch.Tensor(32, 32, 3, 3)))
        self.conv2_backward = nn.Parameter(init.xavier_normal_(torch.Tensor(1, 32, 3, 3)))

    def forward(self, x, PhiTPhi, PhiTb):
        x = x - self.lambda_step * torch.mm(x, PhiTPhi)
        x = x + self.lambda_step * PhiTb
        x_input = x.view(-1, 1, 33, 33)

        x = F.conv2d(x_input, self.conv1_forward, padding=1)
        x = F.relu(x)
        x_forward = F.conv2d(x, self.conv2_forward, padding=1)

        x = torch.mul(torch.sign(x_forward), F.relu(torch.abs(x_forward) - self.soft_thr))

        x = F.conv2d(x, self.conv1_backward, padding=1)
        x = F.relu(x)
        x_backward = F.conv2d(x, self.conv2_backward, padding=1)

        x_pred = x_backward.view(-1, 1089)

        x = F.conv2d(x_forward, self.conv1_backward, padding=1)
        x = F.relu(x)
        x_est = F.conv2d(x, self.conv2_backward, padding=1)
        symloss = x_est - x_input

        return [x_pred, symloss]


# Define ISTA-Net
class ISTANet(torch.nn.Module):
    def __init__(self, LayerNo):
        super(ISTANet, self).__init__()
        onelayer = []
        self.LayerNo = LayerNo

        for i in range(LayerNo):
            onelayer.append(BasicBlock())

        self.fcs = nn.ModuleList(onelayer)

    def forward(self, Phix, Phi, Qinit):

        PhiTPhi = torch.mm(torch.transpose(Phi, 0, 1), Phi)
        PhiTb = torch.mm(Phix, Phi)

        x = torch.mm(Phix, torch.transpose(Qinit, 0, 1))

        layers_sym = []   # for computing symmetric loss

        for i in range(self.LayerNo):
            [x, layer_sym] = self.fcs[i](x, PhiTPhi, PhiTb)
            layers_sym.append(layer_sym)

        x_final = x

        return [x_final, layers_sym]


model = ISTANet(layer_num)
model = nn.DataParallel(model)
model = model.to(device)


optimizer = torch.optim.Adam(model.parameters(), lr=learning_rate)

model_dir = "./%s/CS_ISTA_Net_layer_%d_group_%d_ratio_%d_lr_%.4f" % (args.model_dir, layer_num, group_num, cs_ratio, learning_rate)

# Load pre-trained model with epoch number
model.load_state_dict(torch.load('./%s/net_params_%d.pkl' % (model_dir, epoch_num)))

def rgb2ycbcr(rgb):
    m = np.array([[ 65.481, 128.553, 24.966],
                  [-37.797, -74.203, 112],
                  [ 112, -93.786, -18.214]])
    shape = rgb.shape
    if len(shape) == 3:
        rgb = rgb.reshape((shape[0] * shape[1], 3))
    ycbcr = np.dot(rgb, m.transpose() / 255.)
    ycbcr[:,0] += 16.
    ycbcr[:,1:] += 128.
    return ycbcr.reshape(shape)

# ITU-R BT.601
# https://en.wikipedia.org/wiki/YCbCr
# YUV -> RGB
def ycbcr2rgb(ycbcr):
    m = np.array([[ 65.481, 128.553, 24.966],
                  [-37.797, -74.203, 112],
                  [ 112, -93.786, -18.214]])
    shape = ycbcr.shape
    if len(shape) == 3:
        ycbcr = ycbcr.reshape((shape[0] * shape[1], 3))
    rgb = copy.deepcopy(ycbcr)
    rgb[:,0] -= 16.
    rgb[:,1:] -= 128.
    rgb = np.dot(rgb, np.linalg.inv(m.transpose()) * 255.)
    return rgb.clip(0, 255).reshape(shape)

def imread_CS_py(Iorg):
    block_size = 33
    [row, col] = Iorg.shape
    row_pad = block_size-np.mod(row,block_size)
    col_pad = block_size-np.mod(col,block_size)
    Ipad = np.concatenate((Iorg, np.zeros([row, col_pad])), axis=1)
    Ipad = np.concatenate((Ipad, np.zeros([row_pad, col+col_pad])), axis=0)
    [row_new, col_new] = Ipad.shape

    return [Iorg, row, col, Ipad, row_new, col_new]


def img2col_py(Ipad, block_size):
    [row, col] = Ipad.shape
    row_block = row/block_size
    col_block = col/block_size
    block_num = int(row_block*col_block)
    img_col = np.zeros([block_size**2, block_num])
    count = 0
    for x in range(0, row-block_size+1, block_size):
        for y in range(0, col-block_size+1, block_size):
            img_col[:, count] = Ipad[x:x+block_size, y:y+block_size].reshape([-1])
            # img_col[:, count] = Ipad[x:x+block_size, y:y+block_size].transpose().reshape([-1])
            count = count + 1
    return img_col


def col2im_CS_py(X_col, row, col, row_new, col_new):
    block_size = 33
    X0_rec = np.zeros([row_new, col_new])
    count = 0
    for x in range(0, row_new-block_size+1, block_size):
        for y in range(0, col_new-block_size+1, block_size):
            X0_rec[x:x+block_size, y:y+block_size] = X_col[:, count].reshape([block_size, block_size])
            # X0_rec[x:x+block_size, y:y+block_size] = X_col[:, count].reshape([block_size, block_size]).transpose()
            count = count + 1
    X_rec = X0_rec[:row, :col]
    return X_rec


def psnr(img1, img2):
    img1.astype(np.float32)
    img2.astype(np.float32)
    mse = np.mean((img1 - img2) ** 2)
    if mse == 0:
        return 100
    PIXEL_MAX = 255.0
    return 20 * math.log10(PIXEL_MAX / math.sqrt(mse))


test_dir = os.path.join(args.data_dir, test_name)
filepaths = glob.glob(test_dir + '/*.tif')

result_dir = os.path.join(args.result_dir, test_name)
if not os.path.exists(result_dir):
    os.makedirs(result_dir)


ImgNum = len(filepaths)
PSNR_All = np.zeros([1, ImgNum], dtype=np.float32)
SSIM_All = np.zeros([1, ImgNum], dtype=np.float32)


Phi = torch.from_numpy(Phi_input).type(torch.FloatTensor)
Phi = Phi.to(device)


Qinit = torch.from_numpy(Qinit).type(torch.FloatTensor)
Qinit = Qinit.to(device)

print('\n')
print("CS Reconstruction Start")

with torch.no_grad():
    for img_no in range(ImgNum):

        imgName = filepaths[img_no]

        Img = cv2.imread(imgName, 1)

        Img_yuv = cv2.cvtColor(Img, cv2.COLOR_BGR2YCrCb)
        Img_rec_yuv = Img_yuv.copy()

        Iorg_y = Img_yuv[:,:,0]

        [Iorg, row, col, Ipad, row_new, col_new] = imread_CS_py(Iorg_y)
        Icol = img2col_py(Ipad, 33).transpose()/255.0

        Img_output = Icol

        start = time()

        batch_x = torch.from_numpy(Img_output)
        batch_x = batch_x.type(torch.FloatTensor)
        batch_x = batch_x.to(device)

        Phix = torch.mm(batch_x, torch.transpose(Phi, 0, 1))

        [x_output, loss_layers_sym] = model(Phix, Phi, Qinit)

        end = time()

        Prediction_value = x_output.cpu().data.numpy()

        # loss_sym = torch.mean(torch.pow(loss_layers_sym[0], 2))
        # for k in range(layer_num - 1):
        #     loss_sym += torch.mean(torch.pow(loss_layers_sym[k + 1], 2))
        #
        # loss_sym = loss_sym.cpu().data.numpy()

        X_rec = np.clip(col2im_CS_py(Prediction_value.transpose(), row, col, row_new, col_new), 0, 1)

        rec_PSNR = psnr(X_rec*255, Iorg.astype(np.float64))
        rec_SSIM = ssim(X_rec*255, Iorg.astype(np.float64), data_range=255)

        print("[%02d/%02d] Run time for %s is %.4f, PSNR is %.2f, SSIM is %.4f" % (img_no, ImgNum, imgName, (end - start), rec_PSNR, rec_SSIM))

        Img_rec_yuv[:,:,0] = X_rec*255

        im_rec_rgb = cv2.cvtColor(Img_rec_yuv, cv2.COLOR_YCrCb2BGR)
        im_rec_rgb = np.clip(im_rec_rgb, 0, 255).astype(np.uint8)

        resultName = imgName.replace(args.data_dir, args.result_dir)
        cv2.imwrite("%s_ISTA_Net_ratio_%d_epoch_%d_PSNR_%.2f_SSIM_%.4f.png" % (resultName, cs_ratio, epoch_num, rec_PSNR, rec_SSIM), im_rec_rgb)
        del x_output

        PSNR_All[0, img_no] = rec_PSNR
        SSIM_All[0, img_no] = rec_SSIM

print('\n')
output_data = "CS ratio is %d, Avg PSNR/SSIM for %s is %.2f/%.4f, Epoch number of model is %d \n" % (cs_ratio, args.test_name, np.mean(PSNR_All), np.mean(SSIM_All), epoch_num)
print(output_data)

output_file_name = "./%s/PSNR_SSIM_Results_CS_ISTA_Net_layer_%d_group_%d_ratio_%d_lr_%.4f.txt" % (args.log_dir, layer_num, group_num, cs_ratio, learning_rate)

output_file = open(output_file_name, 'a')
output_file.write(output_data)
output_file.close()

print("CS Reconstruction End")