import cv2
import math
import numpy as np
import os
import torch
from basicsr.archs.rrdbnet_arch import RRDBNet
from torch.hub import download_url_to_file, get_dir
from torch.nn import functional as F
from urllib.parse import urlparse
ROOT_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
class RealESRGANer():
def __init__(self, scale, model_path, tile=0, tile_pad=10, pre_pad=10, half=False):
self.scale = scale
self.tile_size = tile
self.tile_pad = tile_pad
self.pre_pad = pre_pad
self.mod_scale = None
self.half = half
# initialize model
self.device = torch.device('cuda' if torch.cuda.is_available() else 'cpu')
model = RRDBNet(num_in_ch=3, num_out_ch=3, num_feat=64, num_block=23, num_grow_ch=32, scale=scale)
if model_path.startswith('https://'):
model_path = load_file_from_url(
url=model_path, model_dir='realesrgan/weights', progress=True, file_name=None)
loadnet = torch.load(model_path)
if 'params_ema' in loadnet:
keyname = 'params_ema'
else:
keyname = 'params'
model.load_state_dict(loadnet[keyname], strict=True)
model.eval()
self.model = model.to(self.device)
if self.half:
self.model = self.model.half()
def pre_process(self, img):
img = torch.from_numpy(np.transpose(img, (2, 0, 1))).float()
self.img = img.unsqueeze(0).to(self.device)
if self.half:
self.img = self.img.half()
# pre_pad
if self.pre_pad != 0:
self.img = F.pad(self.img, (0, self.pre_pad, 0, self.pre_pad), 'reflect')
# mod pad
if self.scale == 2:
self.mod_scale = 2
elif self.scale == 1:
self.mod_scale = 4
if self.mod_scale is not None:
self.mod_pad_h, self.mod_pad_w = 0, 0
_, _, h, w = self.img.size()
if (h % self.mod_scale != 0):
self.mod_pad_h = (self.mod_scale - h % self.mod_scale)
if (w % self.mod_scale != 0):
self.mod_pad_w = (self.mod_scale - w % self.mod_scale)
self.img = F.pad(self.img, (0, self.mod_pad_w, 0, self.mod_pad_h), 'reflect')
def process(self):
self.output = self.model(self.img)
def tile_process(self):
"""Modified from: https://github.com/ata4/esrgan-launcher
"""
batch, channel, height, width = self.img.shape
output_height = height * self.scale
output_width = width * self.scale
output_shape = (batch, channel, output_height, output_width)
# start with black image
self.output = self.img.new_zeros(output_shape)
tiles_x = math.ceil(width / self.tile_size)
tiles_y = math.ceil(height / self.tile_size)
# loop over all tiles
for y in range(tiles_y):
for x in range(tiles_x):
# extract tile from input image
ofs_x = x * self.tile_size
ofs_y = y * self.tile_size
# input tile area on total image
input_start_x = ofs_x
input_end_x = min(ofs_x + self.tile_size, width)
input_start_y = ofs_y
input_end_y = min(ofs_y + self.tile_size, height)
# input tile area on total image with padding
input_start_x_pad = max(input_start_x - self.tile_pad, 0)
input_end_x_pad = min(input_end_x + self.tile_pad, width)
input_start_y_pad = max(input_start_y - self.tile_pad, 0)
input_end_y_pad = min(input_end_y + self.tile_pad, height)
# input tile dimensions
input_tile_width = input_end_x - input_start_x
input_tile_height = input_end_y - input_start_y
tile_idx = y * tiles_x + x + 1
input_tile = self.img[:, :, input_start_y_pad:input_end_y_pad, input_start_x_pad:input_end_x_pad]
# upscale tile
try:
with torch.no_grad():
output_tile = self.model(input_tile)
except Exception as error:
print('Error', error)
print(f'\tTile {tile_idx}/{tiles_x * tiles_y}')
# output tile area on total image
output_start_x = input_start_x * self.scale
output_end_x = input_end_x * self.scale
output_start_y = input_start_y * self.scale
output_end_y = input_end_y * self.scale
# output tile area without padding
output_start_x_tile = (input_start_x - input_start_x_pad) * self.scale
output_end_x_tile = output_start_x_tile + input_tile_width * self.scale
output_start_y_tile = (input_start_y - input_start_y_pad) * self.scale
output_end_y_tile = output_start_y_tile + input_tile_height * self.scale
# put tile into output image
self.output[:, :, output_start_y:output_end_y,
output_start_x:output_end_x] = output_tile[:, :, output_start_y_tile:output_end_y_tile,
output_start_x_tile:output_end_x_tile]
def post_process(self):
# remove extra pad
if self.mod_scale is not None:
_, _, h, w = self.output.size()
self.output = self.output[:, :, 0:h - self.mod_pad_h * self.scale, 0:w - self.mod_pad_w * self.scale]
# remove prepad
if self.pre_pad != 0:
_, _, h, w = self.output.size()
self.output = self.output[:, :, 0:h - self.pre_pad * self.scale, 0:w - self.pre_pad * self.scale]
return self.output
@torch.no_grad()
def enhance(self, img, outscale=None, alpha_upsampler='realesrgan'):
h_input, w_input = img.shape[0:2]
# img: numpy
img = img.astype(np.float32)
if np.max(img) > 255: # 16-bit image
max_range = 65535
print('\tInput is a 16-bit image')
else:
max_range = 255
img = img / max_range
if len(img.shape) == 2: # gray image
img_mode = 'L'
img = cv2.cvtColor(img, cv2.COLOR_GRAY2RGB)
elif img.shape[2] == 4: # RGBA image with alpha channel
img_mode = 'RGBA'
alpha = img[:, :, 3]
img = img[:, :, 0:3]
img = cv2.cvtColor(img, cv2.COLOR_BGR2RGB)
if alpha_upsampler == 'realesrgan':
alpha = cv2.cvtColor(alpha, cv2.COLOR_GRAY2RGB)
else:
img_mode = 'RGB'
img = cv2.cvtColor(img, cv2.COLOR_BGR2RGB)
# ------------------- process image (without the alpha channel) ------------------- #
self.pre_process(img)
if self.tile_size > 0:
self.tile_process()
else:
self.process()
output_img = self.post_process()
output_img = output_img.data.squeeze().float().cpu().clamp_(0, 1).numpy()
output_img = np.transpose(output_img[[2, 1, 0], :, :], (1, 2, 0))
if img_mode == 'L':
output_img = cv2.cvtColor(output_img, cv2.COLOR_BGR2GRAY)
# ------------------- process the alpha channel if necessary ------------------- #
if img_mode == 'RGBA':
if alpha_upsampler == 'realesrgan':
self.pre_process(alpha)
if self.tile_size > 0:
self.tile_process()
else:
self.process()
output_alpha = self.post_process()
output_alpha = output_alpha.data.squeeze().float().cpu().clamp_(0, 1).numpy()
output_alpha = np.transpose(output_alpha[[2, 1, 0], :, :], (1, 2, 0))
output_alpha = cv2.cvtColor(output_alpha, cv2.COLOR_BGR2GRAY)
else:
h, w = alpha.shape[0:2]
output_alpha = cv2.resize(alpha, (w * self.scale, h * self.scale), interpolation=cv2.INTER_LINEAR)
# merge the alpha channel
output_img = cv2.cvtColor(output_img, cv2.COLOR_BGR2BGRA)
output_img[:, :, 3] = output_alpha
# ------------------------------ return ------------------------------ #
if max_range == 65535: # 16-bit image
output = (output_img * 65535.0).round().astype(np.uint16)
else:
output = (output_img * 255.0).round().astype(np.uint8)
if outscale is not None and outscale != float(self.scale):
output = cv2.resize(
output, (
int(w_input * outscale),
int(h_input * outscale),
), interpolation=cv2.INTER_LANCZOS4)
return output, img_mode
def load_file_from_url(url, model_dir=None, progress=True, file_name=None):
"""Ref:https://github.com/1adrianb/face-alignment/blob/master/face_alignment/utils.py
"""
if model_dir is None:
hub_dir = get_dir()
model_dir = os.path.join(hub_dir, 'checkpoints')
os.makedirs(os.path.join(ROOT_DIR, model_dir), exist_ok=True)
parts = urlparse(url)
filename = os.path.basename(parts.path)
if file_name is not None:
filename = file_name
cached_file = os.path.abspath(os.path.join(ROOT_DIR, model_dir, filename))
if not os.path.exists(cached_file):
print(f'Downloading: "{url}" to {cached_file}\n')
download_url_to_file(url, cached_file, hash_prefix=None, progress=progress)
return cached_file