517 lines
20 KiB
Python
517 lines
20 KiB
Python
import datetime
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import os
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import time
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import ffmpeg
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import torch
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import cv2
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import numpy as np
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from multiprocessing import Process, Manager
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from threading import Thread
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from read_data import LoadImages, LoadStreams
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import torch.backends.cudnn as cudnn
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import torch.nn.functional as F
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import torchvision
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from PIL import Image, ImageDraw, ImageFont
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class YOLO_Segment():
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time_reference = datetime.datetime.now()
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counter_frame = 0
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processed_fps = 0
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def __init__(self,video_path=None):
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self.device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
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self.model = torch.load('weight/segment/yolov5s-seg.pt', map_location=self.device)['model'].float().fuse()
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self.classes = self.model.names
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self.frame = [None]
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if video_path is not None:
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self.video_name = video_path
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else:
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self.video_name = 'vid2.mp4' # A default video file
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self.dataset = LoadImages(self.video_name)
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self.names = self.model.names
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def use_webcam(self, source):
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# self.dataset.release() # Release any existing video capture
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# self.cap = cv2.VideoCapture(0) # Open default webcam
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# print('use_webcam')
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source = source
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self.imgsz = 640
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cudnn.benchmark = True
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self.dataset = LoadStreams(source, img_size=self.imgsz)
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def class_to_label(self, x):
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return self.classes[int(x)]
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def get_frame(self):
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colors = Colors()
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for im0s in self.dataset:
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# print(self.dataset.mode)
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# print(self.dataset)
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if self.dataset.mode == 'stream':
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image = im0s[0].copy()
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else:
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image = im0s.copy()
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img = image[:, :, ::-1].transpose(2, 0, 1) # BGR to RGB, to 3x416x416
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img0 = img.copy()
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img = torch.tensor(img0)
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img = img.float() # uint8 to fp16/32
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img /= 255.0 # 0 - 255 to 0.0 - 1.0
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if img.ndimension() == 3:
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img = img.unsqueeze(0)
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img = img.to(self.device)
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self.model.to(self.device)
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pred, proto = self.model(img)[:2]
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pred = non_max_suppression(pred, conf_thres=0.25, iou_thres=0.45, max_det=1000, nm=32)
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for i, det in enumerate(pred): # per image
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annotator = Annotator(image, line_width=3, example=str(self.names))
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if len(det):
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masks = process_mask(proto[i], det[:, 6:], det[:, :4], img.shape[2:], upsample=True) # HWC
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det[:, :4] = scale_boxes(img.shape[2:], det[:, :4], img.shape).round() # rescale boxes to im0 size
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segments = reversed(masks2segments(masks))
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segments = [scale_segments(img.shape[2:], x, img.shape, normalize=True) for x in segments]
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# Print results
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txt = ""
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for c in det[:, 5].unique():
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n = (det[:, 5] == c).sum() # detections per class
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txt += f"{n} {self.classes[int(c)]}{'s' * (n > 1)}, " # add to string
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annotator.masks(masks,
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colors=[colors(x, True) for x in det[:, 5]],
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im_gpu=img[i])
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im0 = annotator.result()
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# Draw the number of people on the frame and display it
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ret, jpeg = cv2.imencode(".jpg", im0)
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return jpeg.tobytes(), txt
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class Colors:
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# Ultralytics color palette https://ultralytics.com/
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def __init__(self):
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# hex = matplotlib.colors.TABLEAU_COLORS.values()
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hexs = ('FF3838', 'FF9D97', 'FF701F', 'FFB21D', 'CFD231', '48F90A', '92CC17', '3DDB86', '1A9334', '00D4BB',
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'2C99A8', '00C2FF', '344593', '6473FF', '0018EC', '8438FF', '520085', 'CB38FF', 'FF95C8', 'FF37C7')
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self.palette = [self.hex2rgb(f'#{c}') for c in hexs]
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self.n = len(self.palette)
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def __call__(self, i, bgr=False):
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c = self.palette[int(i) % self.n]
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return (c[2], c[1], c[0]) if bgr else c
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@staticmethod
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def hex2rgb(h): # rgb order (PIL)
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return tuple(int(h[1 + i:1 + i + 2], 16) for i in (0, 2, 4))
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class Annotator:
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# YOLOv5 Annotator for train/val mosaics and jpgs and detect/hub inference annotations
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def __init__(self, im, line_width=None, font_size=None, font='Arial.ttf', pil=False, example='abc'):
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assert im.data.contiguous, 'Image not contiguous. Apply np.ascontiguousarray(im) to Annotator() input images.'
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non_ascii = not is_ascii(example) # non-latin labels, i.e. asian, arabic, cyrillic
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self.pil = pil or non_ascii
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if self.pil: # use PIL
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self.im = im if isinstance(im, Image.Image) else Image.fromarray(im)
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self.draw = ImageDraw.Draw(self.im)
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self.font = 'Arial.Unicode.ttf'
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else: # use cv2
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self.im = im
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self.lw = line_width or max(round(sum(im.shape) / 2 * 0.003), 2) # line width
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def masks(self, masks, colors, im_gpu, alpha=0.5):
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"""Plot masks at once.
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Args:
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masks (tensor): predicted masks on cuda, shape: [n, h, w]
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colors (List[List[Int]]): colors for predicted masks, [[r, g, b] * n]
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im_gpu (tensor): img is in cuda, shape: [3, h, w], range: [0, 1]
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alpha (float): mask transparency: 0.0 fully transparent, 1.0 opaque
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"""
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if self.pil:
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# convert to numpy first
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self.im = np.asarray(self.im).copy()
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if im_gpu is None:
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# Add multiple masks of shape(h,w,n) with colors list([r,g,b], [r,g,b], ...)
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if len(masks) == 0:
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return
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if isinstance(masks, torch.Tensor):
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masks = torch.as_tensor(masks, dtype=torch.uint8)
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masks = masks.permute(1, 2, 0).contiguous()
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masks = masks.cpu().numpy()
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# masks = np.ascontiguousarray(masks.transpose(1, 2, 0))
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masks = scale_image(masks.shape[:2], masks, self.im.shape)
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masks = np.asarray(masks, dtype=np.float32)
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colors = np.asarray(colors, dtype=np.float32) # shape(n,3)
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s = masks.sum(2, keepdims=True).clip(0, 1) # add all masks together
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masks = (masks @ colors).clip(0, 255) # (h,w,n) @ (n,3) = (h,w,3)
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self.im[:] = masks * alpha + self.im * (1 - s * alpha)
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else:
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if len(masks) == 0:
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self.im[:] = im_gpu.permute(1, 2, 0).contiguous().cpu().numpy() * 255
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colors = torch.tensor(colors, device=im_gpu.device, dtype=torch.float32) / 255.0
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colors = colors[:, None, None] # shape(n,1,1,3)
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masks = masks.unsqueeze(3) # shape(n,h,w,1)
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masks_color = masks * (colors * alpha) # shape(n,h,w,3)
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inv_alph_masks = (1 - masks * alpha).cumprod(0) # shape(n,h,w,1)
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mcs = (masks_color * inv_alph_masks).sum(0) * 2 # mask color summand shape(n,h,w,3)
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im_gpu = im_gpu.flip(dims=[0]) # flip channel
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im_gpu = im_gpu.permute(1, 2, 0).contiguous() # shape(h,w,3)
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im_gpu = im_gpu * inv_alph_masks[-1] + mcs
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im_mask = (im_gpu * 255).byte().cpu().numpy()
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# print(type(im_gpu), type(im_mask), type(self.im.shape))
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self.im[:] = scale_image(im_gpu.shape, im_mask, self.im.shape)
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if self.pil:
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# convert im back to PIL and update draw
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self.fromarray(self.im)
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def rectangle(self, xy, fill=None, outline=None, width=1):
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# Add rectangle to image (PIL-only)
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self.draw.rectangle(xy, fill, outline, width)
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def text(self, xy, text, txt_color=(255, 255, 255), anchor='top'):
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# Add text to image (PIL-only)
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if anchor == 'bottom': # start y from font bottom
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w, h = self.font.getsize(text) # text width, height
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xy[1] += 1 - h
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self.draw.text(xy, text, fill=txt_color, font=self.font)
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def fromarray(self, im):
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# Update self.im from a numpy array
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self.im = im if isinstance(im, Image.Image) else Image.fromarray(im)
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self.draw = ImageDraw.Draw(self.im)
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def result(self):
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# Return annotated image as array
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return np.asarray(self.im)
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def time_synchronized():
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# pytorch-accurate time
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if torch.cuda.is_available():
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torch.cuda.synchronize()
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return time.time()
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def is_ascii(s=''):
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# Is string composed of all ASCII (no UTF) characters? (note str().isascii() introduced in python 3.7)
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s = str(s) # convert list, tuple, None, etc. to str
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return len(s.encode().decode('ascii', 'ignore')) == len(s)
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def scale_boxes(img1_shape, boxes, img0_shape, ratio_pad=None):
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# Rescale boxes (xyxy) from img1_shape to img0_shape
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if ratio_pad is None: # calculate from img0_shape
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gain = min(img1_shape[0] / img0_shape[0], img1_shape[1] / img0_shape[1]) # gain = old / new
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pad = (img1_shape[1] - img0_shape[1] * gain) / 2, (img1_shape[0] - img0_shape[0] * gain) / 2 # wh padding
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else:
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gain = ratio_pad[0][0]
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pad = ratio_pad[1]
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boxes[..., [0, 2]] -= pad[0] # x padding
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boxes[..., [1, 3]] -= pad[1] # y padding
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boxes[..., :4] /= gain
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clip_boxes(boxes, img0_shape)
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return boxes
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def scale_segments(img1_shape, segments, img0_shape, ratio_pad=None, normalize=False):
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# Rescale coords (xyxy) from img1_shape to img0_shape
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if ratio_pad is None: # calculate from img0_shape
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gain = min(img1_shape[0] / img0_shape[0], img1_shape[1] / img0_shape[1]) # gain = old / new
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pad = (img1_shape[1] - img0_shape[1] * gain) / 2, (img1_shape[0] - img0_shape[0] * gain) / 2 # wh padding
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else:
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gain = ratio_pad[0][0]
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pad = ratio_pad[1]
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segments[:, 0] -= pad[0] # x padding
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segments[:, 1] -= pad[1] # y padding
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segments /= gain
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clip_segments(segments, img0_shape)
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if normalize:
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segments[:, 0] /= img0_shape[1] # width
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segments[:, 1] /= img0_shape[0] # height
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return segments
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def clip_boxes(boxes, shape):
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# Clip boxes (xyxy) to image shape (height, width)
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if isinstance(boxes, torch.Tensor): # faster individually
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boxes[..., 0].clamp_(0, shape[1]) # x1
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boxes[..., 1].clamp_(0, shape[0]) # y1
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boxes[..., 2].clamp_(0, shape[1]) # x2
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boxes[..., 3].clamp_(0, shape[0]) # y2
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else: # np.array (faster grouped)
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boxes[..., [0, 2]] = boxes[..., [0, 2]].clip(0, shape[1]) # x1, x2
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boxes[..., [1, 3]] = boxes[..., [1, 3]].clip(0, shape[0]) # y1, y2
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def clip_segments(segments, shape):
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# Clip segments (xy1,xy2,...) to image shape (height, width)
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if isinstance(segments, torch.Tensor): # faster individually
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segments[:, 0].clamp_(0, shape[1]) # x
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segments[:, 1].clamp_(0, shape[0]) # y
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else: # np.array (faster grouped)
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segments[:, 0] = segments[:, 0].clip(0, shape[1]) # x
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segments[:, 1] = segments[:, 1].clip(0, shape[0]) # y
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def masks2segments(masks, strategy='largest'):
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# Convert masks(n,160,160) into segments(n,xy)
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segments = []
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for x in masks.int().cpu().numpy().astype('uint8'):
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c = cv2.findContours(x, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)[0]
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if c:
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if strategy == 'concat': # concatenate all segments
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c = np.concatenate([x.reshape(-1, 2) for x in c])
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elif strategy == 'largest': # select largest segment
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c = np.array(c[np.array([len(x) for x in c]).argmax()]).reshape(-1, 2)
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else:
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c = np.zeros((0, 2)) # no segments found
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segments.append(c.astype('float32'))
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return segments
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def process_mask(protos, masks_in, bboxes, shape, upsample=False):
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"""
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Crop before upsample.
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proto_out: [mask_dim, mask_h, mask_w]
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out_masks: [n, mask_dim], n is number of masks after nms
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bboxes: [n, 4], n is number of masks after nms
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shape:input_image_size, (h, w)
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return: h, w, n
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"""
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c, mh, mw = protos.shape # CHW
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ih, iw = shape
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# print(masks_in.shape, protos.shape)
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masks = (masks_in @ protos.float().view(c, -1)).sigmoid().view(-1, mh, mw) # CHW
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downsampled_bboxes = bboxes.clone()
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downsampled_bboxes[:, 0] *= mw / iw
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downsampled_bboxes[:, 2] *= mw / iw
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downsampled_bboxes[:, 3] *= mh / ih
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downsampled_bboxes[:, 1] *= mh / ih
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masks = crop_mask(masks, downsampled_bboxes) # CHW
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if upsample:
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masks = F.interpolate(masks[None], shape, mode='bilinear', align_corners=False)[0] # CHW
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return masks.gt_(0.5)
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def crop_mask(masks, boxes):
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"""
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"Crop" predicted masks by zeroing out everything not in the predicted bbox.
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Vectorized by Chong (thanks Chong).
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Args:
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- masks should be a size [h, w, n] tensor of masks
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- boxes should be a size [n, 4] tensor of bbox coords in relative point form
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"""
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n, h, w = masks.shape
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x1, y1, x2, y2 = torch.chunk(boxes[:, :, None], 4, 1) # x1 shape(1,1,n)
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r = torch.arange(w, device=masks.device, dtype=x1.dtype)[None, None, :] # rows shape(1,w,1)
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c = torch.arange(h, device=masks.device, dtype=x1.dtype)[None, :, None] # cols shape(h,1,1)
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return masks * ((r >= x1) * (r < x2) * (c >= y1) * (c < y2))
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def scale_image(im1_shape, masks, im0_shape, ratio_pad=None):
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"""
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img1_shape: model input shape, [h, w]
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img0_shape: origin pic shape, [h, w, 3]
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masks: [h, w, num]
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"""
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# Rescale coordinates (xyxy) from im1_shape to im0_shape
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if ratio_pad is None: # calculate from im0_shape
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gain = min(im1_shape[0] / im0_shape[0], im1_shape[1] / im0_shape[1]) # gain = old / new
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pad = (im1_shape[1] - im0_shape[1] * gain) / 2, (im1_shape[0] - im0_shape[0] * gain) / 2 # wh padding
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else:
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pad = ratio_pad[1]
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top, left = int(pad[1]), int(pad[0]) # y, x
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bottom, right = int(im1_shape[0] - pad[1]), int(im1_shape[1] - pad[0])
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if len(masks.shape) < 2:
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raise ValueError(f'"len of masks shape" should be 2 or 3, but got {len(masks.shape)}')
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masks = masks[top:bottom, left:right]
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# masks = masks.permute(2, 0, 1).contiguous()
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# masks = F.interpolate(masks[None], im0_shape[:2], mode='bilinear', align_corners=False)[0]
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# masks = masks.permute(1, 2, 0).contiguous()
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masks = cv2.resize(masks, (im0_shape[1], im0_shape[0]))
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if len(masks.shape) == 2:
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masks = masks[:, :, None]
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return masks
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def xywh2xyxy(x):
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# Convert nx4 boxes from [x, y, w, h] to [x1, y1, x2, y2] where xy1=top-left, xy2=bottom-right
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y = x.clone() if isinstance(x, torch.Tensor) else np.copy(x)
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y[:, 0] = x[:, 0] - x[:, 2] / 2 # top left x
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y[:, 1] = x[:, 1] - x[:, 3] / 2 # top left y
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y[:, 2] = x[:, 0] + x[:, 2] / 2 # bottom right x
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y[:, 3] = x[:, 1] + x[:, 3] / 2 # bottom right y
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return y
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def non_max_suppression(
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prediction,
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conf_thres=0.25,
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iou_thres=0.45,
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classes=None,
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agnostic=False,
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multi_label=False,
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labels=(),
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max_det=300,
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nm=0, # number of masks
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):
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"""Non-Maximum Suppression (NMS) on inference results to reject overlapping detections
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Returns:
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list of detections, on (n,6) tensor per image [xyxy, conf, cls]
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"""
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if isinstance(prediction, (list, tuple)): # YOLOv5 model in validation model, output = (inference_out, loss_out)
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prediction = prediction[0] # select only inference output
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device = prediction.device
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mps = 'mps' in device.type # Apple MPS
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if mps: # MPS not fully supported yet, convert tensors to CPU labelme_dataset NMS
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prediction = prediction.cpu()
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bs = prediction.shape[0] # batch size
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nc = prediction.shape[2] - nm - 5 # number of classes
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xc = prediction[..., 4] > conf_thres # candidates
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# Checks
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assert 0 <= conf_thres <= 1, f'Invalid Confidence threshold {conf_thres}, valid values are between 0.0 and 1.0'
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assert 0 <= iou_thres <= 1, f'Invalid IoU {iou_thres}, valid values are between 0.0 and 1.0'
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# Settings
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# min_wh = 2 # (pixels) minimum box width and height
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max_wh = 7680 # (pixels) maximum box width and height
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max_nms = 30000 # maximum number of boxes into torchvision.ops.nms()
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time_limit = 0.5 + 0.05 * bs # seconds to quit after
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redundant = True # require redundant detections
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multi_label &= nc > 1 # multiple labels per box (adds 0.5ms/img)
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merge = False # use merge-NMS
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t = time.time()
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mi = 5 + nc # mask start index
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output = [torch.zeros((0, 6 + nm), device=prediction.device)] * bs
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for xi, x in enumerate(prediction): # image index, image inference
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# Apply constraints
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# x[((x[..., 2:4] < min_wh) | (x[..., 2:4] > max_wh)).any(1), 4] = 0 # width-height
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x = x[xc[xi]] # confidence
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|
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# Cat apriori labels if autolabelling
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if labels and len(labels[xi]):
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lb = labels[xi]
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v = torch.zeros((len(lb), nc + nm + 5), device=x.device)
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v[:, :4] = lb[:, 1:5] # box
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v[:, 4] = 1.0 # conf
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v[range(len(lb)), lb[:, 0].long() + 5] = 1.0 # cls
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x = torch.cat((x, v), 0)
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|
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# If none remain process next image
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if not x.shape[0]:
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continue
|
|
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# Compute conf
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x[:, 5:] *= x[:, 4:5] # conf = obj_conf * cls_conf
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|
|
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# Box/Mask
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box = xywh2xyxy(x[:, :4]) # center_x, center_y, width, height) to (x1, y1, x2, y2)
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mask = x[:, mi:] # zero columns if no masks
|
|
|
|
# Detections matrix nx6 (xyxy, conf, cls)
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|
if multi_label:
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|
i, j = (x[:, 5:mi] > conf_thres).nonzero(as_tuple=False).T
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x = torch.cat((box[i], x[i, 5 + j, None], j[:, None].float(), mask[i]), 1)
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else: # best class only
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|
conf, j = x[:, 5:mi].max(1, keepdim=True)
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|
x = torch.cat((box, conf, j.float(), mask), 1)[conf.view(-1) > conf_thres]
|
|
|
|
# Filter by class
|
|
if classes is not None:
|
|
x = x[(x[:, 5:6] == torch.tensor(classes, device=x.device)).any(1)]
|
|
|
|
# Apply finite constraint
|
|
# if not torch.isfinite(x).all():
|
|
# x = x[torch.isfinite(x).all(1)]
|
|
|
|
# Check shape
|
|
n = x.shape[0] # number of boxes
|
|
if not n: # no boxes
|
|
continue
|
|
elif n > max_nms: # excess boxes
|
|
x = x[x[:, 4].argsort(descending=True)[:max_nms]] # sort by confidence
|
|
else:
|
|
x = x[x[:, 4].argsort(descending=True)] # sort by confidence
|
|
|
|
# Batched NMS
|
|
c = x[:, 5:6] * (0 if agnostic else max_wh) # classes
|
|
boxes, scores = x[:, :4] + c, x[:, 4] # boxes (offset by class), scores
|
|
i = torchvision.ops.nms(boxes, scores, iou_thres) # NMS
|
|
if i.shape[0] > max_det: # limit detections
|
|
i = i[:max_det]
|
|
if merge and (1 < n < 3E3): # Merge NMS (boxes merged using weighted mean)
|
|
# update boxes as boxes(i,4) = weights(i,n) * boxes(n,4)
|
|
iou = box_iou(boxes[i], boxes) > iou_thres # iou matrix
|
|
weights = iou * scores[None] # box weights
|
|
x[i, :4] = torch.mm(weights, x[:, :4]).float() / weights.sum(1, keepdim=True) # merged boxes
|
|
if redundant:
|
|
i = i[iou.sum(1) > 1] # require redundancy
|
|
|
|
output[xi] = x[i]
|
|
if mps:
|
|
output[xi] = output[xi].to(device)
|
|
|
|
|
|
return output
|
|
|
|
|
|
def box_iou(box1, box2, eps=1e-7):
|
|
# https://github.com/pytorch/vision/blob/master/torchvision/ops/boxes.py
|
|
"""
|
|
Return intersection-over-union (Jaccard index) of boxes.
|
|
Both sets of boxes are expected to be in (x1, y1, x2, y2) format.
|
|
Arguments:
|
|
box1 (Tensor[N, 4])
|
|
box2 (Tensor[M, 4])
|
|
Returns:
|
|
iou (Tensor[N, M]): the NxM matrix containing the pairwise
|
|
IoU values for every element in boxes1 and boxes2
|
|
"""
|
|
|
|
# inter(N,M) = (rb(N,M,2) - lt(N,M,2)).clamp(0).prod(2)
|
|
(a1, a2), (b1, b2) = box1.unsqueeze(1).chunk(2, 2), box2.unsqueeze(0).chunk(2, 2)
|
|
inter = (torch.min(a2, b2) - torch.max(a1, b1)).clamp(0).prod(2)
|
|
|
|
# IoU = inter / (area1 + area2 - inter)
|
|
return inter / ((a2 - a1).prod(2) + (b2 - b1).prod(2) - inter + eps) |