ultralytics 8.1.27 batched tracking fixes (#8842)

Signed-off-by: Glenn Jocher <glenn.jocher@ultralytics.com>
Co-authored-by: Glenn Jocher <glenn.jocher@ultralytics.com>

ultralytics/data/loaders.py

@@ -80,8 +80,6 @@ class LoadStreams:
         self.imgs = [[] for _ in range(n)]  # images
         self.shape = [[] for _ in range(n)]  # image shapes
         self.sources = [ops.clean_str(x) for x in sources]  # clean source names for later
-        self.info = [""] * n
-        self.is_video = [True] * n
         for i, s in enumerate(sources):  # index, source
             # Start thread to read frames from video stream
             st = f"{i + 1}/{n}: {s}... "
@@ -178,7 +176,7 @@ class LoadStreams:
                 images.append(x.pop(-1) if x else np.zeros(self.shape[i], dtype=np.uint8))
                 x.clear()
 
-        return self.sources, images, self.is_video, self.info
+        return self.sources, images, [""] * self.bs
 
     def __len__(self):
         """Return the length of the sources object."""
@@ -227,6 +225,7 @@ class LoadScreenshots:
         self.frame = 0
         self.sct = mss.mss()
         self.bs = 1
+        self.fps = 30
 
         # Parse monitor shape
         monitor = self.sct.monitors[self.screen]
@@ -246,7 +245,7 @@ class LoadScreenshots:
         s = f"screen {self.screen} (LTWH): {self.left},{self.top},{self.width},{self.height}: "
 
         self.frame += 1
-        return [str(self.screen)], [im0], [True], [s]  # screen, img, is_video, string
+        return [str(self.screen)], [im0], [s]  # screen, img, string
 
 
 class LoadImagesAndVideos:
@@ -298,6 +297,7 @@ class LoadImagesAndVideos:
 
         self.files = images + videos
         self.nf = ni + nv  # number of files
+        self.ni = ni  # number of images
         self.video_flag = [False] * ni + [True] * nv
         self.mode = "image"
         self.vid_stride = vid_stride  # video frame-rate stride
@@ -319,11 +319,11 @@ class LoadImagesAndVideos:
 
     def __next__(self):
         """Returns the next batch of images or video frames along with their paths and metadata."""
-        paths, imgs, is_video, info = [], [], [], []
+        paths, imgs, info = [], [], []
         while len(imgs) < self.bs:
             if self.count >= self.nf:  # end of file list
                 if len(imgs) > 0:
-                    return paths, imgs, is_video, info  # return last partial batch
+                    return paths, imgs, info  # return last partial batch
                 else:
                     raise StopIteration
 
@@ -344,7 +344,6 @@ class LoadImagesAndVideos:
                         self.frame += 1
                         paths.append(path)
                         imgs.append(im0)
-                        is_video.append(True)
                         info.append(f"video {self.count + 1}/{self.nf} (frame {self.frame}/{self.frames}) {path}: ")
                         if self.frame == self.frames:  # end of video
                             self.count += 1
@@ -363,16 +362,18 @@ class LoadImagesAndVideos:
                     raise FileNotFoundError(f"Image Not Found {path}")
                 paths.append(path)
                 imgs.append(im0)
-                is_video.append(False)  # no capture object for images
                 info.append(f"image {self.count + 1}/{self.nf} {path}: ")
                 self.count += 1  # move to the next file
+                if self.count >= self.ni:  # end of image list
+                    break
 
-        return paths, imgs, is_video, info
+        return paths, imgs, info
 
     def _new_video(self, path):
         """Creates a new video capture object for the given path."""
         self.frame = 0
         self.cap = cv2.VideoCapture(path)
+        self.fps = int(self.cap.get(cv2.CAP_PROP_FPS))
         if not self.cap.isOpened():
             raise FileNotFoundError(f"Failed to open video {path}")
         self.frames = int(self.cap.get(cv2.CAP_PROP_FRAME_COUNT) / self.vid_stride)
@@ -429,7 +430,7 @@ class LoadPilAndNumpy:
         if self.count == 1:  # loop only once as it's batch inference
             raise StopIteration
         self.count += 1
-        return self.paths, self.im0, [False] * self.bs, [""] * self.bs
+        return self.paths, self.im0, [""] * self.bs
 
     def __iter__(self):
         """Enables iteration for class LoadPilAndNumpy."""
@@ -494,7 +495,7 @@ class LoadTensor:
         if self.count == 1:
             raise StopIteration
         self.count += 1
-        return self.paths, self.im0, [False] * self.bs, [""] * self.bs
+        return self.paths, self.im0, [""] * self.bs
 
     def __len__(self):
         """Returns the batch size."""