fix timestamp computation (was rounding fps to int...)

pipeline/process_videos.py

@@ -55,8 +55,8 @@ def process_videos() -> None:
 def get_clip_vectors(video_path, clip_wrapper):
     cap = cv2.VideoCapture(str(video_path))
     num_video_frames = int(cap.get(cv2.CAP_PROP_FRAME_COUNT))
-    fps = int(cap.get(cv2.CAP_PROP_FPS))
-    extract_every_n_frames = FRAME_EXTRACT_RATE_SECONDS * fps
+    fps = cap.get(cv2.CAP_PROP_FPS)
+    extract_every_n_frames = int(FRAME_EXTRACT_RATE_SECONDS * fps)
     for frame_idx in tqdm(range(num_video_frames), desc="Running CLIP on video"):
         ret, frame = cap.read()
         if frame_idx % extract_every_n_frames != 0: