adding seuqential same_camera as well maybe bug or not

prepare_data.py

@@ -148,6 +148,8 @@ def generate_cross_camera_pairs(images_list1, images_list2):
 def generate_multi_camera_pairs(camera_images, window_size=20):
     """
     Generate image pairs across multiple cameras sequentially.
+    Also generates pairs within the same camera if only one camera is present.
+    
     :param camera_images: Dictionary of camera names to image lists
     :param window_size: Number of images to match before and after each image
     :return: List of image pair tuples with camera names
@@ -159,6 +161,7 @@ def generate_multi_camera_pairs(camera_images, window_size=20):
     for camera, images in camera_images.items():
         if len(images) < max_images:
             camera_images[camera] = images + [None] * (max_images - len(images))
+    print(camera_images)
     
     image_pairs = []
     
@@ -170,16 +173,35 @@ def generate_multi_camera_pairs(camera_images, window_size=20):
             if base_images[current_index] is None:
                 continue
             
-            # Generate pairs with images from other cameras in the same time step
+            # Generate pairs with other cameras
             for target_camera, target_images in camera_images.items():
-                if base_camera == target_camera:
+                # Skip self-pairing at the same index (would create identical pairs)
+                if base_camera == target_camera and current_index == current_index:
+                    # But still generate pairs for same camera at different timestamps
+                    # if there's only one camera
+                    if len(camera_images) == 1:
+                        # Generate pairs within window size for forward and backward directions
+                        for i in range(1, window_size + 1):
+                            # Forward window
+                            if current_index + i < max_images and base_images[current_index + i] is not None:
+                                image_pairs.append((
+                                    f"{base_camera}/{base_images[current_index]}", 
+                                    f"{base_camera}/{base_images[current_index + i]}"
+                                ))
+                            
+                            # Backward window
+                            if current_index - i >= 0 and base_images[current_index - i] is not None:
+                                image_pairs.append((
+                                    f"{base_camera}/{base_images[current_index]}", 
+                                    f"{base_camera}/{base_images[current_index - i]}"
+                                ))
                     continue
                 
                 # Skip if target image is None
                 if target_images[current_index] is None:
                     continue
                 
-                # Add current image pair
+                # Add current image pair (from different cameras)
                 image_pairs.append((f"{base_camera}/{base_images[current_index]}", 
                                     f"{target_camera}/{target_images[current_index]}"))
                 
@@ -299,10 +321,12 @@ def generate_exhaustive_pairs(folder_path, output_file_pairs_exhaustive, scene_n
 def generate_sequential_pairs(folder_path, output_file_pairs_sequential, scene_name):
     # Get images from all cameras
     camera_images = get_list_images(folder_path)
+    print(camera_images)
     
     # Generate exhaustive list of pairs of images
     print(f"Generating image pairs for scene: {scene_name}")
     images_pairs_sequential = generate_multi_camera_pairs(camera_images)
+    print(images_pairs_sequential)
 
     # Save pairs to file
     save_pairs_to_file(images_pairs_sequential, output_file_pairs_sequential, scene)