[training_utils] fix: allow empty image_key/video_key in rl dataset

recipe/deepeyes/deepeyes.py

@@ -78,8 +78,9 @@ def __getitem__(self, item):
             multi_modal_data = {}
 
             images = None
-            if self.image_key in row_dict and row_dict.get(self.image_key, None) is not None:
-                images = [Image.open(io.BytesIO(image["bytes"])) for image in row_dict.pop(self.image_key)]
+            row_dict_images = row_dict.pop(self.image_key, None)
+            if row_dict_images:
+                images = [Image.open(io.BytesIO(image["bytes"])) for image in row_dict_images]
 
                 # due to the image key is "image" instead of "images" in vllm, we need to use "image" here
                 # link: https://github.com/vllm-project/vllm/blob/3c545c0c3b98ee642373a308197d750d0e449403/vllm/multimodal/parse.py#L205  # noqa: E501

verl/utils/dataset/rl_dataset.py

@@ -157,8 +157,16 @@ def doc2len(doc) -> int:
                     raw_prompt = self.processor.apply_chat_template(
                         messages, add_generation_prompt=True, tokenize=False, **self.apply_chat_template_kwargs
                     )
-                    images = [process_image(image) for image in doc[image_key]] if image_key in doc else None
-                    videos = [process_video(video) for video in doc[video_key]] if video_key in doc else None
+                    images = (
+                        [process_image(image) for image in doc[image_key]]
+                        if image_key in doc and doc[image_key]
+                        else None
+                    )
+                    videos = (
+                        [process_video(video) for video in doc[video_key]]
+                        if video_key in doc and doc[video_key]
+                        else None
+                    )
 
                     return len(processor(text=[raw_prompt], images=images, videos=videos)["input_ids"][0])
 
@@ -230,16 +238,18 @@ def __getitem__(self, item):
             multi_modal_data = {}
 
             images = None
-            if self.image_key in row_dict and row_dict.get(self.image_key, None) is not None:
-                images = [process_image(image) for image in row_dict.pop(self.image_key)]
+            row_dict_images = row_dict.pop(self.image_key, None)
+            if row_dict_images:
+                images = [process_image(image) for image in row_dict_images]
 
                 # due to the image key is "image" instead of "images" in vllm, we need to use "image" here
                 # link: https://github.com/vllm-project/vllm/blob/3c545c0c3b98ee642373a308197d750d0e449403/vllm/multimodal/parse.py#L205
                 multi_modal_data["image"] = images
 
             videos = None
-            if self.video_key in row_dict and row_dict.get(self.video_key, None) is not None:
-                videos = [process_video(video) for video in row_dict.pop(self.video_key)]
+            row_dict_videos = row_dict.pop(self.video_key, None)
+            if row_dict_videos:
+                videos = [process_video(video) for video in row_dict_videos]
 
                 # due to the video key is "video" instead of "videos" in vllm, we need to use "video" here
                 # link: https://github.com/vllm-project/vllm/blob/3c545c0c3b98ee642373a308197d750d0e449403/vllm/multimodal/parse.py#L205