[VLM] fix: fix only the grids from last split mm item is collected for qwen-vl (#26094)

python/sglang/srt/multimodal/processors/qwen_vl.py

@@ -374,13 +374,12 @@ class QwenVLImageProcessor(SGLangBaseProcessor):
         return input_ids, offsets, modality_list
 
     def compute_mrope_positions(self, input_ids, mm_items):
-        image_grid_thw = None
-        video_grid_thw = None
-        for item in mm_items:
-            if "image_grid_thw" in item.model_specific_data:
-                image_grid_thw = item.model_specific_data["image_grid_thw"]
-            if "video_grid_thw" in item.model_specific_data:
-                video_grid_thw = item.model_specific_data["video_grid_thw"]
+        image_grid_thw = self._concat_mm_item_grid(
+            mm_items, "image_grid_thw", Modality.IMAGE
+        )
+        video_grid_thw = self._concat_mm_item_grid(
+            mm_items, "video_grid_thw", Modality.VIDEO
+        )
 
         input_ids_tensor = torch.tensor(input_ids, dtype=torch.long).unsqueeze(0)
         mrope_positions, mrope_position_delta = MRotaryEmbedding.get_rope_index(
@@ -529,6 +528,32 @@ class QwenVLImageProcessor(SGLangBaseProcessor):
         mrope_position_delta = (mrope_positions.max() + 1 - input_len).reshape(1, 1)
         return mrope_positions, mrope_position_delta
 
+    @classmethod
+    def _concat_mm_item_grid(cls, mm_items: list[MultimodalDataItem], key, modality):
+        grids = []
+        for item in mm_items:
+            if not item.is_modality(modality):
+                continue
+            grid = cls._as_grid_batch(item.model_specific_data.get(key))
+            if grid is not None:
+                grids.append(grid)
+        if not grids:
+            return None
+        if len(grids) == 1:
+            return grids[0]
+        return torch.cat(grids, dim=0)
+
+    @classmethod
+    def _get_grid_from_output_or_items(
+        cls, ret, mm_items, key, modality, input_data=None
+    ):
+        grid = cls._get_processor_output_value(ret, key)
+        if grid is None:
+            grid = cls._concat_mm_item_grid(mm_items, key, modality)
+        if grid is None and input_data and isinstance(input_data[0], dict):
+            grid = input_data[0].get(key)
+        return grid
+
     def get_mm_data(self, prompt, embeddings, **kwargs):
         img_grid_thw = kwargs.get("img_grid_thw", None)
         video_grid_thw = kwargs.get("video_grid_thw", None)
@@ -646,7 +671,7 @@ class QwenVLImageProcessor(SGLangBaseProcessor):
         rid = getattr(request_obj, "rid", "anonymous_rid")
 
         video_metadata = None
-        if base_output.videos:
+        if base_output.videos and not isinstance(base_output.videos[0], dict):
             videos_processed = [
                 await preprocess_video(video, video_config=self.video_config)
                 for video in base_output.videos
@@ -683,9 +708,11 @@ class QwenVLImageProcessor(SGLangBaseProcessor):
                     audio_item.feature_attention_mask, dim=1
                 )
 
-        second_per_grid_ts = getattr(ret, "second_per_grid_ts", None)
+        second_per_grid_ts = self._get_processor_output_value(ret, "second_per_grid_ts")
         if second_per_grid_ts is None:
-            second_per_grid_ts = getattr(ret, "video_second_per_grid", None)
+            second_per_grid_ts = self._get_processor_output_value(
+                ret, "video_second_per_grid"
+            )
 
         process_time = time.perf_counter()
 
@@ -712,15 +739,16 @@ class QwenVLImageProcessor(SGLangBaseProcessor):
         else:
             padded_input_ids = list(padded_input_ids)
 
-        image_grid_thw = self._get_processor_output_value(ret, "image_grid_thw")
-        if image_grid_thw is None and image_data and isinstance(image_data[0], dict):
-            image_grid_thw = image_data[0].get("image_grid_thw")
-
-        video_grid_thw = self._get_processor_output_value(ret, "video_grid_thw")
-        if video_grid_thw is None and request_obj.video_data:
-            first_video = request_obj.video_data[0]
-            if isinstance(first_video, dict):
-                video_grid_thw = first_video.get("video_grid_thw")
+        image_grid_thw = self._get_grid_from_output_or_items(
+            ret, mm_items, "image_grid_thw", Modality.IMAGE, image_data
+        )
+        video_grid_thw = self._get_grid_from_output_or_items(
+            ret,
+            mm_items,
+            "video_grid_thw",
+            Modality.VIDEO,
+            request_obj.video_data,
+        )
 
         mrope_result = self._get_precomputed_mrope_from_output(ret)
         if mrope_result is None: