Support conversations with Gemini 3 Pro Image (model "gemini-3-pro-image-preview").

Prior to this change, after the model generated an image the conversation would not be able to progress. It would stall out because we were never storing the image in context, so the model would never realize it already did the work of generating an image. We didn't run into issues with Gemini 2.5 Flash Image, because that model always followed up an image with a text message.

src/pipecat/processors/aggregators/llm_response_universal.py

@@ -24,6 +24,7 @@ from pipecat.audio.interruptions.base_interruption_strategy import BaseInterrupt
 from pipecat.audio.turn.smart_turn.base_smart_turn import SmartTurnParams
 from pipecat.audio.vad.vad_analyzer import VADParams
 from pipecat.frames.frames import (
+    AssistantImageRawFrame,
     BotStartedSpeakingFrame,
     BotStoppedSpeakingFrame,
     CancelFrame,
@@ -663,6 +664,8 @@ class LLMAssistantAggregator(LLMContextAggregator):
             await self._handle_function_call_cancel(frame)
         elif isinstance(frame, UserImageRawFrame):
             await self._handle_user_image_frame(frame)
+        elif isinstance(frame, AssistantImageRawFrame):
+            await self._handle_assistant_image_frame(frame)
         elif isinstance(frame, BotStoppedSpeakingFrame):
             await self.push_aggregation()
             await self.push_frame(frame, direction)
@@ -827,6 +830,24 @@ class LLMAssistantAggregator(LLMContextAggregator):
         await self.push_aggregation()
         await self.push_context_frame(FrameDirection.UPSTREAM)
 
+    async def _handle_assistant_image_frame(self, frame: AssistantImageRawFrame):
+        logger.debug(f"{self} Appending AssistantImageRawFrame to LLM context (size: {frame.size})")
+
+        if frame.original_jpeg:
+            await self._context.add_image_frame_message(
+                format="JPEG",
+                size=frame.size,  # Technically doesn't matter, since already encoded
+                image=frame.original_jpeg,
+                role="assistant",
+            )
+        else:
+            await self._context.add_image_frame_message(
+                format=frame.format,
+                size=frame.size,
+                image=frame.image,
+                role="assistant",
+            )
+
     async def _handle_llm_start(self, _: LLMFullResponseStartFrame):
         self._started += 1