Update app.py

app.py

@@ -3,6 +3,9 @@ import numpy as np
 import spaces
 from fastrtc import WebRTC, get_turn_credentials
 
+# This is the core processing function that will be assigned to the GPU.
+# It receives a generator (`frame_stream`) that yields frames from the webcam
+# and it yields processed frames back to the output component.
 @spaces.GPU
 def process_frames_on_gpu(frame_stream):
     """
@@ -11,6 +14,10 @@ def process_frames_on_gpu(frame_stream):
     """
     print("🚀 GPU Frame processing loop started.")
     
+    if frame_stream is None:
+        print("Input stream is None, ending.")
+        return
+
     # This loop will block until a new frame is available, making it reactive.
     for frame in frame_stream:
         if frame is not None:
@@ -26,11 +33,11 @@ def process_frames_on_gpu(frame_stream):
 with gr.Blocks(theme=gr.themes.Soft(), title="FastRTC ZeroGPU Flipper") as demo:
     gr.Markdown("# 🚀 FastRTC Webcam Flipper for ZeroGPU")
     gr.Markdown(
-        "*This version uses Gradio's native stream iterator pattern. The `process_frames_on_gpu` function is a single, decorated process that receives and yields frames, making it ideal for ZeroGPU.*"
+        "*This version uses a separate button to trigger the stream, correctly using Gradio's streaming iterator pattern for ZeroGPU without conflicting with the `fastrtc` component's internal logic.*"
     )
     
     with gr.Row():
-        with gr.Column():
+        with gr.Column(scale=1):
             gr.Markdown("### 1. Your Webcam Feed (Input)")
             webcam_input = WebRTC(
                 label="Webcam Input",
@@ -40,8 +47,9 @@ with gr.Blocks(theme=gr.themes.Soft(), title="FastRTC ZeroGPU Flipper") as demo:
                 height=480,
                 rtc_configuration=get_turn_credentials(),
             )
+            start_button = gr.Button("🚀 Start Processing Stream", variant="primary")
             
-        with gr.Column():
+        with gr.Column(scale=1):
             gr.Markdown("### 2. Flipped Video (Output)")
             video_output = WebRTC(
                 label="Flipped Output Stream",
@@ -52,13 +60,13 @@ with gr.Blocks(theme=gr.themes.Soft(), title="FastRTC ZeroGPU Flipper") as demo:
                 rtc_configuration=get_turn_credentials(),
             )
         
-    # When webcam_input is used as a streaming input, the `process_frames_on_gpu`
-    # function receives an iterator that it can loop over.
-    webcam_input.stream(
+    # By using a button's `click` event to start the stream, we use Gradio's
+    # standard streaming API, which correctly provides the iterator to our
+    # decorated function without causing a conflict.
+    start_button.click(
         fn=process_frames_on_gpu, 
         inputs=[webcam_input],
-        outputs=[video_output],
-        time_limit=120,
+        outputs=[video_output]
     )
 
 if __name__ == "__main__":