Update streamlit_app.py

streamlit_app.py

@@ -88,97 +88,25 @@ def initialize_session_state():
     defaults = {
         'uploaded_video': None,
         'video_bytes_cache': None,
+        'video_preview_placeholder': None,
         'bg_image': None,
         'bg_image_cache': None,
         'bg_image_name': None,
+        'bg_preview_placeholder': None,
         'bg_color': "#00FF00",
         'cached_color': None,
         'color_display_cache': None,
         'processed_video_path': None,
         'processing': False,
         'progress': 0,
-        'progress_text': "Ready"
+        'progress_text': "Ready",
+        'last_video_id': None,
+        'last_bg_image_id': None
     }
     for key, value in defaults.items():
         if key not in st.session_state:
             st.session_state[key] = value
 
-# --- Video Upload Handling ---
-def handle_video_upload():
-    """Handle video file upload"""
-    uploaded = st.file_uploader(
-        "📹 Upload Video",
-        type=["mp4", "mov", "avi"],
-        key="video_uploader"
-    )
-    # Only update if actually changed
-    if uploaded is not None and uploaded != st.session_state.uploaded_video:
-        st.session_state.uploaded_video = uploaded
-        st.session_state.video_bytes_cache = None  # Clear cache when new video uploaded
-
-# --- Video Preview ---
-def show_video_preview():
-    """Show video preview in the UI"""
-    st.markdown("### Video Preview")
-    if st.session_state.uploaded_video is not None:
-        # Cache video bytes in session state to prevent reloading
-        if st.session_state.video_bytes_cache is None:
-            st.session_state.video_bytes_cache = st.session_state.uploaded_video.getvalue()
-            st.session_state.uploaded_video.seek(0)
-        st.video(st.session_state.video_bytes_cache)
-
-# --- Background Selection ---
-def handle_background_selection():
-    """Handle background selection UI"""
-    st.markdown("### Background Options")
-    bg_type = st.radio(
-        "Select Background Type:",
-        ["Image", "Color", "Blur"],
-        horizontal=True,
-        index=0,
-        key="bg_type_radio"
-    )
-    
-    if bg_type == "Image":
-        bg_image = st.file_uploader(
-            "🖼️ Upload Background Image",
-            type=["jpg", "png", "jpeg"],
-            key="bg_image_uploader"
-        )
-        # Only process if new image uploaded
-        if bg_image is not None:
-            if (st.session_state.bg_image_cache is None or 
-                st.session_state.get('bg_image_name') != bg_image.name):
-                st.session_state.bg_image = Image.open(bg_image)
-                st.session_state.bg_image_cache = st.session_state.bg_image
-                st.session_state.bg_image_name = bg_image.name
-            
-            # Display cached image
-            st.image(
-                st.session_state.bg_image_cache,
-                caption="Selected Background",
-                use_container_width=True
-            )
-    
-    elif bg_type == "Color":
-        st.session_state.bg_color = st.color_picker(
-            "🎨 Choose Background Color",
-            st.session_state.bg_color,
-            key="color_picker"
-        )
-        # Cache color display to prevent regeneration
-        if (st.session_state.color_display_cache is None or 
-            st.session_state.get('cached_color') != st.session_state.bg_color):
-            color_rgb = tuple(int(st.session_state.bg_color.lstrip('#')[i:i+2], 16) for i in (0, 2, 4))
-            color_display = np.zeros((100, 100, 3), dtype=np.uint8)
-            color_display[:, :] = color_rgb[::-1]  # RGB to BGR for OpenCV
-            st.session_state.color_display_cache = color_display
-            st.session_state.cached_color = st.session_state.bg_color
-        
-        st.image(st.session_state.color_display_cache, caption="Selected Color", width=200)
-    
-    return bg_type.lower()
-
 # --- Video Processing ---
 def process_video(input_file, background, bg_type="image"):
     """
@@ -286,15 +214,106 @@ def main():
     
     with col1:
         st.header("1. Upload Video")
-        handle_video_upload()
-        show_video_preview()
+        
+        uploaded = st.file_uploader(
+            "📹 Upload Video",
+            type=["mp4", "mov", "avi"],
+            key="video_uploader"
+        )
+        
+        # Check if video actually changed using id()
+        current_video_id = id(uploaded)
+        if current_video_id != st.session_state.last_video_id:
+            st.session_state.uploaded_video = uploaded
+            st.session_state.last_video_id = current_video_id
+            st.session_state.video_bytes_cache = None
+        
+        # Video preview section
+        st.markdown("### Video Preview")
+        if st.session_state.video_preview_placeholder is None:
+            st.session_state.video_preview_placeholder = st.empty()
+        
+        if st.session_state.uploaded_video is not None:
+            if st.session_state.video_bytes_cache is None:
+                st.session_state.video_bytes_cache = st.session_state.uploaded_video.getvalue()
+                st.session_state.uploaded_video.seek(0)
+            
+            with st.session_state.video_preview_placeholder.container():
+                st.video(st.session_state.video_bytes_cache)
+        else:
+            st.session_state.video_preview_placeholder.empty()
     
     with col2:
         st.header("2. Background Settings")
-        bg_type = handle_background_selection()
+        
+        bg_type = st.radio(
+            "Select Background Type:",
+            ["Image", "Color", "Blur"],
+            horizontal=True,
+            index=0,
+            key="bg_type_radio"
+        )
+        
+        if bg_type == "Image":
+            bg_image = st.file_uploader(
+                "🖼️ Upload Background Image",
+                type=["jpg", "png", "jpeg"],
+                key="bg_image_uploader"
+            )
+            
+            # Check if image actually changed using id()
+            current_bg_id = id(bg_image)
+            if current_bg_id != st.session_state.last_bg_image_id:
+                st.session_state.last_bg_image_id = current_bg_id
+                if bg_image is not None:
+                    st.session_state.bg_image_cache = Image.open(bg_image)
+                    st.session_state.bg_image_name = bg_image.name
+                else:
+                    st.session_state.bg_image_cache = None
+            
+            # Background preview section
+            if st.session_state.bg_preview_placeholder is None:
+                st.session_state.bg_preview_placeholder = st.empty()
+            
+            if st.session_state.bg_image_cache is not None:
+                with st.session_state.bg_preview_placeholder.container():
+                    st.image(
+                        st.session_state.bg_image_cache,
+                        caption="Selected Background",
+                        use_container_width=True
+                    )
+            else:
+                st.session_state.bg_preview_placeholder.empty()
+        
+        elif bg_type == "Color":
+            selected_color = st.color_picker(
+                "🎨 Choose Background Color",
+                st.session_state.bg_color,
+                key="color_picker"
+            )
+            
+            # Update only if color actually changed
+            if selected_color != st.session_state.cached_color:
+                st.session_state.bg_color = selected_color
+                st.session_state.cached_color = selected_color
+                
+                color_rgb = tuple(int(selected_color.lstrip('#')[i:i+2], 16) for i in (0, 2, 4))
+                color_display = np.zeros((100, 100, 3), dtype=np.uint8)
+                color_display[:, :] = color_rgb[::-1]
+                st.session_state.color_display_cache = color_display
+            
+            # Color preview section
+            if st.session_state.bg_preview_placeholder is None:
+                st.session_state.bg_preview_placeholder = st.empty()
+            
+            if st.session_state.color_display_cache is not None:
+                with st.session_state.bg_preview_placeholder.container():
+                    st.image(st.session_state.color_display_cache, caption="Selected Color", width=200)
+            else:
+                st.session_state.bg_preview_placeholder.empty()
         
         st.header("3. Process & Download")
-        # Form wrap to prevent reruns during processing
+        
         with st.form("process_form"):
             submitted = st.form_submit_button(
                 "🚀 Process Video",
@@ -306,18 +325,16 @@ def main():
                 st.session_state.processing = True
                 with st.spinner("Processing video (this may take a few minutes)..."):
                     try:
-                        # Prepare background based on type
                         background = None
                         if bg_type == "image" and st.session_state.bg_image_cache is not None:
                             background = st.session_state.bg_image_cache
                         elif bg_type == "color" and 'bg_color' in st.session_state:
                             background = st.session_state.bg_color
                         
-                        # Process the video
                         output_path = process_video(
                             st.session_state.uploaded_video,
                             background,
-                            bg_type=bg_type
+                            bg_type=bg_type.lower()
                         )
                         
                         if output_path and os.path.exists(output_path):
@@ -331,7 +348,6 @@ def main():
                     finally:
                         st.session_state.processing = False
         
-        # Show processed video if available (outside form for stability)
         if st.session_state.processed_video_path:
             st.markdown("### Processed Video")
             try:
@@ -350,6 +366,5 @@ def main():
                 st.error(f"Error displaying video: {str(e)}")
                 logger.error(f"Error displaying video: {str(e)}", exc_info=True)
 
-# --- Entry Point ---
 if __name__ == "__main__":
     main()