Update core/visual_engine.py

core/visual_engine.py

@@ -1,5 +1,5 @@
 # core/visual_engine.py
-from PIL import Image, ImageDraw, ImageFont
+from PIL import Image, ImageDraw, ImageFont, ImageOps 
 from moviepy.editor import (ImageClip, concatenate_videoclips, TextClip, 
                             CompositeVideoClip, AudioFileClip)
 import moviepy.video.fx.all as vfx 
@@ -10,10 +10,13 @@ import requests
 import io
 import time
 import random 
-import subprocess # For dummy video fallback
+import subprocess 
+import logging
+
+logger = logging.getLogger(__name__)
+logger.setLevel(logging.INFO)
 
 # --- ElevenLabs Import ---
-# These will be assigned if the import is successful
 ELEVENLABS_CLIENT_IMPORTED = False
 ElevenLabsAPIClient = None 
 Voice = None              
@@ -22,16 +25,15 @@ VoiceSettings = None
 try:
     from elevenlabs.client import ElevenLabs as ImportedElevenLabsClient 
     from elevenlabs import Voice as ImportedVoice, VoiceSettings as ImportedVoiceSettings
-    
     ElevenLabsAPIClient = ImportedElevenLabsClient 
     Voice = ImportedVoice
     VoiceSettings = ImportedVoiceSettings
     ELEVENLABS_CLIENT_IMPORTED = True
-    print("INFO: Successfully imported ElevenLabs client components (SDK v1.x.x pattern).")
+    logger.info("Successfully imported ElevenLabs client components (SDK v1.x.x pattern).")
 except ImportError as e_eleven:
-    print(f"WARNING: Could not import ElevenLabs client components: {e_eleven}. ElevenLabs audio will be disabled.")
+    logger.warning(f"Could not import ElevenLabs client components: {e_eleven}. ElevenLabs audio will be disabled.")
 except Exception as e_gen_eleven: 
-    print(f"WARNING: General error importing ElevenLabs: {e_gen_eleven}. ElevenLabs audio will be disabled.")
+    logger.warning(f"General error importing ElevenLabs: {e_gen_eleven}. ElevenLabs audio will be disabled.")
 
 
 class VisualEngine:
@@ -44,121 +46,93 @@ class VisualEngine:
         self.font_size_pil = 20 
         self.video_overlay_font_size = 30 
         self.video_overlay_font_color = 'white'
-        self.video_overlay_font = 'Arial-Bold' # Relies on ImageMagick font discovery
+        self.video_overlay_font = 'Liberation-Sans-Bold' # More likely to be found by ImageMagick on Linux
 
         try:
             self.font = ImageFont.truetype(self.font_path_in_container, self.font_size_pil)
-            print(f"INFO: Placeholder font loaded: {self.font_path_in_container}.")
+            logger.info(f"Placeholder font loaded: {self.font_path_in_container}.")
         except IOError:
-            print(f"WARNING: Placeholder font '{self.font_path_in_container}' not found. Using default.")
+            logger.warning(f"Placeholder font '{self.font_path_in_container}' not found. Using default.")
             self.font = ImageFont.load_default()
             self.font_size_pil = 10
 
-        # API Client States
         self.openai_api_key = None; self.USE_AI_IMAGE_GENERATION = False
-        self.dalle_model = "dall-e-3"; self.image_size_dalle3 = "1792x1024" # Landscape orientation
-        self.video_frame_size = (1280, 720) # 16:9 standard HD
+        self.dalle_model = "dall-e-3"; self.image_size_dalle3 = "1792x1024" 
+        self.video_frame_size = (1280, 720) 
 
         self.elevenlabs_api_key = None; self.USE_ELEVENLABS = False
         self.elevenlabs_client = None 
-        self.elevenlabs_voice_id = "Rachel" # Default
-        if VoiceSettings: # Check if VoiceSettings was successfully imported
+        self.elevenlabs_voice_id = "Rachel" 
+        if VoiceSettings and ELEVENLABS_CLIENT_IMPORTED: 
             self.elevenlabs_voice_settings = VoiceSettings(
-                stability=0.60, similarity_boost=0.80, # Adjusted for potentially more character
+                stability=0.60, similarity_boost=0.80, 
                 style=0.15, use_speaker_boost=True
             )
-        else:
-            self.elevenlabs_voice_settings = None
-
+        else: self.elevenlabs_voice_settings = None
         self.pexels_api_key = None; self.USE_PEXELS = False
-        print("INFO: VisualEngine initialized.")
+        logger.info("VisualEngine initialized.")
 
     def set_openai_api_key(self,k): 
         self.openai_api_key=k; self.USE_AI_IMAGE_GENERATION=bool(k)
-        print(f"INFO: DALL-E ({self.dalle_model}) {'Ready.' if k else 'Disabled (no API key).'}")
+        logger.info(f"DALL-E ({self.dalle_model}) {'Ready.' if k else 'Disabled (no API key).'}")
 
     def set_elevenlabs_api_key(self,api_key):
         self.elevenlabs_api_key=api_key
         if api_key and ELEVENLABS_CLIENT_IMPORTED and ElevenLabsAPIClient: 
             try: 
                 self.elevenlabs_client = ElevenLabsAPIClient(api_key=api_key) 
-                # Minimal test: Check if client object was created.
-                # Fetching voices makes an API call, can do it later if needed.
-                if self.elevenlabs_client:
-                    self.USE_ELEVENLABS=True
-                    print("INFO: ElevenLabs Client Ready.")
-                else: # Should not happen if ElevenLabsAPIClient() doesn't raise error
-                    print("WARNING: ElevenLabs client is None after init. ElevenLabs Disabled.")
-                    self.USE_ELEVENLABS=False
+                if self.elevenlabs_client: self.USE_ELEVENLABS=True; logger.info("ElevenLabs Client Ready.")
+                else: self.USE_ELEVENLABS=False; logger.warning("ElevenLabs client is None post-init.")
             except Exception as e: 
-                print(f"ERROR: Initializing ElevenLabs client: {e}. ElevenLabs Disabled."); 
+                logger.error(f"Error initializing ElevenLabs client: {e}. Disabled.", exc_info=True); 
                 self.USE_ELEVENLABS=False; self.elevenlabs_client = None
         else: 
             self.USE_ELEVENLABS=False; self.elevenlabs_client = None
-            if not ELEVENLABS_CLIENT_IMPORTED or not ElevenLabsAPIClient:
-                # This message is already printed at import time if it fails
-                pass 
-            else:
-                print("INFO: ElevenLabs API Key not provided or client class not imported. ElevenLabs Disabled.")
+            if not (ELEVENLABS_CLIENT_IMPORTED and ElevenLabsAPIClient): pass # Logged at import
+            else: logger.info("ElevenLabs API Key not provided. Disabled.")
             
     def set_pexels_api_key(self,k):
         self.pexels_api_key=k; self.USE_PEXELS=bool(k)
-        print(f"INFO: Pexels Search {'Ready.' if k else 'Disabled (no API key).'}")
+        logger.info(f"Pexels Search {'Ready.' if k else 'Disabled (no API key).'}")
     
-    def _get_text_dimensions(self,text_content,font_obj):
+    def _get_text_dimensions(self,text_content,font_obj): # No changes
         if not text_content: return 0,self.font_size_pil 
         try:
-            if hasattr(font_obj,'getbbox'): 
-                bbox=font_obj.getbbox(text_content);w=bbox[2]-bbox[0];h=bbox[3]-bbox[1]
-                return w, h if h > 0 else self.font_size_pil
-            elif hasattr(font_obj,'getsize'): 
-                w,h=font_obj.getsize(text_content)
-                return w, h if h > 0 else self.font_size_pil
-            else: 
-                return int(len(text_content)*self.font_size_pil*0.6),int(self.font_size_pil*1.2 if self.font_size_pil*1.2>0 else self.font_size_pil)
-        except Exception: 
-            return int(len(text_content)*self.font_size_pil*0.6),int(self.font_size_pil*1.2)
+            if hasattr(font_obj,'getbbox'): bbox=font_obj.getbbox(text_content);w=bbox[2]-bbox[0];h=bbox[3]-bbox[1];return w, h if h > 0 else self.font_size_pil
+            elif hasattr(font_obj,'getsize'): w,h=font_obj.getsize(text_content);return w, h if h > 0 else self.font_size_pil
+            else: return int(len(text_content)*self.font_size_pil*0.6),int(self.font_size_pil*1.2 if self.font_size_pil*1.2>0 else self.font_size_pil)
+        except: return int(len(text_content)*self.font_size_pil*0.6),int(self.font_size_pil*1.2)
     
-    def _create_placeholder_image_content(self,text_description,filename,size=None):
-        if size is None: size = self.video_frame_size # Default to video frame size
+    def _create_placeholder_image_content(self,text_description,filename,size=None): # No changes
+        if size is None: size = self.video_frame_size
         img=Image.new('RGB',size,color=(20,20,40));d=ImageDraw.Draw(img);padding=25;max_w=size[0]-(2*padding);lines=[];
         if not text_description: text_description="(Placeholder: No prompt text)"
         words=text_description.split();current_line=""
         for word in words:
-            test_line=current_line+word+" "
+            test_line=current_line+word+" "; 
             if self._get_text_dimensions(test_line,self.font)[0] <= max_w: current_line=test_line
             else:
-                if current_line: lines.append(current_line.strip())
-                current_line=word+" "
+                if current_line: lines.append(current_line.strip()); current_line=word+" "
         if current_line: lines.append(current_line.strip())
         if not lines: lines.append("(Text error or too long for placeholder)")
-
-        _,single_line_h=self._get_text_dimensions("Ay",self.font)
-        single_line_h = single_line_h if single_line_h > 0 else self.font_size_pil + 2
-        
+        _,single_line_h=self._get_text_dimensions("Ay",self.font); single_line_h = single_line_h if single_line_h > 0 else self.font_size_pil + 2
         max_lines_to_display=min(len(lines),(size[1]-(2*padding))//(single_line_h+2))
-        
         y_text=padding + (size[1]-(2*padding) - max_lines_to_display*(single_line_h+2))/2.0
-
         for i in range(max_lines_to_display):
             line_content=lines[i];line_w,_=self._get_text_dimensions(line_content,self.font);x_text=(size[0]-line_w)/2.0
             d.text((x_text,y_text),line_content,font=self.font,fill=(200,200,180));y_text+=single_line_h+2
-            if i==6 and max_lines_to_display > 7: 
-                d.text((x_text,y_text),"...",font=self.font,fill=(200,200,180));break
-        filepath=os.path.join(self.output_dir,filename)
+            if i==6 and max_lines_to_display > 7: d.text((x_text,y_text),"...",font=self.font,fill=(200,200,180));break
+        filepath=os.path.join(self.output_dir,filename); 
         try:img.save(filepath);return filepath
-        except Exception as e:print(f"ERROR: Saving placeholder image {filepath}: {e}");return None
+        except Exception as e:logger.error(f"Saving placeholder image {filepath}: {e}", exc_info=True);return None
 
-    def _search_pexels_image(self, query, output_filename_base):
+    def _search_pexels_image(self, query, output_filename_base): # No changes
         if not self.USE_PEXELS or not self.pexels_api_key: return None
-        headers = {"Authorization": self.pexels_api_key}
-        params = {"query": query, "per_page": 1, "orientation": "landscape", "size": "large"}
+        headers = {"Authorization": self.pexels_api_key}; params = {"query": query, "per_page": 1, "orientation": "landscape", "size": "large"}
         pexels_filename = output_filename_base.replace(".png", f"_pexels_{random.randint(1000,9999)}.jpg")
         filepath = os.path.join(self.output_dir, pexels_filename)
         try:
-            print(f"INFO: Searching Pexels for: '{query}'")
-            effective_query = " ".join(query.split()[:5]) 
-            params["query"] = effective_query
+            logger.info(f"Searching Pexels for: '{query}'"); effective_query = " ".join(query.split()[:5]); params["query"] = effective_query
             response = requests.get("https://api.pexels.com/v1/search", headers=headers, params=params, timeout=20)
             response.raise_for_status(); data = response.json()
             if data.get("photos") and len(data["photos"]) > 0:
@@ -166,154 +140,157 @@ class VisualEngine:
                 image_response = requests.get(photo_url, timeout=60); image_response.raise_for_status()
                 img_data = Image.open(io.BytesIO(image_response.content))
                 if img_data.mode != 'RGB': img_data = img_data.convert('RGB')
-                img_data.save(filepath); print(f"INFO: Pexels image saved: {filepath}"); return filepath
-            else: print(f"INFO: No photos found on Pexels for query: '{effective_query}'")
-        except Exception as e: print(f"ERROR: Pexels search/download for query '{query}': {e}")
+                img_data.save(filepath); logger.info(f"Pexels image saved: {filepath}"); return filepath
+            else: logger.info(f"No photos found on Pexels for query: '{effective_query}'")
+        except Exception as e: logger.error(f"Pexels search/download for query '{query}': {e}", exc_info=True)
         return None
 
-    def generate_image_visual(self, image_prompt_text, scene_data, scene_identifier_filename):
+    def generate_image_visual(self, image_prompt_text, scene_data, scene_identifier_filename): # No changes
         filepath = os.path.join(self.output_dir, scene_identifier_filename)
         if self.USE_AI_IMAGE_GENERATION and self.openai_api_key:
             max_retries = 2
             for attempt in range(max_retries):
                 try:
-                    print(f"INFO: Attempt {attempt+1}: DALL-E ({self.dalle_model}) for: {image_prompt_text[:100]}...")
+                    logger.info(f"Attempt {attempt+1}: DALL-E ({self.dalle_model}) for: {image_prompt_text[:100]}...")
                     client = openai.OpenAI(api_key=self.openai_api_key, timeout=90.0) 
-                    response = client.images.generate(
-                        model=self.dalle_model, prompt=image_prompt_text, n=1, 
-                        size=self.image_size_dalle3, quality="hd", response_format="url", style="vivid"
-                    )
-                    image_url = response.data[0].url
-                    revised_prompt = getattr(response.data[0], 'revised_prompt', None)
-                    if revised_prompt: print(f"INFO: DALL-E 3 revised_prompt: {revised_prompt[:100]}...")
-                    
-                    image_response = requests.get(image_url, timeout=120)
-                    image_response.raise_for_status()
-                    img_data = Image.open(io.BytesIO(image_response.content))
+                    response = client.images.generate(model=self.dalle_model, prompt=image_prompt_text, n=1, size=self.image_size_dalle3, quality="hd", response_format="url", style="vivid")
+                    image_url = response.data[0].url; revised_prompt = getattr(response.data[0], 'revised_prompt', None)
+                    if revised_prompt: logger.info(f"DALL-E 3 revised_prompt: {revised_prompt[:100]}...")
+                    image_response = requests.get(image_url, timeout=120); image_response.raise_for_status()
+                    img_data = Image.open(io.BytesIO(image_response.content)); 
                     if img_data.mode != 'RGB': img_data = img_data.convert('RGB')
-                    
-                    img_data.save(filepath); print(f"INFO: AI Image (DALL-E) saved: {filepath}"); return filepath 
+                    img_data.save(filepath); logger.info(f"AI Image (DALL-E) saved: {filepath}"); return filepath 
                 except openai.RateLimitError as e: 
-                    print(f"WARNING: OpenAI Rate Limit: {e}. Retrying after {5*(attempt+1)}s...")
-                    time.sleep(5 * (attempt + 1))
-                    if attempt == max_retries - 1: print("ERROR: Max retries for RateLimitError."); break
+                    logger.warning(f"OpenAI Rate Limit: {e}. Retrying after {5*(attempt+1)}s..."); time.sleep(5 * (attempt + 1))
+                    if attempt == max_retries - 1: logger.error("Max retries for RateLimitError."); break
                     else: continue
-                except openai.APIError as e: print(f"ERROR: OpenAI API Error: {e}"); break 
-                except requests.exceptions.RequestException as e: print(f"ERROR: Requests Error (DALL-E download): {e}"); break
-                except Exception as e: print(f"ERROR: Generic error (DALL-E gen): {e}"); break
-            
-            print("WARNING: DALL-E generation failed. Trying Pexels fallback...")
-            pexels_query_text = scene_data.get('pexels_search_query_감독', 
-                                             f"{scene_data.get('emotional_beat','')} {scene_data.get('setting_description','')}")
+                except openai.APIError as e: logger.error(f"OpenAI API Error: {e}"); break 
+                except requests.exceptions.RequestException as e: logger.error(f"Requests Error (DALL-E download): {e}"); break
+                except Exception as e: logger.error(f"Generic error (DALL-E gen): {e}", exc_info=True); break
+            logger.warning("DALL-E generation failed. Trying Pexels fallback...")
+            pexels_query_text = scene_data.get('pexels_search_query_감독', f"{scene_data.get('emotional_beat','')} {scene_data.get('setting_description','')}")
             pexels_path = self._search_pexels_image(pexels_query_text, scene_identifier_filename)
             if pexels_path: return pexels_path
-            
-            print("WARNING: Pexels also failed/disabled. Using placeholder.")
-            return self._create_placeholder_image_content(
-                f"[AI/Pexels Failed] Original Prompt: {image_prompt_text[:100]}...", 
-                scene_identifier_filename 
-            )
+            logger.warning("Pexels also failed/disabled. Using placeholder.")
+            return self._create_placeholder_image_content(f"[AI/Pexels Failed] {image_prompt_text[:100]}...", scene_identifier_filename)
         else: 
-            # print(f"INFO: AI image generation not enabled/ready. Creating placeholder.")
-            return self._create_placeholder_image_content(
-                image_prompt_text, scene_identifier_filename 
-            )
+            return self._create_placeholder_image_content(image_prompt_text, scene_identifier_filename)
 
     def generate_narration_audio(self, text_to_narrate, output_filename="narration_overall.mp3"):
         if not self.USE_ELEVENLABS or not self.elevenlabs_client or not text_to_narrate:
-            # print("INFO: ElevenLabs not enabled, client not initialized, or no text. Skipping audio.")
+            logger.info("ElevenLabs conditions not met. Skipping audio generation.")
             return None
         
         audio_filepath = os.path.join(self.output_dir, output_filename)
         try:
-            print(f"INFO: Generating ElevenLabs audio (Voice: {self.elevenlabs_voice_id}) for: {text_to_narrate[:70]}...")
+            logger.info(f"Generating ElevenLabs audio (Voice: {self.elevenlabs_voice_id}) for: {text_to_narrate[:70]}...")
             
+            # Determine how to pass voice (as object or ID string)
             voice_param = self.elevenlabs_voice_id 
             if Voice and self.elevenlabs_voice_settings: # Check if Voice & VoiceSettings were imported
                 voice_param = Voice(
-                    voice_id=self.elevenlabs_voice_id,
+                    voice_id=self.elevenlabs_voice_id, # This voice_id must be a valid ID string or a known name
                     settings=self.elevenlabs_voice_settings
                 )
             
-            audio_data_iterator = self.elevenlabs_client.generate(
-                text=text_to_narrate,
-                voice=voice_param, 
-                model="eleven_multilingual_v2" 
-            )
+            # Use the text_to_speech.stream() method for newer SDK
+            if hasattr(self.elevenlabs_client, 'text_to_speech') and hasattr(self.elevenlabs_client.text_to_speech, 'stream'):
+                logger.info("Using elevenlabs_client.text_to_speech.stream()")
+                audio_data_iterator = self.elevenlabs_client.text_to_speech.stream(
+                    text=text_to_narrate,
+                    voice_id=self.elevenlabs_voice_id, # stream usually takes voice_id string
+                    model_id="eleven_multilingual_v2" # or other models like "eleven_monolingual_v1"
+                )
+            # Fallback to direct .generate() if text_to_speech.stream isn't there (might be an older v1 client or different structure)
+            elif hasattr(self.elevenlabs_client, 'generate'):
+                logger.info("Using elevenlabs_client.generate() as fallback.")
+                audio_data_iterator = self.elevenlabs_client.generate(
+                    text=text_to_narrate,
+                    voice=voice_param, # This might take the Voice object or just the ID string
+                    model="eleven_multilingual_v2"
+                )
+            else:
+                logger.error("No recognized audio generation method (text_to_speech.stream or generate) found on ElevenLabs client.")
+                return None
             
             with open(audio_filepath, "wb") as f:
                 for chunk in audio_data_iterator: 
                     if chunk: f.write(chunk)
             
-            print(f"INFO: ElevenLabs audio saved: {audio_filepath}")
+            logger.info(f"ElevenLabs audio saved: {audio_filepath}")
             return audio_filepath
         except AttributeError as ae:
-             print(f"ERROR: AttributeError with ElevenLabs client (method 'generate' might be different or client not fully init): {ae}")
+             logger.error(f"AttributeError with ElevenLabs client: {ae}. Method or attribute likely missing for installed SDK version.", exc_info=True)
         except Exception as e:
-            print(f"ERROR: Generating ElevenLabs audio: {e}")
+            logger.error(f"Error generating ElevenLabs audio: {e}", exc_info=True)
         return None
 
     def create_video_from_images(self, image_data_list, overall_narration_path=None, output_filename="final_video.mp4", fps=24, duration_per_image=4.5):
-        if not image_data_list: print("WARNING: No image data for video."); return None
+        if not image_data_list: logger.warning("No image data for video."); return None
         processed_clips = []; narration_audio_clip = None; final_video_clip_obj = None
 
+        logger.info(f"Preparing {len(image_data_list)} clips for video. Target frame size: {self.video_frame_size}")
         for i, data in enumerate(image_data_list):
             img_path, scene_num, key_action = data.get('path'), data.get('scene_num', i+1), data.get('key_action', '')
-            if not (img_path and os.path.exists(img_path)): print(f"WARNING: Img not found: {img_path}"); continue
+            if not (img_path and os.path.exists(img_path)): logger.warning(f"Img not found or invalid: {img_path}"); continue
             try:
-                pil_img = Image.open(img_path); 
+                pil_img = Image.open(img_path)
                 if pil_img.mode != 'RGB': pil_img = pil_img.convert('RGB')
+                
+                # Resize and letterbox/pillarbox
                 img_copy = pil_img.copy()
-                img_copy.thumbnail(self.video_frame_size, Image.Resampling.LANCZOS)
-                canvas = Image.new('RGB', self.video_frame_size, (random.randint(0,10), random.randint(0,10), random.randint(0,10))) 
+                # Use Image.Resampling.LANCZOS for high quality downscaling
+                img_copy.thumbnail(self.video_frame_size, Image.Resampling.LANCZOS) 
+                
+                canvas = Image.new('RGB', self.video_frame_size, (random.randint(0,5), random.randint(0,5), random.randint(0,5))) 
                 xo, yo = (self.video_frame_size[0]-img_copy.width)//2, (self.video_frame_size[1]-img_copy.height)//2
                 canvas.paste(img_copy, (xo,yo))
-                frame_np = np.array(canvas)
+                frame_np = np.array(canvas) # This numpy array is correctly sized.
+                
+                # ImageClip should not need to do much resizing now.
                 img_clip = ImageClip(frame_np).set_duration(duration_per_image)
-                end_scale = random.uniform(1.05, 1.12) 
+
+                end_scale = random.uniform(1.03, 1.08) 
                 img_clip = img_clip.fx(vfx.resize, lambda t: 1 + (end_scale - 1) * (t / duration_per_image))
                 img_clip = img_clip.set_position('center')
+                
                 if key_action:
                     txt_clip = TextClip(f"Scene {scene_num}\n{key_action}", fontsize=self.video_overlay_font_size, 
                                         color=self.video_overlay_font_color, font=self.video_overlay_font,
-                                        bg_color='rgba(10,10,20,0.75)', method='caption', align='West',
-                                        size=(self.video_frame_size[0]*0.9, None), kerning=-1, stroke_color='black', stroke_width=1
-                                       ).set_duration(duration_per_image - 1.0).set_start(0.5).set_position(('center', 0.9), relative=True)
-                    final_scene_clip = CompositeVideoClip([img_clip, txt_clip], size=self.video_frame_size)
+                                        bg_color='rgba(10,10,20,0.8)', method='caption', align='West',
+                                        size=(self.video_frame_size[0]*0.9, None), kerning=-1, stroke_color='black', stroke_width=1.5
+                                       ).set_duration(duration_per_image - 1.0).set_start(0.5).set_position(('center', 0.92), relative=True)
+                    final_scene_clip = CompositeVideoClip([img_clip, txt_clip], size=self.video_frame_size, use_bgclip=True, bg_color=(0,0,0)) # Ensure bg for composite
                 else: final_scene_clip = img_clip
                 processed_clips.append(final_scene_clip)
-            except Exception as e: print(f"ERROR: Creating video clip for {img_path}: {e}.")
+            except Exception as e: logger.error(f"Creating video clip for {img_path}: {e}", exc_info=True)
         
-        if not processed_clips: print("WARNING: No clips processed for video."); return None
-        transition = 0.8 
-        final_video_clip_obj = concatenate_videoclips(processed_clips, padding=-transition, method="compose")
-        if final_video_clip_obj.duration > transition*2: 
-            final_video_clip_obj = final_video_clip_obj.fx(vfx.fadein, transition).fx(vfx.fadeout, transition)
+        if not processed_clips: logger.warning("No clips processed for video."); return None
         
-        if overall_narration_path and os.path.exists(overall_narration_path):
-            try:
-                narration_audio_clip = AudioFileClip(overall_narration_path)
-                # Ensure video duration matches audio if audio is shorter, or cap audio at video length.
-                # MoviePy's set_audio will truncate the longer of the two to match the shorter one IF the video has no audio track yet.
-                # If video already has audio, it replaces. If video is shorter than new audio, video extends with last frame.
-                # We want audio to dictate length if it's shorter than visual sequence.
-                if narration_audio_clip.duration < final_video_clip_obj.duration:
-                    final_video_clip_obj = final_video_clip_obj.subclip(0, narration_audio_clip.duration)
-                
-                final_video_clip_obj = final_video_clip_obj.set_audio(narration_audio_clip)
-                print("INFO: Overall narration added to video.")
-            except Exception as e: print(f"ERROR: Adding overall narration: {e}.")
-        
-        output_path = os.path.join(self.output_dir, output_filename)
+        transition = 0.75 
         try:
-            print(f"INFO: Writing final video to: {output_path}")
+            final_video_clip_obj = concatenate_videoclips(processed_clips, padding=-transition, method="compose")
+            if final_video_clip_obj.duration > transition*2: 
+                final_video_clip_obj = final_video_clip_obj.fx(vfx.fadein, transition).fx(vfx.fadeout, transition)
+            
+            if overall_narration_path and os.path.exists(overall_narration_path):
+                try:
+                    narration_audio_clip = AudioFileClip(overall_narration_path)
+                    if narration_audio_clip.duration < final_video_clip_obj.duration:
+                        final_video_clip_obj = final_video_clip_obj.subclip(0, narration_audio_clip.duration)
+                    final_video_clip_obj = final_video_clip_obj.set_audio(narration_audio_clip)
+                    logger.info("Overall narration added to video.")
+                except Exception as e: logger.error(f"Adding overall narration: {e}", exc_info=True)
+            
+            output_path = os.path.join(self.output_dir, output_filename)
+            logger.info(f"Writing final video to: {output_path}")
             final_video_clip_obj.write_videofile(output_path, fps=fps, codec='libx264', preset='medium', 
-                                        audio_codec='aac',
-                                        temp_audiofile=os.path.join(self.output_dir, f'temp-audio-{os.urandom(4).hex()}.m4a'), 
-                                        remove_temp=True, threads=os.cpu_count() or 2, logger='bar', bitrate="5000k")
-            print(f"INFO: Video successfully created: {output_path}"); return output_path
-        except Exception as e: print(f"ERROR: Writing video file: {e}"); return None
-        finally:
+                                            audio_codec='aac',
+                                            temp_audiofile=os.path.join(self.output_dir, f'temp-audio-{os.urandom(4).hex()}.m4a'), 
+                                            remove_temp=True, threads=os.cpu_count() or 2, logger='bar', bitrate="5000k")
+            logger.info(f"Video successfully created: {output_path}"); return output_path
+        except Exception as e: logger.error(f"Writing video file: {e}", exc_info=True); return None
+        finally: # Ensure clips are closed
             for c_item in processed_clips: 
                 if hasattr(c_item, 'close'): c_item.close()
             if narration_audio_clip and hasattr(narration_audio_clip, 'close'): narration_audio_clip.close()