Update app.py

app.py

@@ -1,7 +1,6 @@
 import os
 import tempfile
 import logging
-import subprocess
 from typing import List
 
 import gradio as gr
@@ -10,55 +9,18 @@ from PIL import Image
 from pdf2image import convert_from_path, convert_from_bytes
 from pdf2image.exceptions import PDFInfoNotInstalledError, PDFPageCountError
 
-# --- Logging Configuration ---
 logging.basicConfig(level=logging.INFO, format="%(asctime)s - %(levelname)s - %(message)s")
 logger = logging.getLogger(__name__)
 
-
-def check_poppler():
-    """
-    Checks if the Poppler PDF rendering utility is installed and accessible.
-    """
-    try:
-        # Run a simple poppler command to check for its existence and version
-        result = subprocess.run(["pdftoppm", "-v"], capture_output=True, text=True, check=False)
-        if result.returncode == 0 or "pdftoppm version" in result.stderr:
-            logger.info("Poppler check successful.")
-            return True
-        else:
-            logger.error(f"Poppler check failed. stderr: {result.stderr.strip()}")
-            return False
-    except FileNotFoundError:
-        logger.error("Poppler (pdftoppm command) not found. Ensure poppler-utils is installed and in the system's PATH.")
-        return False
-    except Exception as e:
-        logger.error(f"An unexpected error occurred during Poppler check: {e}")
-        return False
-
-
 def stitch_images_vertically(images: List[Image.Image]) -> Image.Image:
-    """
-    Stitches a list of PIL Images together vertically.
-
-    Args:
-        images: A list of PIL Image objects.
-
-    Returns:
-        A single PIL Image object containing all input images stitched together.
-    """
     if not images:
         return None
 
-    # Find the maximum width among all images to use as the canvas width
     max_width = max(img.width for img in images)
-    
-    # Calculate the total height by summing the height of all images
     total_height = sum(img.height for img in images)
 
-    # Create a new blank image (canvas) with a white background
     stitched_image = Image.new('RGB', (max_width, total_height), (255, 255, 255))
 
-    # Paste each image onto the canvas, one below the other
     current_y = 0
     for img in images:
         stitched_image.paste(img, (0, current_y))
@@ -66,28 +28,20 @@ def stitch_images_vertically(images: List[Image.Image]) -> Image.Image:
         
     return stitched_image
 
-
 def process_pdf(pdf_file, pdf_url, progress=gr.Progress()):
-    """
-    The main processing function for the Gradio interface.
-    It takes a PDF (either as an uploaded file or a URL), converts all its
-    pages to images, and stitches them into a single tall image.
-    """
     pdf_input_source = None
     is_bytes = False
-    source_name = "document" # Default name for output file
+    source_name = "document"
 
-    # --- 1. Determine Input Source ---
     progress(0, desc="Validating input...")
     if pdf_file is not None:
         logger.info(f"Processing uploaded file: {pdf_file.name}")
-        pdf_input_source = pdf_file.name  # .name provides the temp path in Gradio
+        pdf_input_source = pdf_file.name
         source_name = os.path.splitext(os.path.basename(pdf_file.name))[0]
-        is_bytes = False
     elif pdf_url and pdf_url.strip():
         url = pdf_url.strip()
         logger.info(f"Processing file from URL: {url}")
-        progress(0.1, desc=f"Downloading PDF from URL...")
+        progress(0.1, desc="Downloading PDF from URL...")
         try:
             response = requests.get(url, timeout=45)
             response.raise_for_status()
@@ -99,7 +53,6 @@ def process_pdf(pdf_file, pdf_url, progress=gr.Progress()):
     else:
         raise gr.Error("Please upload a PDF file or provide a valid URL.")
 
-    # --- 2. Convert PDF to a List of Images ---
     progress(0.3, desc="Converting PDF pages to images...")
     try:
         if is_bytes:
@@ -107,7 +60,7 @@ def process_pdf(pdf_file, pdf_url, progress=gr.Progress()):
         else:
             images = convert_from_path(pdf_input_source, dpi=200)
     except (PDFInfoNotInstalledError, FileNotFoundError):
-        raise gr.Error("Poppler not found. Please ensure poppler-utils is installed and in your system's PATH.")
+        raise gr.Error("Server configuration error: Poppler dependency is missing.")
     except (PDFPageCountError, Exception) as e:
         raise gr.Error(f"Failed to process the PDF. It might be corrupted or password-protected. Error: {e}")
 
@@ -116,7 +69,6 @@ def process_pdf(pdf_file, pdf_url, progress=gr.Progress()):
     
     logger.info(f"Successfully converted {len(images)} pages to images.")
 
-    # --- 3. Stitch the Images Together ---
     progress(0.7, desc=f"Stitching {len(images)} images together...")
     
     stitched_image = stitch_images_vertically(images)
@@ -125,10 +77,8 @@ def process_pdf(pdf_file, pdf_url, progress=gr.Progress()):
         
     logger.info("Image stitching complete.")
 
-    # --- 4. Save the Final Image to a Temporary File ---
     progress(0.9, desc="Saving final image...")
     
-    # Use a named temporary file that Gradio can serve
     with tempfile.NamedTemporaryFile(delete=False, suffix=".png", prefix=f"{source_name}_stitched_") as tmp_file:
         stitched_image.save(tmp_file.name, "PNG")
         output_path = tmp_file.name
@@ -136,12 +86,8 @@ def process_pdf(pdf_file, pdf_url, progress=gr.Progress()):
     logger.info(f"Final image saved to temporary path: {output_path}")
     progress(1, desc="Done!")
     
-    # --- 5. Return the path for the Gradio output components ---
-    # The first path is for the gr.Image preview, the second for the gr.File download.
     return output_path, output_path
 
-
-# --- Gradio Interface Definition ---
 with gr.Blocks(theme=gr.themes.Soft()) as demo:
     gr.Markdown(
         """
@@ -170,14 +116,13 @@ with gr.Blocks(theme=gr.themes.Soft()) as demo:
                 label="Stitched Image Preview",
                 type="filepath",
                 interactive=False,
-                height=600, # Set a fixed height for the preview area
+                height=600,
             )
             output_image_download = gr.File(
                 label="Download Stitched Image",
                 interactive=False
             )
 
-    # Connect the button click event to the processing function
     submit_btn.click(
         fn=process_pdf,
         inputs=[pdf_file_input, pdf_url_input],
@@ -186,23 +131,13 @@ with gr.Blocks(theme=gr.themes.Soft()) as demo:
 
     gr.Examples(
         examples=[
-            [None, "https://arxiv.org/pdf/1706.03762.pdf"], # "Attention is All You Need" paper
-            [None, "https://bitcoin.org/bitcoin.pdf"],     # Bitcoin whitepaper
+            [None, "https://arxiv.org/pdf/1706.03762.pdf"],
+            [None, "https://bitcoin.org/bitcoin.pdf"],
         ],
         inputs=[pdf_file_input, pdf_url_input],
         outputs=[output_image_preview, output_image_download],
         fn=process_pdf,
-        cache_examples=False # Cache results for faster demo
+        cache_examples=True
     )
 
-
-# --- Main Execution ---
-if __name__ == '__main__':
-    # Perform a check for Poppler when the script starts
-    if not check_poppler():
-        logger.warning(
-            "Poppler utilities could not be verified. The application may fail to process PDFs."
-        )
-    
-    # Launch the Gradio application
-    demo.launch(server_name="0.0.0.0", server_port=7860)
+demo.launch()