Update app.py

app.py

@@ -206,7 +206,7 @@ def download_pdf(patent_number):
 
 def preview_pdf(pdf_path, scale_factor=0.5):
     """
-    Generate and resize the first page of the PDF for a compact preview.
+    Generate and display a resized preview of the first page of the PDF.
     Args:
         pdf_path (str): Path to the PDF file.
         scale_factor (float): Factor to reduce the image size (default is 0.5).
@@ -214,23 +214,21 @@ def preview_pdf(pdf_path, scale_factor=0.5):
         str: Path to the resized image preview.
     """
     try:
-        doc = fitz.open(pdf_path)  # Open the PDF document
-        first_page = doc[0]  # Extract the first page
-        pix = first_page.get_pixmap()  # Get the pixmap (image) of the page
-
-        # Resize the image manually using width and height scaling
-        new_width = int(pix.width * scale_factor)
-        new_height = int(pix.height * scale_factor)
-        resized_pix = fitz.Pixmap(pix, 0)  # Clone the pixmap
-
-        # Manually downscale the image using `fitz.Pixmap` constructor
-        resized_pix = fitz.Pixmap(fitz.csRGB, pix, new_width, new_height)
-
-        # Save resized image temporarily
-        temp_image_path = os.path.join(tempfile.gettempdir(), "pdf_preview_resized.png")
-        resized_pix.save(temp_image_path)  # Save the resized image
+        # Open the PDF and extract the first page
+        doc = fitz.open(pdf_path)
+        first_page = doc[0]
+        
+        # Apply scaling using a transformation matrix
+        matrix = fitz.Matrix(scale_factor, scale_factor)  # Scale down the image
+        pix = first_page.get_pixmap(matrix=matrix)  # Generate scaled image
+        
+        # Save the preview image
+        temp_image_path = os.path.join(tempfile.gettempdir(), "pdf_preview.png")
+        pix.save(temp_image_path)
+        
+        doc.close()
         return temp_image_path
-
+    
     except Exception as e:
         st.error(f"Error generating PDF preview: {e}")
         return None