Update app.py

app.py

@@ -299,7 +299,7 @@ from concurrent.futures import ThreadPoolExecutor, as_completed
 def handle_batch(workbook_path, fmt, w, h):
     if workbook_path is None:
         return [], None, '❌ Upload a workbook first.'
-    
+
     tmpdir = tempfile.mkdtemp()
     outdir = os.path.join(tmpdir, 'out')
     os.makedirs(outdir, exist_ok=True)
@@ -315,6 +315,7 @@ def handle_batch(workbook_path, fmt, w, h):
         shutil.rmtree(tmpdir)
         return [], None, '❌ No URLs found.'
 
+    # Prepare download tasks
     tasks = []
     for code, url, _ in jobs:
         idx = sum(1 for t in tasks if t[0] == code)
@@ -323,9 +324,8 @@ def handle_batch(workbook_path, fmt, w, h):
         dl_path = os.path.join(outdir, f"{code}{suf}{ext_in}")
         tasks.append((code, url, dl_path, suf))
 
-    # Download with tracking
+    # Download images
     future_to_task = {}
-
     with ThreadPoolExecutor(max_workers=min(32, CPU_CORES * 2)) as ex:
         for code, url, dl_path, suf in tasks:
             fut = ex.submit(download_image_fast, url, dl_path, fail_log, code, suf)
@@ -342,14 +342,19 @@ def handle_batch(workbook_path, fmt, w, h):
         if not os.path.exists(dl_path):
             continue
         try:
-            img = Image.open(dl_path)
-            final = resize_and_pad(img, max_size=w)
-            out_fn = f"{code}{suf}{'.jpg' if fmt == 'JPEG' else f'.{fmt.lower()}'}"
+            img = Image.open(dl_path).convert("RGBA")  # ensure RGBA for transparency-safe conversion
+
+            if fmt.upper() == "JPEG":
+                final = convert_to_jpeg(img, target=w)
+            else:
+                final = resize_and_pad(img.convert("RGB"), max_size=w)
+
+            out_ext = f".jpg" if fmt.upper() == "JPEG" else f".{fmt.lower()}"
+            out_fn = f"{code}{suf}{out_ext}"
             out_p = os.path.join(outdir, out_fn)
 
             if fmt.upper() == "JPEG":
-                final_jpg = convert_to_jpeg(img, target=w)
-                final_jpg.save(out_p, "JPEG", quality=95, optimize=True, progressive=True)
+                final.save(out_p, "JPEG", quality=95, optimize=True, progressive=True, subsampling=0)
             else:
                 final.save(out_p, fmt.upper())
 
@@ -358,15 +363,16 @@ def handle_batch(workbook_path, fmt, w, h):
             log_failure(fail_log, f"{code}{suf}: process error: {e}")
 
     if not processed:
-        return [], None, "⚠️ No images processed successfully"
+        shutil.rmtree(tmpdir)
+        return [], None, '❌ No images processed.'
 
-    # Zip the processed files
+    # Create ZIP of results
     zip_path = os.path.join(tmpdir, "images.zip")
     with zipfile.ZipFile(zip_path, "w", zipfile.ZIP_DEFLATED) as zipf:
-        for fpath in processed:
-            zipf.write(fpath, arcname=os.path.basename(fpath))
+        for p in processed:
+            zipf.write(p, os.path.basename(p))
 
-    return processed, zip_path, f"✅ Processed {len(processed)} images"
+    return processed, zip_path, f"✅ Processed {len(processed)} image(s)."
 
 def handle_single_upload(uploaded_file, fmt, w, h):
     if not uploaded_file: return None, None, "❌ No file."