Try img2pdf to generate the pdf

Issue : Xournal can't edit ??

annotating_with_checks.py

@@ -4,6 +4,7 @@ import json
 import shutil
 import concurrent.futures
 import threading
+import img2pdf
 
 # Fix for Matplotlib in threads: Set backend to non-interactive 'Agg'
 import matplotlib
@@ -224,8 +225,17 @@ def process_student(args):
     with open(os.path.join(output_dir, "checkboxes.json"), "w") as f:
         json.dump(final_json_map, f, indent=2)
 
-    concat_img.save(os.path.join(output_dir, "Reference.png"))
-    concat_img.save(os.path.join(output_dir, "Concat.pdf"), "PDF", resolution=DPI)
+
+    # Pour éviter du drift
+    temp_img_path = os.path.join(output_dir, "Reference.jpg")
+    concat_img.save(temp_img_path, quality=90) # Save as standard image first
+    with open(os.path.join(output_dir, "Concat.pdf"), "wb") as f:
+        f.write(img2pdf.convert(temp_img_path))
+
+    # Ancien code, avec du drift
+    # concat_img.save(os.path.join(output_dir, "Concat.pdf"), "PDF", resolution=DPI)
+    # concat_img.save(os.path.join(output_dir, "Reference.png"))
+
 
 
 if __name__ == "__main__":