diff --git a/main.py b/main.py
index 773a67a..dd2af93 100644
--- a/main.py
+++ b/main.py
@@ -4,6 +4,7 @@ import time
 import subprocess
 
 DEBUG = os.environ.get("DEBUG", "")
+DEBUG_NO_SHOW = os.environ.get("DEBUG_NO_SHOW", "")
 INPUT = os.environ.get("INPUT", "./testdata/input.pdf")
 
 def main():
@@ -14,24 +15,13 @@ def main():
             print(splitpage.extract_text())
    print("/main")
 
-def crop(page, x0, y0, x1, y1):
-   if DEBUG:
-      im = debug_im(page)
-      im.draw_lines([
-         ((x0, y0), (x0, y1)),
-         ((x0, y1), (x1, y1)),
-         ((x1, y1), (x1, y0)),
-         ((x1, y0), (x0, y0)),
-      ], stroke_width=5)
-      debug_show(im)
-   return page.crop((x0, y0, x1, y1))
-
 def debug_im(page):
    return page.to_image(height=800)
 
-def debug_show(im):
-   im.save("/tmp/out.jpg")
-   go("qlmanage -p /tmp/out.jpg &> /dev/null")
+def debug_show(im, name=None):
+   im.save(f"/tmp/dnd-pdf-to-txt{'' if not name else '-'+name}.jpg")
+   if not DEBUG_NO_SHOW:
+      go(f"qlmanage -p /tmp/dnd-pdf-to-txt{'' if not name else '-'+name}.jpg &> /dev/null")
 
 def v_split(page):
    clusters = cluster(page)
@@ -51,7 +41,7 @@ def v_split(page):
       im = debug_im(page)
       for x_cluster in x_clusters:
          im.draw_line(((x_cluster, 0), (x_cluster, page.height)))
-      debug_show(im)
+      debug_show(im, name=f'v-split-xclusters-{page.page_number}')
    if len(x_clusters) != 2:
       return [page]
    x = sum(x_clusters) / len(x_clusters)
@@ -115,7 +105,7 @@ def cluster(page):
             ((i.x1, page.height-i.y1), (i.x1, page.height-i.y0)),
             ((i.x1, page.height-i.y0), (i.x0, page.height-i.y0)),
          ], stroke_width=5)
-      debug_show(im)
+      debug_show(im, name=f'cluster-{page.page_number}')
    return clusters
 
 __subprocesses__ = []