Use Python version of Jpegize as a preparation

mpegize.py

@@ -1,5 +1,5 @@
 #!/usr/bin/python3
-# Copyright 2022 Pavel Machek, GPLv2+
+# Copyright 2022, 2024 Pavel Machek, GPLv2+
 
 import os, sys, time, copy, subprocess
 
@@ -64,7 +64,9 @@ class Mpegize:
                 m.stat_gaps("sa")
                 return
             if mode == "jpegize":
+                m.prepare()
                 m.jpegize()
+                return
         m.help()
 
     def stat_gaps(m, e):
@@ -212,8 +214,8 @@ class Mpegize:
 
     def jpegize(m):
         i = 0
-        os.chdir(m.source)
-        l = os.listdir(m.source)
+        os.chdir(m.base)
+        l = os.listdir(m.base)
         l = filter(lambda n: n[-4:] == ".dng", l)
         l = list(l)
         l.sort()
@@ -235,7 +237,7 @@ class Mpegize:
                             '-T', n])  # -T Output TIFF
             subprocess.run(['convert', base+'.tiff', base+'.jpeg'])
             os.unlink(base+'.tiff')
-            os.rename(base+'.jpeg', base+'.jpeg.sv')
+            os.rename(base+'.jpeg', m.source+"/"+base+'.jpeg.sv')
 
 m = Mpegize()
 m.run(sys.argv)