[OT] scanned files are large in size
A scanned document from Canon pixma mx870 printer is significantly
larger compared to the same document scanned on a different scanner.
When I look at both the images side by side on a PC, there is no
visual difference between the two. I am trying to understand the
underlying cause and fix it if possible.
As shown below, scanned_in_office.pdf is 332Kb, scanned_on_mx870.pdf is 1.7 Mb.
% ls -al scanned_in_office.pdf scanned_on_mx870.pdf
-rw-r--r-- 1 rajulocal rajulocal 331796 Jan 1 11:54 scanned_in_office.pdf
-rw-r--r-- 1 rajulocal rajulocal 1775460 Jan 1 11:48 scanned_on_mx870.pdf
Both are are scanned at 600 dpi. The only difference I see is in bpc,
enc fields.
% pdfimages -list scanned_in_office.pdf
page num type width height color comp bpc enc interp object ID
x-ppi y-ppi size ratio
--------------------------------------------------------------------------------------------
1 0 image 5104 6600 gray 1 1 ccitt no 7 0
601 600 183K 4.5%
2 1 image 5104 6600 gray 1 1 ccitt no 14 0
601 600 138K 3.4%
% pdfimages -list scanned_on_mx870.pdf
page num type width height color comp bpc enc interp object ID
x-ppi y-ppi size ratio
--------------------------------------------------------------------------------------------
1 0 image 5100 6600 gray 1 8 jpeg no 8 0
600 600 1066K 3.2%
2 1 image 5100 6600 gray 1 8 jpeg no 14 0
600 600 665K 2.0%
Questions:
1) Does the large file size have anything to do with the printer
itself? Is there anything I can do (ex:- update the driver/firmware or
something)?
2) Is the difference in image sizes due to the bpc (1 vs. 8) or
encoding (ccitt vs jped) fields?
3) If yes, how to change them?
thanks
raju
--
Kamaraju S Kusumanchi | http://raju.shoutwiki.com/wiki/Blog
Reply to: