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Old 07-15-2009, 11:34 AM   #7
frediz
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frediz began at the beginning.
 
Posts: 14
Karma: 10
Join Date: Mar 2009
Device: prs 505
Quote:
Originally Posted by Kostas View Post
Hi frediz, thanks again for the precious info!


No! Maybe the low value is due to the fact I was trying to split plain A4+ pages (750 x 1000 pixels) with 3 or 4 rows of comic strips per page.


Yes, I did play with the s option, but I got better results tweaking on the value of m.
After a few test, I got 46 pages automatically horizontally splitted in 30 secs!!

Cpu's algorithm was "intelligent" enough to autodetect whether there were 3 or 4 rows, with only one failure!!
Much better than anything that I could get with papercrop which, besides, degrades a lot the quality of the image, despite my efforts to tweak it.


Wow! cpu is far beyond my expectations as is now!
I'll add a vertical splitting filter, this will avoid the workaround (and
additionnal time) of rotating back and forth the pictures with mhs.
Quote:
Originally Posted by Kostas View Post
Besides, I'm pretty sure that I don't get the difference between mean and average splitting!
mean ? min ?
Actually splitting is done this way : horizontal lines of pixels are read one by one
from top to down. All the pixel color of the line are converted to a gray level. From black pixels (value 0) to white pixels (255)
When the current line meets a criteria (provided other criteria such as s are also ok) the picture is cut here.
The criteria can be :
- minimum criteria (mhs) : the pixels should all be lighter (whiter ?) than a given value m : this way of doing will rarely cut dark lines in the picture (depends your m).
- average criteria (ahs) : an average of all the pixels value of the line is computed and it shouldnt be too dark to be cut. This means that if the line
is white with few black pixels, it could be cut. This criteria is less strong than the one of mhs and your pictures could be cut in more places, not necessarly the good ones. Depends.

Sorry for my bad english, I hope to be understandable though
Quote:
Originally Posted by Kostas View Post
Frediz, you rock!

PS: With an effort on producing clearer instructions, I think this topic deserves a sticky status.
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