Re: How do I batch change photo DPI settings

"jimkramer" <Newsreader1@xxxxxxxxxxxxxxxxxxx> wrote in message
"Mark W." <mark@xxxxxxxxxxxxxxxx> wrote in message

"jimkramer" <Newsreader1@xxxxxxxxxxxxxxxxxxx> wrote in message

"Mark W." <mark@xxxxxxxxxxxxxxxx> wrote in message

"jimkramer" <Newsreader1@xxxxxxxxxxxxxxxxxxx> wrote in message

"Mark W." <mark@xxxxxxxxxxxxxxxx> wrote in message
"Paul Furman" <paul-@xxxxxxxxxxxxx> wrote in message
Mark W. wrote:
My dumb OCR software will refuse to OCR an image if it's lower than
a 96 dpi setting in it's properties.
It doesn't care that the pixel dimentions are much higher than some
other much smaller pixel dimention
file if it's properties say it's dpi is under 96 dpi.

So, how can I batch change many image files (usually JPEG's) to a
particular dpi property setting?

I'm using Omipage Pro 14 to do the OCR.


Irfanview sounded familiar. Turns out I already had it installed. It
took a few minutes to figure out how to batch reset the DPI's in my
Funny that it always compresses the files to about only 27% of the

I would prefer that it left the file quality alone.

I'm only resetting the DPI numbers. I experimented with resetting to
different DPI's: from the original 72 DPI, to 96, 300, and 600. The
resulting new files are all exactly the same NEW size regardless of
which of
those 3 DPI's I reset the files to.

Am I just unaware that I chose some compression unintentionally?

Couldn't find anything about compression or image quality/resolution
in the
help file.

Under the "options" button (right of the format pull down menu, but
before "set advanced options") Unfortunately it is a slider bar 0-100
so you have to know what your compression is beforehand...


Couldn't find any slider bar.
Is it somewhere in the batch conversion dialog box?
Yes, near the bottom; next question is what version are you using? I'm
looking at 3.91.

4.10 Don't see slider bar or a way to control compression any way at all.
I'm not resizing of course.

I updated my Irfanview to 4.10 and he has moved some things around.
It is in the Batch Conversion/Rename menu.
The Options button, still next to the Output Format pull down menu.
That should pull up a menu with the slider bar to set the JPEG


Thanks so much!
I did a test on a couple of JPEGS with the slider set at 100%. The files
were at 72 DPI and I set the DPI at 300 for the output. The resulting files
were at the same quality and actually a tiny bit larger (by 2.7%) which is
just fine. Funny, but if I reset the DPI of a TIFF file (the same as the
JPEGS aforementioned), it would double the size of the file.
I'm beginning to see that Irfanview has a lot more control options that I'm
totally unaware of.
I guess they offer this quite useful free program as a teaser to get a more
powerful paid version.