sips not setting dpi to 72 of jpg images

This works fine on my 10.8 system. sure you don't have a typo somewhere?

I'm seeing the same thing as the OP. Sips version is 10.4.4 on 10.8.2

When I run the -g to set the dpi sips pauses for a moment as if it is doing sowmthing and the modified date on the jpg is changed to reflect the current time so it seems sips did something to the file

the command I used is

sips -s dpiHeight 72.0 -s dpiWidth 72.0 Scan.jpeg

and

sips -g dpiHeight -g dpiWidth Scan.jpeg

Ah, interesting. The difference is that I used a png file rather than a jpeg. Apparently sips doesn't want to change the dpi on jpeg files (though why that would be, other than a bug, I can't imagine).

Bingo, just tried it on a tiff and it worked. Weird about the jpg and that it's not mentioned (at least I didn't see it) in the man page.

jpeg-2000 (*.jp2) also works.

sips -s format jp2 -s formatOptions normal foo.tiff -s dpiHeight 72.0 -s dpiWidth 72.0 --out foo.jp2

I had the same problem. Running through automator to batch pic resize:

for f in "$@"

do

/usr/bin/sips -s dpiHeight 72.0 -s dpiWidth 72.0 $f

done

not working. Definitely a bug.

Macbook pro / 10.8.2 / sips 10.4.4

Weird... I went through jpeg-2000, using the standard Automator command to change image type and that converted the resolution to 72, even though I did not ask.

So looks like Automator enforces res change to 72dpi for jpeg-2000. Is this normal?

Anyway it comes handy...

onavlis99 wrote:

not working. Definitely a bug.

Works fine in Mavericks.

It does not seem to work in my case: I am trying to set the dpi while converting a PDG file to PNG and it does not make any difference when I experiment with different values with dpiHeight and dpiWidth. Maybe I am doing something wrong, but I not get any error message.

I go to the folder where I have the pdf file and execute:

sips --setProperty dpiHeight 128.0 --setProperty dpiWidth 128.0 --setProperty format png --out myfile.png ./myfile.pdf

or

sips --setProperty dpiHeight 12.0 --setProperty dpiWidth 12.0 --setProperty format png --out myfile.png ./myfile.pdf

In both case I get the same size for the PNG file. It is also the case for other values than 128. or 12. The property is set to the value I give, but the size of the converted image does nos take it into account. My file is always of size 2498x1871 in my case.

--setProperty formatOptions high/low etc. seems to work for the JPEGs, but I need a PNG unfortunately and the compression ratio is not relevant for the PNGs of course...

Any idea on how I can change the effective dpi of the converted image using spis?