Reducing image file sizes

[J. Landman Gay]

Brian Yennie wrote:
> This is just off-the-cusp, so it may be off, but what about:
> 
> 1) Set the fileName of image 1 to the JPG
> 2) Copy the imageData of image 1 into image 2
> 3) Export from image 2 as JPEG
> 4) Scale the final image to the desired size (if necessary)

That's real close to what I was thinking, only I was going to do it in a 
different order. But same general idea.

> The reason why I'm hoping this would work -- imageData is at screen 
> resolution (72 DPI) so this could be a shortcut to getting 72 DPI images 
> if you export from images with only imageData (and no backing file).
> 
> Of course if 72 DPI is too low quality... maybe it would work to scale 
> to double size first, and end up with 144 DPI?

Yeah. I can tinker with it. The main thing is to know what the size it 
is supposed to be when printed. That's where I'm stuck.

> You said that you need to find the original size -- does Rev not open 
> high resolution images at the correct size?

Not really. If the image isn't scaled or put into a locked image object, 
the image opens at its native pixel-count size, disregarding resolution. 
So if the image is thousands of pixels wide, Rev uses thousands of 
pixels to display it. A 2-inch image saved at 72 dpi will open at half 
the display size of a 2-inch image saved at 144 dpi. All Rev gives you 
is the pixel count.

-- 
Jacqueline Landman Gay         |     jacque at hyperactivesw.com
HyperActive Software           |     http://www.hyperactivesw.com