Re: [Gimp-user] resizing

[Liam R E Quin <liam holoweb net>]

On Sat, 2019-07-20 at 20:28 -0400, Helen wrote:
> Sorry!  I meant to say, Is there a way, in GIMP, to size a picture to
> precisely 1.5 megabytes?

For an 8-bit precisoin RGB image like JPEG, each pixel uses 3 bytes of
memory. So the image will be three times bigger than we might expect.

So, divige 1.5 megapixels by 3 and aim for that number.

1.5 megabyets is 1024 * 1024 * 1.5 is 1572864, but we have to divide
that by three, which gives us 524288 pixels.

So it's the same except with a new number:
> > 1. divide 1572864 by the current image width in pixels.
1. divide 524288 by the current image width in pixels.
> > 2. multiply that number by the image *height* in pixels
> > 3. take the square root of that result
> > 4. put that number into the Height field in Scale Image
> > 5. the Width field should update auomatically

To get the image size in the title bar (it's already in the status bar)
go to Edit->Preferences; under Image Windows near the bottom is Title &
Status. In there at the end of the Image Title Format, add a space and
then (%m) to get the memory size.

I also find it useful to put %EE at the start (with a space after it),
which gives an E if the image has been exported since it was last
changed.

Liam




-- 
Liam Quin, https://www.delightfulcomputing.com/
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