Re: [Gimp-user] resizing

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


Liam Quin,
Available for XML/Document/Information Architecture/XSLT/
XSL/XQuery/Web/Text Processing/A11Y training, work & consulting.
Web slave for vintage clipart

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