advice resizing images

[Savanna]

Hi All, 
I'm looking for advice on resizing  images. I have used the scale tool to resize them individually, but find it quite time consuming and at times a bit trial and error.

I post pictures on a modeling site, and they need to be below 3mb, but not too small or they are not quality enough to be viewed properly, and the site system bitches at you continually that you have  images that are too small.. 

Firstly, on an individual basis using the scale tool, is there a way to determine the finished size of the image in MB? As all images vary in their starting size, i never know how much to reduce them by so find myself reducing a bit, saving, checking, then repeating as much as possible trying to get them to as close under 3mb as i can - that's time consuming lol

Secondly, is there a way to batch resize images in GIMP?

[rich2005]

Just a couple of questions that might help with answers.

What image format do you normally sent to the site - png - jpeg -tif ...or..something else?

What computer operating system do you use - Windows 7 / 10 - Linux - OSX ? That might determine any plugins etc that can be used.

For Windows there is a batch plugin BIMP that resizes https://alessandrofrancesconi.it/projects/bimp (I can maybe help with linux if you use that)

[Blighty]

(05-12-2019, 06:58 PM)Savanna Wrote: and the site system bitches at you continually that you have  images that are too small.. 

Does the site have a spec for image sizes? In particular, the image size in pixels.

[Savanna]

(05-12-2019, 07:21 PM)rich2005 Wrote: Just a couple of questions that might help with answers.

What image format do you normally sent to the site - png - jpeg -tif ...or..something else?

What computer operating system do you use - Windows 7 / 10 - Linux - OSX ? That might determine any plugins etc that can be used.

For Windows there is a batch plugin BIMP that resizes https://alessandrofrancesconi.it/projects/bimp (I can maybe help with linux if you use that)

usually jpeg, as that's normally the image format i receive, but it also takes PNG  - not tried anything else

OS is Windows 7

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(05-12-2019, 07:30 PM)Blighty Wrote:

(05-12-2019, 06:58 PM)Savanna Wrote: and the site system bitches at you continually that you have  images that are too small.. 

Does the site have a spec for image sizes? In particular, the image size in pixels.

Am looking now - will let you know if/when i find out.. but i don't  *think*  so.. think it just has a 3mb limit..  would be simpler if they gave a pixel guide

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(05-12-2019, 07:30 PM)Blighty Wrote:

(05-12-2019, 06:58 PM)Savanna Wrote: and the site system bitches at you continually that you have  images that are too small.. 

Does the site have a spec for image sizes? In particular, the image size in pixels.

Asking on the forums there, this is the reply:

There's a file size limit. But if you upload anything more than 900px wide it will be resized down to 900px wide, so you might as well take charge of your own image resizing and sharpen as you see fit.

[rich2005]

Quote:..There's a file size limit. But if you upload anything more than 900px wide it will be resized down to 900px wide, so you might as well take charge of your own image resizing and sharpen as you see fit...

That sounds like sensible advice. 900 pix wide is not large so unlikely to be 3 mb file size.

There is an old plugin 'save-for-web' that can both resize and gives a file size estimate in a GUI.

I hope your Win7 is 64 bit, the attached zip includes both 32 and 64 bit versions but the 32 bit webexport32.exe does not work on large images. It does work on smaller images. This an example: https://i.imgur.com/YFNsFHc.jpg

Taking your forum advice about scaling to 900 pix wide yourself. If you do that, do a little pre-blur first. For about 50% scale down, use a gaussian blur with a value of 2. For 25% - use a value 4. Less than 25 % is usually a disaster in my opinion.

You can get an estimate of file size using the regular Gimp export jpeg function. Tick the  'show preview'  option. Example https://i.imgur.com/JkWGOYu.jpg

For the save-for-web plugin. Unzip, use either the 32 or 64 bit version depending on your Win7. 
Put the file webexport64(32).exe in C:\Users\"yourname"\.gimp-2.8\plug-ins The plugin shows up in the File menu.

The BIMP plugin will resize a collection of images down to 900 wide and apply some sharpening etc. No way to determine the file sizes however.

[ahmad]

(05-12-2019, 06:58 PM)Savanna Wrote: Hi All, 
I'm looking for advice on resizing  images. I have used the scale tool to resize them individually, but find it quite time consuming and at times a bit trial and error.

I post pictures on a modeling site, and they need to be below 3mb, but not too small or they are not quality enough to be viewed properly, and the site system bitches at you continually that you have  images that are too small.. 

Firstly, on an individual basis using the scale tool, is there a way to determine the finished size of the image in MB? As all images vary in their starting size, i never know how much to reduce them by so find myself reducing a bit, saving, checking, then repeating as much as possible trying to get them to as close under 3mb as i can - that's time consuming lol

Secondly, is there a way to batch resize images in GIMP?

I recommend you using online image resizers like pixellair.com . You can simply drag all your images in the site and then choose how you want to resize them. then just download all your files in a .rar file