Image size for posting

[RonH]

The maximum size of images posted to Eileen's Lounge is 250KB.
Image editing softwares often have settings to resize on the basis of pixels and/or image dimensions. What simple image file resizing software do members recommend for posting on the forum.

[HansV]

Stuck has mentioned IrfanView

[RonH]

Thanks Hans.
There are a lot of online resizers but I like to keep in-house as best possible. IrfanView I will check.
The other way is to use the Windows in-house resizer eg trial and error small, medium, large or custom. It's quick and easy but lacks resizing by file M/kbits.

[RonH]

Regards IrfanView,the faq's state:

Note: since version 4.20, a new JPG save option has been allowed: Set file size.

Can't find that under Image or Edit in Version 4.60 ... anyone know where this is located

[stuck]

...IrfanView I will check...

It's not actually IrfanView that works the magic of reducing many megabyte image files to only a few KB yet some how retaining high quality. It's a plugin, called RIOT, that does it. It is very easy to use and invoked via the option 'Save for web' that's on Irfanview's 'File' menu.

That's the good news.

The bad news is that as of IrfanView v4.58 (latest is v4.60) the 'Save for web' feature no longer works. The explanation for this is on this page:
    https://riot-optimizer.com/riot-reaches ... g-changes/
underneath the heading "Future of the RIOT plugin". In summary, it's mixture of tech. constraints and developer disagreements with the end result being the latest version of the RIOT plugin is not compatible with IrfanView v4.58 and higher and unlikely ever to be compatible with IrfanView again in the future.

There are workarounds:
1) Do not upgrade IrfanView beyond v4.57.
This is my chosen option, you can get this old version, and the associated plugins (you must install these as well) from here: https://www.fosshub.com/IrfanView-old.html. Yes, that link is to the 32 bit version of IrfanView, I did try the 64 bit version once but I quickly reverted to the 32 bit version. I can't remember why, presumably it didn't behave as I expected in some way.

2) Download the full version of RIOT and use it as a stand alone app.
RIOT is free, get it here: https://riot-optimizer.com/download/ but being able to use it as a plugin is much more convenient for my image handling workflow.

3) Wait until XNView has support for the latest RIOT plugin.
This is apparently already in the pipeline, again see underneath the heading "Future of the RIOT plugin" on the page I link to above. I am likely to explore this option when it becomes available. If it suits my workflow then after many, many, happy years of being an ardent IrfanView user I will leave it behind.

Ken

[Graeme]

Windows Paint does a jpg resize. It's a bit unhelpful in that you don't know the final file size until after you have saved it but the file size value is displayed at the bottom of the screen. I do a file resize and check it a couple or three times until it's under 250kb. It sounds a bit long winded but it only takes a minute.

Regards

Graeme

[RonH]

Thanks for all comment and specifically Ken for your very detailed explanation and links.
Graeme ... seems that Windows Paint uses the same Windows Resize that I referred to above.

[GeoffW]

There are options on mobile devices as well. I use "Photo & Image Resizer" for Android as a quick option - I'm sure there are others.

[ChrisGreaves]

The maximum size of images posted to Eileen's Lounge is 250KB.

i use vso image resizer 4.0.3.2 both for resizing iamges for Eileen's Lounge down to 250KB and for resizing images for my various blogs/diaries/web pages. VSO offers a range of templates, and the ability to save to the original or to make a copy, and much more.

Untitled.png

Cheers, Chris

[RonH]

Thanks Chris,
As far as I know, there's no direct way to correlate pixel size and file size. A case of trial and error to arrive at or less than 250KB which is what I currently do for posting on forums etc.
Using multiple devices (camera's, smartphones etc) complicates this trial sizing.

[RonH]

Ken,

I have installed RIOT as a standalone and it does the job
Thanks for the tip.

[stuck]

I have installed RIOT as a standalone and it does the job

I thought it might. The RAW files from my Canon 90D are about 30 MB, once processed generally they end up as 130 MB TIFFs. RIOT then allows me to resize them down to under the 256 KB limit here in The Lounge. Despite this massive reduction the pictures still manage to look good (at least to me).

Ken

[ChrisGreaves]

I have installed RIOT as a standalone and it does the job

Greetings. Ron, Great Guru of Graphics.

Untitled.png

I decided to "2) Download the full version of RIOT and use it as a stand alone app.", then dragged 435 images to my ramdisk (no point in corrupting original files on a first essay), found Batch mode, and thought to resize all images to 250KB.
I expected RIOT to determine the percentage reduction for each image, so that I ended up with a gallery of 435 images, any one of which could be uploaded to Eileen's Lounge.

I wanted only that every image be reduced to 250K.

Before I start annoying people on the RIOT forum, have I missed something from your post where you said "I have installed RIOT as a standalone and it does the job"?

Have I misunderstood? I gained the impression that you had managed to make RIOT reduce every file in a batch to exactly 256KB, without trial-and-error processing.

Thanks, Chris

[Ted Myers]

On my Win 10 PC, I put the image on the desktop and hover the cursor on it. Can't try Win 11 as I don't like it.
-

TM.png

[stuck]

...I wanted only that every image be reduced to 250K...

I've never tried to process a bunch of images in one batch BUT whenever I resize one of my photos for The Lounge the first thing the RIOT plugin does is ask me to set the dimensions of the output image. Typically I set the long edge to be 800 pixels (which, preserving aspect ratio, automatically makes the short edge 533 pixels). I then set the output size to be 256 KB, and let it do its stuff.

Given that, I expect the safest way to batch process images is to ensure each batch contains ONLY landscape or ONLY portrait orientation files. Then decide what length you want for the long edge and enter that. Then set the output size to 256 KB.

Ken
PS there's one more JPEG output setting you might want to tweak and that's the 'chroma sub-sampling'. I've got mine set to 'None (4:4:4)', to preserve as much colour data as possible.

PPS the native long edge length of the images from my DSLR is 6940 pixels. I use a length of 800 pixels for the long edge because that still gives a reasonable size image when viewed in The Lounge. I do sometimes I use a longer length but then the amount of compression required to get the size down to <256 KB is greater and the quality can then suffer, i.e. image dimensions and final file size are a trade off / compromise.

[stuck]

My latest use of IrfanView's 'save for web' is here:
https://eileenslounge.com/viewtopic.php ... 46#p295846
Ken

[RonH]

I have installed RIOT as a standalone and it does the job

Greetings. Ron, Great Guru of Graphics.
Have I misunderstood? I gained the impression that you had managed to make RIOT reduce every file in a batch to exactly 256KB, without trial-and-error processing.

Thanks, Chris

Ken is the guru on RIOT as per his very informative post. I am just introduced so need some mileage.
Chris, for any batch processing for uploading to a print house, I use Photoshop Elements... this does not adjust to a specific file size on all images but is helpful to reduce the overall MB upload of typically 200+ images.

[ChrisGreaves]

...the first thing the RIOT plugin does is ask me to set the dimensions of the output image.

This almost makes sense. I wrote an Excel VBA that worked out the optimal zoom factor to fit a worksheet on to an integral number of sheets of paper - avoiding that embarrassing problem at the corporate laser printer where the last twenty sheets came out 99% blank with a trickle of digits down the left hand side.

In terms of an image, there are three factors - height and width in pixels, and size in bytes.
Size must be a function of height and width.
But then given a Target Size and the original height and width, we should be able to apply a simple formula to determine what scaling (that is, new height and new width) is required to fit to a new size limit.

i guess that our RIOT programmer didn't go that route.

There again, what do I know about image enhancing and resizing, right?

i did the Excel job by brute force, trying a series of zoom factors, within a range of factors, in portrait or landscape or both, until I found one that delivered the minimum number of sheets of paper to be output.
Programmed brute force ought to be possible with RIOT - we can do it manually after all - with a caution about processing time.
Cheers, Chris

[stuck]

...There again, what do I know about image enhancing and resizing, right?...

Probably not much more than I do!

Meanwhile, my best guess at why RIOT doesn't work the way you suggest is simply that nearly all users want to be able to specify the dimensions of their output, i.e. they don't want the application to decide that. For example, if I were to use RIOT to resize stuff so I could print the output at a certain size then I'd want to specify the dimensions in multiples of 360 pixels per inch because my printer is an Epson and the native print resolution of it is 360 dots per inch. However,if I had an HP or a Canon printer I'd want to specify in multiples of 300 ppi, because those printers operate at 300 dpi (NB I KNOW ppi and dpi are NOT the same and equating them like this is a MASSIVE can on worms.)

Ken

[ChrisGreaves]

...why RIOT doesn't work the way you suggest...

Hi Ken.
I have been thinking that ... the type of image also imposes a constraint.
Consider two images from Google Maps, one in map view, one in satellite view.

Untitled.png

Both screen images cover the same area (roughly one square kilometre) but the sizes are roughly five-to-one.
Were I to compress both images to 250KB, the satellite view would shrink to a postage stamp, whereas the map view would be the size of a postcard.

Untitled2.png

When I am producing screen shots of my VBA code and MSWord document text the difference is not so apparent, because in both cases the screen is largely white-space. [which one is the document, which two are the associated VBA code?]

And of course my choice of PrtScr format (PNG) will have an effect.

So what? I suspect that the usefulness of compressing to a threshold while retaining the aspect ratio will be limited to images of a similar appearance.
The technique will work well for mixed images of VBA code and DOCument text
The technique will NOT work well for mixed images of map and satellite view.

Cheers, Chris