Requested Multi-target format in batch converter

[Saul Luizaga]

What I need: I need the smallest file size, regardless of format. So you could use concurrency multi-core processing, which BTW you don't use for any conversion: single or batch, I highly recommend it. Sometimes I need to test 3-4 formats at once, and each format sometimes makes bigger files than others, so I need Irfanview to let me select what results to keep: size, smallest.
Thank you

[Bhikkhu Pesala]

A wild goose-chase. For example, a photo saved as WebP at the same compression/quality setting as a JPG will typically be smaller.
Whether you find the quality worse/better is subjective. PNG will generally be better for images with fewer colours, e.g. user interface elements like dialogs or toolbars. If your aim is just the smallest file, you will never get optimal results.

Again, the type of image data being compressed matters a lot. A seascape will be more forgiving at high compression than a landscape, which will be more acceptable that a photo of buildings, text, or machinery.

[Saul Luizaga]

You completely misunderstood: I'll configure the plugins that I want to test and then proceed to produce the 3-4 formats of a single original image, to check for size, and only keep the smallest one. I know what results to expect according to configuration. So I need this function to keep the smallest size files on Batch Conversion. I explained this on my original post and has nothing to do with what you wrote about

[IrfanUserGuyxyx]

Use batch to create the files and a windows script to delete the larger files.

[Saul Luizaga]

Interesting, didn't know that was possible; but no, I want an app that automates it, scripts are poor man's solutions and last resorts

[Bhikkhu Pesala]

Send your request to Irfan Skiljan and tell us what he says. See IrfanView Help, About for his email.

[IrfanUserGuyxyx]

I don't feel poor...

[Saul Luizaga]

Well it is a poor solution

[Bhikkhu Pesala]

Choosing the compression method on file size alone is a poor solution. There is a trade-off between file size and image quality.
For Photos, JPG tends to be bigger than WebP for a similar quality, though some users don’t like the blurry appearance of WebP. JXL may be better than both, but they are not widely used, and may not be uploadable to all sites.

JPG Highest quality = 73.2 Kbytes



WebP Highest Quality = 62.3 Kbytes



JXL Highest Quality = 59.4 Kbytes

Not uploadable.

PNG Lossless = 224 Kbytes