File size after 'save'

[ratsea]

We have been using Irfanview for years now and have been really satisfied.

We have recently noticed that the Save and Save As functionality seems to have changed. This maybe a Windows 10 effect, but we are finding that if you open a 5Mb photo and say auto adjust colours then save it to the original folder with the default save settings, the resulting file is only about 1Mb.

If the save quality setting is increased from 80 to 100, the file is then 10% bigger.

Please advise if something has changed as we are sure that this did not happen last year.


Dell Inspiron 64bit, Windows 10 v1607 with Irfanview 4.42 x64

[Bhikkhu Pesala]

Nothing has changed as far as I know. Several different settings can affect the file size of JPG images and how much difference there is between 80 and 100 compression settings will depend on the image itself.

1. Do the original images contain Exif data? If so, stripping it on save will reduce the file size.
2. Try to save with original JPG quality (estimate) will ignore the compression slider and may increase or decrease file sizes.
3. Disabling Chroma subsampling will increase file size.
4. Using the RIOT plugin will ignore the compression setting and try to fit to the specific value set.