Resizing pictures

[jyeh74]

I have a 3mb pic and i use Microsoft Picture Manager to resize to 25% of orginal size. The new size is 300 kb (even though 25% of 3mb is technically 750kb) But when I save it, and open it and compare it to the original 3mb, it looks identical. So how can this happen? Picture quality did not suffer but the size of the file is way smaller size than original size.

[olyteddy]

But when I save it, and open it and compare it to the original 3mb, it looks identical.

That's how lossy compression works. The goal is to look identical.

[jyeh74]

the compression doesnt seem like there is any loss in quality at all though. I always thought with smaller size = smaller and lower quality.

[thecoalman]

With the larger image you're not viewing the image at it's full resolution. Computer monitors cannot display all the information available. While this may not make a difference for viewing over a monitor it's going to make a significant difference if you were to print a 8*10 photo. Same thing will apply in the future as monitors get better.


edit:

the compression doesnt seem like there is any loss in quality at all though.

Compression and resizing are two different things. You're most likely doing both.

[El Heggunte]

I have a 3mb pic and i use Microsoft Picture Manager to resize to 25% of orginal size. The new size is 300 kb (even though 25% of 3mb is technically 750kb)

Microsoft Picture Manager is evil.

BTW... "25% of the original size" of the image, OR of the file