PDA

View Full Version : Need help here. Image compression.



Maxico
11-17-2003, 10:36 AM
I recently decided to put my own avatar down for this forum. I used photoshop and get the avatar I want. and see that it needs to be 5125 bytes in size. I use a fairly low quality jpeg and photoshop says its 5 bytes. then the forums say its too big. I realised that when I select the photo out of PS it says its 11k. I have stored It at even lower qualitys and shrunk it down to 30/27 pixils but its still around 7k. How the hell can I get an image as high quality as I sometimes see here without it looking like don king on a bad hair day (a large blob)

crono_logical
11-17-2003, 02:24 PM
I think we can say Photoshop officially sucks at file size estimates then :D I remember someone else here had a similar problem with their sig not too long ago. The size it says out of photoshop and in Explorer is the correct size.

Avatar limit here is 5120 bytes, and 60x60 pixel image, not 5125 bytes :p You probably need to reduce the quality of the jpeg (but you can keep the image at 60x60), you've set it too high, and it really is pointless being set that high when the image is so small. I find a jpeg of pixel noise and random garbage at 60x60 pixels when saved at 90% of the maximum gives under 5k, so you've clearly set something wrong if you can't get it that small for something that isn't randomised. Alternately, try saving in gif format, the board accepts that as well.

If all fails, attach it and someone here can fix it for you :p

Maxico
11-17-2003, 02:59 PM
Thanks. I havn't tryed the GIF format yet.

EDIT: ok no need to post it in because the GIF format worked perfectly. I need to remember that.

crono_logical
11-17-2003, 03:09 PM
As a test, I saved your avatar as a jpeg at Maximum Quality and 24-bit colour, and the result was under 4k for me, so I dunno what you were trying to do :p

Maxico
11-18-2003, 04:09 PM
Thats strange. Even on minimum quality it wasn't small enough for me. I guess photoshop has crappy conversion.

Miko
11-02-2010, 05:47 PM
Thats strange. Even on minimum quality it wasn't small enough for me. I guess photoshop has crappy conversion.

Reducing an image for an avatar, into the single digit k's

Yes, if you can believe that, Photoshop IS crappy at making things really small. Here's what nobody else is telling you: you need to use a lower grade photo software after your main prep work in Photoshop.

So you go into Adobe PS and you crop, and set you pixel dimensions usually 80X80 or 64X64), and your dpi (72), and then you save as a PS .jpg with good quality. Actually next time I'm gonna try max quality.

The avatar I'm using here on Eyes On was a 72k .jpg sized 80X80 pixel, saved out of PS at good quality, I think #8 jpg compression. (I am using Photoshop CS3 v10 on Mac OS X)

NOTHING I did in Photoshop could get that image anywhere near single digit k's, including lowest quality compression settings, stripping out all color profile info, preview and thumbnail data, changing to indexed color - doesn't even come close. As a matter of fact, going to 256 local web palette colors with no dithering made it even bigger. Ha!
I have 11 yrs career experience in digital imaging and this was making me a little crazy too. Definitely scratching my head wondering WHAT was going on.

Here's the zaniness of it - I bring it into Preview (default Max OS X image viewer) and save it at MAX quality (yes, that's right, I slid the quality slider UPWARD from the default "good") and it saves out as 8k.

So you are right! Photoshop is crappy at reducing.

Mirage
11-04-2010, 05:16 PM
PNG-8, 16 colours, 1.7 kB, Photoshop CS5

I have no idea what you guys are talking about.

Even as PNG-24, which is lossless, it's below avatar size limits (2967 bytes).


What's strange though, is that photoshop thought this image would be 925 bytes before it saved it, but it turned out 1.7 kB.

-edit-
Miko's avatar, 6.1 kB, max quality jpeg.

I had similar results when I was working in Photoshop 8 too, back in the day, so i doubt this is something that's been improved on a lot in the latest version. I've never had any problems with getting file sizes down to below avatar limits.

rubah
11-05-2010, 05:31 AM
Why the fuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuudge are you replying to a 7 year old necropost, ståle?

Mirage
11-05-2010, 05:55 AM
rofl, i never check dates :(