compress: not if, but how much?

[pixelmonkey]

yes, this is concerning how much to compress images before posting them online. thinking main disaply images located in the header, and navigation sections of a portal-type site.

a small arguement going at the moment on the revision of a few images on the pages mentioned, and the only thing holding me back is load time.

NOTE: the image quality is better, and sizes are around 4128. this is up from 3329

i'm not looking for someone to compress these images, just your thoughts and struggles on keeping others happy when it comes to online images.

any guidelines on how far to go? which format for which images?
thanks
chris<pixelmonkey> /emoticons/icon_biggrin.gif

the monkey makes all the girls bounce!
*i'm an aerobics instructor too*

Jpgs for pictures or complex gradients @ 60-80%

Gifs for vector artwork, text or simple graphics. Color selection depends on what your compresing.

[Big Perm-dizzle]

i compress until I see artifacts then I back it down a hair....

smaller file size = faster loading

JUST LAUNCHED - www.hirethisdesigner.com (http://www.hirethisdesigner.com) - check it out

[Ryan8720]

I compress until it starts to look noticably worse than the original.

Are those numbers you posted bytes or kilobytes?

For a portal, smaller is especially better, since so many pages have it.

http://edgewebdesign.org/ryan2.gif (http://www.edgewebdesign.org)

C:\DOS
C:\DOS\RUN
RUN DOS RUN

[Benjamin]

Each image will be different so, as Perm says, try it and see what is acceptable in each case. Also, it is possible to compress different areas of the same image differently I think. You can also use blurring to optimise. I don't actually bother with these last 2 things but they could be handy for v. large images perhaps.

http://www.jackfruitdesign.com/
Om Namah Shivaya

[pixelmonkey]

our public relations group has asked for something of a standard by number, and not a varriable image-by-image basis on compression. i've tried to describe it other ways, but it cant be done. i think i'm going to leave the question forgoten and keep doing things the way they have been.

chirs<pixelmonkey>:D

the monkey makes all the girls bounce!
*i'm an aerobics instructor too*

Benjamin said...
...Also, it is possible to compress different areas of the same image differently I think. You can also use blurring to optimise. I don't actually bother with these last 2 things but they could be handy for v. large images perhaps.

I tried that but don't do it. Each compression assigns different color values and your slices will look noticeably different.

I hardly experiment with JPG compression and if it was up to me I wouldn’t even compress. I like the effects and the clean look to be as noticeable as possible. I also hate compressing anything with to much black.

I honestly don’t care if I’m using a picture and it has black I make it a Gif. I hate and I feel very strongly about this the JPG compression on black. You see all type of swirls of purple, blue, red in your image if you use jpeg compression on a image with a lot of black.

I’m a designer and I know a lot of people concentrate on file size but I concentrate on what you see. First is the look to me then the file size.

[YellowDart]

lol... so they want you to tell them how big all file sizes will be??? Even if they're different images??? While your at it, why don't you tell them the meaning of life. =P

I typically do most photos as jpgs w/ medium or higher compression.

Vector, line art, text, and gradients I usually do as gifs. *ducks flying objects* I know, I know, but gradients can still see a pretty nice transistion under the Adaptive color palatte and a patterned dither. They tend to look a little crisper that way than a heavily compressed jpg... and can often times retain a smaller file size.

With text, you can usually get away with limiting your color palette to 4-8 colors... so most text images can be smaller than 1k in file size. Also, try slicing your images as well... if you slice them into smaller portions, the sum of their parts is smaller than the original file size. ;)

God Bless the Adaptive color palatte. That thing is great.

I also agree with using it for some gradients not all just some.

[Benjamin]

I have a feeling that different programs compress differently, so in photoshop a jpg set at 60 might not actually be compressed in the same way as one set at 60 in fireworks, for example.

http://www.jackfruitdesign.com/
Om Namah Shivaya

[Ryan8720]

Yep, they compress differently. Photoshop does a much better job than Paint Shop Pro. I use GIFs for most of my images. I don't like JPG and only use it for photographs and very large images. I also use PNG, but I won't be able to use if fully until Microsoft gets off their ass and supports it.

http://edgewebdesign.org/ryan2.gif (http://www.edgewebdesign.org)

C:\DOS
C:\DOS\RUN
RUN DOS RUN

[YellowDart]

Ryan8720 said...
Yep, they compress differently. Photoshop does a much better job than Paint Shop Pro. I use GIFs for most of my images. I don't like JPG and only use it for photographs and very large images. I also use PNG, but I won't be able to use if fully until Microsoft gets off their ass and supports it.

Microsoft??? get off their ass??? hehehe... good one Ryan. ;)