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View Full Version : jpg to gif?



sunny
03-29-2006, 12:07 PM
hi,
Normally, gif's take up less space than jpg's.But when i tried to make gif out of jpg's.they took more space? I have kept my images on angelfire for my friends to see.but they find it difficult to open a image as even a single file is of almost 325kb.what should i do now?

neilkw
03-29-2006, 12:11 PM
Hi sunny

Are your original jpegs at 72 dpi/PPI ?

simonf
03-29-2006, 01:35 PM
A 640*478 JPG at 72DPI should be around 50K... this would provide a suitable sized photo and still allow for Ok speed.

If you pics are around the 350K mark they are large photo's (aprox 1200x900). You could have these in a seperate directory and link the smaller photo to the larger one if the person viewing the site wants to see a bigger, higher quality image.

mwinter
03-29-2006, 01:41 PM
Normally, gif's take up less space than jpg's.But when i tried to make gif out of jpg's.they took more space?GIF and PNG images are generally more space-efficient only if the image is relatively simple, with lots of blocks of uniform colour, or repeated sequences. Images that are more photographic in nature - that have many colours and a lot of fine detail - will compress better as a JPEG.

The JPEG format uses a lossy compression algorithm, where some data is lost to achieve better compression. The compression level can usually be adjusted when saving the image, and can often be set to around a third of the maximum before artifacts start becoming noticable. How you set the compression level will differ between programs, but can probably be found in the Save As dialogue, or image properties.

Mike

.alias.
03-29-2006, 02:30 PM
yea mwinter is right GIF and PNG are better for small images, so for big images use JPEG

Twey
03-29-2006, 02:53 PM
GIF and PNG also offer variable compression levels.
.alias.: Mike is almost always right. There's no point agreeing with him. :p

.alias.
03-29-2006, 02:55 PM
lol ok i wont in future, i also noticed that GIF files can cope with clear backgrounds whereas JPEG can't.

Twey
03-29-2006, 02:59 PM
Yes. It's not very relevant to the thread, but GIF can handle transparency. However, the way it does it is to define one colour out of the palette as "transparent." This means that you can have only pure transparency, and can't do things like translucent colours that you can with PNGs, which utilize an optional alpha channel (each pixel has an alpha value as well as red, green and blue). Unfortunately, IE has problems with alpha transparency.

.alias.
03-29-2006, 03:01 PM
yea tell me about it it realy sux that IE can't handle it, its one of the worst problems with IE i think.

mwinter
03-29-2006, 03:03 PM
GIF and PNG also offer variable compression levels.They certainly should be able to as, if I remember correctly, their compression algorithms feature parameterisation. However, I don't think it's as common to find them. Paint Shop Pro, the editor I use on the rare occasions that I do anything with graphics (I'm no artist so it really isn't my thing :(), doesn't feature compression controls for either format.


.alias.: Mike is almost always right. There's no point agreeing with him. :pLMAO :D

Mike

Twey
03-29-2006, 03:07 PM
Paint Shop Pro, the editor I use on the rare occasions that I do anything with graphics [...], doesn't feature compression controls for either format.The GIMP has compression controls for PNG, but not for GIF. To be honest, I don't really see the point in offering this functionality for lossless algorithms.

KevinKraft
09-01-2006, 03:29 PM
Hello...which format is better to embed in an email, jpg or gif?
I created a signature at the bottom of my email to display some reviews of my works. The signature contains 14 small GIF logo images of newspaper logos (New York Post, etc) that total 256KB. When I email it to myself as a test, I can see everything very well. However, some of my recipients either don't see the images or their email program crashes when they open the email.

So I went back and converted all the GIF images to JPGs, and took 4 images out. So there are now only 10 images totaling only 40KB. However, this new signature takes MUCH longer to load and send (30 seconds sometimes) than the signature with the GIF images.

Can anyone please advise me the best way to create the signature I want? Should I use GIF or JPG? Do GIFs travel through the internet better than JPGs, even if they are larger files? What's the best way for me to accomplish what I'm tring to do?

Thank you!

Kevin Kraft
Kevin@KevinKraft.com

Twey
09-01-2006, 03:37 PM
However, this new signature takes MUCH longer to load and send (30 seconds sometimes) than the signature with the GIF images.What're you on, i386? o.@ There shouldn't be a major difference between the loading times of the two formats; they're both compressed, and due to their using different algorithms, it's theoretically possible that one would take slightly longer than the other to load. However, I wouldn't expect it to take longer than five seconds on even the slowest systems (after it's downloaded, of course).

JPEG is definitely the way to go for embedded images.

jscheuer1
09-04-2006, 09:07 AM
The way to adjust 'compression' (actually, image size relative to quality) with .gif is to reduce or increase the number of colors used and/or to increase or decrease dithering. Png's can be adjusted in this manner as well but, if there are less than the maximum colors (or perhaps less than a certain amount of colors), the alpha channel is no longer available.

The alpha channel (opacity) feature of the .png format is supported in IE - as a filter:

http://msdn.microsoft.com/library/default.asp?url=/workshop/author/filter/reference/filters/AlphaImageLoader.asp

This is not to be confused with the IE filter:alpha() which is for setting the alpha channel opacity of any element.