Oh, for those not so informed about image formats I should add: there's not only the format, you still have parameters like * compression/quality in jpeg * number of colours in gif and png The best is to play around, look at the previews (or results if your program doesn't have a preview) and learn yourself. I'd say that I could certainly compress the average web image* to less than 50% of it's current size without a visible quality loss. And very probably even more could be economized. *considering all of the images in the internet
LOL Amen brother, I had a good laugh reading the last paragraph. "they don't know enough about web development to code their way out of a piss soaked paper bag", classic. xD
You should try 8 bit palettized .png - same capabilities including single color transparency, same browser support as .gif (even works in IE), and usually smaller file sizes on anything more than 16 colors. You can even eliminate the color gamma issue using tweakpng.exe http://entropymine.com/jason/tweakpng/ Though photoshop is a bit of a retard about handling them - which is why I do all my final saves from Paint Shop Pro.
as well as how much dithering if the program you are saving with supports it. Again, cannot recommend Paint Shop Pro's save time optimizer highly enough - much less it's leaner footprint making it better suited to 'fast' work like cropping/resizing or even simple edits. Long runs of the same color horizontally, and repeating patterns vertically can both result in smaller images, so what colors are chosen for the palette reduction and how much dithering is applied can have an effect on the final size. This is why many programs often have more than one algorithm for determining the best colors (like PSP's median cuts vs. Octree) to do the color reduction with - as well as choices like 'ordered' and 'random' dither, and even things like interlaced vs. non-interlaced images. Interlaced doesn't just give you that 'progressive image load' thing, it can sometimes result in smaller files; Though it can also result in larger files - which is why you have to TEST. I think those of us who work with the image sizes a lot can all agree that it's just not as simple as 'pick one format' as they all have advantages and disadvantages. Which is the best advice - there are not hard fast rules... you can develop a few guidelines but sometimes the encoders of each format can 'surprise' you with results you don't expect... See some small (64x64 or smaller) 16 to 64 color linearts that actually save SMALLER as 24 bit .png than any other format because there's no palette information saved and the encoder handles the long vertical runs - or how sometimes if you MUST fit a file into a certain size the dithering of a .png or .gif ends up doing less damage than the artifacting from high jpeg compression... There is no easy answer... Test each image, use what gives you the best result from each... Oh, and 320k is not 'best result' if the image is going into your template.
It all depends on what the images are of. If there arent many colours, then you can use gif to save on sizd. In terms of quality .png are better but come at the cost of being more expensive in terms of size. jpgs are a happy medium
JPEG is the best format for general images and photos. No one can convince me that its quality is bad, unless you compress it lower than 60%. And when I need alpha channel I use PNG. It is really simple And GIF is terrible and outdated (come on, it was introduced in 80s).
Defiantly depends o nthe results your looking for. PNG if your designing website and want top results. .GIF if you want lower quality images but a high performance site. Really it all depend on your needs.
I use GIF for smaller images or images with not many colors. And then JPEG for larger images with a lot of different colors. Why not PNG? Because if you make a PNG on a Macintosh and then view it on a Windows machine, the colors are slightly off. It's very noticeable in a layout. On the same note, if you create the image on a Windows machine, it may look nice on the Windows machine, but on the Macintosh machine it's going to look bad. Also PNG isn't supported buy the older IE versions... Which I know many people still use (Maybe not a huge amount but enough to matter)
Please, disregard most of the answers here except for those who said "it depends". How can people say PNG (or whatever) is "best" in absolute terms?. The "best" image format is the one that displays correctly the image (real colors, no blurry, etc.) with the minimum file size. And that of course depends on each image. JPGs are usually better for photo-realistic images due to its compression algorithm, PNGs and GIFs identify better simple patrons (shapes), GIFs of course use less colors... but until you haven't optimized the image (reduced colors, compress, etc.) you won't know exactly the format that makes the image lighter without noticeable loss (though of course experience is a grade).
Hello, gif image is the best. because its a transparent image. you can used everywhere, but in another case PNG is also transparent and has more features then gif.
JPG - many colors (photos) PNG - few colors (up to 256), large image dimenshions, transparence GIF - few color (up to 256), small image dimenshions
Such are DP forums. I'm sure one or two learn from our posts, Javier, but few bother to read anything here.
It all depends on what you are using the images for, if its part of the design i would use GIF where i can reduce bandwidth and loading times, things like logos etc that you want to look good use PNG and for the rest use JPEG