Why JPG not supported?

[stuh505]

I'm just curious, because BMP take up so much more space, why JPG format isn't supported.  I'm looking at 60 MB of background images alone...

[Joe]

im curious too.  each room background takes up 750 k in my game at 640x400 pixels.  

[InCreator]

quality maybe? JPEG looks best with photos, but drawings seem somewhat blurry.

[strazer]

Isn't this in the FAQ?
JPGs will not be supported, because it is a LOSSY format.
Also, it doesn't matter what format the pics are in when you import them.
AGS automatically compresses backgrounds in its own format. Sprites are stored uncompressed either way for performance reasons.

Use PNG if you want to save hard disk space...

[stuh505]

Thanks for the explanation strazer.


However, on the subject of JPGs...

Blurry?  Lousy?  What are you guys smoking!?

Sure, if you select save as JPG from paint it looks like sh*t...but from Photoshop, I have never been able to discern even a slight loss of image quality over BMP...

In fact, I have just performed a small test.  I rendered a 3d image with some complex reflections and radiosity straight to BMP form (ie its a pure image, wasn't converted to bmp from something else), then I resaved it as a JPG and compared the two close up.  Guess what?  Every pixel has the exact identical tone and shade.  Not the slightest difference whatsoever.

[Robert Eric]

stuh505, JPEG has different encoding and compression options that you can set.  Most image editing programs have them preset to standard, but can be changed easily.

[Hollister Man]

If you save at the highest image quality settings, you don't really get much benefit over other file formats.  The "kicker" for JPEG on the 'net is the fact that it can cause such high compression rates without significant loss of quality.  On today's computers, that isn't such a big issue (so what if you have a couple of megs of images, burn 'em to CD and toss 'em in a drawer if they're too annoying. )

[stuh505]

Okay.

Well continuing my experiment further...

At maximum JPG quality, the BMP is still 3.34 times larger.  

At medium JPG quality, the BMP is 7.28 times larger.  There is very slight difference, but it is not visible to my naked eye with full magnification.

Below medium, quality goes downhill in a hurry.

[Gilbert]

It's been discussed many times already.

Because the backgrounds in room files are all compressed by some lossless scheme, no matter what format of images you're using for import the resulting file size of the room is still the same. So there're no advantage in using JPEG at the time being, and moreover JPEG compression is lossy (unless of course the room files can also store lossily native JPEG compressed images as bg, which is not implemented at the moment).

So using different image formats only affect your working files not the resultant filesize. If you're really low on HDD space, just save your working files as PCXs and PNGs.