Hi everyone. Save the Monster has all its graphic files in PNG. I love the quality of them, especially on the iPhone Retina display. But as there are currently 40 levels, with LOTS more to come, I can imagine the file size getting quite big. At the Moment the app download size is 40mb. If I converted all the level's background images (which are taking up the most MB's) to 80%Quality JPEG, I can get the file size of the app down to around 10MB. This would mean, for the time being, that the game can be downloaded over mobile network, instead of over wifi/computer. You can tell a SLIGHT difference in the image quality when looking close, my question is: Is it worth it? Worth giving up the images pixel perfect quality for file size (and maybe more downloads)? Thanks
If the difference is really SLIGHT & only when looking close, I would go with the JPG option... Specially as your game targets iPhone and it's smaller screen...
since you only need to be under 20mb, you can pick and choose. Keep the main hud and gui elements and game logo as png since they are seen more often. objects in motion can be jpeg since they aren't as closely scrutinized. also, be sure to check your audio settings since that can be another size hog. Tipatat www.gameface.me
Also look at how your PNGs are compressed. We are using Unity and were able to save lots of space and actually improve quality by compressing using PVRTex
If the game renders many objects at once, you might want to consider PNG since its quicker to process. I think JPEGs need to be uncompressed at runtime.
If the images don't require transparency, JPGs for sure! Trust me! You'll save a butt load on resources. As far as image quality, I can promise you that you won't be able to tell a difference on the device. If you really must go with PNGs, be sure to optimize them as PNG32s - same quality, smaller file size. In some cases, depending on how many colors you use, you can optimize it as PNG8 with transparency enabled. In that case you'll notice a slight difference in quality but it'll cut your file size up to 500%!
The other option is the PVRTC format I believe. I've toyed with it on backgrounds and it seems to render far faster and take up less space than PNG files.
I found if I used the export to web option in Illustrator, I could get png file sizes comparable to jpg, and still maintain top quality. There are similar options in Photoshop.
I'm only changing the backgrounds, so I don't need the transparency. Also I'd read that too, that for annimation, although you would think Jpeg, this apparently takes more to process...but then does png need to been uncomprssed too depending on how it's saved?
Well you've got a 50MB download limit to play with now. But I'd recommend to stay clear from .jpgs. Unless you save them out as high quality jpgs from photoshop then you'll be able to see the difference easily, especially on a retina display.