[http://sourceforge.net/p/ufoai/patches/531 Item 531] imported from sourceforge.net tracker on 2013-01-28 20:43:43

There is a lot of unnecessary information attached to many of our jpgs especially in the models/soldiers folder, but also in other folders. We can save a lot of space & optimize loading times by stripping this information from the files...
Here is an example what that would meann filesizewise (this is just the soldiers/female folder):
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Date: Mittwoch, 28. April 2010
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\body.jpg
No changes necessary
18.078 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\body_arctic.jpg
No changes necessary
68.186 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\body_cccp.jpg
No changes necessary
50.551 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\body_desert.jpg
No changes necessary
17.618 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\body_jungle.jpg
No changes necessary
17.814 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\body_yellow.jpg
No changes necessary
31.768 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\head01.jpg
No changes necessary
5.504 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\head01b.jpg
No changes necessary
9.253 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\head01b_arctic.jpg
No changes necessary
9.314 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\head01b_desert.jpg
No changes necessary
9.105 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\head01b_jungle.jpg
No changes necessary
9.327 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\head01b_urban.jpg
No changes necessary
9.201 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\head01_arctic.jpg
No changes necessary
8.916 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\head01_desert.jpg
No changes necessary
7.016 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\head01_jungle.jpg
No changes necessary
7.199 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\head01_urban.jpg
No changes necessary
7.105 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\head02.jpg
No changes necessary
11.340 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\head02_arctic.jpg
No changes necessary
12.784 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\head02_desert.jpg
No changes necessary
10.788 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\head02_jungle.jpg
No changes necessary
10.904 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\head02_urban.jpg
No changes necessary
10.767 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\head03.jpg
No changes necessary
14.453 bytes
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C:\UFOAI-2.3-dev\base\models.orig\soldiers\female\Strip\head04.jpg
No changes necessary
7.434 bytes
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23 Total files processed
0 Files renamed
0 Files successfully processed
0 Errors
23 Files needed no changes
364.425 Bytes processed
0 Bytes saved

Elapsed Time: 00:00:00

This reduced filesize for that folder from 1.38MB to 1.24MB without changing anything (!) in-game just by stripping unnecessary exif, xmp & iptc tags from the files...
There is no patch attached yet. Waiting for a 'Go for it.'

We could also reduce filesizes & loading times dramatically if we change the color palettes of many of the textures, which do not need that many colors...
I am currently searching for a tool which is able to convert pngs not only to 1, 2, 4, 8, 24 & 48 bit, but also to 12 bit (4096 colors) & 16 bit (65536 colors).
That would allow us to use high-quality lossless png textures with smaller sizes than our current artifacts riddled jpgs...
But for many of the textures even 8 bit (256 colors) would be enough, although 256 colors are really not much, that is why I think 12 & 16 bit would be ideal for many of our textures...
If someone knows a tool that can create 12 or 16 bit pngs, please shout out loud here !
===== Comments Ported from Sourceforge =====

====== mcr2010 (2010-04-28 08:16:43) ======

I need just a 'Yes' or 'No' here (for stripping jpg tags), so I will set the priority rather to high...
====== tlh2000 (2010-04-28 09:58:16) ======

loading times != file size - if we use palettized images we will in fact increase the loading times, as they must be converted into the opengl image format (32bit rgba in most of the cases)
====== tlh2000 (2010-04-28 10:07:24) ======

removing exif and co should be possible with imagemagicks
====== mcr2010 (2010-04-28 10:10:45) ======

Sorry, but filesize=loading times. & 2+2=4 not 5, I know that for sure... ;)

Another thing is the conversation afterwards. I do not know how long this takes & have not thought about that. So I will stay with rgba 32 bit.

Again I made the mistake & put two different things in one request.
What about the unnecessary tags ?
I see you answered that one already.
====== tlh2000 (2010-04-28 19:29:41) ======

ok - i'm counting the conversion to the final format we need it in to the loading time. if you don't, then you are right, but having a palettized image in the memory doesn't help us :-P

the exif headers are now all removed btw. - that's why i close this, thanks a lot for pointing this out.