How to quickly color correct raw sattelite images?

[fsxjunkie]

How do I quickly color correct raw sattelite images?

Just something universal and basic.

Thanks!

 

[fsxjunkie]

***Removed***

 

[scott967]

I don't think you will find anything universal and basic, but what I have done is play with the color curves in GIMP. There is a program out there called "PureImage" that can do some auto color correction that you might want to look for. You can compare two images and it will use one as the basis for correcting the other.

scott s.
.

 

[rhumbaflappy]

I found 2 semi-automatic ways to color match one image to another'scolor scheme.

If you have access to Photoshop or Paint Shop Pro, you can add a plug-in:

Metrix

The instructions with the plug-in is a bit sketchy....

You open the satellite or aerial image, then you open the color template image.

The template image could be derived from one of the default landclass textures... choose one in use where your photoreal will be located. This way, your re-colored image will match the color of the surrounding landclass tiles. Use Imagetool to extract the template images.

I use a batch file for this:

imagetool -tga -32 -nomip *.bmp
pause

Place your template files in a new folder, along with the 'convert.bat' shown above, and Imagetool from the SDK. The template files would be representative of the type of LC texture files you see in the area. Don't use a top-down screenshot from FSX, as this will have time-of-day color adjustment and terrain mesh distortion. Then run the BAT file by double-clicking it.



In Photoshop or Paint Shop Pro...

Select the template image, run Metrix from the effects menu, then mark the 'Analyze' radio button and press OK.

Select the target image, run Metrix from the effects menu, then mark the 'Apply' radio button and press OK... and wait a few seconds. Soon the photoreal target will be colored much like the default landclass tiles.

Save the re-colored file with a representative name as a BMP or Tiff or TGA.

I'd make one for each season used in your area... for my area, I have HardWinter, Spring Summer and Fall ( no Winter ). You could also try LM, but the results probably won't be right.

For C59 ( Delavan, Wisconsin, USA ) I used 007b2hw7.bmp, 007b2sp7.bmp,
007b2su7.bmp, 007b2fa7.bmp, 007b2lm7.bmp, as my templates, and applied them to a BMP file I got from SBuilderX313, to get each season.

I made a blend mask by painting white over what I wanted to keep, and coloring the masked as black, and converting to greyscale, and saving as 8-bit tif.

My 'C59_Photoreal.INF':

[Source]
Type = MultiSource
NumberOfSources = 6

[Source1]
   Type = BMP
   Layer = Imagery
   SourceDir = "."
   SourceFile = "L18X133106X133113Y193362Y193389_hw.BMP"
   Variation = January, February, March, November, December
   NullValue = 255,255,255
   ulyMap =  42.6410305916549
   ulxMap = -88.6033630371094
   xDim =  2.68220901489258E-06
   yDim =  1.9732898504436E-06
   Channel_BlendMask = 6.0

[Source2]
   Type = BMP
   Layer = Imagery
   SourceDir = "."
   SourceFile = "L18X133106X133113Y193362Y193389_sp.BMP"
   Variation = April, May
   NullValue = 255,255,255
   ulyMap =  42.6410305916549
   ulxMap = -88.6033630371094
   xDim =  2.68220901489258E-06
   yDim =  1.9732898504436E-06
   Channel_BlendMask = 6.0

[Source3]
   Type = BMP
   Layer = Imagery
   SourceDir = "."
   SourceFile = "L18X133106X133113Y193362Y193389_su.BMP"
   Variation = June, July, August
   NullValue = 255,255,255
   ulyMap =  42.6410305916549
   ulxMap = -88.6033630371094
   xDim =  2.68220901489258E-06
   yDim =  1.9732898504436E-06
   Channel_BlendMask = 6.0

[Source4]
   Type = BMP
   Layer = Imagery
   SourceDir = "."
   SourceFile = "L18X133106X133113Y193362Y193389_fa.BMP"
   Variation = September, October
   NullValue = 255,255,255
   ulyMap =  42.6410305916549
   ulxMap = -88.6033630371094
   xDim =  2.68220901489258E-06
   yDim =  1.9732898504436E-06
   Channel_BlendMask = 6.0

[Source5]
   Type = BMP
   Layer = Imagery
   SourceDir = "."
   SourceFile = "L18X133106X133113Y193362Y193389_lm.BMP"
   Variation = Night
   NullValue = 255,255,255
   ulyMap =  42.6410305916549
   ulxMap = -88.6033630371094
   xDim =  2.68220901489258E-06
   yDim =  1.9732898504436E-06
   Channel_BlendMask = 6.0

[Source6]
   Type = TIFF
   Layer = None
   SourceDir = "."
   SourceFile = "L18X133106X133113Y193362Y193389_B.tif"
   NullValue = 255,255,255
   SamplingMethod = Gaussian
   ulyMap =  42.6410305916549
   ulxMap = -88.6033630371094
   xDim =  2.68220901489258E-06
   yDim =  1.9732898504436E-06

[Destination]
   DestDir = "."
   DestBaseFileName = "C59"
   DestFileType = BGL
   LOD = Auto
   UseSourceDimensions = 1
   CompressionQuality = 85

++++++++++++++++++++

Another option is to download and install PaintDotNet, a very nice freeware paint program:

PaintDotNet

There is then a plug-in for this :

pyrochild plugins

ColorMatch is the name of the plug-in used.

The results look identical to the Photoshop/psp plugin.

I belive newer versions of Photoshop and PSP may have the color matching function built-in as a default effect, but I'm not sure.

I need to do a bit of work in ADE, but the image looks pretty good.

Dick

 

[PakMac]

Dick - Thanks for such an informative tutorial on color matching.

David

 

[fsxjunkie]

Wow! Thanks very much for that! Now I can match hard winter and all the other seasons.


Thanks!

 

[falcon409]

Dick,

One question on the hard winter shot you have. I tried several top down shots to use as templates to get a good variation in the whites for the photoreal scenery. To be honest, I got nothing that is saturated with color like you show in your shot. Basically, what Metrix does is to lighten the selected area to attempt to match the general white card appearance, but as far as variations in that white it won't do that. So what else did you have to do to get the correct match for winter? Other seasons are simple really, but hard winter is not.

 

[fsxjunkie]

I am having trouble installing the plugin. When I put it in my plugin folder, it doesn't show up anywhere. Where do I access the plug in? Where do I install it?

Sorry for the noob question, lol

 

[GHD]

Hi Dick,

That is a superb way to colour correct

I have successfully installed metrix into Paint Shop Pro 7, but can you please tell me how to associate the landclass texture names with a particular geographic area?

 

[rhumbaflappy]

Ok

Hi falcon409.

For templates I extracted the 1024x1024 image from the landclass textures. In this case I used 007b2hw7.tga, extracted/saved by Imagetool from the default 007b2hw7.bmp Using topdown screenshots doesn't work well, as seasonal and time-of-day sun position colors the landscape, and terrain interferes.

I haven't tried many examples, so it may be that HW will cause problems, and may need a bit more work, but my airport looked OK.


Hi Golf-HotelDelta.

I took the lat-long position of the center of the runway from TCalcX, and used those positions in TMFViewer to center the viewport in that app.

I then checked Seasons.bgl to see just what months were what season in FSX for that location... needed to figure out the INF and seasonal varuiation of the template textures. Now I knew the months for su, sp, fa, wi, and hw ( and in this case, no wi used at all ).

I then checked the worldLC.bgl to see what landclass values were in this area. I found 117, 55, 35, and 30... with 117 and 30 most common, and 30 being more like the real-world LC.

Settling on LC #30, I needed to find the actual texture naming. I used Holger Sandmann's spreadsheet for this:

HS_FSX_Land_Class_Table_v2

This gave me the texture set named like "007b2su1.bmp" ( "B" is my USA region, and that can also be found by TMFViewer ). I looked at the seven variations of that texture, and selected 007b2su7.bmp, and it's seasonal brothers, as most like my photoreal target.

Luis Feliz-Tirado is thinking of uploading a similar spreadsheet to AVSIM in the future... it has all regions I believe.


Hi fsxjunkie.

What paint program are you using?

In PaintShopPro 8, the Metrix plug-in ( Metrix.8bf ) is placed in "...\Jasc Software Inc\Paint Shop Pro 8\PlugIns\MetrixForPhotoShop\" folder. I would guess the location would be similar for PhotoShop.

Dick

 

[GHD]

Thanks for the details Dick.

As I usually deal only with photographic textures I have no experience with landclass, worldlc.bgl together with TmfViewer provided the clue.

 

[rhumbaflappy]

The problem is aerial imagery usually doesn't match the color schemes of the default landclass. This color "correction" allows the photoreal to blend very well into the default landclass bordering the photoreal area, instead of the abrupt change we usually get.

The FSX resample blendmask allows for edge blending, but the color change is still very noticable without trying to match the default color scheme.

You can load FSX resampled photoreal into TMFViewer to check masks and seasons as well.

Dick

 

[rhumbaflappy]

Hi falcon409.

The hard winter textures do present more problems. I first killed the color by reducing the saturation to 0. I then tried making the roads black via a magic wand selection. Then a little lightening, come added contrast, and then sepia toning.

Then I used the Metrix color matching.


It came out pretty good.

For the other seasons, I adjusted the gamma upwards a bit as the whole image was a bit dark.

Fall also would present challenges... but I'm sure a process could be developed to make adjustments in a systematic way... maybe a scripted way.

Dick

 

[bertvk]

Thanks Dick for the very clear and helpfull tutorial.

Regards
Bert

 

[rhumbaflappy]

Hi all.

Something closer to what we need has been researched:

Using Image Analogies for Rapid Generation of Terrain for Simulations

image-analogies

A paper sponsored by Microsoft

A small explanation by A. Hertzmann

It would be nice to have some updated code and maybe done in a vb.net or c# environment.

If you want to waste a day on this, try googling:

image analogies

or

color transfer between images

This one is very teasing, but has no concrete program for us:

http://www.scirp.org/Journal/PaperDownload.aspx?paperID=546&fileName=JILSA20090100003_93148972.pdf


Dick

 

[nzeddy]

Sorry for posting in a old topic but does anyone know if you can do this with GIMP 2.6?

EDIT: Nevermind.

 

[GaryGB]

IMHO, this is one of several topics which (...like some participants in the FS Development Community ) -is unlikely to ever be so old as to no longer be pertinent and/or unable to contribute something meaningful to the FS knowledge base regarding FS terrain texture development processes.


IIUC, this thread ("more than 1008 days old" as I write and post this ! ) discusses resources which we might use to more easily achieve texture compatibility between texture sets used in FS, and IMO is particularly relevant to creating and blending the visual component of custom photo-realistic textures used on ground polys and land class polygons and/or tiles into surrounding terrain textures from FS default or 3rd party custom terrain textures.



I was reminded of this valuable FS knowledge base resource as a result of a recent thread here at FS Developer:

http://www.fsdeveloper.com/forum/showthread.php?t=427174


[EDITED]

IMHO, the OP in the above linked thread indirectly posed a vaguely defined problem scenario within a "mixed content message", which worded otherwise could have stimulated an informative, productive, and helpful exploration of how to implement custom photo-realistic textures in terrain scenery design, when a target for ones own custom scenery content has textures that are either FS default or even custom 3rd party (...both of which will likely have a "color palette" different from our own custom terrain texture content). :spushpin:



Those FS developers who have previously worked with making custom photo-real textures for FS (AFAIK, including the OP in the above linked thread ! ) know that each aerial imagery source may have its own "color palette" due to variations of color attributes between its raster tiles, which we may be compelled to correct for consistency as a working data set.


We may also opt to further modify a copy of a "color-matched" custom photo-real work set of texture tiles, so that its color attributes are more consistent with a target FS installation configuration of existing textures which are either FS default ...or 3rd party custom textures, such as FTX "Regions" (like 'PNW'), FTX Global (aka "FTXG"), or Ground Environment X (aka "GEX")

Again, both of the above cited packages and FS itself ...will likely have a "color palette" different from our own custom terrain texture content, and may compel correction with a graphics application for consistency when blended into the surrounding terrain textures in ones target FS ground texture configuration scenario.

[END_EDIT]



FYI: I believe there may now be some resources to graphically process textures available for ex: color matching, that are newer than those already mentioned in this thread, which IMO, merit mention here.


To assist with graphically editing our raster data set of aerial imagery we might also consider using some of the ideas 'linked' below which may apply to graphics programs popular with FS "developers":

GIMP:

http://www.google.com/#bav=on.2,or.r_qf.&fp=2dadce597fc84e2&psj=1&q=color+match+GIMP



Photoshop:

http://www.google.com/#bav=on.2,or.r_qf.&fp=2dadce597fc84e2&psj=1&q=color+match+Photoshop




BTW: The "Metrix" plugin referenced earlier in this thread reportedly can now be used in numerous other graphics applications:

"Metrix, first released in 2000, automatically matches the color distribution
of any image or selection to any other. It is widely used in over 100
countries around the world. Metrix is used for ordinary snapshot
photography, panoramas, stereoscopic photography, cartography, medical and
scientific imaging, virtual reality, and fine art photo compositing.

Although Adobe added a "Match Color" function to Photoshop in 2004, Metrix's
color-matching is more accurate and easier to use. Please see the Metrix
Acid Test page at http://jnrubin.net/psi/test.html.

In addition to Adobe Photoshop, Metrix can be used with any Windows program
that hosts Photoshop plug-ins, including Photoshop Elements, Illustrator,
After Effects, CorelDRAW!, Paint Shop Pro, and Freehand. It can also be used
with certain versions of 3D Max, Bryce, Canvas, Combustion, Deep Paint,
Digital Image Pro, Fireworks, GIMP, HyperStudio, imageN, IrfanView,
Microsoft Expression, Painter, Photo House, PhotoBrush, PhotoDeluxe,
PhotoDraw, PhotoExpress, PhotoImpact, Photoline, PhotoPaint, PhotoPlus,
Picture Publisher, Plugin Commander Light, Plugin Commander Pro, QFX/LE,
Serif PhotoPlus, SigmaPi NiGulp, Ultimate FX, Ultimate Paint, VCW Vicman's
Photo Editor, and XnView."

https://groups.google.com/forum/#!topic/comp.graphics.apps.photoshop/C_HP7dexOu4


Hope this updated and supplemental information helps !

GaryGB

 

[2wheelsup]

Hi
I just located this old excellent thread after many hours of searching for color matching.
Is there another link for Holger Sandmann's spreadsheet. It appears the link in question is no longer valid.

Thanks,
Alan

 

[JRobinson]

I think this is the one you want (link in post):

http://www.fsdeveloper.com/forum/threads/landclass-blending.433181/#post-701886

 

[2wheelsup]

I think this is the one you want (link in post):

http://www.fsdeveloper.com/forum/threads/landclass-blending.433181/#post-701886

Thanks JR. Just what I was looking for.
Alan