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Bill Womack

Disappointed with Efforts Colouring Sat Photos

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Well I've tried colouring black and white satellite photos to use in FS but I'm disappointed with my efforts. They look too much like poor paintings rather than photographic scenery. I've been using Paint Shop and Photo Shop evaluation products. My method is by using several layers of different colours and varying the pixel something or other (!). I'm no expert with this sort of thing so I hope people know what I'm talking about!!!However, as far as I can see, unless you're an artist, I can't see how only using 3 or 4 colours can hope to truely represent the real world. Shouoldn't I be using 10 or more even in rural areas? However, the more layers the more time needed.Am I doing something wrong?

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Hi Victor,Don't be discouraged, mate. You're doing it right, it just takes a lonnnnnnggggg time to develop a technique and get the textures looking the way you want. I am a graphic designer and artist with 10+ years of experience in Photoshop, and I can tell you that it takes many, many hours of colorizing a black and white image before it looks truly convincing. If you have the time and can hang in there and experiment with it you may find that at some point you have a method of doing it that actually works for you. And yes, I'd say you should be using quite a few selective layers of colors; you can't expect it to look right with just 3 or 4. But it's mostly art and not so much science, so it might take a lot of trial and error before you like the results. Keep at it, bro. I feel your pain!thanks,

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A mate with 10 plus years of Photoshop experience. Just the person for this rookie to ask a FS/scenery question.In looking at the screen shots of "MegaScenery" I find that they have used 64934 unique colors. Now that just doesn't seem possible to convert a 255 gray scale to that many rgb colors. I am guessing that they work with a small number of unique f colors and then apply a blur - Gaussian, which, in my trials will create an image with a lot more uniques colors similar to what they have. IS THIS ASSUMPTION possible?2nd Question. In your experience, how many unique colors are needed for "presentable" grayscale to color conversion?3rd Question. Is it possible to generate a macro in PhotoShop to do the conversion? And lastly, in my little bit of playing, here is how I have been converting from grayscale to rgb in PhotoShop. Make a layer and color it with the color you wish to replace the grayscale with. Make a layer copy of the background (the grayscale image from terrraserver). Put this background copy layer above the replacement color. Turn off the background layer. On the background copy, use the color select and use the "picker" to select a gray that you wish to replace with the color in the layer you just created. Upon exiting the "color selection" hit the delete key. Now the "color layer" shows through where you selcted the grayscale. Merge down, and make a new replacemenst color and do it again... and again ... and agains.Easier way?Can anyone share Rosetta stones to convert from grayscale to rgb? Just looking at the large collection of images I have, I can see that one will not fit all. Images from a different time/source cast a very noticeable line where they joint. But maybe all that needs to be done is to slide the grayscale of the conversion palette?I do have "autoit" and I think I can put it to work doing all of this. ;-)Many thanks!BobSSeems the rage to talk about the "size and speed" of each others computer. Beat this if you can for solving novel/unique problems.. ..Have K&E and know how to use it!

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Ah the mysteries of the ages, part 26: how do they get those great color tiles from lowly black and white? Here's one little insight: if you create ground tiles as DXT1 bitmaps, the end result is 8-bit, regardless of where you started. You got it, that's 256 colors. So first of all, your working files can indeed be 8-bit, although you'll probably work in 24 bit mode in Photoshop and then convert to DXT1 at the end, so it's all academic. The technique you talk of for creating more colors with gaussian blur sounds interesting, but I'm not sure it's how I would approach it. After all, the resultant ground tiles will be so low-res already that you don't want to do anything that will soften the image whatsoever! To answer question 2, black and white images are always 256 colors, if they're true grayscale, so that's one less thing to worry about. If you've got a black and white for starters, then you've got 256 shades of gray to work with.Here's another way to approach the grayscale conversion conundrum: start with a black and white image and convert it to RGB in Photoshop. It'll still look black and white, but at least it will have three channels now, red green and blue. Then using the channels pane, adjust the brightness and contrast of each of the red, green and blue channels and the overall color will start shifting. You'll see the results if you also have the RGB channel turned on. It's similar to what you get with the "colorize" button in the Hue, Saturation and Brightness panel, but with finer control. Once you've gotten a base color set for your image, you can then go back to the layers and start picking out groups of tones and copying them to their own layer for colorizing. I cannot imagine how you could write an action to do it all from start to finish, but maybe that's just me... some enterprising soul might be able to do just that if they gave up having a life and devoted themselves to this problem. As for me, I'm happy to pluck away with a more labor-intensive hand process for now.thanks,

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Howdy,very nice summary, Bill - another post to be bookmarked ;-)Just a quick comment about this sentence:"In looking at the screen shots of "MegaScenery" I find that they have used 64934 unique colors. Now that just doesn't seem possible to convert a 255 gray scale to that many rgb colors."The Megascenery team didn't start with a grayscale image, they are using real-color IRS (Indian Remote Sensing) satellite imagery, and those are not cheap: http://www.intecamericas.com/IRS.htmCheers, Holger

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Yowsah! Man, I hope they either: a. Made a boatload of money on their MegaScenery packagesor b. Had a buddy that gave them a brother-in-law discount on the images!That's a big investment in a scenery project. I'll have to bookmark that site for after I win the lottery and begin giving away ridiculous amounts of scenery. ;-)

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Hi Bill,I'm not saying they bought from that particular company but there are only a few that process IRS data. In either case, they probably did have to plunk down a big chunk of cash up-front.Makes me wonder whether FS scenery designers could apply to the Bill Gates Foundation for grants? ;-)Cheers, Holger

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You might consider setting layers as you described but then adjust the background value for the layer with 50% transparency. You can get broad colorization that way, and then relegate the kind of work you suggested for fine tuning.Speed it up a bit, perhaps.Best,Bob Bernstein

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Thanks for the information.But, surely,(I know -- your name is not Shirley) you don't do each bitmap by hand do you? Several thousand bit maps would become a pain after 5.I just made layers for replacement of the gray scale colors in 15 unit increments from 1 to 255. I will make my own Rosetta Stone by taking MGS screenshots, duplicate each one in gray scale, develop masks using the gray scale image. Then pop this mask onto the color image and presto I should have a "stone" of grayscale vs. color replacement.Then using "autoit" I can save all the needed keystroke to color select, delete, merge down and then do it again using a different gray value each time --- from a saved file. The attachment is an example of where I am at. Regards,BobSSeems the rage to talk about the "size and speed" of each others computer. Beat this if you can for solving novel/unique problems.. ..Have K&E and know how to use it!

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Here's a technique I've used for my current project:http://www.windowlight.co.nz/wellington.htmlThe source image is a 2.5m/px image from the LINZ site, the online supplier of aerial imagery here in New Zealand. For the last two years they have begun producing colour images, but most is black and white. Wellington is the capital of New Zealand, with an international airport, but so far the major areas have not been covered in colour, and no doubt there are a lot of reasons why they won't be -- financial, mainly.The colour information does in fact come from an image from here:http://eol.jsc.nasa.gov/sseop/clickmap/The Gateway to Astronaut Photography.Most of the work is done in PhotoShop Elements. I've tried a few other applications, including my favourite, Picture Publisher, but none give the results I need. I would recommend this Elements to any scenery designer.I needed to browse through a lot of NASA images to get something suitable, but there are a few to choose from.The colour image is a lot lower resolution than the black and white, but this is not important. The idea is to combine the low resolution colour information with the high resolution black and white.I convert the bw to RGB, and paste the colour image into it. Using the transform tool (Ctrl-T) I rotate, distort enlarge, whatever it takes to get the two images aligned. Its easier to make the colour layer semi-transparent to get a good alignment. Because the colour image wasn't taken straight down there is a lot of distortion, so I actually needed to slice it up into smaller areas and transfrom each one individually.Once I get the images aligned, I convert the layer Blend Mode to Colour. (Layer: Layer Style: Blend mode, or just from the layer rollout.)The leave the colour layer active to make colour adjustments, as this will leave the background intact -- preserving the sharpness.The astronaut photos are normally very blue, so some quite serious adjusting needs to be done. I also need to reduce the saturation a bit as well. Some touching up with the clone brush can fix obvious holes -- you can get some strange effects if the two images are taken years apart!PhotoShop's Colour mode tends to preserve the saturation as well, whereas Picture Publisher doesn't, which is why Elements (or photoshop itself) is the only real choice here.Once the colour adjustment is finished, I Merge the layer and do any sharpening and tonal adjustments. The secret to good aerial imagery is this:All adjustments to an image reduce the quality, so minimal adjustments give the best result. Here I only work on the colour information for most of the time, so that the original image, which supplies the detail and sharpness, is preserved. This goes for any image, though, even if you start with the perfect colour image, don't mess with it too much!The Unsharp mask should be used to give a bit more sharpness than normal. You'll know when you overdo it, but a sharp image gives crisp textures.If there was enough interest in this technique, I could create a tutorial on my site. Let me know.

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I just do several bmps. One for each season, one for night. Big ones....100s of mbs each. Then slice them once colored.B

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Thanks guys for the great tips. The one about using a BIG file will save the day. I had thought I needed to do one terraserver image at a time. Then I recalled the program by Cox that will build a real big image from the terraserver data. I got one over 8mb and discovered my 1.2ghz machine will take a little time to do anything to the image such as repalcing colors. But it will do it. And it is better to issue a 'few' commands and wait in between them then it is to issue a lot of commands and have the puter waiting on me. Thanks again for that big file tip. ;-)Keep in mind I have zero artist skills AND my monitor is in need of replacement. Now days it is very washed out and very low in contrast. Yes, I have fiddled with the controls and still can not get it back. But that is not this is about.Keeping the two facts above in mind, I needed some way to convert from a grayscale image to a colored image using a defined method instead of an artist touch. Using the method I am developing, if we all started with the same gray scale image, all our results would be identical. Defined method exact method.But are the results worth keeping? I am not sure beings I don't have an artists eye and my monitor is challenged.http://forums.avsim.net/user_files/72180.jpgSo could I ask you all to comment on the attached image. For best viewing and rating, I placed a jpg that has not been converted to an 800 pixel width and a file file size less then 120kb. Look at a full size 800kb image here:http://s95171098.onlinehome.us/st.zipThe grayscale image came from terraserver and is a view of central Illinois.If this is good enough, I will be happy to share this "by the numbers" mechanical method with all who need it. Artists probably will not be interested. ;-)Using "autoit" i will be able to build a macro that does all the needed steps. Then we can build our own MegaScenery where ever we wish -- for nothing. Anyone interested in building Illinois and adjacent states that has a working knowledge of PS version 5 or later interested?We r rsam@mtco.comRegards,BobSSeems the rage to talk about the "size and speed" of each others computer. Beat this if you can for solving novel/unique problems.. ..Have K&E and know how to use it!

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That looks pretty good, Sam, especially for a formula-based approach to conversion. Does it blend in pretty well with the surrounding default terrain? I'd say you've got a decent technique in the works.thanks,

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Hello Bob,You have gotten great results! It looks very, very good.You might be disappointed, however, if you try to apply your method to all gray-scale, USGS aerial images. Different parts of the U.S. have different gray-scale values, so your method might work in one region, but give very different results in another. Perhaps you might try it out first on another part of the U.S. and see how it turns out.Best regards.Luis

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Thanks for the comments Bill and Luis.I created my 15 color replacement palette by making a screen print from the overhead view in FS9 (ctl S). This assured me that the colors will blend into the standard FS9 scenery. I also used the Guassian blur to slightly (.3 dia) smooth the colors between pixels.If I was doing New Mexico, I would build my rosetta color palette from a screeshot from overhead in that region in FS9. It would still be all by "mechanical" methods and we should all get the same results.I only used 15 grayscale to color increments. I made them all 15 units in size. 1-15, 16-30, ... 240-255. I may want to increase the number of increments. I could probably increase the size of the increments close to each end. Not much happens close to the ends of the grayscale. I probably could use more defination in the middle range of the grayscale.It does seem to work in general well enough to continue with it. Water will have to be handled probably with the magic wand. Hand/artist work. :-(I think for the Fall and Winter coloring, all I will have to do is grab a new screen shot from FS9, (ctl s), durning winter/fall and build a new grayscale rosetta stone/palette.This does appear to allow non-talented people like me to convert grayscale images from terraservet to colored images for FS9. Not as good as an artist, but good.Regards,BobSSeems the rage to talk about the "size and speed" of each others computer. Beat this if you can for solving novel/unique problems.. ..Have K&E and know how to use it!

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Hi Bob (don't know where I got "Sam" from, sorry),I don't think I'd depend on top-down screenshots from FS for getting a match on the colors. A better method would be to identify which textures are being used for the landclass you're viewing, find that texture in FS and make a 24-bit converted copy for use in your image editor. That'll give you a version of the texture that's not affecting by terrain and lighting, thus a much better absolute image to match. The textures can be matched to their landclass counterparts partially by using the terrain texture names doc in the FS2002 (I think) terrain SDK. Of course, it's only a partial match so you might want to copy all of your FS textures into a new folder and convert them all to 24-bit and then view them using the thumbnail view in your folder options to see which ones appear to correspond to the landclasses in question. It's a little time consuming, but I'll bet you like the results better.thanks,

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looking good, Bob. Only comment to add is that spacing your grey scale values out equally may not be the most effective use of colors, I guess I'm only saying this from experience with the usgs terraserver black and white images. I found huge ranges of grey scale were hardly represented at all within the image, and then sometimes seperation of only a few grey scale values produced good effects to be sperated in color.Just refinement concepts....your results look fine. It just might mean you aren't really seeing all the colors.Bob Bernstein

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