Sign in to follow this  
LuisFelizTirado

Misho: Photoshop to colorize Terraserver images

Recommended Posts

Misho I read one of your previous posts (long time ago) and you mentioned you had a good method for colorizing black and white imagery.Would you please share your process? I am using PS5.0 but you said you used PS6.0 and the menu items were somewhat different between the two versions. You said "auto contrast" which I converted to mean "auto levels" but in changing the red channels, my 24 bit B&W image remained without hues. If I check the "colorize" box the entire image is then colorized, but without good colors.Is there some way to take one of the default MS textures, extract its palette, then apply it to the Terraserver B&W images?How does this sound?1) You would first need to assemble a representative portion of default FS textures (we'll just take one for this example).2) Make note of the RGB values at each X,Y position on the bitmap3) convert the image to greyscale4) Note the greyscale 1-255 value of each pixel on the X,Y coordinateplane.5) Now you have a "dictionary" of greyscale values to RGB colors. This probably wouldn't fill up the whole 1-255 spectrum, but you could assemble a statistical dictionary by sampling more than one of the default 512x512 bitmaps until you have enough data for all the 1-255 values. (or you could interpolate)6) Simply translate each greyscale pixel using the equivalent RGB value.The only drawback I would see is that the palette would need to be shifted to allow for changes in brightness/contrast present in terraserver imagery. Or could not the auto-levels function of photoshop be used to "normalize" the color ranges? If anyone has any idea how to accomplish this task, please post below. Any help is appreciated!!!-Enrique

Share this post


Link to post
Share on other sites
Help AVSIM continue to serve you!
Please donate today!

Although it may seem as if this could work, It is not possible to do anything like you are suggesting. The thing is, every image has its own hue of terrain feature. Sometimes forests are dark and pastures light, sometimes vice-versa. Sometimes the water surfaces are white (reflection) sometimes pitch black. There is no way of standardizing what shade of gray will represent what color.The best way of doing this is to select "Color Range" and zero in on the particular feature, like forests and rocks. You can also use "wand" for this. Fortunately, landscape is surprisingly monochromatic (unless in urban areas) and you can usually get away with 3-4 shades of green, brown and blue (yes - blue, for certain rocks)When you select color range, you'll end up with a selection. You can use "expand" and "smooth" functions to get rid of the "sharpness" od the selection. Then, use "Adjust-Hue/Saturation-Colorize" setting and play with values. You'll be amazed what you can do with just a few simple colors. Check these out (Aspen Area, colorized from Terraserver imagery):Original TerraServer:http://www.terrabuilder.com/A1.jpgAnd the seasonal colorized versions:http://www.terrabuilder.com/A2.jpghttp://www.terrabuilder.com/A3.jpghttp://www.terrabuilder.com/A4.jpg

Share this post


Link to post
Share on other sites

Enrique, I have found some success with your initial idea, but with a twist, and its not perfect, there is some form of trial and error.Rather than try to analyse the grey scale per pixel, try this.1. Make a set of layers in a new image2. color one beige, one brown, one light green, one dark green3. adjust the underlying value by double clicking on each layer, and set that in properties for that layer. set the highest underlying value to the beige layer, like 190-240. That way bright white areas will resist browning.4. continue with this so that your greeny layers are for underlying values of 60-120ish....fool with these values, I find values below 60 to be of low impact.5 Set the transparency of each layer to 50%.Save this file, keep it for generic use in the future.Now take your b/w image and note the image size.Change the image size of your generic coloring image to match the b/w.Copy your b/w image into the color one as a new layer.sort the b/w layer down below the color layers, and you should see something decent. Adjust primarily by changing the underlying value within the color layers.You'll find portions of the b/w image will need brightness variation. Doing this will shift the color now, because of the underlying value connection. Once you get the color adjustment image to a place that you like, future projects get basic color in seconds. The only time it takes me to finish my image is to select the water and roads. The water I turn into an alpha, the roads I copy into a new layer all their own, which gives a greyish look to the roads.This is how I've been colorizing photos for years. You can see the results in my uploads, search on "bob bernstein". Good luck!B

Share this post


Link to post
Share on other sites

It is fascinating to see the different methods. Misho's results are very beautiful and I shall have to try Bob's very interesting system.I had the same idea as Enrique, and initially extracted the color tables directly from (FS2000) textures. Just load up the texture, IMAGE-MODE-COLOR TABLE, and save the table. Then, apply it to your image, IMAGE-MODE-COLOR TABLE-LOAD. Most did not give good results, but there were easily 6 to a dozen that looked pretty good, or provided a good basis for development.When applying a color table, it is essential to reduce the color depth of the original black and white image to indexed color using ADAPTIVE as the option.Later, I used a different method: reduce the color depth of the original image (indexed-adapative), then fiddle with Color Balance, adding and subtracting colors, until I get a good result.I then save the color table and apply it to other projects.This works reasonably well. Here is Chandeleur Island, off the coast of Louisiana:http://ftp.avsim.com/dcforum/User_files/3ddb8e647c84c90b.jpgAnd, Lake Havasu City, Arizona:http://ftp.avsim.com/dcforum/User_files/3ddb8ed47d666b41.jpgI hasten to add that I am using PhotoShop 5 LE (free with a printer, it does all I need.)Best regards.Luis

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this