How can I convert an image's pixels to actual LEGO colors?

Question

The LEGO Group released a few "mosaic" sets a while back, which came with clear baseplates and a bunch of 1x1 bricks. I have been wondering recently if it is possible to use an image as a reference when building one of these.

Unfortunately, this is hard because digital images can have a lot more colors than there are actual LEGO colors.

I am not interested in anything more than 1x1 bricks on a baseplate, regardless of the fact that the image has some other bricks added onto those 1x1s. The scenes which I would be interested in building would effectively be two-dimensional.

Is there perhaps a way (besides approximating) to change the pixels of an image into actual LEGO colors? Is there perhaps some type of web-application for this?

Related: How many different colours of LEGO bricks are there?

Answer 1

You can use GIMP for this. First you need to scale the image to the size you want. (If you want to stack bricks on top of each other instead of a baseplate, use a different y-scaling to correspond the bricks height.)

Now create a palette by going to the Palette tab and click the "New palette" icon.

In this add the bricks colors you want. You can find the colors RGB values to a brick color here: http://www.peeron.com/cgi-bin/invcgis/colorguide.cgi

Now convert into these colors by going to "Image->Mode->Indexed...". (If indexed is already selected, select RGB first and then click Indexed.) A "Convert Image to Indexed Colors" dialog box should appear.

Select "Use custom palette" and select the palette you just created.

Click "Convert" to get your result. If you are not quite satisfied, click undo and try to change/add some colors in your custom palette and convert again.

Answer 2

You can also use the web-based Mosaic Maker.

Answer 3

Similar to 'Mosaic Maker' suggested by @Conrado PLG , there is 'Bricksaic' from Bong 69 Productions.

From their website:

A program used to make Lego Mosaics. You choose the image, the stud width and the type of bricks to use and you instantly have an LDraw file to make the mosaic from.

I have used the software myself and found it to be complete and functional with lots of nice options. It seems to do exactly what you are asking for by taking a digital image, and creating a 'LEGO map' of parts using only the colours that you specify. (The choice of colours being only actual LEGO colours).

Feature list (from their website):

• Choose the image
• Choose the stud width of the mosaic
• Choose from 7 different Dithering routines
• Use up to 41 colors in the color palette
• Makes an LDraw file
• Prints a color map
• Loads and Ldraw file made with Bricksaic
• Choose to use plates or bricks and studs up or studs out from these selections: 1x Plates - studs up 2x Plates - studs up (2 studs thick) 1x Bricks - studs up 2x Bricks - studs up (2 studs thick) 1x Plates - studs out 2x Plates - studs out 1x Bricks - studs out 2x Bricks - studs out

Answer 4

On the Mac you can use an app called Digital ColorMeter, whcih is built into the Mac by default. The app can be used to parse out colors on a screen base on their R G B ratings, so you can just hover the mouse over a picture of a lego brick for a semi-accurate rating if the photo is good. If you have a program that can generate colors based on the R G B ratings of colors you could use the color, or you could install Hex Color Picker and enter the HTML color-codes into the Mac color picker if you can get the color codes with a certain program.

Hope this helped. :)