Creating a Mosaic
A master image composed of many smaller and different images
History:
A mosaic can be a composite picture made of overlapping, usually hard-copy aerial photographs. A mosaic during the early Greek period was also many stones laid on the ground to create a picture on a cobble stone road. These are not what we are doing in this tutorial. In this instance a Mosaic is defined as many smaller digital photographs. When you zoom-outward the many smaller images resemble one larger and completely different master-image. This document should give you some advanced insights and thereby streamline your project. At the bottom of the page is a listing of the free software used to do this.
1) Go straight to Andrea-Mosaic tutorial
2) Go straight to Foto-Mosaik tutorial
3) Go to video and let me demonstrate first
Mosaic of a humming bird done with Andrea-mosaic and original photo taken by me during a summer cook-out
Gathering the Collection Images:
In a basic overview, you choose one master-image and the program goes through your collection to draw this master-image with your other images. Start out by gathering as many images as you can of the subject you are interested in. The more images the better. Your master image may need complex shapes and the mosaic program will require all those shapes and colors to create your larger image. Maybe your master image will be simple and a great many images won't be needed? That is your choice and probably a good idea for your first practice. Place all of the collection images into a single folder. I recommend always using a copy of your images rather than the originals.
Let's say a master-image was a green mountain with a very blue sky. The computer will check the collection for blue images for use as the sky and green for the mountain. If none of the needed images are present for the master-image, then it will not look much like the original. If the collection is composed of many pictures with people boating down a dark blue river, then the program will use these to populate the blue sky portion of the master-image. Of course the sky may then be a dark river blue rather than a light blue but the sky is created in this way. So the more, diverse, and closely color matched pictures the better. I made one of my wife and me not long ago. There were no images in my collection of our skin tones. The computer picked red images which were warm colored but not exact. To be honest it looked as if the mosaic had a bloody-nose due to the color being too red in the head area.
Some of your images are probably upright like portraits and others are elongated like landscapes. Add to this the issues of image sizes in your collection. With mega-pixel cameras these are getting huge. The various programs deal with orientation and sizing in different ways. Some programs put the reformatting and resizing on you. If the images require resizing by you then you may see gaps between the tiles as in the example below done with PhotoTile. The problem was my resizing software and how it didn't have cropping ability at the time. Better programs resize and rotate your images automatically to make them fit best into the master image. The free programs I recommend below allow for resizing and rotation automatically which works out great and looks seamless. What's the down side to rotation? If the images are rotated then you have to turn your neck to see them in the final mosaic. This is an acceptable trade-off. I'm not sure I like the flip upside-down option but sideways is fine.
Theme considerations:
When it comes to a theme you may want to think ahead. If your master image is a flower then perhaps all the sub-images should be flowers as well? This way as the viewer finds out what the picture is made of they can see a running theme you have designed. Notice in the image below I took a Venus statue snapshot in Paris France for my original. For the sub-images I chose only family shots. Since going to Paris was a family trip this is a fitting theme for me.
Examples:
Notice in my example below that the algorithm (or math done by the computer program) chose a "Baby's Ultrasound" for the right-eye of the statue. This seems strange at first but when you squint your eyes, it is exactly the shading and shape you'd expect in the master image. A version of this Venus is a huge poster hanging on my wall at home. Making it large allows me to see each of the smaller images with all the best quality and even better than you see here. Alright, at the time I made the Phototile mosaic I wan't all that savy on how to batch-process tons of images and have then croppred properly. This just goes to show that resizing is best when done by the program in question.
Phototile version but the mandatory resizing of photos to 640x480 created unwanted gaps between tiles.
Resolution considerations:
Have you ever noticed that you can take a picture by zooming into something for extreme detail or you can zoom out and get a nice overview? You really can't do both at the same time usually can you? This is a standard imagery limitation. If you want the smaller pictures to be clear, then your master image is going to be really large. The main point of a mosaic is probably to have the viewer get interested in zooming in just to check out your smaller pictures, right? The difficult part I'm mentioning is the balance between super detail and having little blurry images no one cares about. The resolution will of course depend on what you plan on doing with the mosaic when completed. For computer wallpaper you can keep it relatively small and for printing, larger is better. The examples below have been formatted into larger and smaller clips so you can get a feel for what I mean.
click to see larger PhotoTile version of image
Building the Collection:
Building a collection can be the most tedious part of a robust mosaic. The Venus poster I created ended up at a very high resolution (because I planned on printing it big) at some 275MB. The one above was Phototile but the poster version I made was with the program provided below. Most of your creations will be much smaller probably. My recommendation is to put a copy of all of your images or clip-art into one directory (folder) before building a "collection" for your mosaic.
One important note is that once the collection is made then that collection is summarized in a small file that keeps track of all your images. In other words the collection file is the mosaic software's database. Why does that matter? Let us say I made my Venus mosaic and my software chose a donkey for the nose each time I made that particular image. I decide this isn't what I want and it is not attractive. I then go into the picture collection and delete the original donkey image as an attempted solution. However, in the database file it has kept track of the donkey image and will now error or place a black rectangle where the donkey image was. In other words the collection will have to be regenerated for accuracy if any changes are made to the images.
I poured all of my family album images into one directory for use in making a mosaic. This taught me that when one gets above 10,000 images the "collection" phase will take a bit of time. When you build your collection it is creating that reference database for the program to do calculations.
Freeware Mosaic Programs:
What program can I use to make one of these mosaics? There are many. For free starters try Andrea-mosaic or Foto-Mosaik. These programs are versatile and impressive for making your masterpiece.
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Click here to Download Andrea-mosaic by Andrea Denzler
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1) After installing Andrea-mosaic there are many icons in the Start Menu. Begin with the icon that says only Andrea-mosaic. However, all of the icons launch the same program from what I can tell.
2) Building a collection starts by left-clicking the Find Tiles button. A different window comes up that is labeled Choose an image collection. Left-click the Create collection button and you are prompted for your Collection name and location. You are doing two things at this point. First you are titling your database or collection as we call it. More importantly, you are giving Andrea-mosaic a starting location for drilling down to find images. So assure where you save this name is the upper location where all your images are! Provide a name and pushing SAVE. Keep in mind that when I pointed it at my 8,000 family photos it took a very long time to catalogue all of them into a collection. This is the most tiring part of making a robust mosaic. At the bottom of the "chooose image collection" window you will notice the status of assembling your collection and percentage of completion..
3) Next left-click the Load Collection button and load in the file you made in the previous step. A dialog box will pop-up and inform you of how many images are in your selected collection and give you a Load Complete 100% status if all went well. Now close out of this window using the Close button at the center bottom of the window.
Note: Andrea visually appears as if you are supposed to start at the top of the main program window and fill out the applicable boxes as you go down sequentially. Unfortunately this doesn't work too well. Although we have already done the "Find Tiles" procedure it's time to jump around a bit. The numbers on top influence the numbers you fill in toward the bottom for your preferences. In other words, inputting a larger image in the "Step-3" block suddenly changes the amount of tiles you can choose back in "Step-2". So you have to jump around for best results.
4) Move down to Andrea-mosaics STEP-3 and select the Add Image button. Note when we say steps on the AndreaMosaic window there are sections squared off and the words "Step 1" for instance starting each section.
5) There is a row outlined completely by a box in the very center of the window. Notice the status of your preferences in is area. It tells you the Mosaic Size, Tile Width, Total Size, and how many tiles you are dealing with to make your image. By altering all these preferences the size of your image will change. So it is important to keep an eye on these status numbers in that center row. Change the Width of the Mosaic on the top row and watch the Mosaic Size and status numbers change with it in that center row. Change the tiles per row and check the status line again.
6) On the third line fill in a number for Width of Tiles such as 150 pixels. This assures the smaller tiles are clear for viewing and printing.
7) Begin the mosaic by left-clicking Step-4 Create the Mosaic's. The progress of assembling your mosaic is shown at the bottom of the Andrea-mosaic window. Also there is a dashed line to visually give you an idea of how long it will take. The times of creation will vary.
8) Just as a note, If you are looking for a way to stop the tiles from rotating on AndreaMosic then check out Step#2 and the 8th blank down. The pull-down menu probably says Flip-Horizontal. Changing this will constrain the flipping that is done.
The image just created should be in the same folder where you chose your master image from. It will have a similar but different name.
Andrea-Mosaic version cropped for head only.
Now for a Mosiac done via video. If you are the type person who learns faster from watching than reading the below video may be helpful to you. Here a gentleman creates the entire photo-mosaic in about 2.34 minutes. Once you see the work-flow of the program you can head straight into the process as shown in the video. Feel free to send me feedback if this tutorial worked for you or maybe why it didn't. I've just put up a feedback area in the icon at the bottom of the screen. Happy mosaicing!
Andrea-mosaic Video demo
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Click here for my tutorial on Foto-mosaik >>
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Written Sep07 and updated Oct09 by Tracy Rose