The Parameters of AndreaMosaic

In this Chapter you can learn more about the advanced parameters of the program.

I. Width of the Mosaic

This value is the total width in pixels of the final mosaic. Higher values will create mosaics with a higher resolution. This is necessary only if you want to print the image. I suggest this table for a reference:

Use of the mosaic	Width of the Mosaic
Wallpaper use	2000 pixel
High Quality Print of about 15” / 40cm	4000 pixel
High Quality Print of about 30” / 80cm	8000 pixel

You can also specify the Width of every single tile instead of the total width. In that case the Total Width will be calculated automatically.

II. Number of tiles per row

With this parameter you choose how many tiles should the final mosaic have. I like mosaics with few tiles (between 200 and 600), but you need a really high number of Images in your Image Collection (several thousands) in order to find the right one and to build good mosaics. For good results I suggest a high number of tiles, for example 1000 tiles, 2000 tiles or even more. But it depend on the use you will make of the mosaic. If you choose to print the photographic mosaic, take care that every tile is big enough to be well visible, at least a width of 0.5 inch (1.3 cm).

The best is to make different mosaics and to print a little piece of it. At last you will choose the best one.

III. Minimum Distance between duplicated tiles

The parameter “minimum distance between duplicated tiles” is important to understand. A value of 3 for example means that you permit the program to use a tile more than once but they have to be at a distance of at least 3 tiles each other, so there need to be at least 2 tiles between every duplicated tile. This parameter is very important especially if you have only few images in your Image Collection (less than 1000).

Low values will create mosaics more close to the original image, but they will have a side effect of using too many times the same tile. Here is an example.

High values will create more rich mosaics, with many different tiles. Be careful, if you choose a too high number then there will be some black holes in the mosaic because the program is unable to find any tile without duplicating them.

Usually I set this number as high as possibile, based on the number of images in my Image Colelction. I recommend this table:

Number of Images in the Image Collection	Minimum Distance between duplicated tiles
Less than 50	1
Between 50 and 200	1 or 2
Between 200 and 1000	4
Between 2000 and 5000	8
Over 5000 images	15

IV. How much can I modify every tile?

To archive a better result the program will change every tile a little. You can choose with this parameter how much. A value of 0 means that the tiles will not modified at all. I suggest at least a value of 5%. But usually I use to change 10%-15%. I do not suggest higher values because else there will be a transparent effect with the original image. Try for example a value of 50%.

V. What algoritm should I use?

Here you choose how the mosaic will be created:

Algoritm	Description
Exponential	This is the old algoritm. I do not use it anymore.
Standard	This is the actual algoritm. It is similar to the Exponential but less strong. It archive better results than the exponential.
Flip Horizontally	This is the standard algoritm. But The program also Flip every tile to see if it have a better match. With this technique you virtually double the number of Images in your collection.
Flip Horizontally + Vertically	This is like the Flip Horizontally. But I also try to flip the image vertically to find out a better match. This virtually double again the number of images in your collection. The side effect is that sometimes you will see some tiles upside-down.

VI. Is the Image Collection Extracted from a movie?

Usually this parameter can be 0. But if your image collection is an extraction of a movie file, then probably there are many similar images, called frames, and they are near each other (they have similar names, like FRAME01.JPG, FRAME02.JPG, FRAME03.JPG, etc).

So even if you set use a good value for the parameter “Distance between duplicated tiles”, it can happen that the program will use many similar images for an area of the mosaic. Only if this happen, then I suggest to use a value for the minimum distance between frames. In other words if you set a value of 5, then this means that two tiles can be near each other only if there exist at least 4 images between two two tiles, inside the sequence of the frames. I suggest to increase slowly this value only if needed for a particular Image Collection.

IMPORTANT NOTE: The sequence parameter will be used only for directories (or files) that contain the name “FRAMES”. So it is possible to have in one Image Collection Frames that use the Sequence Algorithm and standard images that use the normal Distance Algorithm.

VII. Do you want a black line around every tile?

Normally this value is 0. But I noticed that a value of 1 or 2 can be interesting if the mosaic is printed. In that case it will add a black line between every tile.