Using the Bitmap Tracer

I'm trying to get to grips with the bitmap tracer.

My first problem is- what's the best way to posterise an image to give it large blocks of colour rather than 8 colours spread in speckles over the whole image? Can this be done in Xara or do I need to use, say, Photoshop?

Secondly, when I trace a bitmap even without anti-aliasing on the screen or in the bitmap, I always get tiny curved shapes around it. This happens whatever settings I use. Am I doing something wrong, or is this a feature of the trace?

Jessica[img]null[/img]

I'm trying to get to grips with the bitmap tracer.

My first problem is- what's the best way to posterise an image to give it large blocks of colour rather than 8 colours spread in speckles over the whole image? Can this be done in Xara or do I need to use, say, Photoshop?

Secondly, when I trace a bitmap even without anti-aliasing on the screen or in the bitmap, I always get tiny curved shapes around it. This happens whatever settings I use. Am I doing something wrong, or is this a feature of the trace?

Jessica[img]null[/img]

Looks like the conversion to a bitmap has a lot of in between colors between the line and background. The trace finds all these pixels and gives lots of objects. I ususlly edit the trace and delete them. Maybe a black and white image would eliminate all those transition colors. I think the trace sees all the overlaping colors and lines as separate colors. So, your getting additional shapes from those areas. You could use Photoshop to use the percentage mask to select areas and set them to well defined colors. You can use any color so that the trace can define it easily. Same with the dark line since there are so many colors of it. You can mask shapes and paste them into a new image. PS knows what is on the clipboard and will make the new image size accordingly. the trace the individual shape. I think you will still get the edge shapes because of the different pixel colors between the shape and background. You might try some threshold adjustments to eliminate some of those intermediate pixels. I think I would try tracing a B&W only image and coloring later. Rich

The trace tool is a very hit and miss affair. To avoid some of the thousands of odd shapes that you mention I would recommend the following.

1: In your original drawing, if you want to have transparencies, give the shape a fill colour but no line colour. Clone it and give this shape no fill colour, black line colour and no transparency. This ensures that the black lines remain black and not shades of grey.

2: Make the shapes as big as you can prior to making a bitmap copy.

3: Make the bitmap copy 256 colour and set the maximum colour value to as low an amount as you can get away with, say 26.

4: When tracing set the mode to Limited Colour not Photographic. Then test the other settings.

I attach a screen grab of a trace using this method.

Egg

Thank you Rich and Egg. I've tried several of your suggestions and I can cut back the number of edge lines but not get rid of them completely. I thought it was just me before [img]/infopop/emoticons/icon_biggrin.gif[/img]

In any case they sometimes add texture and I like that

Jess

I was making an object for a clip view, and separated the edge objects to show the effect.