graphics converter: software to convert png, jpg,jpeg or bmp to dxf files, for Linux

Fransisco:

it doesn't work that way. the fundamental data stored ean each of those file types are different and not interchangeable. DXF is so called "vector" information, and png,jpeg and bmp files are "raster" information.

https://secure.wikimedia.org/wikipedia/en/wiki/Vector_graphics
https://secure.wikimedia.org/wikipedia/en/wiki/Raster_graphics

Inkscape contains a tool called "potrace" which will get you partway there, but you will need to manually edit it to get good results, as potrace will assume a smooth solution underlies the raster data (ie it will be more curvy and less "snappy" than you expect. you need to impose your own opinon of what should be snappy on top of that).

http://wiki.inkscape.org/wiki/index.php/Potrace

Depending upon the complexity of the images, DXF may be a poor choice of data storage anyway. This will only be useful for simple curves (eg splines), and other simple line art.

This manual process is what keeps Graphic designers in business.

Thank's

Thanks to both of you. I'm now using Inkscape and very happy.