overimpose graphics on an imported image

*To*: mathgroup at smc.vnet.net*Subject*: [mg106104] overimpose graphics on an imported image*From*: "alexxx.magni at gmail.com" <alexxx.magni at gmail.com>*Date*: Fri, 1 Jan 2010 05:37:31 -0500 (EST)

hi people, I wonder if it is just me being dumb, but I'm unable to perform what I thought was a very simple operation: having imported an image of (Lx,Ly) pixels, draw above it an empty rectangle at coordinates (x0,y0) (x1,y1) (say, lower left and upper right corners). Say for example that I want to overimpose on image i1 a rectangle covering a 10% portion, if I use this: ImageCompose[i1, Graphics[Rectangle[{0, 0}, {0.1*Lx, 0.1*Ly}]]] I have (apart from a filled rectangle instead of empty, but I can deal with it later) a huge rectangle covering all of it! How these coordinates interact? Thanks for any help... Alessandro Magni

**Follow-Ups**:**Re: overimpose graphics on an imported image***From:*Patrick Scheibe <pscheibe@trm.uni-leipzig.de>