A method for multiplying the speed-resolution product of a raster scanning or imaging device such as an inkjet printer, and a resulting pixel image data structure, are disclosed. Illustratively, a 300-dot per inch (dpi) by 600-dpi logical pixel image is mapped to a corresponding, non-overlapping physical dot image, and the printer's inkjets are fired responsive to the dot image to direct generally spherical ink droplets onto paper at 600-dpi resolution grid timing in order effectively to double the horizontal resolution of the printed pixel image, without increasing the firing rate of the print head. In order to accomplish this, and to avoid ink dot overlap, the printable pixel image is thinned before it is printed by a method that leaves no visible horizontal or vertical gaps by selectively turning off pixels within a `black` image that were on and that otherwise would result in ink dot overlap and slower print head speeds were the inkjets cycled at 600-dpi resolution timing. Pixel thinning is performed substantially without adversely affecting pixel image edge definition.