A system and method for calculating the toner usage of a multifunction
peripheral device using software and the compressed form of the raster
image without uncompressing the image. The method enables the calculation
of toner usage based on the statistics of actual colorant consumption
while minimizing the approximation error. The compressed image data
includes encoded data representing an image mapped onto a first color
space. The received compressed image is analyzed to generate a pixel
count of each color associated with the image corresponding to a color in
the first color space. In the event of a different device color space,
the pixel count is translated to a second color space, and an aggregate
pixel count is calculated. When statistical data from actual operations
is available, table data on the earlier usage is compared with the pixel
count calculated, resulting in an approximate toner usage having low
approximation error. When no previous statistical data is available, the
method uses the manufacturer stored toner usage and compares the pixel
count thereon. A device table is then generated, storing an adjusted
table containing actual usage statistics for further calculations
regarding subsequent usages.