Image forming apparatus which effects output gray level correction

Claim 1

An image forming apparatus comprising: first storing means for storing input gray level-output gray level characteristic data which represent an output gray level relative to an input gray level; a density processing section which receives input gray level-output gray level characteristic data from said first storing means, said density processing section including a second storing means for storing input gray level-output gray level characteristic data transferred to said density processing section from said first storing means, and address generating means for generating addresses corresponding to said second storing means in response to input gray level data, said second storing means and said address generating means cooperating to supply output gray level data from an address in said second storing means when said address is specified by said address generating means; inputting means for inputting characteristic correcting data, said characteristic correcting data providing input gray level-output gray level corrections corresponding to a plurality of division steps which divide input gray levels; correcting means for correcting input gray level-output gray level characteristic data stored in said first storing means on the basis of characteristic correcting data supplied by said inputting means; and reversal phenomenon correcting means for making an input gray level-output gray level characteristic data correction where an output gray level of a first input gray level step having relatively low input gray levels is higher than an output gray level of a second input gray level step having relatively high input gray levels, so that said output gray level of said first input gray level step is no higher than said output gray level of said second input gray level step.