Patent ID: 7050645

Claim:
An image processing apparatus, comprising: an orthogonal transformer configured to transform multi-bit image data into orthogonal transform coefficients; a quantizer configured to quantize the orthogonal transform coefficients for each spatial frequency of the multi-bit image data, the spatial frequencies including a DC component, low frequency AC components, and high frequency AC components, a first number of quantization bits being assigned to the DC component, a second number of quantization bits being assigned to all the low frequency AC components, a third number of quantization bits being assigned to all the high frequency AC components, the second number of quantization bits comprising a multiple of the first number of quantization bits, and the third number of quantization bits comprising a multiple of the first number of quantization bits, the third number of quantization bits being different than the first number of quantization bits; a block data generator configured to generate a block of data, the block of data being composed of the quantized data of each spatial frequency; a frequency bander configured to rearrange the quantized data in the generated block of data so as to band the quantized data of each spatial frequency and so as to align the quantized data of a spatial frequency of the generated block of data with the quantized data of the same spatial frequency of the next generated block of data, and to output, as bit serial data, the quantized data of the spatial frequency over a plurality of the rearranged blocks; and a coder configured to compress the bit serial data, using a coding system for facsimile communication.