Patent ID: 8705880

Claim:
An image compression device which compresses image data, comprising: a first quantization unit configured to perform a quantization mode 1 to quantize a plurality of pixel values included in the image data using two values A 1 and B 1 where A 1 <B 1 , in one range defined by the A 1 and the B 1 ; a second quantization unit configured to perform a quantization mode 2 to quantize the pixel values using two values A 2 and B 2 where A 2 >B 2 , in two ranges defined by the A 2 and the B 2 ; and a compressed data generation unit configured to generate compressed data including a value A, a value B, and quantized values of the pixel values quantized in a selected quantization mode, wherein the compressed data generation unit is configured to generate the compressed data using: the A 1 as the A when the quantization mode 1 is selected; the A 2 as the A when the quantization mode 2 is selected; the B 1 as the B when the quantization mode 1 is selected; and the B 2 as the B when the quantization mode 2 is selected.