Patent Document ID: 8743956
Application ID: 10598154
Patent Status: 1

Claim One:
1. An image encoding method comprising: generating a transformation coefficient for each block by transforming an image from a spatial domain into a frequency domain for each block, characterized by comprising the step of quantizing the plurality of transformation coefficients for each block upon setting the same quantization width in the plurality of blocks, wherein the step of quantizing comprises the steps of analyzing visual sensitivities of the plurality of blocks, determining the quantization width in accordance with a block exhibiting high visual sensitivity, setting a dead zone width larger than a dead zone width of the block exhibiting high visual sensitivity to a block with lower visual sensitivity, and quantizing the transformation coefficient; and calculating the dead zone width from at least one of a prediction mode of the image, a direction of intra frame prediction of the image, motion of the image, a direction of inter frame prediction of the image, an average absolute error of the image, a variance of the image, an image range of the image, an average absolute error of a prediction error signal of the image, and a variance of a prediction error signal of the image.