Patent ID: 6990243
Filing Date: 2006-01-24
Classification: H04N

Abstract:
1. An electronic camera comprising: an image-capturing element that captures an image of a subject and outputs image data of the captured subject image; a compression processing unit that compresses the image data by converting the image data to a spatial frequency DC component and a spatial frequency AC component and by quantizing and coding the two components, wherein: said compression processing unit includes: a quantization ratio determining processing unit that determines a ratio of a DC component quantization step and an AC component quantization step (DC/AC quantization ratio) in correspondence to a target compression rate; a quantization adjustment processing unit that makes an adjustment on said DC component quantization step and said AC component quantization step while sustaining the DC/AC quantization ratio at a substantially constant value; and a compression rate control processing unit that controls said quantization adjustment processing unit so that a compression code volume resulting from the compression can be within a range according to a target compression rate.