Patent ID: 8483494
Filing Date: 2013-07-09
Classification: H04N

Abstract:
1. An image encoding device comprising: a first encoding unit configured to calculate a generated code amount by performing encoding of image data in increments of GOP (Group of Picture) including a reference picture and a non-reference picture in a predetermined order using predetermined quantization information; a code amount control unit configured to perform setting of quantization information for realizing a target generated code amount based on the generated code amount calculated at said first encoding unit; a quantization information distinguishing unit configured to perform calculation of a DCT (Discrete Cosine Transform) coefficient with the image of each frame of said image data as an I picture (intra encoded image) that is a reference picture, and to distinguish quantization information that minimizes the summation in increments of pictures of remainders at the time of performing division of said DCT coefficient using the quantization information in a range with the quantization information determined by said code amount control unit as a reference, as quantization information used at the time of performing last encoding; a picture-type setting unit configured to perform the setting of a picture type as to said image data in increments of said GOP, and in the case of this set picture type is different from a picture type of a picture of which the quantization information has been distinguished at said quantization information distinguishing unit, to match the picture type by setting a length of a subsequent GOP by eliminating non-reference pictures prior to the I picture and subsequent to the picture of which the quantization information has been distinguished; a second encoding unit configured to perform encoding of said image data based on the picture type set at said picture-type setting unit using said quantization information set at said code amount control unit, said quantization information including a quantizing matrix which is selected from a plurality of quantizing matrices based on distinction results of high-frequency components using the generated code amount calculated at the first encoding unit, and a generated code amount calculated at a third encoding unit, wherein the third encoding unit calculates the generated code amount by performing encoding for each of said quantization information with the image of each frame of said image data as an I picture using a plurality of different quantization information.