To provide an image coding apparatus in which image quality deterioration is reduced by suppressing a variation in the code amount of intra-macroblocks per frame.
An image coding apparatus 1 calculates the activity of each macroblock. All the macroblocks of block lines BL1, BL3 are set to intra-candidate macroblocks (intra-candidate MBs) being candidates of intra-coding. In block lines BL2, BL4, intra-candidate MBs are set every other block. Among the intra-candidate MBs of the respective block lines, a macroblock of minimum activity is determined as an intra-macroblock of a frame F1. The macroblock determined as the intra-MB is changed from the intra-candidate MB to an intra-prohibition macroblock. After the setting state of the intra-candidate MB is changed, the intra-macroblock of a frame to be inputted next to the frame F1 is determined.
HASEGAWA HIROSHI
| JP2008516561A | 2008-05-15 | |||
| JPH0698295A | 1994-04-08 | |||
| JP2000201354A | 2000-07-18 |
Takao Matsuyama
Go Sakane
Kawakami Keiko
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