Image coding device and image decoding device

摘要

To provide an image coding device having high coding efficiency and an image decoding device. A plurality of prediction procedures that uses various types of correlations between pixels are adaptively applied with a coded signal as a reference. With respect to an input pixel, first residual and prediction information are obtained by a first prediction unit that carries out in-screen prediction and the like, second residual and prediction information are obtained by a second prediction unit for predicting a first residual as a serial additional process, and third residual and prediction information are obtained by a third prediction unit for directly predicting a pixel to be coded as a parallel additional process on the input pixel. Which of either the second residual or the third residual to code is determined based on the coding cost, and the signal is switched in the first switching unit.

主权项

1. An image coding device for coding an input image for every unit block in coding using prediction, the image coding device comprising:
a first prediction unit for determining first prediction information for predicting a block to be coded using a reconstructed pixel signal reconstructed using a coded signal; a first compensation unit for obtaining a first prediction signal of said block to be coded from said first prediction information and said reconstructed pixel signal; a first differential unit for obtaining a difference between a signal of said block to be coded and said first prediction signal as a first residual signal; a second prediction unit for determining second prediction information as a prediction coefficient for predicting said first residual signal using a reconstructed residual signal reconstructed using the coded signal; a second compensation unit for obtaining a second prediction signal of said first residual signal from said second prediction information and said reconstructed residual signal; a second differential unit for obtaining a difference between said first residual signal and said second prediction signal as a second residual signal; a third prediction unit for determining third prediction information as a prediction coefficient for predicting said block to be coded using said reconstructed pixel signal; a third compensation unit for obtaining a third prediction signal of said block to be coded from said third prediction information and said reconstructed pixel signal; a third differential unit for obtaining a difference between a signal of said block to be coded and said third prediction signal as a third residual signal; and a switching unit for switching and selecting one of either said second residual signal or said third residual signal for every unit block, wherein orthogonal transformation, quantization, and coding are performed on the selected residual, and said reconstructed residual signal and said reconstructed pixel signal are obtained using prediction information corresponding to the selected residual to code the prediction information.