Variable length coding method and variable length decoding method
2 Assignments
0 Petitions
Accused Products
Abstract
An image coding apparatus provides a run-length encoding unit RLE1 that subjects quantized coefficients which are obtained by quantizing frequency components of an image signal to a variable length coding process by using a run value Run that indicates the number of successive zero coefficients and a level value Lev that indicates a value of a non-zero coefficient following the zero coefficients. The run-length encoding unit RLE1 includes a reordering unit Lreodr for reordering level values Lev; a variable length coder LVLC for coding reordered level values ROLev by using a code table that is selected according to the value of a quantization parameter QP; a reordering unit Rreodr for reordering run values Run fromhigh frequency component of the quantized coefficients to low frequency component; and a variable length coder RVLC for coding reordered run values RORun by using a code table that is selected according to the number of already-processed run values
37 Citations
31 Claims
-
1-30. -30. (canceled)
-
31. A method for decoding a coded block image, the method comprising:
-
decoding coded transform coefficients from a high frequency component toward a low frequency component, in accordance with information that represents a total number of undecoded transform coefficients, to obtain decoded transform coefficients, wherein the undecoded transform coefficients are transform coefficients which have not been decoded;
inverse scanning the decoded transform coefficients into a two-dimensional array of transform coefficients; and
inverse quantizing and inverse frequency transforming the two-dimensional array of transform coefficients to obtain a reconstructed block image.
-
Specification