Illllllllllllllllllllllllllllllllllllllllllllllllll
US006967600B2
(12) United States Patent ao) Patent No.: us 6,967,600 B2
Kadono et al. (45) Date of Patent: Nov. 22,2005
(54) VARIABLE LENGTH CODING METHOD AND VARIABLE LENGTH DECODING METHOD
(75) Inventors: Shinya Kadono, Nishinomiya (JP);
Satoshi Kondo, Yawata (JP); Makoto
Hagai, Moriguchi (JP); Kiyofumi Abe,
Kadoma (JP)
(73) Assignee: Matsushita Electric Industrial Co.,
Ltd., Osaka (JP)
( * ) Notice: Subject to any disclaimer, the term ol this patent is extended or adjusted under 35 U.S.C. 154(b) by 45 days.
(21) Appl. No.: 10/480,038
(22) PCT Filed: Nov. 22, 2002
(86) PCT No.: PCT/JP02/12230
§ 371 (c)(1),
(2), (4) Date: Dec. 9, 2003
(87) PCT Pub. No.: WO03/045065 PCT Pub. Date: May 30, 2003
(65) Prior Publication Data
US 2004/0174278 Al Sep. 9, 2004
(30) Foreign Application Priority Data
Nov. 22, 2001 (IP) 2001-358197
Apr. 1, 2002 (IP) 2002-099227
(51) Int. CI. II03M 7/40
(52) U.S. CI 341/67; 51/58
(58) Field of Search 341/58, 51, 65,
341/67, 59, 95, 107; 382/176, 224, 233
(56) References Cited
U.S. PATENT DOCUMENTS
5,233,348 A * 8/1993 Pollmann et al 341/67
5,471,206 A * 11/1995 Allen et al 341/51
5,717,394 A * 2/1998 Schwartz et al 341/51
5,729,690 A 3/1998 leong et al.
5,825,312 A * 10/1998 D'Ortenzio 341/65
5,995,148 A 11/1999 Haskell et al.
6,011,496 A * 1/2000 Park et al 341/55
6,016,111 A * 1/2000 Park et al 341/55
6,241,778 Bl * 6/2001 de Lind van Wijngaarden
etal 341/58
6,661,355 B2 * 12/2003 Cornelius et al 341/58
6,731,814 B2 * 5/2004 Zeck et al 382/239
6,754,394 B2 * 6/2004 Boliek et al 382/240
FOREIGN PATENT DOCUMENTS
EP 0 987 899 3/2000
IP 06-021830 1/1994
IP 06-237184 8/1994
IP 06-311534 11/1994
IP 8-79088 3/1996
OTHER PUBLICATIONS
"H.26L Test Model Long Term No. 8 (TML-8)draftO", ITU-Telecommunication Standardization Sector, Jun. 28, 2001, Section 4.3 pp. 17-18, Sections 5.1 and 5.2 pp. 22-29. Miki, S., "All About MEPG^l" Kogyo Chosakai Publishing Co. Ltd., First Edition, Sep. 1998, pp. 69-73.
* cited by examiner
Primary Examiner—Lam T. Mai
(74) Attorney, Agent, or Firm—-Wenderoth, Lind & Ponack, L.L.P.
(57) ABSTRACT
An image coding apparatus provides a run-length encoding unit RLE1 that subjects quantized coefficients which are obtained by quantizing frequency components ol an image signal to a variable length coding process by using a run value Run that indicates the number ol successive zero coefficients and a level value Lev that indicates a value ol 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 ol a quantization parameter QP; a reordering unit Rreodr for reordering run values Run from high frequency component ol 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 ol already-processed run values.
1 Claim, 36 Drawing Sheets
