Transmission bit-rate controlling apparatus for high efficiency coding of ...

United States Patent m

Chung et al.

[ii]

[45]

ii ni l

US005598213A Patent Number: Date of Patent:

II

5,598,213 Jan. 28, 1997

[54] TRANSMISSION BIT-RATE CONTROLLING APPARATUS FOR HIGH EFFICIENCY CODING OF MOVING PICTURE SIGNAL

[75] Inventors: Tae-yun Chung; Gyu-hwan Jung, both of Kyungki-do, Rep. of Korea

[73] Assignee: Samsung Electronics Co., Ltd.,

Kyungki-do, Rep. of Korea

[21] Appl. No.: 404,064

[22] Filed: Mar. 14,1995

[30] Foreign Application Priority Data

Mar. 15, 1994 [KR] Rep. of Korea 94-5105

[51] Int. CI.6 H04N 7/36

[52] U.S. CI 348/405; 348/419

[58] Field of Search 348/405, 419,

348/409, 415, 401, 420; 382/236, 238,

239, 251

[56] References Cited

U.S. PATENT DOCUMENTS

5,396,567 3/1995 Jass 348/405

5,404,174 3/1995 Sugahara 348/415

5,526,052 6/1996 Ar 348/405

Primary Examiner—Amelia Au

Attorney, Agent, or Firm—Leydig, Voit & Mayer

[57] ABSTRACT

In an encoder having a data formatter, a DCT circuit, a transmission rate controlling apparatus, a quantizer, a variable-length coder and an encoder buffer, for compressing a moving picture signal, the transmission rate controlling apparatus includes a segment complexity estimator for receiving outputs of the quantizer and variable-length coder and estimating the complexity of a segment of a current frame relative to a previous frame, a rate control adjustment coefficient calculator for receiving the output of the segment complexity estimator and calculating a rate control adjustment coefficient, a reference quantization coefficient calculator for receiving the rate control adjustment coefficient and the output of the encoder buffer and calculating a reference quantization coefficient, and an activity calculator for receiving the output of the data formatter, calculating activity by a macroblock unit, performing an operation on the calculated activity using the output of the reference quantization coefficient calculator and outputting a quantization coefficient.

5 Claims, 4 Drawing Sheets