Video signal encoding and recording apparatus with variable transmission rate

• US 7,313,318 B2
• Filed: 07/01/2003
• Issued: 12/25/2007
• Est. Priority Date: 06/17/1998
• Status: Expired due to Term

• Current Assignee: JVC Kenwood Corporation
• Original Assignee: Victor Company of Japan Limited (JVC Kenwood Corporation)
• Inventors: Ueda, Motoharu, Sugiyama, Kenji
• Primary Examiner(s): Boccio, Vincent F.
• Application Number:
  US10/609,661
• Publication Number:
  US 20040022316A1
• Time in Patent Office: 1,638 Days
• Field of Search: 386/109, 386/110, 386/111, 386/112, 386125-126, 375/240.02, 378/240.03
• US Class Current: 386/295
• CPC Class Codes: G06T 9/005 Statistical coding, e.g. Huffman, run length coding
• CPC Class Codes: H04N 19/115 Selection of the code volume for a coding unit prior to coding
• CPC Class Codes: H04N 19/124 Quantisation
• CPC Class Codes: H04N 19/152 by measuring the fullness of the transmission buffer
• CPC Class Codes: H04N 19/156 Availability of hardware or computational resources, e.g. encoding based on power-saving criteria
• CPC Class Codes: H04N 19/172 the region being a picture, frame or field
• CPC Class Codes: H04N 19/177 the unit being a group of pictures [GOP]
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 5/781 on disks or drums
• CPC Class Codes: H04N 5/85 on discs or drums
• CPC Class Codes: H04N 5/907 using static stores, e.g. storage tubes or semiconductor memories H04N5/91 takes precedence
• CPC Class Codes: H04N 9/8042 involving data reduction

Abstract

In a video signal encoding and recording apparatus, a video signal is quantized into a quantization-resultant signal in response to a variable quantization scale. The quantization-resultant signal is recorded on a recording medium. The quantization scale is controlled in response to an encoding rate. The quantization scale is limited to within a range determined by a limit quantization scale. A remaining record capacity of the recording medium is measured. A remaining record time is measured. The encoding rate and the limit quantization scale are updated in response to the measured remaining record capacity and the measured remaining record time.

Claims

1. A video signal encoding and recording apparatus comprising:

first means for quantizing a video signal into a quantization-resultant signal in response to a variable quantization step;

second means for recording the quantization-resultant signal generated by the first means on a recording medium;

third means for calculating a remaining record capacity of the recording medium;

fourth means for determining a capacity of a virtual buffer in response to the remaining record capacity calculated by the third means;

fifth means for calculating a degree of occupancy of the virtual buffer having the capacity determined by the fourth means; and

sixth means for controlling the quantization step used by the first means in response to the virtual-buffer occupancy degree calculated by the fifth means;

wherein the fifth means comprises means for determining a target mean transmission rate in response to the remaining record capacity calculated by the third means, means for detecting a transmission rate of the quantization-resultant signal, and means for calculating the virtual-buffer occupancy degree in response to the target mean transmission rate, the detected transmission rate, and the virtual-buffer capacity determined by the fourth means.

2. A method of encoding and recording a video signal, comprising the steps of:

quantizing a video signal into a quantization-resultant signal in response to a variable quantization step;

recording the quantization-resultant signal on a recording medium;

calculating a remaining record capacity of the recording medium;

determining a capacity of a virtual buffer in response to the calculated remaining record capacity;

calculating a degree of occupancy of the virtual buffer having the determined capacity; and

controlling the quantization step in response to the calculated virtual-buffer occupancy degree;

wherein the virtual-buffer occupancy degree calculating step comprises determining a target mean transmission rate in response to the calculated remaining record capacity, detecting a transmission rate of the quantization-resultant signal, and calculating the virtual-buffer occupancy degree in response to the target mean transmission rate, the detected transmission rate, and the determined virtual-buffer capacity.