Video signal recording apparatus

• US 5,970,203 A
• Filed: 05/29/1998
• Issued: 10/19/1999
• Est. Priority Date: 08/07/1995
• Status: Expired due to Term

• Current Assignee: JVC Kenwood Corporation
• Original Assignee: Victor Company of Japan Limited (JVC Kenwood Corporation)
• Inventors: Hirasawa, Masahiro, Murayama, Takeo, Nishimoto, Naomichi, Suzuki, Tomoaki
• Primary Examiner(s): Garber, Wendy
• Assistant Examiner(s): Boccio, Vincent F.
• Application Number:
  US09/086,349
• Time in Patent Office: 508 Days
• Field of Search: 386/35, 386/33, 386/25, 386/46, 386/109, 386/112, 348/152, 348/154, 348/155, 348/419, 348/405, 348/700
• US Class Current: 386/314
• CPC Class Codes: H04N 19/126 Details of normalisation or weighting functions, e.g. normalisation matrices or variable uniform quantisers
• CPC Class Codes: H04N 19/146 Data rate or code amount at the encoder output
• CPC Class Codes: H04N 19/149 by estimating the code amount by means of a model, e.g. mathematical model or statistical model
• CPC Class Codes: H04N 19/15 by monitoring actual compressed data size at the memory before deciding storage at the transmission buffer
• CPC Class Codes: H04N 19/152 by measuring the fullness of the transmission buffer
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/18 the unit being a set of transform coefficients
• CPC Class Codes: H04N 19/192 the adaptation method, adaptation tool or adaptation type being iterative or recursive
• CPC Class Codes: H04N 19/197 including determination of the initial value of an encoding parameter H04N19/56 takes precedence
• CPC Class Codes: H04N 19/42 characterised by implementation details or hardware specially adapted for video compression or decompression, e.g. dedicated software implementation H04N19/635 takes precedence
• CPC Class Codes: H04N 19/60 using transform coding
• CPC Class Codes: H04N 9/8047 using transform coding
• CPC Class Codes: H04N 9/8227 the additional signal being at least another television signal

Abstract

In a video signal recording apparatus, a first video signal is compressed into a second video signal in response to a controllable quantization factor which determines a degree of the compression. The quantization factor is controlled to maintain a data rate of the second video signal at substantially a constant rate. A detection is made as to a magnitude of the quantization factor. A decision is made as to whether or not the detected magnitude is greater than a predetermined reference magnitude. The second video signal is recorded on a recording medium when the detected magnitude is greater than the predetermined reference magnitude.

Claims

1. A video signal recording apparatus comprising:

first means for compressing a first video signal into a second video signal in response to a fixed quantization factor which determines a degree of compression;

second means for detecting a rate of a time-domain variation in a data rate of the second video signal;

third means for deciding whether or not the detected rate of the time-domain variation is greater than a reference rate;

a recording medium; and

fourth means for recording the second video signal on the recoding medium when the third means decides that the detected rate of the time-domain variation is greater than the reference rate;

wherein the second means and the third means comprise means for detecting first values of the data rate which occur at respective moments spaced by first equal intervals, means for calculating a first average among the first values, means for detecting second values of the data rate which occur at respective moments spaced by second equal intervals longer than the first equal intervals, means for calculating a second average among the second values, and means for deciding whether or not the detected rate of the time-domain variation is greater than the reference rate in response to a relation between the first average value and the second average value.