Abstract: Red color saturation is increased and red color with higher purity can be reproduced by composing: a red color detection circuit 1 for detecting a red color signal having higher purity by inputting color differential signals (R-Y) and (B-Y) modulated by color subcarrier, subtracting the absolute value of the (B-Y) signal from the positive polarity component of the (R-Y) signal and removing the negative part of the subtracted signal; Y signal compensation block including: first gain controller 50b for controlling the output signal amplitude of red color detection circuit 1 and a subtracter 50a for subtracting the output signal of first gain controller 50b from a luminance signal Y; an (R-Y) signal compensation block including: second gain controller 51b for controlling the output signal amplitude of red color detection circuit 1 and an adder 51a for adding the output signal of second gain controller 51b and the input (R-Y) signal; and a (B-Y) signal compensation block including: third gain controller 52b for c

Abstract: In automatic auction method which makes it unnecessary for bidders to stay before auction terminals at the time of auction and which makes possible auction transactions on an open network on which it is difficult to assure the on-line and real time properties, a plurality of auction ordering information pieces each containing a desired price, number of purchase, and a highest possible price in competition for the desired price and received from bidder terminals via on-line circuits are collected. Until an auction issue appears, the price is lowered. If there is at least one auction issue and a desired quantity which is the sum total of the numbers of purchase of the auction issues is not satisfied, then it is determined whether there is an auction issue coinciding in price by comparing the set price with (the desired price+the highest possible price in competition). Until the desired quantity is satisfied, the price is raised.

Abstract: A histogram operating unit comprises: histogram generator which receives input video signals, and creates a histogram of input video signals, a first limiter for receiving a histogram generated by the histogram generator and an externally set first limit level, and restricting the frequency of the histogram created by the histogram generator to within a specified level, and outputting a restricted histogram, a first totaling circuit for calculating the number of samples of video signals produced by the first limiter, second totaling circuit for calculating the number of samples of the input video signals, a first subtractor for subtracting the output of the first totaling circuit from the output of the second totaling circuit, and a corrected histogram generator which receives the output of the first limiter and the output of the first subtractor, and creates the corrected histogram.

Abstract: A black level detecting circuit compares an input video signal with a current minimum value of input video signals, then detects a difference between the input signal and the current minimum value when the input value is smaller than the current minimum value, and then outputs the detected difference only during a detecting period of the black level, then corrects the minimum value by using this output for renewing the current minimum value, and finally outputs this renewed minimum value as a new minimum value of the input video signal. The black level detecting circuit also latches the minimum value during the vertical blanking pulse and initializes the minimum value during a vertical blanking period so as to detect a black level of the input signal.

Abstract: A skin-color-area detector generates a skin-color-area signal from an input video signal. An average luminance level detector generates an average luminance level signal from a luminance signal. These signals are transmitted to a skin-color-corrector to generate skin-color-correction signals. At a saturation controller and at a luminance signal corrector which each receive the skin color corrections signals, skin-color is optimumly corrected. Thereby reproduction quality of skin-color signals in video signals is enhanced.

Abstract: An automatically adjustable black stretch control apparatus for a continually adjusting the black stretch of a luminance signal which comprises a black stretch control means for controlling the amount of stretch of the black part of the luminance signal. A luminance signal is input to a plurality of detecting means, each of which detects the percentage of the luminance signal that is within a specified range during a unit period (i.e. a frame). The output of each detecting means is input to one of a plurality of preprocessing means which generates a control index. The output of each preprocessing means is input to one of a plurality of inferring means for creating a synthesized function indicative of the quality of the signal from each of the detecting means.