Video signal processing circuit and color adjusting circuit for color video signal
AssigneePioneer Corporation
InventorTetsuya Shigeta
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Abstract
A video signal processing circuit for making adjustments of a brightness, a contrast, a hue, and the like of a color video signal by a simple circuit construction. Input video signals which are supplied as 3-primary color signals or luminance and color difference signals are converted to the luminance and color difference signals or the 3-primary color signals and processed to effect adjustments of a picture displaying form, and the adjusted signals are inversely converted subsequently.
Claims5
A video signal processing circuit comprising:
- first matrix arithmetic operating means for performing a first matrix arithmetic operation based on a first coefficient group to 3-primary color signals R, G, and B or a luminance signal Y and two color difference signals PR and PB as input video signals and outputting the luminance signal Y and two color difference signals PR and PB or the 3-primary color signals R, G, and B;
- signal processing means for performing a signal process to an output signal of said first matrix arithmetic operating means and adjusting a picture display form;
- second matrix arithmetic operating means for performing a second matrix arithmetic operation based on a second coefficient group to signals output from the signal processing means and outputting the 3-primary color signals R, G, and B or the luminance signal Y and two color difference signals PR and PB;
- and
- coefficient adjusting means for adjusting values of said first and/or second coefficient groups.
A color adjusting circuit of a color video signal for obtaining color adjustment color difference signals by performing a color adjusting process according to a color adjustment signal to color difference signals in the color video signal, comprising:
- a first coordinates transforming circuit for performing a rotary coordinate transformation to said color difference signals in a first direction by an amount corresponding to a color designation angle according to a color designation signal, thereby obtaining rotated color difference signals;
- a region discriminating circuit for discriminating whether or not said color difference signals exist in a color region represented by said color designation signal in color coordinates;
- a level adjusting circuit for performing a level adjustment according to said color adjustment signal only to said rotated color difference signals obtained on the basis of said color difference signals which were determined to be existing in said color region;
- and
- a second coordinates transforming circuit for performing a rotary coordinate transformation to said rotated color difference signals subjected to the level adjustment by said level adjusting circuit by the amount corresponding to said color designation angle in the direction opposite to the first direction and outputting a resultant signal as said color adjustment color difference signals.
Dependencies are inferred from the claim text.