| 摘要 |
A colour gamut detecting circuit capable of detecting a particular colour gamut with precision by a simple constitution and an image sensing apparatus using this circuit. A reference colour (x0 + 1) and a detection threshold value (xth) or a reference colour (y0 + 1) and a detection threshold value (yth) are selected by selectors 44 and 45 in a time division manner to be multiplied by multipliers 47 and 48 with a luminance signal WU coming from a W matrix section 41. An image sensing signal DRC or DSC selected by a selector 55 is subtracted from the result of the multiplier 47 to calculate the absolute value of the subtraction result in an absolute value calculating section 61. The absolute value coming from the absolute value calculating section 61 is compared with the multiplication result of the multiplier 48 in a comparator 65. The time-divided comparison result obtained in the comparator 65 is adjusted in timing by a register 67 to be ANDed in an AND gate 68. Based on an output signal of the gate 68, a detect signal CT is generated for determining whether input signals are in a particular colour gamut. <IMAGE> |
