An image sensor apparatus comprising: an imaging section adapted to photograph an inspection target to obtain a color image to be measured; a display section; and an image processing device which comprises: an input unit, and a CPU unit which, in a color specification setting mode, is adapted to specify a specific region with respect to a model color image which is constituted by a plurality of pixels and displayed in an image display region of the display section, by setting a specific pixel selectable by a user in the image display region via the input unit and surrounding pixels having a positional relationship defined in advance with respect to the specific pixel as the specific region, acquire color information represented by at least two variables out of three independent variables defining a color for the pixels contained in the specific region, display, in a color map region of the display section, a color map which bases on the predetermined variables and, as a color map position, the color information, wherein the color information is adjustable by the user via the input unit, extraction-process pixels having the color information corresponding to the color map position set according to an instruction by the user via the input device out of the plurality of pixels configuring the model color image and to display the pixels having the color information corresponding to the color map position in the image display region of the display section, wherein a number of the displayed pixels having the color information corresponding to the color map position is displayed, and to store the color information corresponding to the color map position, wherein the stored color information is useable when executing the measurement mode; wherein the CPU unit, in a determination condition setting mode, is adapted to set a range of number of pixels inputted by the user via the input unit on a setting screen displayed by the display section, as the range to be determined as an OK-determination in the measurement mode; and the CPU unit, in the measurement mode, is adapted to acquire color information for each pixel included in a processing target region (AREA) of the image to be measured, to determine for each pixel whether the color information of the pixel satisfies the stored color information, and to calculate the number of pixels having color information satisfying the stored color information, wherein the CPU unit, in the measurement mode, is adapted to obtain the OK-determination when the number of pixels having color information satisfying the stored color information is within the set range for OK-determination. an imaging section adapted to photograph an inspection target to obtain a color image to be measured; a display section; and an image processing device which comprises: an input unit, and a CPU unit which, in a color specification setting mode, is adapted to an input unit, and a CPU unit which, in a color specification setting mode, is adapted to specify a specific region with respect to a model color image which is constituted by a plurality of pixels and displayed in an image display region of the display section, by setting a specific pixel selectable by a user in the image display region via the input unit and surrounding pixels having a positional relationship defined in advance with respect to the specific pixel as the specific region, acquire color information represented by at least two variables out of three independent variables defining a color for the pixels contained in the specific region, display, in a color map region of the display section, a color map which bases on the predetermined variables and, as a color map position, the color information, wherein the color information is adjustable by the user via the input unit, extraction-process pixels having the color information corresponding to the color map position set according to an instruction by the user via the input device out of the plurality of pixels configuring the model color image and to display the pixels having the color information corresponding to the color map position in the image display region of the display section, wherein a number of the displayed pixels having the color information corresponding to the color map position is displayed, and to store the color information corresponding to the color map position, wherein the stored color information is useable when executing the measurement mode; wherein the CPU unit, in a determination condition setting mode, is adapted to set a range of number of pixels inputted by the user via the input unit on a setting screen displayed by the display section, as the range to be determined as an OK-determination in the measurement mode; and the CPU unit, in the measurement mode, is adapted to acquire color information for each pixel included in a processing target region (AREA) of the image to be measured, to determine for each pixel whether the color information of the pixel satisfies the stored color information, and to calculate the number of pixels having color information satisfying the stored color information, wherein the CPU unit, in the measurement mode, is adapted to obtain the OK-determination when the number of pixels having color information satisfying the stored color information is within the set range for OK-determination.