Image processing apparatus for endoscope, endoscope system and image processing method for endoscope

1. An image processing apparatus for an endoscope, wherein any one of a plurality of insertion units is detachably connectable to the image processing apparatus, the plurality of insertion units respectively having imaging devices with numbers of pixels different from one another installed therein, the image processing apparatus comprising:

an image signal processing unit that processes an image signal captured by a connected imaging device; and

an image data generation unit that generates image data,

wherein the image signal processing unit:

converts a pixel density of the image signal to a high density without changing a number of pixels;

disposes the image signal after conversion to the high density on an image data area in a normalized signal, and disposes a dummy signal on a dummy signal supplementing area in the normalized signal, so as to generate a standard image signal, wherein an amount of data of the standard image signal coincides with an amount of data of the normalized signal; and

outputs, to the image data generation unit, the standard image signal and a clock signal indicating a boundary of cut-out of the image signal after conversion to the high density, and

wherein the image data generation unit:

extracts the image signal after conversion to the high density from the standard image signal, based on the clock signal; and

generates the image data from the extracted image signal.

2. An image processing method for an endoscope, the image processing method comprising:

processing an image signal captured by an imaging device of an insertion unit connected to a main apparatus of an endoscope apparatus, wherein the insertion unit is from among a plurality of insertion units any one of which is detachably connectable to the main apparatus, the plurality of insertion units respectively having imaging devices with numbers of pixels different from one another installed therein; and

generating image data;

wherein the processing of the image signal includes:

converting a pixel density of the image signal to a high density without changing a number of pixels;

disposing the image signal after conversion to the high density on an image data area in a normalized signal, and disposing a dummy signal on a dummy signal supplementing area in the normalized signal, so as to generate a standard image signal, wherein an amount of data of the standard image signal coincides with an amount of data of the normalized signal; and

outputting the standard image signal and a clock signal indicating a boundary of cut-out of the image signal after conversion to the high density, and

wherein the generating of the image data includes:

extracting the image signal after conversion to the high density from the standard image signal, based on the clock signal; and

generating the image data from the extracted image signal.

3. The image processing apparatus according to claim 1 , wherein the image signal processing unit converts the pixel density of the image signal to the high density such that a time for processing data of one pixel of the image signal becomes equal to a time in which the image data generation unit processes data of one pixel of the normalized signal.

4. The image processing apparatus according to claim 1 , wherein the image data generation unit generates the image data based on a common constant clock frequency, and

wherein the image signal processing unit converts the pixel density of the image signal to the high density without changing the number of pixels so as to allow generation of the image data based on the common constant clock frequency.