Endoscope system and endoscope image generation method

An endoscope system for inspecting a plurality of blades arranged periodically along a rotating direction of a rotary shaft, the endoscope system comprising:

• a first linear sensor comprising an image pickup area along a direction perpendicular to a rotating direction of the plurality of blades that are rotatable, the first linear sensor being configured to pick up images of the plurality of blades at predetermined time intervals to acquire a plurality of first blade images that are one-dimensional images containing an entirety of one of the plurality of blades;
• a second linear sensor comprising an image pickup area along the rotating direction of the plurality of blades that are rotatable, the second linear sensor being configured to pick up images of the plurality of blades at the predetermined time intervals in synchronization with acquisition timing of the first blade images to acquire a plurality of second blade images that are one-dimensional images containing a width of one of the plurality of blades;
• and
• a processor comprising hardware, the processor being configured to:
• determine time-series image information formed of the acquired second blade images arranged over time;
• photograph the plurality of second blade images while rotating the plurality of blades at a constant speed by using a turning tool, estimate position change information representing a change in a position of a pixel having a predetermined luminance value corresponding to an edge portion of one of the plurality of blades in each of the plurality of second blade images, and determine, from the estimated position change information, correspondence information that relates the position of the pixel having the predetermined luminance value in each of the second blade images to an amount of an angle of rotation of the plurality of blades;
• and
• correct the plurality of first blade images, based on the time-series image information and the correspondence information.