A projection system comprising: a projector configured to project a content image and a pattern image satisfying a predetermined condition onto a projection surface having a front surface, the front surface being not a solid color; a camera configured to photograph the projection surface at a photographing timing, the photographing timing being a timing at which the pattern image is projected; a camera deformation value calculation unit configured to calculate a texture deformation value indicating a change in position, orientation, or shape of the projection surface on the basis of a camera image, the camera image being a photographing result of the camera; a projector deformation value acquisition unit configured to acquire a projector deformation value of image deformation for converting an image projected by the projector into an image according to a state of the projection surface on the basis of the pattern image captured in the camera image and the texture deformation value; and a transmission image acquisition unit configured to execute processing of performing image deformation on the content image on the basis of the projector deformation value and processing of performing image deformation on the pattern image on the basis of the projector deformation value; wherein the predetermined condition is a condition that a plurality of types of solid color regions having different brightness values are included; characterized in that the camera deformation value calculation unit calculates the texture deformation value on the basis of a target location of the front surface of the projection surface of the pattern image captured in the camera image, the target location being a region inside a solid color region of said plurality of types of solid color regions and being a region located at a position away from an outer circumference of the solid color region by a distance according to a speed of movement or rotation of the projection surface and an interval between timings of photographing by the camera. a projector configured to project a content image and a pattern image satisfying a predetermined condition onto a projection surface having a front surface, the front surface being not a solid color; a camera configured to photograph the projection surface at a photographing timing, the photographing timing being a timing at which the pattern image is projected; a camera deformation value calculation unit configured to calculate a texture deformation value indicating a change in position, orientation, or shape of the projection surface on the basis of a camera image, the camera image being a photographing result of the camera; a projector deformation value acquisition unit configured to acquire a projector deformation value of image deformation for converting an image projected by the projector into an image according to a state of the projection surface on the basis of the pattern image captured in the camera image and the texture deformation value; and a transmission image acquisition unit configured to execute processing of performing image deformation on the content image on the basis of the projector deformation value and processing of performing image deformation on the pattern image on the basis of the projector deformation value; wherein the predetermined condition is a condition that a plurality of types of solid color regions having different brightness values are included; characterized in that the camera deformation value calculation unit calculates the texture deformation value on the basis of a target location of the front surface of the projection surface of the pattern image captured in the camera image, the target location being a region inside a solid color region of said plurality of types of solid color regions and being a region located at a position away from an outer circumference of the solid color region by a distance according to a speed of movement or rotation of the projection surface and an interval between timings of photographing by the camera.