Image processing system, processing method, and storage medium

1. An image processing system comprising:

a memory that stores a program; and

a processor that executes the program stored in the memory so as to function as units comprising:

a detection unit configured to detect a boundary of a retinal layer in a tomographic image of an eye to be examined;

a calculation unit configured to calculate, at respective points or the boundary of the retinal layer detected by the detection unit, each of signed curvature values corresponding to one of the points of the boundary of the retinal layer;

a generation unit configured to generate a curvature map based on the signed curvature values calculated by the calculation unit;

a display control unit configured to display on a display device the curvature map generated by the generation unit; and

a graph generation unit configured to generate a graph that has a first axis and a second axis, the first axis plotting an average value of the signed curvature values and the second axis plotting a variance value of the signed curvature values,

wherein the curvature map has a display form which is recognizable whether it is an upward or downward convex shape; and

wherein the display control unit displays, on the display device, the graph on which a mark indicating the signed curvature values is superimposed.

2. The system according to claim 1 , wherein the display form has a color whose density is changed depending on the signed curvature values,

wherein the curvature map has the display form which is recognizable whether or not the boundary of a retina shape is smooth by a difference in density of color.

3. The system according to claim 2 , wherein the display form has a dark color which expresses a point having a strong curvature and a light color which expresses a point having a moderate curvature.

4. The system according to claim 1 , wherein the display form has a first color and a second color which are selected depending on positive and negative curvature values with reference to a curvature value=0.

5. The system according to claim 1 , wherein the display control unit displays the tomographic image on which the detected boundary of the retinal layer is superimposed.

6. The system according to claim 1 , wherein the units further comprise an analysis unit configured to analyze the detected boundary of the retinal layer for generating a layer thickness map, and

wherein the display control unit displays the layer thickness map on the display device.

7. The system according to claim 6 , wherein the analysis unit analyzes the detected boundary of the retinal layer for generating a layer thickness graph, and

wherein the display control unit displays the layer thickness map and the layer thickness graph on the display device.

8. The system according to claim 1 , wherein the units further comprise a selection unit configured to select the retinal layer from retinal layers, and

wherein the display control unit displays the curvature map of the boundary of the retinal layer selected by the selection unit.

9. The system according to claim 1 , wherein the units further comprise a fundus image capturing unit configured to capture a fundus image of the eye to be examined,

wherein the display control unit displays, on the display device, the fundus image on which the curvature map is superimposed.

10. The system according to claim 1 , wherein the graph includes a first region free from symptom or posterior staphyloma and a second region suffering a symptom of posterior staphyloma.

11. The system according to claim 10 , wherein the mark is identifiable from marks corresponding to feature amounts held in a database.

12. A processing method of an image processing system, comprising:

detecting a boundary of a retinal layer in a tomographic image of an eye to be examined;

calculating, at respective points of the boundary of the retinal layer detected by a detection unit, each of signed curvature values corresponding to one of the points of the boundary of the retinal layer;

generating a curvature map based on the signed curvature values calculated in the calculating;

displaying on a display device the curvature map generating in the generating; and

generating a graph that has a first axis and a second axis, the first axis plotting an average value of the signed curvature values and the second axis plotting a variance value of the signed curvature values;

wherein the curvature map has a display form which is recognizable whether it is an upward or downward convex shape, and

wherein displaying on the display device includes displaying the graph on which a mark indicating the signed curvature values is superimposed.

13. A non-transitory computer readable storage medium storing a program for controlling a computer to execute a processing method of an image processing system, the method comprising:

detecting a boundary of a retinal layer in a tomographic image of an eye to be examined;

calculating, at respective points of the boundary of the retinal layer detected by a detection unit, each of signed curvature values corresponding to one of the points of the boundary of the retinal layer;

generating a curvature map based on the signed curvature values calculated in the calculating;

displaying on a display device the curvature map generated in the generating; and

generating a graph that has a first axis and a second axis the first axis plotting an average value of the signed curvature values and the second axis plotting a variance value of the signed curvature values,

wherein the curvature map has a display form which is recognizable whether it is an upward or downward convex shape; and

wherein displaying on the display device includes displaying the graph on which a mark indicating the signed curvature values is superimposed.