PROJECTION SYSTEM, IMAGE PROCESSING APPARATUS, AND CORRECTION METHOD

• US 20150213584A1
• Filed: 01/08/2015
• Published: 07/30/2015
• Est. Priority Date: 01/24/2014
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: ISHIKAWA, Masaaki, UCHIYAMA, Yukinaka
• Granted Patent: US 9,818,377 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 3/1446 display composed of modules, e.g. video walls
• CPC Class Codes: G09G 2320/0285 using tables for spatial correction of display data
• CPC Class Codes: G09G 2320/08 Arrangements within a display terminal for setting, manually or automatically, display parameters of the display terminal
• CPC Class Codes: G09G 2340/12 Overlay of images, i.e. displayed pixel being the result of switching between the corresponding input pixels
• CPC Class Codes: G09G 5/377 for mixing or overlaying two or more graphic patterns G09G5/02, G09G5/397 take precedence
• CPC Class Codes: H04N 9/3147 Multi-projection systems displays in general H04N9/12; video walls G06F3/1446, G09G2300/026
• CPC Class Codes: H04N 9/3185 Geometric adjustment, e.g. keystone or convergence optical or mechanical adjustment of convergence H04N9/317; using scanning means H04N3/22; optical or mechanical adjustments of projectors not peculiar to the presence of an electronic spatial light modulator G03B21/14
• CPC Class Codes: H04N 9/3194 including sensor feedback

Abstract

A projection system includes projection units collectively projecting an image as a whole on a projection area; a generation unit generating corrected images including correction points which are used for detecting distortions of projection images based on designated relationships; and a compensation coefficient calculation unit calculating compensation coefficients, based on correction captured images acquired from the corrected images on the projection area. Further, margin parts are generated in the corrected images in a manner so that parts defining the correction points in the corrected images are projected within the projection area while the parts defining correction points in the corrected images corresponding to the projection units that are next to each other are overlapped.

Claims

1. A projection system comprising:

a plurality of projection units configured to collectively project an image as a whole on a projection area;

a generation unit configured to generate corrected images including respective correction points which are used for detecting distortions of projection images, which are projected by the respective projection units, based on designated relationships between the projection images of the projection units and the projection area; and

a compensation coefficient calculation unit configured to calculate compensation coefficients, which correspond to the projection units, based on one or more correction captured images that are acquired by capturing the corrected images projected on the projection area,

wherein the generation unit is configured to further generate margin parts in the corrected images, which correspond to the projection units that project the projection images in outer areas of the projection area, in a manner so that parts defining the correction points in the corrected images are projected within the projection area while the parts defining correction points in the corrected images corresponding to the projection units that are next to each other are overlapped.

2. The projection system according to claim 1,

wherein the generation unit is configured to further generate positioning markers in peripheral areas of the parts defining the correction points in the corrected images of the projection units that project the projection images in corner areas of the projection area, the positioning markers defining reference points that are used as marks in positioning to the corner areas of the projection area.

3. The projection system according to claim 2,

wherein the generation unit is configured to define a projection target area, to which the image as a whole is collectively projected by the projection units, based on plural reference points which correspond to all corners of the projection area, the reference points being extracted from the one or more correction captured images, and

wherein the compensation coefficient calculation unit is configured to calculate the compensation coefficients, which correspond to the projection units, based on the reference points.

4. The projection system according to claim 3, further comprising:

a moving instruction receiving unit configured to receive moving instructions to move the reference points defining the projection target area while the image as a whole is projected on the projection target area,

wherein the compensation coefficient calculation unit is configured to recalculate the compensation coefficients, which correspond to the projection units, based on the reference points that have been updated in response to the moving instructions.

5. The projection system according to claim 4,

wherein the moving instruction receiving unit includes a user interface that is provided to change adjustment amounts, with a granularity of plural steps, relative to initial positions of four-corner reference points defining the projection target area, and

wherein the adjustment amounts refer to values on an integrated coordinate system where the correction points of the projection units are integrated, and are scaled by using coordinates of the reference points in the integrated coordinate system and coordinates of the positioning markers on coordinate systems of the projection units.

6. The projection system according to claim 1,

wherein the designated relationships between the projection images of the projection units and the projection area include installation conditions of the projection units and shape characteristics of the projection area, and

wherein the installation conditions of the projection units include a number of installed projection units, an arrangement manner of the projection images of the projection units, and an aspect ratio of the projection images of the projection units, and the shape characteristics of the projection area include an aspect ratio of the projection area.

7. The projection system according to claim 1,

wherein the designated relationships between the projection images of the projection units and the projection area include relative positional information of the projection area relative to the projection images projected from the projection units.

8. The projection system according to claim 7, further comprising:

an output unit configured to output initial corrected images, which include area designation markers which are to be positioned at a periphery of the projection area, to the projection units that project the images in peripheral areas of the projection area; and

a receiving unit configured to receive moving instructions to move the area designation markers,

wherein the relative positional information of the projection area is acquired in response to the moving instructions to move the area designation markers.

9. The projection system according to claim 1, further comprising:

projection image output units configured to simultaneously output images in which figure patterns defining lattice points are written on a background having brightness greater than or equal to a predetermined value to the respective projection units in the case of initial installations of the projection units.

10. The projection system according to claim 1,

wherein the compensation coefficient calculation unit includes

a correction point extraction integration processing unit that extracts the correction points from the correction captured images, and calculate coordinates of the correction points on the integrated coordinate system that is integrated by performing a projective transformation between coordinate systems of the correction captured images.

11. The projection system according to claim 3,

wherein the compensation coefficient calculation unit includes

a projective transformation acquisition unit configured to acquire projective transformation from the projection target area to the image as a whole based on coordinates of the reference points defining the projection target area and coordinates of corners if the image as a whole,

a conversion unit configured to convert the coordinates of the correction points of the projection units into the coordinate system of the image as a whole based on the projective transformation, the correction points being extracted from the correction captured images, and

a geometric compensation coefficient calculation unit configured to calculate geometric compensation coefficients that provide the projection images projected by the projection units by associating coordinate systems of the projection units with a coordinate system of the image as a whole based on the relationships between the correction points on the coordinates of the projection units and the extracted correction points.

12. The projection system according to claim 11,

wherein the compensation coefficient calculation unit further includes

a blending coefficient calculation unit configured to detect an overlapped area between the projection images of the projection units next to each other, one of the projection units being a target projection unit, and calculate blending coefficients that are used to adjust an overlap between the projection image of the target projection unit and the projection image of the projection unit next to the target projection unit.

13. The projection system according to claim 12, further comprising:

a compensation processing unit configured to generate intermediate images of the projection units from the image as a whole based on the geometric compensation coefficients calculated by the geometric compensation coefficient calculation unit, and calculate final projection images of the projection units from the intermediate images based on the blending coefficients calculated by the blending coefficient calculation unit.

14. The projection system according to claim 1, comprising at least one of:

projection devices serving as the projection units; and

an imaging device configured to capture the correction captured images.

15. An image processing apparatus for causing a plurality of projection units to collectively project an image as a whole on a projection area, the image processing apparatus comprising:

a generation unit configured to generate corrected images including respective correction points which are used for detecting distortions of projection images, which are projected by the respective projection units, based on designated relationships between the projection images of the projection units and the projection area; and

a compensation coefficient calculation unit configured to calculate compensation coefficients, which correspond to the projection units, based on one or more correction captured images that are acquired by capturing the corrected images projected on the projection area,

wherein the generation unit is configured to further generate margin parts in the corrected images, which correspond to the projection units that project the projection images in outer areas of the projection area, in a manner so that parts defining the correction points in the corrected images are projected within the projection area while the parts defining correction points in the corrected images corresponding to the projection units that are next to each other are overlapped.

16. A correction method executed by a computer causing a plurality of projection units to collectively project an image as a whole on a projection area, the correction method comprising:

a generating step of generating corrected images including respective correction points which are used for detecting distortions of projection images, which are projected by the respective projection units, based on designated relationships between the projection images of the projection units and the projection area;

a projection step of causing the projection units to project the generated corrected images;

a receiving step of receiving an input of one or more correction captured images that are acquired by capturing the corrected images projected on the projection area; and

a calculation step of calculating compensation coefficients, which correspond to the projection units, based on the one or more correction captured images;

wherein margin parts are generated in the corrected images, which correspond to the projection units that project the projection images in outer areas of the projection area, in a manner so that parts defining the correction points in the corrected images are projected within the projection area while the parts defining correction points in the corrected images corresponding to the projection units that are next to each other are overlapped.

17. The correction method according to claim 16,

wherein in the generation step, positioning markers are generated in peripheral areas of the parts defining the correction points in the corrected images of the projection units that project the projection images in corner areas of the projection area, the positioning markers defining reference points that are used as marks in positioning in the corner areas of the projection area.

18. The correction method according to claim 17,

wherein in the generation step, a projection target area is defined, to which the image as a whole is collectively projected by the projection units, based on plural reference points which correspond to all corners of the projection area, the reference points being extracted from the one or more correction captured images, and

wherein in the calculation step, the compensation coefficients are calculated, which correspond to the projection units, based on the reference points.