US-12627780-B2 - Method for adjusting projection boundary and projection system

US12627780B2US 12627780 B2US12627780 B2US 12627780B2US-12627780-B2

Abstract

A method for adjusting a projection boundary and a projection system are provided. Multiple imaging apparatuses corresponding to multiple projection apparatuses are driven, and each imaging apparatus obtains a corresponding captured image by capturing projected image projected by corresponding one projection apparatus and surrounding area of the projected image. All captured images are displayed on a display, and a main bounding box corresponding to each projected image and a reference bounding box corresponding to the surrounding area are displayed on each captured image. The main bounding box of each captured image is independently adjusted relative to the reference bounding box to obtain an adjusted main bounding box. A full image boundary is calculated based on the respective adjusted main bounding boxes. The projection apparatuses are driven to project an adjusted full image based on the full image boundary.

Inventors

Chia-Yen Ou
Hsun-Cheng Tu
Chien-Chun Peng
KANG-SHUN HSU

Assignees

CORETRONIC CORPORATION

Dates

Publication Date: 20260512
Application Date: 20230920
Priority Date: 20220923

Claims (16)

1 . A method for adjusting a projection boundary, performed by a processor, comprising steps of: driving a plurality of projection apparatuses to respectively project respective projected images on different positions of a projection surface to form a full image; in response to projecting the projected images on the projection surface, driving a plurality of imaging apparatuses corresponding to the plurality of projection apparatuses and using each of the imaging apparatuses to obtain a corresponding captured image by capturing the projected image projected by corresponding one of the projection apparatus and a surrounding area of the projected image, wherein the surrounding area of the projected image comprises at least a part of another of the projected images projected by another of the projection apparatuses; displaying all captured images from the imaging apparatuses on a display, and respectively displaying a main bounding box corresponding to the projected image on each of the captured images and displaying a reference bounding box corresponding to at least a part of the another of the projected images in the surrounding area on each of the captured images; independently adjusting the main bounding box of each of the captured images relative to the reference bounding box to obtain an adjusted main bounding box corresponding to each of the captured images; calculating a full image boundary based on respective adjusted main bounding boxes of the captured images; and driving the projection apparatuses to project an adjusted full image based on the full image boundary, wherein the step of calculating the full image boundary based on the respective adjusted main bounding boxes of the captured images comprises: calculating coordinate information of the respective adjusted main bounding boxes of the captured images obtained by the imaging apparatuses to obtain a minimum intersection area, and using an outer frame of the minimum intersection area as the full image boundary; or calculating coordinate information of the respective adjusted main bounding boxes of the captured images to obtain a maximum intersection area, and using an outer frame of the maximum intersection area as the full image boundary.
2 . The method for adjusting a projection boundary according to claim 1 , wherein a first projection apparatus among the projection apparatuses corresponds to a first imaging apparatus of the imaging apparatuses, and the first projection apparatus is configured to project a first projected image, wherein the step of respectively displaying the main bounding box corresponding to the projected image on each of the captured images comprises: calculating a first projection boundary range in which the first projected image is presented on the captured image; and displaying the main bounding box within the first projection boundary range.
3 . The method for adjusting a projection boundary according to claim 1 , wherein the step of displaying the reference bounding box corresponding to at least a part of the another of the projected images in the surrounding area on each of the captured images comprises: calculating a second projection boundary range corresponding to the surrounding area, which is adjacent to the first projected image; and displaying the reference bounding box within the second projection boundary range.
4 . The method for adjusting a projection boundary according to claim 2 , wherein the step of independently adjusting the main bounding box of each of the captured images relative to the reference bounding box comprises: adjusting at least one side of the main bounding box to align with at least one side of the reference bounding box in a manner that the main bounding box does not exceed the first projection boundary range.
5 . The method for adjusting a projection boundary according to claim 1 , wherein the step of driving the projection apparatuses to respectively project the respective projected images on different positions of the projection surface comprises: projecting an initial bounding box corresponding to each of the projected images while driving the projection apparatuses to respectively project the respective projected images on different positions of the projection surface, wherein each of the imaging apparatuses captures the initial bounding box projected within an imaging range to present the main bounding box and the reference bounding box on the captured image.
6 . The method for adjusting a projection boundary according to claim 1 , wherein after respectively displaying the main bounding box corresponding to the projected image on each of the captured images, the method further comprises step of: providing a plurality of control points on the main bounding box of the captured image, and obtaining the adjusted main bounding box by moving at least one of the control points.
7 . The method for adjusting a projection boundary according to claim 6 , wherein moving at least one of the control points comprises: moving at least one of the control points onto the reference bounding box on the captured image.
8 . The method for adjusting a projection boundary according to claim 1 , wherein the step of driving the projection apparatuses to project the adjusted full image based on the full image boundary comprises: obtaining adjusted projection boundary coordinates corresponding to each of the projection apparatuses under the full image boundary; and transforming the adjusted projection boundary coordinates to conform to a coordinate system of each of the projection apparatuses, and driving each of the projection apparatuses to project the adjusted full image on the projection surface.
9 . A projection system, comprising a plurality of projection apparatuses, a plurality of imaging apparatuses, a display, and a processor, wherein the projection apparatuses are coupled to the processor, and the projection apparatuses are driven by the processor to respectively project respective projected images on different positions of a projection surface to form a full image; the imaging apparatuses are respectively disposed corresponding to the projection apparatuses and are coupled to the processor, and the imaging apparatuses are driven by the processor to enable each of the imaging apparatuses to obtain a corresponding captured image by capturing the projected image projected by corresponding one of the projection apparatus and a surrounding area of the projected image, wherein the surrounding area of the projected image comprises at least a part of another of the projected images projected by another of the projection apparatuses; the display is coupled to the processor, and the processor receives all captured images from the imaging apparatuses and transmits the captured images to the display to display the captured images; wherein the processor is configured to: respectively display a main bounding box corresponding to the projected image on each of the captured images and display a reference bounding box corresponding to at least a part of the another of the projected images in the surrounding area on each of the captured images; independently adjust the main bounding box of each of the captured images relative to the reference bounding box to obtain an adjusted main bounding box corresponding to each of the captured images; calculate a full image boundary based on respective adjusted main bounding boxes of the captured images; and drive the projection apparatuses to project an adjusted full image based on the full image boundary, wherein the processor is configured to: calculate coordinate information of the respective adjusted main bounding boxes of the captured images obtained by the imaging apparatuses to obtain a minimum intersection area, and use an outer frame of the minimum intersection area as the full image boundary; or calculate coordinate information of the respective adjusted main bounding boxes of the captured images to obtain a maximum intersection area, and use an outer frame of the maximum intersection area as the full image boundary.
10 . The projection system according to claim 9 , wherein a first projection apparatus among the projection apparatuses corresponds to a first imaging apparatus of the imaging apparatuses, the first projection apparatus is configured to project a first projected image, and the processor is configured to calculate a first projection boundary range in which the first projected image is presented on the captured image; and display the main bounding box within the first projection boundary range by the display.
11 . The projection system according to claim 10 , wherein the processor is configured to calculate a second projection boundary range corresponding to the surrounding area, which is adjacent to the first projected image, and display the reference bounding box within the second projection boundary range by the display.
12 . The projection system according to claim 9 , wherein the processor is configured to: project an initial bounding box corresponding to each of the projected images while driving the projection apparatuses to respectively project the respective projected images on different positions of the projection surface, wherein each of the imaging apparatuses captures the initial bounding box projected within an imaging range to present the main bounding box and the reference bounding box on the captured image.
13 . The projection system according to claim 10 , wherein the processor is configured to adjust at least one side of the main bounding box to align with at least one side of the reference bounding box by the display in a manner that the main bounding box does not exceed the first projection boundary range.
14 . The projection system according to claim 9 , wherein the processor is configured to: provide a plurality of control points on the main bounding box of the captured image, and obtain the adjusted main bounding box by moving at least one of the control points.
15 . The projection system according to claim 14 , wherein the processor is configured to: move at least one of the control points onto the reference bounding box on the captured image.
16 . The projection system according to claim 9 , wherein the processor is configured to: obtain adjusted projection boundary coordinates corresponding to each of the projection apparatuses under the full image boundary; and transform the adjusted projection boundary coordinates to conform to a coordinate system of each of the projection apparatuses, and drive each of the projection apparatuses to project the adjusted full image on the projection surface.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application claims the priority benefit of China application serial no. 202211163843.4, filed on Sep. 23, 2022. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification. BACKGROUND Technical Field The disclosure relates to a projection system and a projection method, and particularly relates to a method for adjusting a projection boundary and a projection system. Description of Related Art Projectors are constantly evolving for business, home or education applications, and it becomes more and more common to use multiple projectors to project at the same time to form a larger image. Generally speaking, in an automatic stitching process, the stitched projection area is defined by pre-boundary. It is a conventional approach to use a single camera for imaging with pre-boundary. Since a single camera does not involve multi-camera coordinate conversion which is required when multiple cameras are used, it is easy to define the projection range by using the pre-view function of the application. For example, the projection boundary of multiple projectors may be preset through the application, and then the projection areas are stitched based on the boundary. Moreover, in the case of presetting the boundary for imaging with multiple cameras, in order to obtain a result similar to that obtained by each camera, the multiple images captured need to be stitched first to obtain a complete stitched image so as to define the boundary. Since the multiple cameras can only capture images within their respective ranges, the captured images shown on the interface of the application are not integral images. Therefore, in the conventional approach, it is necessary to perform image stitching on the application first for the user to know the final overall image, so that the boundary can be adjusted. Since it involves complex calculation to stitch images on the application, it usually takes more time (for example, 1 hour or longer), which is quite inconvenient for the user. Besides, when the boundary is adjusted with use of multiple cameras, the projection boundary may not be aligned due to the different perspectives of the cameras. The information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Further, the information disclosed in the Background section does not mean that one or more problems to be resolved by one or more embodiments of the invention was acknowledged by a person of ordinary skill in the art. SUMMARY The disclosure provides a method for adjusting a projected image and a projection system that are capable of adjusting a projection boundary as coordinate data for applying boundary setting in subsequent automatic image blending. Other objectives and advantages of the disclosure can be further understood from the technical features described in the disclosure. In order to achieve one or some or all of the above objectives or other objectives, a method for adjusting a projection boundary according to an embodiment of the disclosure is performed by a processor, and the method includes: driving a plurality of projection apparatuses to respectively project respective projected images on different positions of a projection surface to form a full image; in response to projecting the projected images on the projection surface, driving a plurality of imaging apparatuses corresponding to the projection apparatuses and using each of the imaging apparatuses to obtain a corresponding captured image by capturing the projected image projected by the corresponding one of the projection apparatuses and a surrounding area of the projected image, the surrounding area of the projected image including at least a part of another of the projected images projected by another of the projection apparatuses; displaying all captured images from the imaging apparatuses on a display, and respectively displaying a main bounding box corresponding to the projected image on each of the captured images and displaying a reference bounding box corresponding to at least a part of the another of the projected images in the surrounding area on each of the captured images; independently adjusting the main bounding box of each of the captured images relative to the reference bounding box to obtain an adjusted main bounding box corresponding to each of the captured images; calculating a full image boundary based on respective adjusted main bounding boxes of the captured images; and driving the projection apparatuses to project an adjusted full image based on the full image boundary. A projection system according to an embodiment of the disclosure includes a plurality of projection apparatuses, a plurality of imaging apparatuses, a