CN113055664A - Automatic trapezoidal correction system and method for projected image - Google Patents
Automatic trapezoidal correction system and method for projected image Download PDFInfo
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- CN113055664A CN113055664A CN202110424950.7A CN202110424950A CN113055664A CN 113055664 A CN113055664 A CN 113055664A CN 202110424950 A CN202110424950 A CN 202110424950A CN 113055664 A CN113055664 A CN 113055664A
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- 238000000034 method Methods 0.000 title claims abstract description 21
- 238000012545 processing Methods 0.000 claims abstract description 23
- 238000004590 computer program Methods 0.000 claims description 3
- 238000003702 image correction Methods 0.000 abstract description 6
- 238000010586 diagram Methods 0.000 description 4
- 238000004891 communication Methods 0.000 description 3
- 238000013459 approach Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N9/00—Details of colour television systems
- H04N9/12—Picture reproducers
- H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
- H04N9/3179—Video signal processing therefor
- H04N9/3185—Geometric adjustment, e.g. keystone or convergence
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Abstract
The invention relates to an automatic trapezoidal correction system and method for a projected image, wherein the system comprises a projection module, a receiving module, a processing module and a correction module; the projection module is used for projecting projection light rays onto a screen to form a projection image; receiving module includes a plurality of photosensitive sensor, accurately frame through photosensitive sensor to the projection effective area and decide, carry out automatic trapezoidal correction to the projecting image through correction module, after accomplishing the trapezoidal correction of projecting image, can realize the maximize and treat the projecting image effectively and demonstrate, carry out the image correction in-process, when guaranteeing that the projecting apparatus fuselage is perpendicular relatively with the position of throwing screen between them, still guarantee to throw light and be located the projection area, throw the range and throw the relapse of angle between them and correct the projecting image, realize that the projecting image is accurate to be corrected fast.
Description
Technical Field
The invention relates to the field of projection correction, in particular to an automatic trapezoidal correction system and method for a projected image.
Background
In the daily use of the projector, the position of the projector is as far as possible perpendicular to the projection screen to ensure the projection effect, and if the position of the projector and the projection screen are not perpendicular to each other, the picture can generate a trapezoid. The trapezoidal correction is to adjust the trapezoidal purpose by adjusting the physical position of the lens, the current automatic trapezoidal correction of the horizontal trapezoidal correction mostly uses a camera to pick up a camera, and a distance sensor is arranged on the projector body, after the relative distance and the included angle between the curtain and the body are measured by the distance sensor, the image before being displayed by a software interpolation algorithm is subjected to shape adjustment and compensation, and the horizontal trapezoidal correction and the vertical trapezoidal correction of a projected image are realized.
The trapezoidal correction method of the projection image applied by the existing projector is difficult to apply to the scene of ultra-short focus projection due to the angle of a camera or a distance sensor arranged on a projector body, and can only correct the projection image into a rectangle as far as possible, but can not accurately frame and identify the boundary of a curtain, namely the effective range of projection, can not ensure that the projection image is displayed to the maximum extent on the effective basis, and even can cause the image to exceed the effective projection range and can not normally acquire the projection image.
Disclosure of Invention
In order to solve the problems of the prior art, the invention provides an automatic trapezoidal correction system for a projected image, which comprises a projection module, a receiving module, a processing module and a correction module; the projection module is used for projecting projection light rays onto a screen to form a projection image; the receiving module comprises a plurality of photosensitive sensors, and all the photosensitive sensors are distributed on the screen and used for sensing projection light projected on the screen; all the photosensitive sensors are connected with the processing module; the processing module is used for judging whether the projected image is in a preset projection effective area formed by all the photosensitive sensors in a surrounding mode according to the state information output by all the photosensitive sensors and outputting a correction instruction according to a judgment result; the correction module is used for automatically correcting the trapezoid of the projection module according to the correction instruction.
The invention has the beneficial effects that: the projection effective area is accurately framed through the photosensitive sensor, after trapezoidal correction of the projected image is completed, the maximized projection image can be effectively displayed, the projection image can be effectively displayed, in the process of image correction, the relative verticality of the positions of the projector body and the projection screen is ensured, the projection light is also ensured to be positioned in the projection area, the projection range and the projection angle of the projection image are repeatedly corrected, and the projected image is accurately and quickly corrected.
On the basis of the technical scheme, the invention can be improved as follows.
Preferably, the state information output by the photosensitive sensor comprises photosensitive state information and non-photosensitive state information.
Preferably, all of the light sensitive sensors are evenly distributed at the edge of the screen.
Preferably, when the state information output by part of the photosensitive sensors is non-photosensitive state information, it is determined that the projected image is offset from the preset projection effective area; when the state information output by all the photosensitive sensors is non-photosensitive state information and when projection light is irradiated on the projection screen, judging that the projection image is in the preset projection effective area; when the state information output by all the photosensitive sensors is non-photosensitive state information and when no projection light is irradiated on the projection screen, judging that the projection image is outside the preset projection effective area;
and when the state information output by all the photosensitive sensors is photosensitive state information, judging that the preset projection effective area is in the projection image.
Preferably, all the photosensitive sensors are in communication connection with the processing module through a wireless network.
Based on the automatic trapezoidal correction system for the projected image, the invention also provides an automatic trapezoidal correction method for the projected image, which comprises the following steps;
s1: projecting the projection light rays onto the screen to form a projection image;
s2: all the photosensitive sensors output state information according to whether the projected light is sensed or not;
s3: judging whether the projected image is in a preset projection effective area formed by all the photosensitive sensors in a surrounding mode according to the state information output by all the photosensitive sensors, and outputting a correction instruction according to a judgment result;
s4; and automatically correcting the trapezoid of the projection image according to the correction instruction.
On the basis of the technical scheme, the invention can be improved as follows.
Preferably, the state information output by the photosensor in S2 includes photosensitive state information and non-photosensitive state information.
Preferably, the preset projection image capturing effective area in S3 includes the screen for capturing the projection image.
Preferably, in S3, it is determined whether the projected image is within a preset projection effective area surrounded by all the photosensors according to the state information output by all the photosensors, specifically, when part of the state information output by the photosensors is non-photosensitive state information, it is determined that the projected image is offset from the preset projection effective area; when the state information output by all the photosensitive sensors is non-photosensitive state information and when projection light is irradiated on the projection screen, judging that the projection image is in the preset projection effective area; when the state information output by all the photosensitive sensors is non-photosensitive state information and when no projection light is irradiated on the projection screen, judging that the projection image is outside the preset projection effective area; and when the state information output by all the photosensitive sensors is photosensitive state information, judging that the preset projection effective area is in the projection image.
Based on the automatic keystone correction method for the projected image, the invention further provides a computer storage medium comprising a memory, wherein a computer program is stored in the memory, and when the computer program is executed by a processor, the automatic keystone correction method for the projected image is realized.
Drawings
FIG. 1 is a flow chart of an automatic keystone rectification system for projected images according to the present invention;
FIG. 2 is a schematic diagram of a projection image of an automatic keystone correction system for a projected image according to the present invention;
FIG. 3 is a schematic diagram of a projection image of an automatic keystone correction system for a projected image according to the present invention;
FIG. 4 is a schematic diagram of an image after the automatic keystone correction system for projected images finishes correcting;
FIG. 5 is a schematic view of a projection image of an automatic keystone correction system for a projected image according to the present invention;
FIG. 6 is a flow chart of an automatic keystone correction method for projected images according to the present invention;
FIG. 7 is a schematic diagram of the operation of the automatic keystone correction method for projected images according to the present invention.
Detailed Description
The principles and features of this invention are described below in conjunction with the following drawings, which are set forth by way of illustration only and are not intended to limit the scope of the invention.
As shown in FIG. 1, the present invention provides an automatic keystone rectification system for a projected image, which comprises a projection module, a receiving module, a processing module and a rectification module; the projection module is used for projecting projection light rays onto a screen to form a projection image; the receiving module comprises a plurality of photosensitive sensors, and all the photosensitive sensors are distributed on the screen and used for sensing projection light projected on the screen; all the photosensitive sensors are connected with the processing module; the processing module is used for judging whether the projected image is in a preset projection effective area formed by all the photosensitive sensors in a surrounding mode according to the state information output by all the photosensitive sensors and outputting a correction instruction according to a judgment result; the correction module is used for automatically correcting the trapezoid of the projection module according to the correction instruction.
The projection effective area is accurately framed by the photosensitive sensor, the maximum and effective display of the projection image can be realized after the trapezoidal correction of the projection image is completed, the projection light is ensured to be positioned in the projection area while the relative vertical position of the projector body and the projection screen is ensured in the image correction process, the projection range and the projection angle of the projection image are repeatedly corrected, and the accurate and rapid correction of the projection image is realized.
In the present embodiment, the state information output by the photosensitive sensor includes photosensitive state information and non-photosensitive state information. The photosensitive sensors are 4 in one group and at least comprise a group of photosensitive sensors which are uniformly distributed at the edge or the vertex of the screen, the photosensitive sensors distinguish ambient light and projection light with specific wavelength according to the wavelength of different light, when the interference of the ambient light is avoided, the projection light irradiates the photosensitive sensors, the state information output by the photosensitive sensors is photosensitive state information, and when the photosensitive sensors do not acquire the projection light or only acquire the ambient light, the state information output by the photosensitive sensors is non-photosensitive state information.
In this embodiment, specifically, all the photosensitive sensors are in communication connection with the processing module through a wireless network, all the photosensitive sensors send status information to the processing module through the wireless network, and the processing module determines whether the projected image needs keystone correction according to the status information output by the photosensitive sensors. Assuming that n photosensitive sensors exist, when the state information output by the photosensitive sensors which is more than or equal to 1 and less than or equal to n-1 is non-photosensitive state information, judging that the projection image deviates from the preset projection effective area; when the state information output by the n photosensitive sensors is non-photosensitive state information and when projection light is irradiated on the projection screen, judging that the projection image is in the preset projection effective area; when the state information output by the n photosensitive sensors is non-photosensitive state information and no projection light is irradiated on the projection screen, judging that the projection image is outside the preset projection effective area; and when the state information output by the n photosensitive sensors is photosensitive state information, judging that the projected image is in the preset projection effective area. As shown in the figure, the preset projection effective area is a rectangle (abcd), and the actual projection area of the projection light is a rectangle (efgh).
In this embodiment, specifically, in the actual projection imaging application process of the projector, as shown in fig. 2, when the actual projection area of the projection light is located in the preset projection effective area, the photosensors located at the edge of the projection screen are all in an unexposed state, at this time, when the processing module receives that the output state information of all the photosensors is in an unexposed state, when the projection screen is irradiated by the projection light, it is determined that the projection image is within the preset projection effective area, and when the projection screen is not irradiated by the projection light, it is determined that the projection image is outside the preset projection effective area, and the photosensitive sensor is used to detect whether the projection screen is irradiated by the projection light, so that the processing module sends a correction instruction to the projection module, so that the actual projection area (efgh) of the projection light continuously "approaches" the preset projection effective area (abcd), until all the photosensitive sensors located at the edge of the projection screen are in a photosensitive state for the first time, that is, as shown in fig. 4, after the actual projection area (efgh) of the projection light and the preset projection effective area (abcd) are substantially overlapped, the image correction is completed.
As shown in fig. 3, when the actual projection area of the projection light is located in the preset projection effective area, the portion of the photosensor located at the edge of the projection screen is in an unexposed state, and at this time, the processing module receives a portion of the output state information of the photosensor, which is in an unexposed state, and another portion of the output state information of the photosensor, which is in a photosensitive state, and determines that the projection image exceeds the preset projection effective area, and the processing module sends a correction instruction to the projection module, so that the photosensor originally in the photosensitive state is in the unexposed state for the first time, and after the photosensor originally in the unexposed state is in the photosensitive state, as shown in fig. 4, the actual projection area (efgh) of the projection light and the preset projection effective area (abcd) are substantially overlapped, and then image correction is completed.
As shown in fig. 5, when the preset projection effective area is located in the projection light actual projection area, the photosensors located at the edge of the projection screen are all in a photosensitive state, and at this time, the processing module receives that the output state information of all the photosensors is non-photosensitive state information, and determines that the projection image is located in the preset projection effective area, and the processing module sends a correction instruction to the projection module, so that the photosensors originally in the photosensitive state are in the non-photosensitive state for the first time, and after the photosensors originally in the non-photosensitive state are in the photosensitive state, as shown in fig. 4, the projection light actual projection area (efgh) and the preset projection effective area (abcd) are basically overlapped, and then image correction is completed;
as shown in fig. 6, the present invention further provides an automatic keystone correction method for a projected image, comprising the following steps;
s1: projecting the projection light rays onto the screen to form a projection image;
s2: all the photosensitive sensors output state information according to whether the projected light is sensed or not;
s3: judging whether the projected image is in a preset projection effective area formed by all the photosensitive sensors in a surrounding mode according to the state information output by all the photosensitive sensors, and outputting a correction instruction according to a judgment result;
s4; and automatically correcting the trapezoid of the projection image according to the correction instruction.
In this embodiment, as shown in fig. 7, after the projector is started, the projector projects projection light onto the screen to form a projection image, and then triggers the projector to perform automatic keystone correction on the projection image; when a photosensitive sensor arranged at the edge of a preset effective projection area is irradiated by projected light, the state information output by the photosensitive sensor is photosensitive state information, and when the photosensitive sensor does not acquire the projected light or only acquires ambient light, the state information output by the photosensitive sensor is non-photosensitive state information; all the photosensitive sensors are in communication connection with the processing module, namely the host through a wireless network, all the photosensitive sensors send state information to the host through the wireless network, when the host judges whether the projected image is in a preset projection effective area formed by all the photosensitive sensors according to the state information output by the photosensitive sensors, and after judging whether the projected image needs to be corrected in a trapezoidal manner, sending a correction instruction to the projection module to correct or complete automatic trapezoidal correction, the criteria for judging whether the projected image is in the preset projection effective area formed by all the photosensitive sensors and judging whether the projected image needs to be subjected to trapezoid correction are specifically, when part of the state information output by the photosensitive sensor is non-photosensitive state information, judging that the projected image deviates from the preset projection effective area; when the state information output by all the photosensitive sensors is the non-photosensitive state information, judging that the projected image is in the preset projection effective area or judging that the projected image is outside the preset projection effective area; and when the state information output by all the photosensitive sensors is photosensitive state information, judging that the preset projection effective area is in the projection image.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (10)
1. An automatic trapezoidal correction system for a projected image is characterized by comprising a projection module, a receiving module, a processing module and a correction module;
the projection module is used for projecting projection light rays onto a screen to form a projection image;
the receiving module comprises a plurality of photosensitive sensors, and all the photosensitive sensors are distributed on the screen and used for sensing projection light projected on the screen; all the photosensitive sensors are connected with the processing module;
the processing module is used for judging whether the projected image is in a preset projection effective area formed by all the photosensitive sensors in a surrounding mode according to the state information output by all the photosensitive sensors and outputting a correction instruction according to a judgment result;
the correction module is used for automatically correcting the trapezoid of the projection module according to the correction instruction.
2. The automatic keystone correction system for a projected image of claim 1, wherein the status information output by the light sensitive sensor includes light sensitive status information and light insensitive status information.
3. The automatic keystone correction system for a projected image of claim 1, wherein all of said light sensitive sensors are evenly distributed at the edges of said screen.
4. The automatic keystone rectification system of claim 2 wherein the processing module is further configured to,
when part of the state information output by the photosensitive sensor is non-photosensitive state information, judging that the projected image deviates from the preset projection effective area;
when the state information output by all the photosensitive sensors is non-photosensitive state information and when projection light is irradiated on the projection screen, judging that the projection image is in the preset projection effective area;
when the state information output by all the photosensitive sensors is non-photosensitive state information and when no projection light is irradiated on the projection screen, judging that the projection image is outside the preset projection effective area;
and when the state information output by all the photosensitive sensors is photosensitive state information, judging that the projected image is in the preset projection effective area.
5. The automatic keystone rectification system for projected images of claims 1 through 4 wherein all of said light sensitive sensors are communicatively coupled to said processing module via a wireless network.
6. An automatic keystone correction method for a projected image, wherein the automatic keystone correction method for a projected image using the automatic keystone correction system for a projected image according to any one of claims 1 to 5 includes the steps of;
s1: projecting projection light rays onto a screen to form a projection image, wherein a plurality of photosensitive sensors used for sensing the projection light rays are distributed on the screen;
s2: judging whether the projected image is in a preset projection effective area formed by all the photosensitive sensors in a surrounding mode according to the state information output by all the photosensitive sensors, and outputting a correction instruction according to a judgment result;
s3; and automatically correcting the trapezoid of the projection image according to the correction instruction.
7. The automatic keystone correction method of a projected image of claim 6, wherein the status information output by the light sensor includes light-sensitive status information and non-light-sensitive status information.
8. The method for automatically keystone correction of a projected image of claim 6, wherein all of said light sensitive sensors are evenly distributed at the edges of said screen.
9. The automatic keystone correction method for a projected image according to claim 7, wherein it is determined whether the projected image is within a predetermined projection effective area surrounded by all the photosensors according to the status information outputted from all the photosensors,
when part of the state information output by the photosensitive sensor is non-photosensitive state information, judging that the projected image deviates from the preset projection effective area;
when the state information output by all the photosensitive sensors is non-photosensitive state information and when projection light is irradiated on the projection screen, judging that the projection image is in the preset projection effective area;
when the state information output by all the photosensitive sensors is non-photosensitive state information and when no projection light is irradiated on the projection screen, judging that the projection image is outside the preset projection effective area;
and when the state information output by all the photosensitive sensors is photosensitive state information, judging that the projected image is in the preset projection effective area.
10. A computer-readable storage medium characterized by: comprising a memory in which a computer program is stored which, when being executed by a processor, carries out a method for automatic keystone correction of a projected image as claimed in any one of claims 6 to 9.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110424950.7A CN113055664A (en) | 2021-04-20 | 2021-04-20 | Automatic trapezoidal correction system and method for projected image |
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| CN202110424950.7A CN113055664A (en) | 2021-04-20 | 2021-04-20 | Automatic trapezoidal correction system and method for projected image |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN116577593A (en) * | 2023-07-05 | 2023-08-11 | 深圳清大电子科技有限公司 | Effective touch area measuring instrument for intelligent screen |
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Application publication date: 20210629 |