JP5347488B2 - Projection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projector for correcting an input image about a color or a pattern on a projection surface without sharply reducing visibility of the projected image. <P>SOLUTION: The projector includes an image processing part 101A which detects the reflectance distribution of the projection surface, corrects the detected reflectance distribution on the basis of the input image, smoothes the corrected reflectance distribution, corrects the input image on the basis of the detected reflectance distribution and the smoothed reflectance distribution, and projects the corrected input image to the projection surface by using a projection unit 110. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a projection apparatus.

Miniaturization of the projection device makes it easy to carry the projection device, and increases the chance of projecting an image on a projection surface other than the screen, such as a wall of a room. However, when a projection surface other than the screen has a color or pattern, when the image is projected onto the projection surface, the visibility of the projected image is deteriorated due to the influence of the color or pattern of the projection surface. Therefore, a technique for projecting an image corrected according to the reflectance distribution on the projection surface so that the color or pattern of the projection surface is not visible on the projection surface on which the image is projected is known as a conventional technique (for example, Patent Documents 1, 2).
JP 2008-67080 A JP 2007-322671 A

  When the input image is corrected by the conventional technique as described in Patent Document 1 or Patent Document 2, when a portion with extremely low reflectance such as a black line or a black point exists on the projection surface, the image projected on the projection surface The brightness of the screen may be significantly reduced. For this reason, there is a problem that the visibility of the projected image may be deteriorated by the correction of the input image.

The projection device according to the first aspect of the present invention provides a reflectance distribution detecting means for detecting the reflectance distribution on the projection surface by capturing the projected black image and white image, an image input means for inputting an input image, and correction impossible distribution calculating means for calculating a correction impossible distribution by comparing the corresponding normalized pixel values of said detected reflectance distribution of normalized pixel value and the input image by the reflectance distribution detecting means When the correction impossible distribution and reflectivity distribution smoothing means for smoothing kernel area of the correction impossible distribution of predetermined size calculated by the calculating means, smoothed smoothed correction impossible by the reflectivity distribution smoothing means Input image correction means for correcting the input image based on the distribution; and projection means for projecting the input image corrected by the input image correction means onto the projection plane. And features.

  According to the present invention, it is possible to correct an input image with respect to a color or a pattern on a projection plane without significantly reducing the visibility of a projected image.

  Hereinafter, an embodiment for carrying out the present invention will be described with reference to the drawings. The projection apparatus according to the present invention corrects the input image according to the state of the projection plane in order to improve the appearance and visibility of the projected image.

  FIG. 1 is a view of a projection apparatus 1 according to an embodiment of the present invention as seen from the front. As shown in FIG. 1, a projection lens 111A constituting a projection optical system 111 (see FIG. 2) and a photographing lens 121A constituting an imaging optical system 121 (see FIG. 2) are provided on the front of the projection apparatus 1. It has been. The projection device 1 projects an image or the like from a built-in projection unit 110 (see FIG. 2) toward a front screen or the like while being placed on a desk or the like.

  FIG. 2 is a block diagram illustrating the configuration of the projection apparatus 1. In FIG. 2, the projection apparatus 1 includes a projection unit 110, an imaging unit 120, a control circuit 101, a memory 102, an operation unit 103, an external interface (I / F) circuit 104, and a memory card interface (I / F). ) 105, and a memory card 150 is connected to the memory card interface 105.

  The control circuit 101 includes a microprocessor and its peripheral circuits. The control circuit 101 performs a predetermined calculation using signals input from the respective units in the projection apparatus based on the control program. The control circuit 101 outputs the calculation result as a control signal to each part in the projection apparatus, and controls the projection operation and the imaging operation of the projection apparatus 1. The control program is stored in a ROM (not shown) in the control circuit 101.

  The control circuit 101 includes an image processing unit 101A. The image processing unit 101A performs image processing on image data acquired via the external interface 104 or image data acquired from the memory card 150. Details of the image processing performed by the image processing unit 101A will be described later.

  The memory 102 is used as a working memory for the control circuit 101. The operation unit 103 includes buttons and switches, and outputs operation signals corresponding to the operated buttons and switches to the control circuit 101. The memory card 150 can write, store, and read data according to instructions from the control circuit 101.

  The projection unit 110 includes a projection optical system 111, a liquid crystal panel 112, an LED light source 113, and a projection control circuit 114. The LED light source 113 illuminates the liquid crystal panel 112 with brightness according to the supply current. The liquid crystal panel 112 generates a light image according to the drive signal from the projection control circuit 114. The projection optical system 111 projects a light image emitted from the liquid crystal panel 112. The projection control circuit 114 outputs a control signal to the LED light source 113 and the liquid crystal panel 112 according to an instruction from the control circuit 101.

  The projection unit 110 projects an image instructed from the control circuit 101. The projection unit 110 can project an image based on image data supplied from an external device via the external interface circuit 104 in addition to the image data stored in the memory card 150. An image of image data stored in the memory card 150 or an image of image data supplied from an external device via the external interface circuit 104 is hereinafter referred to as an input image.

  The imaging unit 120 includes an imaging optical system 121, an imaging element 122, and an imaging control circuit 123, and images a projection plane according to an instruction from the control circuit 101. The imaging optical system 121 forms a subject image on the imaging surface of the imaging element 122. The image sensor 122 converts the subject image into an electrical signal. As the image sensor 122, a CCD, a CMOS image sensor, or the like is used. The imaging control circuit 123 drives and controls the imaging element 122 according to an instruction from the control circuit 101 and performs predetermined signal processing on the electrical signal output from the imaging element 122.

  Next, image processing performed by the image processing unit 101A of the control circuit 101 will be described. In the image processing according to the embodiment of the present invention, the input image is corrected based on the image of the projection plane captured by the imaging unit 120 so that the pattern and dirt on the projection plane are not noticeable when the input image is projected onto the projection plane. I do.

  The image processing performed by the image processing unit 101A will be described with reference to the flowchart of FIG. The processing in FIG. 3 is executed in the image processing unit 101A by a program that starts when the projection apparatus 1 starts processing for starting projection.

  In step S1, an image representing the reflectance of the projection surface is calculated. In step S <b> 2, the image data of the input image is read from the external interface circuit 104 or from the memory card 150 and stored in the memory 102. In step S3, an uncorrectable distribution is calculated. The uncorrectable distribution is a distribution of a low reflectance portion of the projection surface that is difficult to be made invisible by correcting the input image. It is difficult to prevent a portion with low reflectance from being seen through the projected image without greatly reducing the brightness of the projected image.

  In step S4, the uncorrectable distribution is smoothed. In step S5, the input image read in step S2 is corrected based on the smoothed uncorrectable distribution and the image representing the reflectance of the projection surface. In step S6, the input image corrected in step S5 is converted into an analog signal, and the corrected input image is projected. In step S7, it is determined whether there is an input image to be projected next. If there is an input image to be projected next, affirmative determination is made in step S7, and the process returns to step S2. If there is no input image to be projected next, a negative determination is made in step S7, and the image processing ends.

  Next, steps S1, S3, S4, and S5 of the flowchart of FIG. 3 will be described in detail.

-Calculation of image representing reflectance of projection surface-
With reference to the flowchart of FIG. 4, the calculation process of the image showing the reflectance of the projection surface in step S1 will be described. When an input image whose i-th pixel value is given by (R, G, B) _i is projected by the projection unit 110, a pixel value corresponding to the i-th pixel value in the captured image of the projection plane is represented by (R _P , Let G _P , B _P ) _i .

In step S11, a black image ((R, G, B) _i = (0, 0, 0) _i ) is projected onto the projection plane. In step S12, the projection plane on which the black image is projected is photographed. The pixel value of the captured image A01 at this time is (R _P , G _P , B _P ) _i = (R _A01 , G _A01 , B _A01 ) _i .

In step S13, a white image ((R, G, B) _i = (255, 255, 255) _i ) is projected onto the projection plane. In step S14, the projection plane on which the white image is projected is photographed. The pixel value of the photographed image A02 at this time is (R _P , G _P , B _P ) _i = (R _A02 , G _A02 , B _A02 ) _i .

In step S15, an image A03 representing the reflectance of the projection plane is calculated from the difference between the captured image A02 and the captured image A01. Specifically, an image of (R _A03 , G _A03 , B _A03 ) _i = (R _A02 −R _A01 , G _A02 −G _A01 , B _A02 −B _A01 ) _i is calculated.

-Uncorrectable distribution calculation-
With reference to the flowchart of FIG. 5, the calculation process of the uncorrectable distribution performed in step S3 of FIG. 3 will be described.

In step S21, the pixel value of the input image is normalized. In the case of 8-bit image data, the pixel value is divided by 255. That is, the i-th normalized pixel value of the input image is (R _B01 , G _B01 , B _B01 ) _i = (R / 255, G / 255, B / 255) _i . In step S22, the pixel value of the image representing the reflectance of the projection surface is normalized. The maximum value of the pixel values _{R A03,} G _{A03, B A03} in the image A03 _{R MAX,} G _MAX, When _{B MAX,} i th normalized pixel values of the image A03 representing the reflectance of the projection plane, ( R _B02 , G _B02 , B _B02 ) _i = (R / R _MAX , G / G _MAX , B / B _MAX ) _i

  In step S23, it is determined whether or not the normalized pixel value of the input image is larger than the normalized pixel value of the image A03 representing the reflectance of the projection surface. When the normalized pixel value of the input image is larger than the normalized pixel value of the image A03 representing the reflectance of the projection surface, an affirmative determination is made in step S23 and the process proceeds to step S24. If the normalized pixel value of the input image is equal to or less than the normalized pixel value of the image A03 representing the reflectance of the projection surface, a negative determination is made in step S23, and the process proceeds to step S25.

In step S24, the uncorrectable distribution values B B03 (R _B03 , G _B03 , B _B03 ) _i of the uncorrectable distribution values R _B03 , G _B03 , B _B03 are used as the normalized pixel values of the image A03 representing the reflectance of the projection plane. Let R _B02 , _B02 , B _B02 . In step S25, the uncorrectable distribution values R _B03 , G _B03 , and B _B03 of the uncorrectable distribution B03 (R _B03 , G _B03 , B _B03 ) _i are set to 1. For example, if the i-th normalized pixel value of the input image is R _B01 > R _B02 , G _B01 <G _B02 , B _B01 > B _B02 , the uncorrectable distribution B03 (R _B03 , G _B03 , B _B03 ) _i becomes (R _B02 , 1, B _B02 ) _i .

  In step S26, it is determined whether or not the comparison in step S23 has been completed for all pixels of the input image. When the comparison in step S23 is completed for all the pixels of the input image, an affirmative determination is made in step S26, and the calculation process of the uncorrectable distribution is terminated. If all the pixels of the input image have not been compared in step S23, a negative determination is made in step S26, and the process returns to step S23.

  The calculation process of the uncorrectable distribution B03 will be specifically described with reference to FIG. FIG. 6A shows an input image. FIG. 6B is a diagram showing the reflectance distribution on the projection surface. Comparing the image B01 normalized from the input image shown in FIG. 6A with the image B02 normalized from the image A03 representing the reflectance distribution shown in FIG. 6B, the uncorrectable distribution B03 is calculated. An uncorrectable distribution B03 shown in FIG.

-Uncorrectable distribution smoothing process-
With reference to the flowchart of FIG. 7, the uncorrectable distribution smoothing process in step S4 of FIG. 3 will be described.

  In step S31, a low pass filter (smoothing filter) is applied to the uncorrectable distribution B03 to smooth the uncorrectable distribution. With reference to FIG. 8, a description will be given by taking as an example the smoothing of an uncorrectable distribution performed in a 3 × 3 kernel (local region used for weighted average calculation). The pixel at the center of the 3 × 3 pixels is the target pixel, and the uncorrectable distribution value at the target pixel is 0.3. The uncorrectable distribution values of the pixels adjacent to the target pixel are 1.0, 0.8, 1.0, 0.6, 0.5, 0.5, 0.7, and 0.9. When the weighted average calculation is performed on the uncorrectable distribution value of the target pixel and the uncorrectable distribution value of the pixel adjacent to the target pixel, that is, the uncorrectable distribution value of the target pixel and the uncorrectable distribution value of the pixel adjacent to the target pixel are 1 When the weighting of / 9 is added and added, the uncorrectable distribution value of the target pixel after smoothing is calculated, and the value becomes 0.7.

  Note that the size of the kernel (the local region used for the weighted average calculation) can be appropriately selected depending on the appearance when the corrected input image is projected. For example, it may be 9 × 9 or 13 × 13. Further, the smoothing process may be performed by a median filter instead of the low pass filter.

  In step S32, the smoothed uncorrectable distribution is blocked. Hereinafter, the smoothed non-correctable distribution is referred to as a smooth non-correctable distribution. Non-smooth correction distribution is divided into non-smooth correction distributions in a predetermined area, and the correction with the smallest value among the non-correctable distribution values of pixels included in one divided area (one block). This is a process of setting the impossible distribution value to the correction impossible distribution value of the pixels included in the region. With reference to FIG. 9, the process of blocking when 6 × 6 pixels are made one block will be described. As shown in FIG. 9A, the non-correctable distribution value having the smallest value in the 6 × 6 pixels, that is, in one block is 0.5. Therefore, when the blocking process is performed, as shown in FIG. 9B, all the non-correctable distribution values of the pixels included in one block are 0.5.

  In step S33, a smoothing correction impossible distribution is performed by applying a low-pass filter to the blocked smooth correction impossible distribution. The kernel size in the smoothing process is set larger than the kernel size in the smoothing process in step S31. For example, 101 × 101 to 201 × 201. Hereinafter, the smoothed non-smoothable distribution that has been blocked is referred to as a luminance value reduction magnification distribution.

  With reference to FIG. 10, the uncorrectable distribution smoothing process will be specifically described. FIG. 10A is a diagram illustrating a smooth correction impossible distribution obtained by smoothing the correction impossible distribution of FIG. The size of the kernel when smoothing is 9 × 9. FIG. 10B is a diagram showing the smooth correction impossible distribution of FIG. One block is composed of 20 × 30 pixels. FIG. 10C is a diagram illustrating a luminance value reduction magnification distribution obtained by further smoothing the blocked smooth correction impossible distribution of FIG. 10B.

-Correction of input image-
With reference to the flowchart of FIG. 11, the correction process of the input image in step S5 of FIG. 3 will be described.

In step S41, the input image is multiplied by the luminance value reduction magnification distribution. For example, when the i-th pixel value of the input image is (R, G, B) _i and the uncorrectable distribution value at the i-th pixel of the luminance value reduction magnification distribution is (α, β, γ) _i , The value at the i-th pixel of the image obtained by multiplying the input image by the luminance value reduction magnification distribution is (Rα, Gβ, Bγ) _i .

In step S42, an image obtained by multiplying the input image by the luminance value reduction magnification distribution is further divided by an image representing the reflectance of the projection plane. For example, the value of the i-th pixel of the image obtained by multiplying the input image by the luminance value reduction magnification distribution is (Rα, Gβ, Bγ) _i , and the pixel value of the i-th pixel of the image representing the reflectance of the projection plane is (R _A03 , G _A03 , B _A03 ) If _i , the ratio of the two images obtained by dividing the input image multiplied by the luminance value reduction magnification distribution by the pixel value of the image representing the reflectance of the projection plane is (Rα / R _A03 , Gβ / G _A03 , Bγ / B _A03 ) _i . An image created by quantizing the ratio of these two images is an image obtained by correcting the input image. This image is projected from the imaging device 1.

  The input image correction process will be specifically described with reference to FIG. FIG. 12A is a diagram illustrating an image obtained by multiplying the input image (see FIG. 6A) by the luminance value decrease magnification distribution (see FIG. 10C). FIG. 12B shows an image obtained by dividing the image of FIG. 12A by an image representing the reflectance of the projection plane (see FIG. 6B). This image is projected from the imaging device 1. FIG. 12C is an observation image observed by the user when the image of FIG. 12B is projected onto the projection plane of FIG. In the observed image of FIG. 12C, the dynamic range of the image is wide, and the pattern and color of the projection surface are not conspicuous.

  For reference, an observation image when the input image is projected without correction is shown in FIG. FIG. 13A is a diagram showing an input image, and the input image is an image of a mountain peak taken against the background of “sky”. FIG. 13B is an image of the projection plane. FIG. 13C is an observation image observed by the user when the image in FIG. 13A is projected onto the projection plane in FIG. In the observation image 13 (c), the pattern on the projection surface can be seen well in the “sky” region of the projected image.

  Next, referring to FIG. 14 and FIG. 15, the observation image observed on the projection surface when the corrected input image is projected onto the projection surface, and the size of the kernel when smoothing the uncorrectable distribution Explain the relationship. FIG. 14A is an observation image when smoothing is not performed (when the kernel size is zero). FIG. 14B is an observation image when the kernel size is 3 × 3, and FIG. 14C is an observation image when the kernel size is 5 × 5. FIG. 15A is an observation image when the kernel size is 9 × 9, and FIG. 15B is an observation image when the kernel size is 13 × 13. FIG. 15C is an observation image when the kernel size is 25 × 25.

  As shown in FIG. 14A, if the uncorrectable distribution is not smoothed, the dynamic range of the observation image becomes very narrow, and the visibility of the observation image becomes very poor. As shown in FIGS. 14 (b), 14 (c), 15 (a), and 15 (b), as the size of the kernel when smoothing the uncorrectable distribution increases, The dynamic range is widened and the visibility of the observed image is improved. However, as shown in FIG. 15C, when the size of the kernel becomes too large, the pattern on the projection surface becomes slightly conspicuous.

According to the embodiment described above, the following operational effects can be obtained.
(1) The reflectance distribution of the projection surface is detected, the input image is input, the detected reflectance distribution is corrected based on the input image, the corrected reflectance distribution is smoothed, and the smoothed reflectance The input image is corrected based on the distribution, and the corrected input image is projected onto the projection plane. Thereby, it is possible to correct the input image with respect to the color and pattern of the projection surface without significantly reducing the visibility of the projected image.

(2) Since the input image is further corrected based on the detected reflectance distribution, the input image can be appropriately corrected for the color and pattern of the projection plane.

(3) The reflectance distribution corrected by the reflectance distribution correcting means is smoothed, the low reflectance region is expanded in the smoothed reflectance distribution, and the low reflectance region is expanded. Is further smoothed to smooth the reflectance distribution. Thereby, the smoothed reflectance distribution used when correcting the input image can be appropriately calculated.

(4) The low reflectance region is expanded in the process of smoothing the reflectance distribution to classify the smoothed reflectance distribution, and the low reflectance among the reflectance distributions in the classified region is classified. By setting the reflectivity of the region, the low reflectivity region in the smoothed reflectivity distribution was expanded. Thereby, the area | region with a low reflectance can be expanded in the smoothed reflectance distribution so that an input image can be correct | amended appropriately.

(5) A local region used for weighted average calculation in smoothing of the smoothed reflectance distribution that has been blocked (second smoothing) is used for weighted average calculation in smoothing of the smoothed reflectance distribution (first smoothing). It was made larger than the local area used. Thereby, when the input image is corrected and the dynamic range of the input image is partially narrowed, the portion can be made inconspicuous.

(6) Since the non-correctable distribution is calculated by comparing the normalized pixel value of the input image with the normalized reflectance of the projection plane, the visibility of the projected image from the projection plane is calculated. Therefore, it is possible to appropriately extract a portion with low reflectivity that is difficult to correct so as not to deteriorate. In addition, by comparing the normalized pixel value of the input image with the normalized pixel value of the image representing the reflectance of the projection plane, the normalized pixel value of the input image and the projection plane are normalized. Since the comparison with the reflectance is made, the comparison between the two can be easily performed.

The above embodiment can be modified as follows.
(1) Although the reflectance distribution of the projection plane is detected by calculating an image representing the reflectance distribution of the projection plane, the present invention is not limited to the embodiment as long as the reflectance distribution of the projection plane can be detected. For example, the reflectance distribution may be detected based on the intensity of light projected from the projection unit 110 and the intensity of reflected light on the projection surface detected by the imaging unit 120.

(2) The smoothing of the reflectance distribution on the projection surface is not limited to the embodiment unless the dynamic range of the image projected on the projection surface becomes very narrow. For example, a low-pass filter may be applied to smooth the reflectance distribution on the projection surface, and the subsequent blocking process or the second smoothing process may not be performed.

(3) In the method of expanding the low reflectance region in the smoothed reflectance distribution, if the low reflectance region can be expanded so that the input image can be corrected appropriately, the smoothed uncorrectable distribution It is not limited to blocking. Also, if the input image can be corrected appropriately, the reflectance of the region to be expanded in the smoothed reflectance distribution is not limited to the embodiment.

(4) When normalizing the pixel value of the input image, normalization may be performed by dividing the pixel value of each pixel by the maximum value of the pixel value of the input image.

(5) A comparison between the normalized pixel value of the input image and the normalized reflectance of the projection surface, and the normalized pixel value of the image representing the normalized pixel value of the input image and the reflectance of the projection surface Although the comparison is made by comparing the values, the normalized pixel value of the input image may be compared with the normalized reflectance of the detected projection surface.

(6) Although the input image is corrected based on the detected reflectance distribution and the smoothed reflectance distribution, the corrected reflectance distribution based on the input image, and the smoothed reflectance distribution The input image may be corrected based on the above. In this case, the low-luminance portion of the input image is not corrected much, but the color and pattern of the projection surface in the low-luminance portion of the input image are not noticeable, so there is no problem in the visibility of the projected image. Alternatively, the input image may be corrected with the smoothed reflectance distribution, and the corrected input image may be corrected by a conventional correction method that suppresses the influence of the pattern on the projection surface. Furthermore, the correction value for each pixel of the conventional correction method that suppresses the influence of the pattern on the projection surface is weighted based on the smoothed reflectance distribution, and the input image is corrected with the weighted correction value. You may make it do.

(7) The present invention can also be applied to the case where the input image is corrected so as to suppress the influence of ambient light irradiated on the projection surface. An outline of an application example in this case will be described with reference to a flowchart of FIG. The process in FIG. 16 is executed in the image processing unit 101A by a program that starts when the projection apparatus 1 starts a process for starting projection. Steps similar to those in the process of FIG. 3 are denoted by the same reference numerals, and differences from the process of FIG. 3 will be mainly described.

In step S1A, the projection plane onto which the black image ((R, G, B) _i = (0, 0, 0) _i ) is projected is photographed, and the brightness distribution of the ambient light on the projection plane is detected. After step S2, the process proceeds to step S3A. In step S3A, a brightness distribution that is difficult to reduce the influence of the correction of the input image in the brightness distribution of the ambient light is calculated compared to the input image. To do. Hereinafter, this calculated brightness distribution is referred to as an uncorrectable distribution. For example, when the pixel value of the input image is equal to or greater than a predetermined value of the pixel value of the image obtained by photographing the projection surface on which the black image is projected, the uncorrectable distribution value is set to zero. In addition, when the pixel value of the input image is not equal to or larger than a predetermined value of the pixel value of the image obtained by photographing the projection surface on which the black image is projected, the correction impossible distribution value is set as the pixel value of the image obtained by photographing the projection surface on which the black image is projected. And This is because the high luminance portion of the input image is less affected by ambient light, and the lower luminance portion is more affected by ambient light.

  In step S4A, the uncorrectable distribution is smoothed as in step S4 of FIG. In step S5A, the input image is corrected based on the smoothed uncorrectable distribution and the brightness distribution of the ambient light. For example, after correcting the input image according to the smoothed non-correctable distribution, the input image is corrected according to the brightness distribution of the ambient light. In the first correction, the luminance of the input image corresponding to the bright portion in the smoothed non-correctable distribution is increased, and the luminance of the input image corresponding to the dark portion in the smoothed non-correctable distribution is decreased. In the second correction, the brightness value of the input image corresponding to the dark portion in the brightness distribution of the ambient light is increased, and the brightness of the input image corresponding to the bright portion in the brightness distribution of the ambient light is decreased. . Then, the process proceeds to step S6.

  It is also possible to combine one or a plurality of embodiments and modifications. It is possible to combine the modified examples in any way.

  The above description is merely an example, and the present invention is not limited to the configuration of the above embodiment.

1 is an external view of a projection apparatus according to an embodiment of the present invention. It is a block diagram explaining the structure of the projection apparatus in embodiment of this invention. It is a flowchart for demonstrating the image process performed by an image process part. It is a flowchart for demonstrating the calculation process of the image showing the reflectance of a projection surface. It is a flowchart for demonstrating the calculation process of an uncorrectable distribution. It is a figure for demonstrating the calculation process of an uncorrectable distribution. It is a flowchart for demonstrating an uncorrectable distribution smoothing process. It is a figure for demonstrating smoothing of uncorrectable distribution. It is a figure for demonstrating the smoothing of the block of uncorrectable distribution. It is a figure for demonstrating an uncorrectable distribution smoothing process. It is a flowchart for demonstrating the correction process of an input image. It is a figure for demonstrating the correction process of an input image. It is a figure for demonstrating the observation image at the time of projecting without correcting an input image. It is a figure for demonstrating the observation image at the time of changing the magnitude | size of a kernel. It is a figure for demonstrating the observation image at the time of changing the magnitude | size of a kernel. It is a flowchart for demonstrating the image process in the case of correct | amending an input image so that the influence of the ambient light irradiated to the projection surface may be suppressed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Projection apparatus 101 Control circuit 101A Image processing part 104 External interface 105 Memory card interface 110 Projection unit 111A Projection lens 120 Imaging unit 121A Imaging lens

Claims (3)

A reflectance distribution detecting means for detecting the reflectance distribution of the projection surface by capturing the projected black image and white image ;
An image input means for inputting an input image;
Correction impossible distribution calculation for calculating a correction impossible distribution by comparing the corresponding normalized pixel values of said detected reflectance distribution of normalized pixel value and the input image by the reflectance distribution detecting means Means,
A reflectance distribution smoothing means for smoothing the correction impossible distribution calculated by said correction impossible distribution calculating means with a predetermined size of the kernel region,
Input image correction means for correcting the input image based on the non-smooth correction distribution smoothed by the reflectance distribution smoothing means;
A projection device comprising: a projection unit that projects the input image corrected by the input image correction unit onto the projection plane. The projection device according to claim 1,
The reflectance distribution smoothing means is smoothed by the first reflectance distribution smoothing means for smoothing the non- correctable distribution calculated by the non-correctable distribution calculating means , and the first reflectance distribution smoothing means. In the smoothed reflectance distribution, the smoothed non-correctable distribution is blocked and the lower reflectance in the reflectance distribution in the blocked area is used as the reflectance of the blocked area. A projection apparatus comprising: a second reflectance distribution smoothing unit that expands a region having low reflectance, smoothes the expanded reflectance distribution, and calculates a luminance value reduction magnification distribution . The projection apparatus according to claim 2, wherein
The first reflectance distribution smoothing means and the second reflectance distribution smoothing means smooth the reflectance distribution by weighted average calculation and are used for weighted average calculation in the second reflectance distribution smoothing means. kernel space for a projection apparatus characterized by greater than the kernel area used for weighted mean calculation in the first reflectance distribution smoothing means.

Images