JPH03166867A - Field motion blur preventive camera - Google Patents

Abstract

PURPOSE:To obtain a motion blur preventive camera without deterioration in picture quality due to fluctuation in the lightness by correcting the distribution of the lightness with picture segmentation position information from a field motion detection means and with lightness distribution information of a lens from a correction function generating means. CONSTITUTION:A field motion detection means 4 detects time movement quantity of an image focused to an image pickup means 2 electrically, or an angle fitted to a camera, or information from an angular velocity sensor and field motion from a lens magnification equivalently. A field motion segmentation means 3 controls the picture segmentation position from the means 2 depending on the quantity of field motion to eliminate the effect of the field motion. A correction function generating means 5 outputs how the lightness of image focused onto the means 2 is fluctuated depending on location based on the design data of the lens according to the difference of the lightness between the center and the surrounding part of the lens 1. A lens lightness correction means 6 corrects the lightness of the pattern in response to the lightness data based on the segmentation location information from the means 4 and the location from the means 5.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an image stabilization camera that corrects image quality deterioration caused by the brightness distribution of a lens, which is noticeable when preventing image stabilization. BACKGROUND OF THE INVENTION FIG. 3 is a block diagram of an example of a conventional image stabilization camera. 1 is a lens, 2 is an imaging means, 3 is an image cutting means, and 4 is an image blur detection means. An image of the subject is formed on the imaging means 2 by the lens l. Image blur detection means 4
is electrically the amount of time movement of the image focused on the imaging means 2,
Alternatively, the amount of image shake is equivalently detected from information from the angle or angular velocity sensor attached to the camera and the magnification of the lens. The image cropping means 3 obtains a video signal without image shake by controlling the image cropping position from the imaging means according to the detected amount of image shake (for example, t screen shake correction device 1 TV Society Technology). Report V
ol1 1, Na3. pp43-48, May 1987 issue). Problem to be Solved by the Invention However, in the above example, since the brightness of the lens is different between the center and the periphery, the camera output becomes brighter or darker depending on the image cutting position in response to image blur. The screen looked restless. Another drawback is that when cropping near the edges, the brightness varies greatly between the left and right sides or the top and bottom of the screen.

Means to solve the problem i! l! In order to solve the problem, the present invention includes a lens, an imaging means for receiving an image of a subject by the lens and outputting an imaging signal, and detecting the amount of image blur of the imaging signal and outputting image cutting position information. An image blur detection means, an image cutting means for cutting out an image from an image signal based on the cutting position information, a correction function generating means for outputting brightness distribution information depending on the location of the lens, and an output of the correction function generating means and the cutting position. The apparatus is configured to include a lens brightness correction means for correcting the lens brightness variation component from the output of the image cutting means based on the information and outputting a video signal. According to the present invention, with the above-described configuration, it is possible to obtain a video signal with little variation in brightness regardless of how the screen is cut out, and it is possible to provide an image stabilization camera without image quality deterioration.

EXAMPLE Hereinafter, a west shake prevention camera according to an example of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the image stabilization camera of the present invention. 1 is a lens, 2 is an imaging means, 3 is an image cutting means, 4 is an image blur detection means, 5 is a correction function generation means, and 6 is a lens brightness correction means. First, an image of a subject is formed by a lens l onto an imaging means 2 composed of a COD, a MOS, an image pickup tube, and the like. Image blur detection means 4
is electrically the amount of time movement of the image focused on the imaging means 2,
Alternatively, the amount of image shake is equivalently detected from information from the angle or angular velocity sensor attached to the camera and the magnification of the lens. The influence of image blur is removed by controlling the image cutting position from the imaging means by the image cutting means 3 according to the detected amount of image blur. The correction function generation step 5 calculates how much the brightness of the image formed on the imaging means 2 varies depending on the location due to the difference in brightness between the center and peripheral parts of the lens l, based on the design data of the lens. Output. The lens brightness correction 1,000 steps 6 uses the cropping position information from the image blur detection means 4 and the correction function generation means 5
The brightness of the screen is corrected according to the brightness data depending on the location. The video signal whose brightness has been corrected in this way can be recorded on a tape, or as a still camera on a floppy disk or an IC card. The lens brightness correction means 6 can be composed of a multiplier or the like. The image cutting means 3 can be easily realized not only by controlling the readout of one screen's worth of memory but also by controlling the readout timing of the signal from the imaging means 2.

Further, the correction function generating means 5 may record the brightness correction amount corresponding to the location in the ROM, or simply calculate it as a function of the location, for example, a function of the distance from the center of the lens, according to an approximation formula. In addition, since the TV screen is horizontally long with an aspect ratio of 4:3 for NTSC specifications and 16:9 for HD specifications, variations in brightness are more noticeable in the horizontal direction, so when only correcting the brightness in the horizontal direction of the lens But you can get great results. At this time, it greatly contributes to the reduction of hardware requirements, such as by simplifying control. FIG. 2 shows an embodiment in which the present invention is applied to a camera using a zoom lens, where 1a is a zoom lens, 7 is a zoom encoder, and 8 is an aperture detection means. The other configurations are the same as those shown in FIG. 1, so their explanation will be omitted. In the case of a zoom lens, the brightness distribution of the lens may differ depending on the zoom ratio. In this case, by detecting the zoom ratio with the zoom encoder 7 and controlling the output of the correction function generating means 5, the brightness can be appropriately corrected in any case. Additionally, the brightness distribution of the lens may differ depending on the aperture amount. At this time, as shown in this embodiment, the aperture amount may be detected by the aperture detection means 8, and the output of the correction function generating stage 5 may be controlled based on the output thereof. The zoom encoder 7 can be used in common when the image blur detection means 4 is of a type that equivalently detects the amount of image blur from information from an angle or angular velocity sensor attached to the camera and the magnification of the lens.

Effects of the Invention As described above, according to the present invention, since the correction function generation means and the lens brightness correction means are provided, the image cutting position information from the image blur detection means and the lens brightness from the correction function generation means are provided. Since the brightness distribution information at each location on the screen at that time can be accurately corrected using the brightness distribution information, it is possible to provide an image stabilization camera that does not cause image quality deterioration due to brightness fluctuations.

[Brief explanation of the drawing]

Figure 1 is a block diagram of the image stabilization camera of the present invention, Figure 2
The figure is a block diagram showing another embodiment of the present invention, and FIG. 3 is a block diagram of a conventional image stabilization camera. 1...lens, 2...imaging means, 3.
... Image cutting means, 4 ... Image blur detection means, 5 ... Correction function generation means, 6 ...
... Lens brightness correction means, 7 ... Zoom encoder, 8 ... Aperture detection means.

Claims (5)

[Claims] (1) a lens, an imaging means for receiving an image of a subject by the lens and outputting an imaging signal, and an image blur detection means for detecting an amount of image blur in the imaging signal and outputting image cropping position information; an image cutting means for cutting out an image from the imaging signal based on the cutting position information; a correction function generating means for outputting brightness distribution information depending on the location of the lens; and an output of the correction function generating means and the cutting position information. 1. A camera for preventing image blur, comprising: a lens brightness correcting means for correcting a brightness fluctuation component of the lens from the output of the image cutting means based on the above, and outputting a video signal. (2) An aperture detection means for detecting the amount of aperture of the lens is provided, and the correction function generation means outputs brightness distribution information depending on the location of the lens based on the output of the aperture detection means. (1) Image stabilization camera as described. (3) The lens is a zoom lens with variable magnification, and includes a zoom encoder that detects the zoom ratio of the zoom lens, and the correction function generating means is configured to distribute brightness depending on the location of the zoom lens based on the output of the zoom encoder. The image stabilization camera according to claim 1, wherein the camera outputs information. (4) The lens is a zoom lens with variable magnification, and a zoom encoder detects the zoom ratio of the zoom lens;
comprising an aperture detection means for detecting an aperture amount of the zoom lens, and a correction function generation means outputting brightness distribution information depending on the location of the zoom lens based on the output of the zoom encoder and the output of the aperture detection means. The image stabilization camera according to claim (1), characterized in that: (5) Any one of claims (1) to (4), wherein the lens brightness correction means corrects only the horizontal component of the brightness variation depending on the location of the lens and outputs the video signal. Image stabilization camera described in .