JP2009130496A - Waveform display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that an image is difficult to be confirmed in a state in which display of a histogram of brightness signals is not required when the histogram is always displayed over the image independently of photographic situations. <P>SOLUTION: A waveform display device includes: an external input I/F 101 for inputting a video signal from the outside; a waveform generator 103 for generating a waveform signal from the video signal; an external light sensor 107 for detecting ambient brightness; and a switch 104 for superposing the waveform signal on the video signal to output them when the detection result of the external light sensor 107 is a prescribed value or higher, and for outputting only the video signal in the other cases. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a waveform display device for inputting an image from a camera and checking the state of exposure and color.

  The conventional waveform display device calculates the luminance level distribution of the imaged video signal by calculation so as to make it easy to check the exposure and color settings of the camera being imaged, and superimposes it on the imaged video. Are displayed on the viewfinder (see, for example, Patent Document 1).

FIG. 4 is a block diagram showing a configuration of a conventional waveform display device. FIG. 5 is an explanatory view of display when a waveform signal is superimposed on a video signal in a conventional waveform display device. In FIG. 4, the output from the image sensor 201 is analog signal processed by the analog signal processing circuit 202, digitally converted by the A / D converter 203, and then supplied to the digital signal processing circuit 204. The luminance signal and the color difference signal separated and output by the digital signal processing circuit 204 are temporarily stored in the frame memory 205 and recorded in the semiconductor memory 206 in units of frames. On the other hand, the luminance signal output output from the digital signal processing circuit 204 is supplied to the frequency distribution calculation circuit 207, and the frequency distribution of the luminance level in one frame section is calculated. The calculation result is supplied to the display signal forming circuit 208, and a display signal for displaying a histogram is generated. The superimposing circuit 209 is supplied with the luminance signal from the digital signal processing circuit 204 and the display signal from the display signal forming circuit 208, and both signals are superimposed on the view through the D / A converter 210. The image is displayed on the viewfinder 211, and the image and the histogram are superimposed and displayed as shown in FIG.
Japanese Unexamined Patent Publication No. 7-38801

  However, in the conventional configuration, since the histogram of the luminance signal is always superimposed on the image on the viewfinder regardless of the shooting situation, only the image on the viewfinder such as indoor shooting is necessary, for example, when the histogram display is unnecessary. In the case where the shooting conditions can be determined by, the movement of the histogram is obstructed, making it difficult to check the video. Even if it is possible to switch the presence / absence of superimposed display by menu operation or button operation, if the operation is inadvertently performed during shooting, the angle of view itself may move and cause shooting failure. Was.

  In view of the above problems, the waveform display device of the present invention aims to provide a waveform display device capable of appropriately displaying a histogram or the like.

  In order to solve the above-described conventional problems, a waveform display device of the present invention includes a video input unit that inputs a video signal from the outside, a waveform video signal generation unit that generates a waveform video signal based on the video signal, Brightness detection means for detecting brightness, switching means for outputting one of a superimposed signal and a video signal on which a video signal and a waveform video signal are superimposed as a display video signal, and a detection result of the brightness detection means When it is equal to or greater than a predetermined threshold value, the switching means is controlled to output a superimposed signal, and when the detection result of the brightness detection means is less than the predetermined threshold value, a video signal is output. Control means for controlling the switching means, and display means for displaying the video signal for display.

  According to the waveform display device of the present invention, when it is determined that it is difficult to check the settings of the camera exposure, color, etc. by only the image on the video monitor, such as outdoor shooting during the daytime, the waveform signal is automatically generated. Is superimposed and displayed, the camera settings can be confirmed quantitatively, and shooting failures due to overexposure, white balance deviation, and the like can be prevented. In addition, since the waveform signal is not superimposed under a situation where the setting can be confirmed only on the video monitor such as indoor shooting, confusion due to unnecessary information can be prevented.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

(Embodiment 1)
FIG. 1 is a block diagram showing a configuration of a waveform display device according to Embodiment 1 of the present invention. FIG. 2 is an explanatory diagram of a display operation when a waveform signal is superimposed on a video signal in the waveform display device according to Embodiment 1 of the present invention.

  In FIG. 1, an external input I / F 101 receives digital video signal data sent from an external video camera in a form suitable for transmission. The signal processor 102 separates the luminance signal and the color difference signal from the digital video signal data output from the external input I / F 102.

  The waveform generator 103 generates a video signal having a waveform of one frame period from the luminance signal output from the signal processor 102 (the vertical axis represents the luminance level and the horizontal axis represents the horizontal pixel position of the video signal). Specifically, a waveform signal to be displayed is first generated from the luminance signal. The waveform signal includes the luminance level of a predetermined horizontal line for each pixel position in the horizontal direction (or for each predetermined range in the horizontal direction), and the average luminance in the vertical direction for each horizontal pixel position (or for each predetermined range in the horizontal direction) Level, etc. Next, the waveform generator 103 draws this waveform signal as a graph, that is, converts it into a luminance signal and a color difference signal that become a waveform video signal, and outputs them. The waveform generator 103 generates a vector waveform signal (RY on the vertical axis and BY on the horizontal axis) for one frame period from the color difference signal instead of such a waveform signal, and this is generated as a video signal. It is also possible to output after converting to. The frequency of each luminance level in the luminance signal of one frame may be output as a histogram. The type of waveform signal to be generated is switched by control from the controller 108 (described later).

  The switch 104 superimposes and outputs the luminance signal and color difference signal from the signal processor 102 and the luminance signal and color difference signal from the waveform generator 103 under the control of the controller 108 or outputs only the video signal. To do. The LCD driver 105 performs RGB conversion, pixel conversion, and level conversion on the luminance signal and the color difference signal from the switch 104. The LCD monitor 106 displays a signal from the LCD driver 105.

  The external light sensor 107 is an infrared sensor attached to the surface of the housing. Infrared light (in outdoor sunlight, the sunlight itself contains a large amount of infrared light, but in indoor fluorescent lighting, it is reflected in the fluorescent light itself. Since it does not contain infrared rays, it can detect the intensity of outdoor indoors with or without infrared rays. The controller 108 instructs the waveform generator 103 on information such as an area for displaying a waveform and what kind of waveform signal is output based on preset menu setting information. Further, the controller 108 detects the ambient brightness by comparing the detection result from the external light sensor 107 with a predetermined threshold value. Instruct superimposition.

  The waveform signal superimposing operation will be described in more detail. Consider a case in which the waveform display device is connected to a camera and a picture is taken during the day while moving from indoors to outdoors with fluorescent lighting. Since it is under fluorescent lighting indoors, the detection result of the external light sensor 107 is lower than a predetermined threshold value. Therefore, the controller 108 determines that the ambient usage state is not very bright (darker than the outdoor usage state) and fixes the output of the switch 104 to the luminance signal and the color difference signal from the signal processor 102. Therefore, only the video from the camera connected to the external input I / F 101 is displayed on the LCD monitor 106. Next, in a scene where the shooting scene changes from indoor to outdoor, the infrared detection level from the external light sensor 107 becomes high from the moment when it goes outside and the threshold value is exceeded. The controller 108 determines that the ambient use state is much brighter than the output from the external light sensor 107, and causes the switch 104 to display the luminance signal and color difference signal from the signal processor 102 and the luminance signal from the waveform generator 103. And instructing to output the color difference signal superimposed. Therefore, the waveform is displayed on the LCD monitor 106 so as to overlap the image from the camera.

  As explained above, when shooting with a camera outdoors during the day, the brightness of the display part is lower than sunlight, which is external light, so check the dark part and whiteout of the external input video from the camera However, according to the waveform display device of the present invention, the controller 108 determines that the controller 108 is used under sunlight based on the detection result of the external light sensor 107, and the switch 104 To superimpose the waveform signal on the external input video. Accordingly, the state of exposure and color can be quantitatively confirmed, and shooting failure due to overexposure or white balance deviation can be prevented.

  In this embodiment, a photosensor that detects brightness is used as the external light sensor 107 instead of the infrared sensor, and a waveform signal is superimposed on the external input video when the detection level from the photosensor exceeds a certain amount. It is good also as a structure.

(Embodiment 2)
FIG. 3 is a block diagram showing the configuration of the waveform display device according to Embodiment 2 of the present invention. In FIG. 3, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. The waveform display device according to the second embodiment is different from the first embodiment in that an image sensor 109, an analog signal processing circuit 110, and an A / D converter 111 are provided instead of the external input I / F 101.

  The image sensor 109 photoelectrically converts an image formed by a lens (not shown) and supplies it to the analog signal processing circuit 110. The analog signal processing circuit 110 performs analog signal processing on the input analog video signal. The signal subjected to the analog signal processing by the analog signal processing circuit 110 is digitally converted by the A / D converter 111 and supplied to the signal processor 102. The signal flow and operation after the signal processor 102 are as described in the first embodiment.

  As described above, since the camera and the display unit are integrated, even when the shooting scene moves from indoor to outdoor during the day, the waveform is superimposed at the moment when the display becomes outdoor when the visibility of the display unit deteriorates. Since it is displayed, it is possible for the cameraman himself to confirm the shooting state without changing the posture of the camera operation.

  The waveform display device according to the present invention quantitatively confirms these settings even in situations where it is difficult to confirm the settings of the camera exposure, color, etc., using only images on a video monitor, such as outdoor daytime photography. It is possible to prevent shooting failure due to overexposure or white balance deviation, and therefore, it can be applied to a professional camera or the like that needs to reliably shoot a subject.

The block diagram which shows the structure of the waveform display apparatus in Embodiment 1 of this invention. In the waveform display apparatus in Embodiment 1 of this invention, display operation explanatory drawing when a waveform signal is superimposed on a video signal The block diagram which shows the structure of the waveform display apparatus in Embodiment 2 of this invention. Block diagram showing the configuration of a conventional waveform display device In a conventional waveform display device, display explanation diagram when waveform signal is superimposed on video signal

Explanation of symbols

101 External input I / F
DESCRIPTION OF SYMBOLS 102 Signal processor 103 Waveform generator 104 Switch 105 LCD driver 106 LCD monitor 107 Ambient light sensor 108 Controller 109 Image sensor 110 Analog signal processing circuit 111 A / D converter

Claims (4)

Video input means for inputting a video signal from the outside;
Waveform video signal generating means for generating a waveform video signal based on the video signal;
Brightness detection means for detecting ambient brightness;
Switching means for outputting either one of the video signal and the superimposed signal on which the waveform video signal is superimposed and the video signal as a display video signal;
When the detection result of the brightness detection means is equal to or greater than a predetermined threshold value, the switching means is controlled to output the superimposed signal, and the detection result of the brightness detection means is a predetermined threshold value. A control means for controlling the switching means to output the video signal,
Display means for displaying the display video signal;
A waveform display device. The waveform display apparatus according to claim 1, wherein the waveform video signal generation unit generates the waveform video signal by extracting a luminance level in the video signal. The waveform display device according to claim 1, wherein the waveform video signal generation unit generates the waveform video signal from a vector waveform signal obtained by extracting a color difference level in the video signal. Imaging means for imaging light from a subject and outputting a video signal;
Waveform video signal generating means for generating a waveform video signal based on the video signal;
Brightness detection means for detecting ambient brightness;
Switching means for outputting either one of the video signal and the superimposed signal on which the waveform video signal is superimposed and the video signal as a display video signal;
When the detection result of the brightness detection means is equal to or greater than a predetermined threshold value, the switching means is controlled to output the superimposed signal, and the detection result of the brightness detection means is a predetermined threshold value. A control means for controlling the switching means to output the video signal,
Display means for displaying the display video signal;
An imaging apparatus comprising: