JP2961776B2 - Video signal processing circuit - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video signal processing circuit for providing a special video effect.

[Summary of the Invention]

The present invention compares a luminance signal level in an input video signal with a gradually changing level in a video signal processing circuit which is preferably applied particularly to a video camera which performs signal processing by a digital circuit, and responds to the comparison output. A special video effect is provided by switching and outputting a video signal and a signal of a predetermined level.

The present invention compares a chroma signal level in an input video signal with a gradually changing level in a video signal processing circuit which is preferably applied particularly to a video camera in which signal processing is performed by a digital circuit. A special video effect is provided by switching and outputting a video signal and a signal of a predetermined level.

The present invention particularly relates to a video signal processing circuit suitable for application to a video camera in which signal processing is performed by a digital circuit, in which a composite video signal is compared with a gradually changing level. A special video effect is provided by switching and outputting the level signal.

[Conventional technology]

In recent years, it has been considered to add various functions in order to increase the functions and performance of video cameras. As a newly added function, there is no need to add large-scale hardware, and it is desired that the function can be differentiated from other models and contribute to the enhancement of commercial value. It is important to develop functions for providing special video effects in order to differentiate from other models and improve product value.

[Problems to be solved by the invention]

As described above, it is desired to add a new function without providing a large-scale hardware in order to increase the functions and performance of the video camera.

Therefore, an object of the present invention is to provide a video signal processing circuit which can realize a function for providing a special video effect without adding large-scale hardware.

[Means for solving the problem]

The present invention provides a special video effect by comparing a luminance signal level in a video signal with a gradually changing level, and switching and outputting a video signal and a signal of a predetermined level according to the comparison output. This is a video signal processing circuit.

The present invention provides a special video effect by comparing a chroma signal level in a video signal with a gradually changing level, and switching and outputting a video signal and a signal of a predetermined level according to the comparison output. This is a video signal processing circuit.

The present invention compares a composite video signal with a gradually changing level, and switches and outputs a video signal and a signal of a predetermined level according to a comparison output.
This is a video signal processing circuit with a special video effect.

[Action]

By comparing the luminance signal level in the input video signal with a gradually changing level, and switching and outputting the video signal and a signal of a predetermined level in accordance with the comparison output, the entire screen is changed from a single color screen state. The image appears from the part with the higher luminance level, and then the whole screen appears.The image effect like fade-in, or the image from the normal screen fades out from the part with the lower luminance level. Such a video effect can be provided.

Also, by comparing the chroma signal level in the input video signal with a gradually changing level, and switching and outputting the video signal and a signal of a predetermined level according to the comparison output, the entire screen is in a single color state. Therefore, it is possible to provide an image effect such that a screen gradually appears from a portion having a high color saturation, and an image effect such that the image gradually disappears from a portion having a low color saturation from a normal screen.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 2 is an example of a video camera to which the present invention can be applied. In FIG. 2, reference numeral 1 denotes a lens, and 2 denotes a CCD image sensor. A subject image that has passed through the lens 1 is formed on the light receiving surface of the CCD image sensor 2.

The position of the lens 1 can be moved by a focus drive motor 3. An iris ring is provided in the lens 1, and the opening and closing of the iris ring is controlled by an iris drive motor 4. The iris opening is detected by the iris position detection circuit 5. The zoom position is detected by the zoom position detector 6.

The output of the CCD image sensor 2 is a sample and hold circuit 7, an AGC
The signal is supplied to an A / D converter 9 via a circuit 8. An image signal obtained from the CCD image sensor 2 is digitized by the A / D converter 9.

The output of the A / D converter 9 is supplied to a digital video signal processing circuit 10 and also to an optical detector circuit 11.

The optical detector circuit 11 includes an AF detection circuit 12 for obtaining an AF detection signal for auto focus control, an AE detection circuit 13 for obtaining an AE detection signal for automatic exposure control, and an AWF detection signal for auto white balance. And an AWF detection circuit 14.

The optical detector circuit 11 and the controller 15 are bidirectionally connected. Optical detector circuit
From 11 to controller 15, AF detection signal, AE detection signal, AW
The B detection signal is supplied.

From this optical detector circuit 11 to the controller
15 based on the AF detection signal sent to
A lens drive signal is output from 15. This lens drive signal is supplied to the focus drive motor 3 via the driver 16. Thus, the position of the lens 1 is controlled so as to be at the in-focus position.

Also, based on the AE detection signal sent from the optical detector circuit 11 to the controller 15, an iris control signal is output from the controller 15 and the AGC
A control signal is output. The iris control signal from the controller 15 is supplied to the iris drive motor 4 via the driver 17. Further, an AGC control signal from the controller 15 is supplied to the AGC circuit 8 via the D / A converter 18. Thus, the iris ring is opened and closed according to the image signal level, and the gain of the AGC circuit 8 is set.

The digital video signal processing circuit 10 includes the CCD image sensor 2
For example, a composite video signal of the NTSC system is formed from the image pickup signal from the camera. The digital video signal processing circuit 10 outputs a digital composite video signal. This digital composite video signal
The signal is converted to an analog signal by the D / A converter 19, and output terminal 2
Output from 0.

FIG. 1 shows a first embodiment of the present invention. An embodiment of the present invention is provided in a digital video signal processing circuit 10 of a video camera configured as described above.

In FIG. 1, a digital luminance signal Y is input to an input terminal 31.
Are supplied, and digital chroma signals (RY) and (BY) are supplied to the input terminals 32 and 33. The digital luminance signal Y and the digital chroma signals (RY) and (BY) are supplied to the digital color encoder circuit 34. In the digital color encoder circuit 34, a digital composite color video signal V is formed from the digital luminance signal Y and the digital chroma signals (RY) and (BY). The digital composite color video signal V is supplied to the a-side input terminal of the selector 35.

_A signal _VA at a predetermined level is supplied from an input terminal 39 to the b-side input terminal of the selector 38.

Further, the digital luminance signal Y from the input terminal 31 is supplied to one input terminal of the digital comparator 40. The other input terminal of the digital comparator 40 has a counter
The reference luminance signal _Yref is supplied from 41. The digital comparator 40 compares the level of the digital luminance signal Y from the input terminal 31 with the level of the reference luminance signal _Yref .

The counter 41 is supplied with a clock from an input terminal 42 and an up / down signal from an input terminal 43. The counter 41 counts up or down the clock from the input terminal 42. As a result, a reference luminance signal _Yref that changes with time is formed.

The output of the digital comparator 40 is the select signal SEL.
Is supplied to the selector 35. This select signal SEL
Thus, the selector 35 is switched. The output of the selector 35 is output from the output terminal 36.

When the counter 41 outputs a reference luminance signal _Yref that changes with time, special video effects such as fade-in and fade-out can be provided.

For example, when the reference luminance signal _Yref is gradually lowered from a large level, for example, an image appears from a high luminance level portion from a black screen state, and then,
As if the entire screen appears, the image effect is like a fade-in.

That is, as shown in FIG. 3A, it is assumed that the reference luminance signal _Yref is gradually decreased with time. In this case, first, the reference luminance signal _Yref is changed to the luminance signal Y.
3B, the selector 35 continues to be set to the b side as shown in FIG. 3B. Therefore, as shown in FIG. 3C, the signal of the predetermined level V _A (for example, the black level) is continuously output. For this reason, the entire screen is all black.

When the reference luminance signal Y _ref gradually decreases with time, the luminance signal Y becomes larger than the reference luminance signal Y _{ref in a} portion where the luminance signal Y has a high level.
Accordingly, as shown in FIG. 3B, the selector 35 can be switched to the a side at the portion where the level of the luminance signal Y is high. Accordingly, as shown in FIG. 3C, the composite video signal V
Is output, and a predetermined level _VA is output in a portion where the level of the luminance signal Y is low. For this reason, the entire screen is changed from, for example, a black single color state to a state in which only a bright portion appears on the screen.

When the reference luminance signal _Yref further drops, the level of the luminance signal Y is changed to the reference luminance signal Y in any part.
larger than _ref . Therefore, as shown in FIG. 3B, the selector 35 continues to be set to the a side. Therefore,
As shown in FIG. 3C, the composite video signal V is continuously output. Therefore, a normal screen is displayed.

If the reference luminance signal _Yref is gradually increased from a small level, an image effect such as fade-out appears as if an image disappears from a low luminance portion from a normal screen.

In the above-described embodiment, the signal level of the luminance signal Y is compared with the reference luminance signal _Yref that changes with time, and the selector 35 is controlled by the comparison output. However, the signal level of the composite video signal V is controlled. May be compared with a reference video signal that changes with time, and the selector 35 may be controlled by this comparison output.

FIG. 4 shows another embodiment of the present invention.
In this embodiment, the chroma signals (RY) and (BY) from the input terminals 32 and 33 are supplied to digital comparators 51 and 52 via absolute value circuits 45 and 46, and the chroma signals (RY) ) and (the level of the reference chroma signal C _ref from the level and the counter 41 of the B-Y) are compared. This comparison output is supplied to the selector 35 via the OR gate 54.

When the counter 41 outputs the reference chroma signal _Cref that changes with time, a special video effect can be provided.

For example, by gradually lowering the reference chroma signal _Cref from a large level, it is possible to provide a video effect in which the entire screen is gradually changed from a single color state to a screen gradually appearing from a portion having a high color saturation. For example, when the reference chroma signal _Cref is gradually increased from a small level, it is possible to provide an image effect such that the screen gradually disappears from a portion having a low color saturation from a normal screen.

〔The invention's effect〕

According to the present invention, the luminance signal level in the input video signal is compared with the gradually changing level, and the video signal and the signal of the predetermined level are switched and output according to the comparison output, so that the whole is monochromatic. From the state of the screen, the video effect appears from the part with the higher luminance level and then the entire screen appears, or the image effect that the image disappears from the part with the lower luminance level from the normal screen. Can be given.

Also, by comparing the chroma signal level in the input video signal with a gradually changing level, and switching and outputting the video signal and a signal of a predetermined level according to the comparison output, the entire screen is in a single color state. Therefore, it is possible to provide a video effect such that a screen gradually appears from a portion having a high color saturation, and a video effect such that a screen gradually disappears from a portion having a low color saturation from a normal screen.

In the video camera to which the present invention can be applied, the output of the CCD image pickup device is digitized by the A / D converter 9, digital signal processing is performed by the digital video signal processing circuit 10, and optical control is performed by digital processing. Will be

In the case of digital signal processing, a gradually changing reference level can be easily formed by the counter 41. For this reason, a special video effect can be provided without adding complicated hardware.

[Brief description of the drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a block diagram showing an overall configuration of a video camera to which the present invention can be applied, FIG. 3 is a waveform diagram used for describing one embodiment of the present invention, FIG. 4 is a block diagram of another embodiment of the present invention. Explanation of main symbols in the drawings 34: digital color encoder, 35: selector, 40, 52, 52: comparator, 41: counter.

Continued on the front page (72) Inventor Fumiaki Kato 6-7-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Inside Sony Corporation (72) Inventor Katsuaki Hirota 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Stock In-company (56) References JP-A-3-34783 (JP, A) JP-A-63-211881 (JP, A) US Patent 4,605,967 (US, A) US Patent 4,262,249 (US, A) European Publication 162499 (EP , A1) (58) Field surveyed (Int. Cl. ⁶ , DB name) H04N 5/262-5/28

Claims (2)

(57) [Claims] An encoding means for forming a composite color video signal from a component color signal comprising a luminance signal and a chroma signal; a gradient level generating means for generating a gradient level whose level gradually changes with time; The level of the luminance signal input to the encoding means,
Comparing means for comparing a gradient level generated from the gradient level generating means with a selecting means for switching between a composite color video signal output from the encoding means and a constant level signal by an output of the comparing means; Comparing the luminance signal level input to the encoding means with the tilt level by the comparing means, and switching and outputting the composite color video signal and the constant level signal according to the comparison output. A video signal processing circuit that provides a special video effect such that an image appears from a high-luminance part or disappears from a low-luminance part. 2. An encoding means for forming a composite color video signal from a component color signal comprising a luminance signal and a chroma signal; a gradient level generating means for generating a gradient level whose level gradually changes with time; Comparing means for comparing the level of the chroma signal input to the encoding means with the gradient level generated from the gradient level generating means; and the chroma signal level and the gradient level input to the encoding means by the comparing means. By switching between the composite color video signal and the predetermined level according to the comparison output and outputting the same, an image appears from a portion having a high color saturation or an image appears from a portion having a low color saturation. A video signal processing circuit that has a special video effect that disappears.