JPH02278972A - digital television receiver - Google Patents

Abstract

PURPOSE:To provide special effect to a picture at changeover of channel by changing a write area of a video data into a frame memory based on a detection signal of a channel changeover detection circuit from part of the memory area to all memory areas as a time elapses. CONSTITUTION:The receiver is provided with a channel changeover detection circuit 21 and a memory controller 23 and when a channel of a tuner 1 is changed over, the channel switching detection circuit 21 detects it and the memory controller 23 changes the write area of a video data into a frame memory 9 from part of the areas fo all the areas as time elapses based on the detection signal. Thus, a display pattern of a corresponding display section 17 displays a picture of the channel before changeover as a still picture and the picture of the channel after the changeover is displayed to the part of the areas of the still picture as a moving picture. Then the display area of the moving picture reaches the entire areas of the display section while being expanded as the time elapses. Thus, the change in the picture at channel changeover is enjoyed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a digital television receiver in which a special effect is given to a switching image when switching channels.

[Prior Art] Recently, digital television receivers that apply digital technology to the signal processing system (for example, EDTV (Estende
d Definition Television) television receivers) are attracting attention. These digital television receivers have been designed to improve image quality and stabilize performance.
In addition, it has been disclosed that it has functions that were not possible with conventional analog television receivers, such as a screen freeze function and a picture-in-picture function. The images of the selected channels were displayed and changed instantly.

[Problems to be Solved by the Invention] As mentioned above, conventional digital television receivers did not have a function to change the image when changing channels. The problem was that it was not possible.

The present invention was made in view of the above-mentioned problems, and it is an object of the present invention to provide a digital television receiver that provides special effects to images when changing channels.

[Means for Solving the Problems] The present invention converts a video signal received by an antenna and selected by a tuner into digital video data by an A/D conversion circuit, writes this video data to a frame memory, In a digital television receiver in which video data read from a frame memory is converted into an analog video signal by a D/A conversion circuit and displayed on one display section, a channel switching detection circuit detects channel switching of the tuner. , and a memory controller that changes an area for writing video data into the frame memory from a part of the memory area to the entire memory area over time based on the detection output signal of the channel switching detection circuit. It is characterized by this.

[Function] When a predetermined channel is selected by the tuner, the video data for one frame of the selected channel is sequentially written to all memory areas of the frame memory and sequentially read out, and displayed on the display section. The video of the selected channel will be displayed. Here, when the tuner channel is switched, the channel switching detection circuit detects this and outputs a detection signal. Then, based on this detection signal, the memory controller changes the write area of the video data into the frame memory from a part of the area to the entire area over time. Therefore, the display screen of the corresponding display section displays the image of the channel before switching as a still image, and displays the image of the channel after switching as a moving image in a part of the still image. The display area of this moving image expands over the course of one hour and reaches the entire area of one display section.

[Embodiment] FIG. 1 shows an embodiment of a digital television receiver according to the present invention. In this figure, reference numeral 1 denotes a tuner that selects a predetermined color television signal from among a plurality of color television signals received by an antenna 3. The output side of this tuner 1 is coupled with an A/D (analog/digital) conversion circuit 5 that converts a selected TV signal into digital video data, and the output side of this A/D conversion circuit 5 is connected to a luminance signal. The video signal is connected to a frame memory 9 that stores video data for one frame through a video signal processing circuit 7 that includes a Y/C separation circuit that separates color signals, a luminance signal processing circuit, and a color signal processing circuit. ing. On the output side of the frame memory 9, there is a double speed conversion circuit 11 for performing scanning line interpolation. Converting video data to analog video signals D
A /A (digital-to-analog) conversion circuit 13, a matrix circuit 15, and a CRT 17 serving as a display section are sequentially connected.

Reference numeral 21 denotes a channel switching detection circuit that detects channel switching in the tuner 1 and outputs a detection signal. A memory controller 23 controls reading and writing of the frame memory 9. When a predetermined channel is being received and there is no detection output signal from the channel switching detection circuit 21, the memory controller 23 sequentially writes the video data from the video signal processing circuit 7 into the frame memory 9, and The written video data is read out sequentially, and when switching channels, the video data of the channel before switching is stored in the frame memory 9 based on the detection output signal from the channel switching detection circuit 21, and the same data is repeatedly read. At the same time, the video data of the channel after switching is sequentially written in a part of the area of the frame memory 9, and the written data is sequentially read out, and furthermore, this read/write area is expanded over time. It is something to control.

Next, the operation of the above embodiment will be explained.

When receiving a predetermined channel A, the CRT 17 operates in substantially the same manner as the conventional example, and the CRT 17 displays a high-quality moving image using a non-interlaced method, as shown in FIG. 2(a). At the time of channel switching, a detection signal is output from the channel switching detection circuit 21. Then, the memory controller 23 controls reading and writing of the frame memory 9 based on the detection output signal from the channel switching detection circuit 21 as follows.

(B) First, the video data of channel A written in the frame memory 9 immediately before switching is stored and then read out repeatedly. Therefore, the CRT 17 displays a still image corresponding to the video of channel A immediately before switching. .

(b) Next, the video data of channel B after switching is sequentially written into a part of the frame memory 9 corresponding to the center of the display screen.
It is read out together with the data of channel A that has not yet been rewritten. For this reason, the CRT 17 is
), the moving image of channel B is displayed in a small area in the center of the still image of channel A immediately before switching.

(c) As time passes, the area in which channel B video data is written to the frame memory 9 becomes wider, and the area in which channel A data is stored becomes narrower. Therefore, the CRT 17 displays the moving image of channel B in a large area in the center of the still image of channel A immediately before switching, as shown in FIG. 2(c).

(d) Then, after a predetermined period of time has elapsed, the video data of channel B is written to the entire area of the frame memory 9,
The area where channel A data is stored disappears. Therefore, the CRT 17 displays the moving image of channel B after switching over the entire screen, as shown in FIG. 2(d).

In the above embodiment, channel B after channel switching
The video first shows channel A before switching channels.
This channel B is displayed small in the center of the still image.
In this embodiment, the video screen expands similarly over time, but the present invention is not limited to this. When switching channels, the writing area of the video data of the channel after switching to the frame memory is The video screen of the channel after switching expands over time, and the still screen of the channel before switching shrinks over time by changing from a part of the memory area to the entire memory area over time. For example, when switching the channel from A to B as shown in Figure 3 (a) (b) (c) (d), the stationary surfaces of channel A before switching become similar over time. It may also be possible to shrink the image and make it disappear.

[Effect of the invention] A digital television receiver according to the present invention.

As mentioned above, based on the channel switching detection circuit that detects the channel switching of the tuner and the detection signal of this channel switching detection circuit, the writing area of the video data to the frame memory is changed over time from a part of the memory area. Equipped with a memory controller that changes all memory areas, when switching channels, the video screen of the channel before switching becomes static, and the video screen of the channel after switching expands over time, so switching Compared to the conventional example in which the video screen of the next channel is displayed instantly, it is possible to give a special effect to the image when switching channels, and it is possible for viewers to enjoy the change in the image when switching channels.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a digital television receiver according to the present invention, FIG. 2 is an explanatory diagram explaining the operation of FIG. 1, and FIG. 3 is an explanatory diagram explaining the operation of another embodiment. It is a diagram. 1...Tuner, 3...Antenna, 5...A/D
Conversion circuit, 9... Frame memory, 13... D/A
conversion circuit. 17...CRT (display unit), 21...Channel switching detection circuit, 23...Memory controller. Applicant Fujitsu General Ltd.

Claims (1)

[Claims] The video signal received by the antenna and tuned by the tuner is
/D converter circuit converts the video data into digital video data, writes this video data into frame memory, and D/A converter circuit converts the video data read from the frame memory into an analog video signal, which is displayed on the display unit. In the digital television receiver, a channel change detection circuit detects a channel change of the tuner, and a write area of video data in the frame memory is changed over time based on a detection signal of the channel change detection circuit. What is claimed is: 1. A digital television receiver comprising: a memory controller that changes from a part of the memory area to the entire memory area;