JPH06339122A - Hi-vision receiver playback device - Google Patents

Abstract

(57) [Abstract] [Purpose] To obtain a device for receiving MUSE high definition signals. [Structure] 4 band-divided by band-division filter 9
A still image processing circuit 4 that performs processing in the time axis direction only on high-frequency signals of MHz or higher, and a reconstruction filter 10 that synthesizes the processed high-frequency signal and low-frequency signal into a still-image signal,
Video processing circuit 3 that performs in-field processing for all bands
And a moving image / still image switching circuit 7 for switching and outputting the moving image signal and the still image signal according to the movement of the image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reproducing apparatus for a high-definition receiver which reproduces a high-definition signal transmitted by the MUSE system.

[0002]

2. Description of the Related Art FIG. 6 is a block circuit diagram showing a conventional high-definition receiver (reference document: MUSE-high-definition transmission system, edited by the Institute of Electronics, Information and Communication Engineers). In the figure, 1 is an input terminal, 2 is an A / D converter, 3 is a moving image processing circuit, 4 is a still image processing circuit, 5 is a motion detection circuit for detecting a moving part in the screen, and 6a and 6b are still image processing circuits. Is a frame delay memory, 6c is a field delay memory, 7 is a switching circuit for switching between a still image and a moving image, and 8 is an output terminal.

Next, the operation will be described. A high-definition signal transmitted by the MUSE method requires decompression processing because it is band-compressed. In this band compression, a still image area and a moving image area are distinguished from each other, and the processing is performed so that the resolution is high for the still image area and the motion tracking is good for the moving image area. . The decompression process is
The moving image process and the still image process are performed in parallel, and the two processes are appropriately switched depending on the detection of the motion area. This moving image processing is realized by field interpolation, and the still image processing is realized by interframe interpolation and interfield interpolation.

The MUSE high definition signal input from the input terminal 1 is converted into a digital signal by the A / D converter 2. MUS converted to digital signal
The E system high-definition signal (hereinafter referred to as “MUSE signal”) is input to the moving image processing circuit 3 and the still image processing circuit 4. The sampling frequency at this time is 16.2M.
Hz.

In the moving picture processing circuit 3, the MUSE signal is subjected to field interpolation. Field interpolation ensures correct interpolation for fast moving images. Since field interpolation is an operation with neighboring pixels in the same field, it does not require a large storage capacity.

In the still picture processing circuit 4, inter-frame interpolation and inter-field interpolation are applied to the MUSE signal. First, the input MUSE signal is written in the memory 6a, a signal delayed by one frame is obtained, a signal of the current frame and a signal delayed by one frame are calculated, and interframe interpolation is realized. In this interframe interpolation, the pixels of two frames are alternately used and the number of pixels is doubled. Therefore, the sample rate after interframe interpolation is 32.4 Msps. At this time, the memory capacity required for one frame delay is about 4 Mbits.

The signal interpolated between frames is stored in the memory 6c.
To interpolate by interleaving by interpolating by interpolating signals by interpolating by 1 field. The delay in the memory 6c is 1 field (1/2 frame), but since the sample rate is doubled, a memory capacity of about 4 Mbits is required like the frame delay.

The still picture signal thus obtained cannot be used in a moving part. Therefore, it is necessary to apply the output of the moving image processing circuit 3 to the moving portion and the output of the still image processing circuit 4 to the still image portion. For this reason, the motion detecting circuit 5 for detecting the moving part is required.

The motion detection circuit 5 compares the output of the A / D converter 1 with a signal delayed by one frame (or delayed by two frames) to determine whether it is in a motion region. In the case of the MUSE signal, there is no aliasing in the band of 4 MHz or less, so comparison with a signal delayed by one frame is sufficient. However, in the high-frequency part, a signal delayed by one frame causes movement in a moving part due to aliasing between frames. The detection cannot be done correctly. Therefore, a 2-frame delay signal is used for high-frequency motion detection.
For this reason, when high-frequency motion detection is required, another 1
A frame delay is required, and 4M bits are added as the memory 6b.

The switching circuit 7 switches between the output of the still image processing circuit 4 and the output of the moving image processing circuit 3 in accordance with the detection signal obtained by the motion detection circuit 5, and outputs the output to the output terminal 8. In this switching, the two outputs may be added at an appropriate ratio depending on the magnitude of the motion detection output.

[0011]

Since the conventional apparatus is configured as described above, about 8 to 12 megabits of image memory for two frames are required to perform still image processing, and the hardware scale is large. There was a problem that it would grow.

The present invention has been made to solve the above problems, and an object of the present invention is to obtain a reproducing apparatus for a high-definition receiver having a small memory capacity.

[0013]

According to the present invention, a MUSE signal is divided into a low frequency component and a high frequency component, and still image processing is applied only to the high frequency component. It is configured to combine the range components.

[0014]

According to the present invention, the capacity of the frame memory can be reduced while maintaining the image quality equivalent to that of the conventional method.

[0015]

【Example】

Example 1. Embodiment 1 of the present invention will be described below with reference to the drawings. In FIG. 1, the same reference numerals as those in FIG. 6 denote the same parts, respectively, 6 is a high-frequency memory for still image processing, and 9
Is a band division filter, and 10 is a reconstruction filter.

FIG. 2 is a block circuit diagram showing the configuration of the band division filter 9. Reference numeral 11 is a low pass filter, 12 is a high pass filter, and 13 and 14 are subsamplers.

Next, the operation will be described. The MUSE signal input from the input terminal 1 is sampled at a speed of 16.2 MHz. The MUSE signal digitized by the A / D converter 2 is input to the moving image processing circuit 3 and the band division filter 9, and in the moving image processing circuit 3, field interpolation is performed as in the conventional example.

On the other hand, M input to the band division filter 9
The USE signal is a signal of a low frequency component of 4 MHz or less (hereinafter referred to as “low frequency signal”) and a signal of a high frequency component of 4 MHz or higher (hereinafter referred to as “high frequency signal”) by the low frequency filter 11 and the high frequency filter 12. Called). Since the band of the MUSE signal is 8.1 MHz, this makes both the low-frequency signal and the high-frequency signal a signal having a bandwidth of about 4 MHz. In this way, the two band-divided signals have a half band compared to the original MUSE signal, so the sample rate can be reduced by half, 8.1 Msps. Subsampler 1
3 and 14 are used for this purpose, and the outputs of the sub-samplers 13 and 14 are 8.1 Msps, which is half the original MUSE signal sample rate of 16.2 Msps.

The high frequency band signal divided by the band division filter 9 is input to the still image high frequency band processing circuit 4 and subjected to inter-frame interpolation and inter-field interpolation. As shown in FIG. 3, the high frequency memory 6 includes a high frequency frame delay memory 6a,
6b and a high frequency field delay memory 6c. The high frequency signal is written in the high frequency frame delay memory 6a and delayed by one frame. By calculating the high frequency signal delayed by the frame and the high frequency signal output of the band division filter 9, a high frequency signal interpolated between frames can be obtained. The sample rate at this time is 16.2 Msps.

The sample rate of the high-frequency signal divided by the band division filter 9 is 8.1 Msps, which is half that of the original sample rate of 16.2 Msps. Therefore, the memory capacity required for the high-frequency frame delay memory 6a for storing this information is about 2 Mbits, which is half that in the case where band division is not performed.

In a similar manner, a high frequency signal (sample rate 16.2 Msps) interpolated between frames is written in the high frequency field delay memory 6c, delayed by one field, and calculated as a current field signal to calculate the inter-field signal. Achieve interpolation.

The memory capacity required for the high frequency field delay memory 6c is 2 Mbits as in the case of frame delay.

The interpolated high frequency signal thus obtained is combined with the low frequency signal output of the band division filter 9 by the reconstruction filter 10 to become a still image processed signal.

The still image processed signal is input to the moving image / still image switching circuit 7 and is appropriately switched to the output of the moving image processing circuit 3. The switching circuit 7 is controlled by the output of the motion detection circuit 5. The motion detection circuit 5 may require a signal delayed by two frames, but the required capacity of the high-frequency frame delay memory 6b required for this is about 2 Mbits, which is half that in the case where band division is not performed.

By the above operation, a reproduced high-definition signal can be obtained at the output terminal 8.

Example 2. FIG. 4 is a block circuit diagram showing a second embodiment of the present invention. The same reference numerals as those in FIG. 1 denote the same parts, respectively, and different points from the first embodiment of the second embodiment are as follows.
In the first embodiment, the moving image processing is performed on the entire band, but the moving image processing is limited to the high frequency component, and the low frequency component is input to the reconstruction filter 10 without any processing, and the moving image /
A reproduction output is obtained by synthesizing with a high-frequency signal subjected to still image adaptive processing.

In the second embodiment, since there is no interpolation processing in the low frequency component, deterioration of vertical resolution due to the interpolation processing can be prevented.

Example 3. FIG. 5 is a block circuit diagram showing a third embodiment of the present invention. The same reference numerals as those in FIG. 1 denote the same parts, 15 is a high band extraction filter, and 16 is a high band addition circuit.

In the present embodiment, the band division filter 9 in the first embodiment is replaced with a high band extraction filter 15 for extracting 4 MHz or more, and the high band component of the MUSE signal is extracted and stored in the high band memory 6.

In the motion detection circuit 5, the high band signal delayed by two frames by the high band memory 6 is compared with the output of the high band extraction filter 15 to detect the motion. 6, the high frequency signal delayed by one frame is added to the still image portion of the signal processed by the high frequency addition circuit 16.

Since the phase of the inter-frame folding component is inverted between frames, the folding information is removed by this addition. Of course, in this case, effective high frequency information cannot be reproduced, but the interference component can be reduced as compared with only simple field interpolation (moving image processing).

[0032]

As described above, according to the present invention, it is possible to obtain a reproducing apparatus for a MUSE high-definition receiver which realizes still image processing and aliasing removal similar to those of the conventional art with a small memory capacity.

[Brief description of drawings]

FIG. 1 is a block circuit diagram showing an HDTV receiver according to a first embodiment of the present invention.

FIG. 2 is a block circuit diagram of a configuration example of a medium band division filter according to the first embodiment.

FIG. 3 is a block circuit diagram showing a configuration of a high frequency memory according to the first embodiment.

FIG. 4 is a block circuit diagram showing an HDTV receiver according to Embodiment 2 of the present invention.

FIG. 5 is a block circuit diagram showing an HDTV receiver according to Embodiment 3 of the present invention.

FIG. 6 is a block circuit diagram showing an HDTV receiver according to a conventional example.

[Explanation of symbols]

 2 A / D converter 3 Video processing circuit 4 Still image processing circuit 5 Motion detection circuit 6 Memory 7 Video / still image switching circuit 9 Band division filter 10 Reconstruction filter 11 Low-pass filter 12 High-pass filter 13 Sub-sampler 14 Sub-sampler 15 High Band extraction filter 16 High band addition circuit

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[Procedure amendment]

[Submission date] September 9, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 1

[Correction method] Change

[Correction content]

Claims (6)

[Claims] 1. A device for receiving a high-definition MUSE signal, comprising a band-splitting filter and a memory,
Only the high frequency component of the high-definition signal is stored in the memory and the frame is delayed, the inter-frame inserted high frequency signal is obtained from this delayed signal and the high frequency component signal of the current frame, and the still image is reproduced using this high frequency signal. A playback device for a high-definition receiver configured as described above. 2. A means for reconstructing a low-frequency signal and a high-frequency signal after the processing, wherein the low-frequency component is subjected to moving image processing, only the high-frequency component is processed by appropriately switching the moving image still image. Item 1
Playback device for the HDTV receiver described. 3. The reproducing apparatus for a high-definition receiver according to claim 1, further comprising means for synthesizing a low-frequency component not subjected to the interpolation processing and a high-frequency signal subjected to the moving image / still image adaptive processing to obtain a reproduction output. 4. A reproducing apparatus for a high-definition receiver according to claim 1, further comprising means for detecting a motion signal for switching a moving image / still image only from a high frequency component. 5. The reproducing apparatus for a high-definition receiver according to claim 1, further comprising means for performing band division and re-combination during still image processing and switching to normal moving image processing according to a motion signal. 6. The reproducing apparatus for a high-definition receiver according to claim 1, further comprising means for removing only the aliasing interference without reproducing the still image.