JPH04373283A - Video signal recording/reproducing device - Google Patents

Abstract

PURPOSE:To interpolate moving pictures which involve scene changes and violent movements without degrading a picture quality. CONSTITUTION:An ECC decoding circuit 34 corrects errors, if there is any error in reproduced data and in addition to that hoists a flag. A movement information detecting circuit 69 detects a movement information in a reproduced signal, and if the detected result indicates a still picture or a quasi-still picture, a terminal 69a or a terminal 69b is designated as '1'. In that case, an inter-field interpolating circuit 48 carries out inter-frame interpolation by using a frame memory 60. Mean while, the movement information detecting circuit 69, if the detected result indicates scene changes or prefect animation, makes a terminal 69c or 69d hoist a1'. In this case, the in-field interpolation signal of an in-field interpolation circuit 66 is made to pass through as it is. By this, even scene changes and moving pictures accompanied by violent movements can be interpolated with less degraded picture quality.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention applies to HDTV (High
MUSE (Multiple Sub-Ny) is used for Definition Television) broadcasting.
The present invention relates to a video signal recording and reproducing device for a video signal (hereinafter referred to as a MUSE signal) compressed by a MUSE signal.

0002

2. Description of the Related Art FIG. 3 shows a transmission signal for one frame of a MUSE signal. The transmission signal for one frame of the MUSE signal consists of 1125 lines, and is transmitted sequentially for each line. In the figure, Y is a luminance signal obtained by analogizing sample values, and C is a color signal obtained by analogizing sample values.
A is an audio signal that has been converted into a 3-level audio signal once digitized, FP/VIT is a signal containing information such as transmission path equalization (VIT) and frame pulse (FP), GU is a guard space, and CON is described later. control signal, B
L is a symbol corresponding to empty data, and CP is a symbol corresponding to clamp level information. The numerical values shown in FIG. 3 indicate the number of data in the digital domain before converting the transmission signal to analog.

The control signal CON has 32 bits per field. Since this is very important when decoding on the receiving side, a total of 64 bits (Hamming code) with 32 bits of parity added are sent three times in a row in consideration of errors during transmission. For example, in the first field, there are 12 to 106 samples from 559 to 563 lines,
I have sent it 3 times in a row. The 16th, 1st of the control signal CON
Motion information is expressed in 3 bits consisting of 7 and 18 bits, where "0" is normal, "1" is a completely still image, and "2"
is a semi-still image, "3" is a scene change, "4" to "6"
” indicates the degree of movement, and “7” indicates a complete video. Also, the first
The 9th bit is a signal for controlling the reception mode, "0" is the standard method, "1" is the non-standard method, and the 20th bit is A.
M/FM, and "1" indicates AM and no emphasis.

Other contents of the control signal CON and the detailed structure of other symbols are explained in detail in Chapter 3 of "High Vision Technology" edited by NHK Broadcasting Technology Research Institute, published on November 25, 1985. .

[0005] A MUSE signal as shown in FIG. 3 is FM-modulated and transmitted from the transmitting side using one satellite channel.

FIG. 4 shows a conventional digital VTR 100 that receives, records and reproduces the MUSE signal transmitted as described above.
This is shown as an example. This digital VTR100
is a VTR main body 100a, an input side MUSE decoder 100b connected to the input side of the VTR main body 100a, and a VTR main body 100a.
Output side MUSE connected to the output side of the TR main body 100a
It is roughly composed of a decoder 100c.

[0007] The VTR main body 100a has an ECC addition circuit 2.
4, modulation circuit 26, demodulation circuit 32 and ECC decoding circuit 3
4th grade. The input side MUSE decoder 100b includes an FM demodulator 12, an A/D converter 14, an equalizer 16, a de-emphasis circuit 18, etc., and the output side MUSE decoder 100c includes an interfield interpolation circuit 48, an intrafield It includes an interpolation circuit 50, an adder 52, a matrix 54, a D/A changer 56, a frame memory 60, and the like. In the same figure, 1
0, 20, 22, 28, 30, 36, 38, 44, 46
, 58 indicate input/output terminals.

The MUSU signal transmitted to the input terminal 10 of the input side MUSE decoder 100b is demodulated by the FM demodulator 12 into an analog MUSE signal having the format shown in FIG. The analog MUSE signal is then converted into a 10-bit digital MUSE signal by the A/D converter 14. Furthermore, this digital MUSE signal is corrected for distortion caused by the transmission path by an equalizer 16, and is subjected to de-emphasis corresponding to the emphasis during transmission by a de-emphasis circuit 18, becoming an 8-bit digital MUSE signal, which is sent to the output terminal 20. via VT
It is supplied to the input terminal 22 of the R main body 100a.

In the VTR body 100a, the 8-bit digital MUSE signal supplied to the input terminal 22 is
After parity and synchronization signals for error correction are added in the C addition circuit 24, the modulation circuit 26 performs digital modulation according to the recording/reproduction characteristics, and the data is transferred to the magnetic tape via the reproduction head by a recording amplifier (not shown). recorded.

[0010] MUSE played by this playback head
The signal is digitally demodulated by the demodulation circuit 32, and a digital MUSE signal with parity is decoded. Next, the ECC decoding circuit 34 uses parity to perform error correction if there is an error in the reproduced data, and outputs the corrected digital MUSE signal to its output line 34a. On the other hand, if the error correction is not complete, the data is output to the output line 34a and an error flag is output to the output line 34b.

The reproduced MUSE signal is sent to the output terminal 36.
It is supplied to the data input terminal 38 of the output side MUSE decoder 100c via
, 40b.

On the other hand, the error flag is supplied to the dropout signal input terminal 46 of the output side MUSE decoder 100c via the output terminal 44, and becomes a switching signal for the switch 42.

On the output side MUSE decoder 100c side,
When there is no signal at the dropout signal input terminal 46, the switch 42 selects the 42a side, and the interfield interpolation circuit 48, the intrafield interpolation circuit 50, and the adder 52 perform the following operations according to motion detection information (not shown). Normal video signal decoding processing is performed, and the analog R. G. B. The signal is sent to the output terminal 58
The signal is output to the monitor connected to the output terminal 58.

On the other hand, when the error flag is output to the dropout signal input terminal 46, the switch 42 selects the 42b side, that is, the output of the frame memory 60;
Interframe interpolation is therefore performed to compensate for dropouts. The subsequent processing is the same as when no error flag is set.

[0015]

[Problems to be Solved by the Invention] By the way, the video signal recording and reproducing device 100 described above is originally installed in the output side MUSE decoder 100c when an error flag is set (when a dropout occurs in an analog VTR or VDP). Interframe interpolation (dropout compensation) is performed using the frame memory 60 that is provided. Therefore, although it is effective in preventing image quality deterioration without adding hardware on the playback device main body 100a side, only inter-frame interpolation can be performed, so for images with scene changes or rapid movement,
There was a problem in that it caused a large deterioration in image quality.

SUMMARY OF THE INVENTION The present invention has been made in view of the above embodiments, and an object of the present invention is to provide a video signal recording and reproducing device that is capable of interpolating moving images with scene changes and rapid movement with little deterioration in image quality. do.

[0017]

[Means for Solving the Problems] In order to achieve the above object, the present invention records a control signal including a compressed video signal and motion information on a recording medium, and transmits the video signal reproduced from the recording medium to the control signal. A video signal recording and reproducing apparatus that decodes according to a signal is characterized in that a video signal interpolation method is adaptively switched according to the contents of an error flag based on the reproduced video signal and the motion information.

[0018]

[Operation] Next, the operation of the video signal recording and reproducing apparatus having the above structure will be explained.

By analyzing the content of motion information included in the reproduced video signal, it is possible to identify whether the reproduced image is a completely still image, semi-still image, sea change, complete moving image, etc. The optimal interpolation method differs depending on the situation. Therefore, when an error flag is raised, optimal decoding can be achieved by analyzing the content of the motion information and adaptively switching the video signal interpolation method according to the content.

For example, as a result of analyzing the content of motion information,
Inter-frame interpolation is suitable when the image is a completely still image or semi-still image, and intra-field interpolation is suitable when the image is a sea change or completely moving image. By adaptively switching the interpolation method in this way, it is possible to perform interpolation with little deterioration in image quality even for moving images with scene changes or rapid movement.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic diagram of a video signal recording and reproducing apparatus 200 according to a first embodiment of the present invention. This device 200 includes a video signal recording and reproducing device main body 200a, and an input side MUSE decoder 1 similar to the conventional reproducing device 100 shown in FIG.
00b and an output side MUSE decoder 100c.

The playback device main body 200a has an ECC addition circuit 2 similar to the conventional playback device main body 100a shown in FIG.
4, modulation circuit 26, demodulation circuit 32 and ECC decoding circuit 3
4, a control signal detection circuit 68, an intra-field interpolation circuit 66, and other AND gates 61, 62, OR
It is roughly configured to include gates 70, 72, and a switch 64.

As described in the prior art section, the ECC decoding circuit 34 takes in the digital MUSE signal demodulated by the demodulation circuit 32, and uses parity to correct any errors in the reproduced data. , the corrected digital MUSE signal is output to the output line 34a. On the other hand, if the error correction cannot be completed completely, the data is output to the output line 34a and an error flag is output to the output line 34b. This outputs the following. Further, the ECC decoding circuit 34 has a digital M
The USE signal is supplied to the intra-field interpolation circuit 66 and also to the control signal detection circuit 68.

The control signal detection circuit 68
It is provided with a motion information detection circuit 68a that detects motion information based on the control signal CON in the digital MUSE signal taken in from the CC decoding circuit 34. This motion information detection circuit 68a detects the 16th, 17th, 1st motion information in the control signal CON of FIG.
Decode the 8-bit 3-bit output, and send it to terminal 69a if it is a completely still image, or to terminal 69b if it is a semi-still image.
When a scene changes, "1" is output to the terminal 69c, and when a complete moving image is displayed, "1" is output to the terminal 69d.

Next, the operation of the video signal recording/reproducing apparatus 200 of the first embodiment will be explained.

The MUSU signal transmitted to the input terminal 10 of the input side MUSE decoder 100b becomes an 8-bit digital MUSE signal and is sent to the VTR via the output terminal 20.
It is supplied to the input terminal 22 of the main body 200a. Input terminal 2
The digital MUSE signal supplied to 2 is added with parity and synchronization signals for error correction by an ECC addition circuit 24, and then digitally modulated by a modulation circuit 26 according to the recording/reproducing characteristics, and is then converted into a recording signal (not shown). The information is recorded on a magnetic tape by an amplifier via a playback head. Next, the MUSE signal reproduced by this reproduction head is digitally demodulated by the demodulation circuit 32, and the digital MUSE signal with parity is decoded. Next, the ECC decoding circuit 34 uses parity to perform error correction if there is an error in the reproduced data, and outputs the corrected digital MUSE signal to its output line 34a. On the other hand, if the error correction is not complete, the data is output to the output line 34a and an error flag is output to the output line 34b.

If there is no error in the reproduced data, that is, if the error flag is not set on the output line 34b of the ECC decoding circuit 34, both the AND gates 61 and 62 output (the logic is set to "0"). becomes “0”,
The switch 64 selects the 64b side and the switch 42 selects the 42a side, and neither intra-field interpolation nor inter-frame interpolation is performed.

Also, the output line 34 of the ECC decoding circuit 34
When an error flag is set in b and "1" is set at the terminal 69a or terminal 69b of the motion information detection circuit 69 (both terminals 69c and 69d are "0" in the case of a still image or a semi-still image).
In this case, the output of the gate 61 remains "0" and intra-field interpolation is not performed, and the output of the gate 62 becomes "1" and the switch 42 selects the 42b side, that is, inter-frame interpolation is performed.

On the other hand, the output line 3 of the ECC decoding circuit 34
4b is set and the terminal 69c or terminal 69d of the motion information detection circuit 69 is set to "1" (both terminals 69a and 69b are "0" in the case of a scene change or a complete moving image), the gate 61 is set to "1". The output changes to "1", and the switch 64 selects the side 64a, that is, the output of the intra-field interpolation circuit 66. On the other hand, the output of the gate 62 becomes "0", and the switch 42 selects the 42a side, that is, passes the intra-field interpolation signal selected by the switch 64 as is.

The MUS supplied to the data input terminal 38 of the output side MUSE decoder 100c via the output terminal 36
As explained in the section of the prior art, when there is no signal at the dropout signal input terminal 46, the E signal is subjected to normal video signal decoding processing and converted into an analog R.E signal. G. B. A signal is output to output terminal 58 and sent to a monitor connected to output terminal 58. On the other hand, when the error flag is output to the dropout signal input terminal 46, the switch 42 selects the 42b side, that is, the output of the frame memory 60, and therefore interframe interpolation is performed to compensate for dropouts.

According to the above-described first embodiment device 200, when reproducing the MUSE signal, motion information such as a scene change that has already been created by the MUSE decoder is detected at the time of reproduction, and the motion information is detected from the ECC decoding circuit. For still images or semi-still images, MUSE
Interframe interpolation is performed using the frame memory provided on the decoder side, and the intra-field interpolation circuit 66 in the playback device main body 200a is used for images with rapid movement such as scene changes or complete moving images. , it becomes possible to perform highly accurate interpolation without adding large amounts of hardware, and it is possible to reduce image quality deterioration.

In addition, the intra-field interpolation circuit 66 is realized by using pre-interpolation using one pixel delay, pre-line interpolation using 1H delay, etc., but it is extremely small-scale compared to inter-frame processing. All you need is hardware.

FIG. 2 shows a reproduction device 2 according to the first embodiment of the present invention.
FIG. 2 is a schematic configuration diagram of a video signal recording and reproducing apparatus 300 according to a second embodiment of the present invention, which is a modification of No. 00. Components having the same functions as the playback device 200 of the first embodiment are given the same reference numerals, and detailed explanation thereof will be omitted.

The present device 300 includes a video signal recording and reproducing device main body 200a, an input MUSE decoder 100b similar to the reproducing device 200 of the first embodiment of the present invention shown in FIG. It is roughly composed of a decoder 300c.

This device 300 includes an intra-field interpolation circuit 6 from the playback device main body 200a of the first embodiment shown in FIG.
6 is moved to the output side MUSE decoder 300c,
The playback device main body 300a includes an ECC addition circuit 24, a modulation circuit 26, and a modulation circuit 26 similar to the playback device main body 200a of the first embodiment.
Demodulation circuit 32, ECC decoding circuit 34, control signal detection circuit 68, and other AND gates 61, 62, OR
It has a general configuration including gates 70 and 72.

[0037] Furthermore, the output side MUSE decoder 300c is
Output side MUSE decoder 20 of the first embodiment shown in FIG.
An intra-field interpolation circuit 53 is connected between the 0c adder 52 and the matrix 54.

Next, the operation of the video signal recording/reproducing apparatus 300 of the second embodiment will be explained.

Similar to the first embodiment, when a MUSE signal is reproduced from a reproduction head (not shown), this MUSE signal is digitally demodulated by the demodulation circuit 32, and a digital MUSE signal with parity is decoded. Next, the ECC decoding circuit 34 uses parity to perform error correction if there is an error in the reproduced data, and outputs the corrected digital MUSE signal to its output line 34a. On the other hand, if the error correction is not complete, the data is output to the output line 34a and an error flag is output to the output line 34b.

If there is no error in the reproduced data, that is, if the error flag is not set on the output line 34b of the ECC decoding circuit 34, both the AND gates 61 and 62 output (the logic is set to "0"). becomes “0”,
The switch 42 selects the 42a side, and neither intra-field interpolation nor inter-frame interpolation is performed.

Also, the output line 34 of the ECC decoding circuit 34
When an error flag is set in b and "1" is set at the terminal 69a or terminal 69b of the motion information detection circuit 69 (both terminals 69c and 69d are "0" in the case of a still image or a semi-still image).
In this case, the output of the gate 61 remains “0” and the output of the terminal 63,
65, the intra-field interpolation circuit 53 is set to through mode 1, intra-field interpolation is not performed, the output of the gate 62 becomes "1", and the switch 42 selects the side 42b, that is, inter-frame interpolation is performed.

On the other hand, the output line 3 of the ECC decoding circuit 34
When an error flag is set at 4b and "1" is set at the terminal 69c or terminal 69d of the motion information detection circuit 69 (both terminals 69a and 69b are "0" in the case of a scene change or a complete moving image), the gate 62 is set. The output is "0", the switch 42 selects the 42a side, and the output of the gate 61 is
The flag changes to "1" and sets the intra-field interpolation circuit 53 to interpolation mode. Therefore, the ECC-decoded MUSE signal is transmitted to the intra-field interpolation circuit 50 and the inter-field interpolation circuit 48.
After the signal becomes a baseband signal through the MUSE decoding process, intra-field interpolation is performed.

According to the second embodiment device 300 described above, when reproducing a MUSE signal, similar to the first embodiment device 200, movements such as a scene change that have already been created by the MUSE decoder are used. Detects information during playback and
The echo flag from the CC decoding circuit is also used, and for still images or semi-still images, interpolation is performed using the frame memory originally provided on the MUSE decoder side, such as scene changes and complete moving images. Since the attached intra-field interpolation circuit 53 is used for images with rapid movement, highly accurate interpolation is possible without adding large hardware, and image quality deterioration can be reduced.

Similarly to the first embodiment device 200, the intra-field interpolation circuit 53 is realized by using pre-interpolation using a one-pixel delay, pre-line interpolation using a 1H delay, etc. Compared to the frame memory 60, extremely small-scale hardware is required. Furthermore, if it is combined with the field interpolation circuit 50 when integrated into an LSI, the cost will hardly increase.

[0045] Note that the present invention is not limited to the above embodiments,
Various modifications can be made without changing the gist of the invention. In the above embodiment, a digital VTR was explained, but an analog VTR may of course be used. In this case, the error flag becomes a dropout detector, and an analog delay line or a delay line using a CCD can be used for the 1 pixel delay or 1H delay of the intra-field interpolation circuit. It may also be a playback device such as a digital or analog video disc.

[0046]

According to the present invention described in detail above, since the video signal interpolation method is adaptively switched according to the contents of the error flag and motion information based on the reproduced video signal, It is possible to provide a video signal recording and reproducing device that can perform interpolation with little deterioration in image quality for moving images with rapid changes and movements.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of a video signal recording and reproducing apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a video signal recording and reproducing apparatus according to a second embodiment of the present invention.

FIG. 3 is a diagram showing a transmission signal for one frame of a MUSE signal.

FIG. 4 is a schematic configuration diagram of a conventional video signal recording and reproducing device.

[Explanation of symbols]

66 Intra-field interpolation circuit 68 Control signal detection circuit 68a Motion information detection circuit 200 Video signal recording and reproducing device

Claims (1)

[Claims] 1. A video signal recording and reproducing apparatus that records a compressed video signal and a control signal including motion information on a recording medium, and decodes the video signal reproduced from the recording medium according to the control signal, wherein the reproduced video signal A video signal recording and reproducing device characterized in that a video signal interpolation method is adaptively switched according to the contents of an error flag based on the signal and the motion information.