JPH04263592A - Recorder - Google Patents

Abstract

PURPOSE:To record a MUSE signal as still picture data to reproduce a high- resolution still picture with less image blurring. CONSTITUTION:The MUSE signal from a BS tuner 2 is digitalized to be supplied to RAM 6A and 6B. The RAM 6A and 6B alternately become writing and reading states. In the RAM on the writing side, four fields of data is stored when moving information indicating complete still picture is detected by a detection circuit 34. On the other hand, when it is not detected, the four fields of data just before the changeover is stored. At the head of the four fields of data to be alternately read out from the RAM 6A and 6B, synchronizing pattern signals PS are added respectively and supplied to a DAT 50 for recording. The resolution as one screen of taken since the four fields of data is recorded as one screen of the still picture data. Further, since the complete still picture data is recorded preferentially, the high-quality still picture with less image blurring can be reproduced.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording apparatus for recording, for example, a MUSE signal as still image data.

0002

[Prior Art] As a method for compressing the transmission signal band of television signals, MUSE (Multiple Sub-
nyquist Sampling Encoding
) is known. In the MUSE encoder, band compression is performed by line offset subsampling in the motion system, and by field offset and frame offset subsampling in the stationary system.

On the other hand, in the MUSE decoder, in the motion system, an image is reproduced using only the signal of the current field through intra-field interpolation, and in the stationary system, the image is reproduced using the signals of the current field and the past three fields through inter-frame and inter-field interpolation. be done. As a result, the full resolution is achieved in a stationary system, and blurring of the image is prevented, although the resolution is reduced to 1/4 in a moving system.

[0004] In the MUSE system, a high-definition television signal (video signal bandwidth = 20 MHz) is band-compressed and transmitted. According to the high-definition standard, the number of scanning lines per frame is 1125, the interlace ratio is 2:1, the aspect ratio is 16:9, the field frequency is 60 Hz, and the line frequency is 33,750 Hz.

FIG. 7 shows the format of a television signal (hereinafter referred to as "MUSE signal") transmitted using the MUSE method. The MUSE signal has 480 samples of data on each of 1125 horizontal lines, with a frame pulse added to the beginning of each frame and a horizontal synchronization signal added to the beginning of each line.

[0006]

By the way, it is conceivable to record such a MUSE signal as still image data, for example, on a DAT (digital audio tape recorder).

[0007] When extracting data for one screen as still image data from a MUSE signal for a moving image, it is necessary to extract it in units of one field in order to prevent image blurring, but the resolution decreases (in the case of the NTSC system). The quality is comparable to that of a still frame image). If the image is extracted in units of 4 fields to obtain the full resolution, image blur will occur in areas with movement.

[0008] Note that the MUSE signal is sampled at 16.2 MHz, and in the case of 4 fields (2 frames),
1125×2×480=1,080,000 samples. If 1 sample is 8 bits, 8,640,000
bit (≒8.24 Mbit).

[0009] If these four fields' worth of data were to be recorded as still image data on a DAT, the data recording speed on the DAT would be 1,536,000 bits (48 kHz).
× 2 channels × 16 bits)/sec, so 5.62
It will take 5 seconds. In other words, in a video system, 4×1
/60≒66.7ms worth of data is 5 in the DAT system.
．． This is 625 seconds worth of data.

The present invention provides a recording device that records MUSE signals as still image data so that still images with less image blur and high resolution can be reproduced.

[0011]

[Means for Solving the Problems] The present invention provides a recording device that sequentially updates and writes MUSE signals in memory means on a screen-by-screen basis, reads out data stored in the memory means after a predetermined period of time, and records the data as still image data. , M.U.
A motion information detecting means for detecting motion information from a control signal of the SE signal is provided, and writing of the MUSE signal into the memory means is controlled based on a detection signal from the motion information detecting means.

0012

[Operation] Bit No. of control signal of MUSE signal
．． 16 to 18 contain motion information. Based on the detection signal detected by the motion information detection means, it can be determined whether the data being written in the memory means is still image data or moving image data. For example, when the data is a completely still image, if you stop writing data from the next screen to the memory means, the completely still image data will be stored in the memory means after a predetermined period of time, and this will be recorded as still image data. be done. Therefore, even if the still image data is recorded in units of four fields, it is possible to prevent image blurring from occurring in the reproduced still image.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. This example is an example in which the MUSE signal is recorded as still image data using DAT.

FIG. 1 shows the configuration of the recording system. In the figure, a satellite broadcast signal captured by a satellite broadcast (BS) antenna 1 is supplied to a BS tuner 2. B.S.
The MUSE signal output from the tuner 2 is band-limited by a low-pass filter 3, further converted into a digital signal by an A/D converter 4, and then transferred to sides a and b of a changeover switch 5.
It is supplied to RAMs 6A and 6B as buffers via the side.

The output signal of the A/D converter 4 is supplied to a synchronization detection circuit 7, and the frame pulse signal and horizontal synchronization signal detected by the synchronization detection circuit 7 are supplied to a controller 8. The controller 8 has a frequency of 48kHz x 4 = 192kHz from the DAT50 in order to synchronize with the DAT50.
A system clock CLK is supplied.

The output signal of the A/D converter 4 is also supplied to a motion information detection circuit 34. This detection circuit 34 detects the bit number of the control signal. The movement information for 16 to 18 is
The signal is supplied to the controller 8.

The control signal present in the format of the MUSE signal shown in FIG. 7 has two samples as one bit, and
It is multiplexed as a binary signal. The code format is an extended Hamming (8,4) code. The generation matrix and binary levels are determined as shown in FIG. However, the left 4 bits of the generation matrix are used as information points, and the right 4 bits are used as inspection points, and are transmitted from the left. The control signal has 32 bits in total, and when divided into 4 bits each, it becomes 8 blocks, which are sent three times in a row. FIG. 5 shows the multiplexing positions of control signals, and the portion E is not used in a normal MUSE decoder. FIG. 6 shows the contents of the 32-bit control signal.

Writing and reading to and from RAMs 6A and 6B are controlled by a controller 8.
6B, when one is in the write state, the other is in the read state. In other words, M in RAM6A or 6B.
When data for 4 fields of the USE signal is written as still image data, RAM 6B or 6A is written respectively.
to DAT50 data recording speed (1,536,000
Four fields of data are read out in synchronization with the data rate (bits/second). In this case, data for 4 fields (8, 6
40,000 bits) is read out with a time of 5.625 seconds.

Here, while data for four fields is read from one RAM at a recording speed of DAT50, many field signals are supplied as write signals to the other RAM, and the data contents are sequentially updated. Four fields of data are always stored.

After the reading of four fields of data from one RAM is completed, the write and read states of the RAMs 6A and 6B are switched. At this time, the contents of the four fields of data stored in the other RAM are controlled according to the motion information supplied from the detection circuit 34 to the controller 8.

That is, writing to RAM6A, 6B,
If it is recognized from the motion information that the data being written is a completely still image before the read state is switched, writing of data from the next screen to the other RAM is stopped. Although not mentioned above, the motion information detected in each field of the MUSE signal relates to the next field. Therefore, if the motion information detected in a certain field indicates a completely still image, if that field is set as the third field, the data in the 0th to 3rd fields or the 1st to 4th fields will be completely still. This is still image data. From this, the other R
AM includes, for example, the 0th to 3rd fields, or the 1st field.
~The data of the fourth field is written, and then writing is stopped. Therefore, when the writing and reading states of the RAMs 6A and 6B are switched, the data of a completely still image is stored in the other RAM.

On the other hand, if the data being written is not recognized as a completely still image based on the motion information before the writing and reading states of the RAMs 6A and 6B are switched, writing to the other RAM is not stopped. , the data contents are updated sequentially. Therefore, RAM6A, 6B
When the writing and reading states of the two RAMs are switched, data for four fields immediately before the switching is stored in the other RAM.

Still image data read from the RAMs 6A and 6B is supplied to the a side of the changeover switch 10 via the a side and b side of the changeover switch 9, respectively. Switching of the changeover switches 5 and 9 is controlled by a controller 8. The selector switch 5 is set to a when the RAM 6A is in the write state.
When connected to the side and RAM6B is in the write state b
connected to the side. The changeover switch 9 is connected to the a side when the RAM 6A is in the read state, and is connected to the b side when the RAM 6B is in the read state.

Reference numeral 11 denotes a synchronization generation circuit, and a synchronization pattern signal PS outputted from this synchronization generation circuit 11 is supplied to a fixed terminal on the b side of the changeover switch 10. The operation of the synchronization generating circuit 11 and the switching of the changeover switch 10 are controlled by the controller 8.

That is, immediately before data for four fields is supplied to the a side of the changeover switch 10, the synchronization generation circuit 1
1 outputs a synchronization pattern signal PS. Although not mentioned above, the reading of four fields of data from the RAMs 6A and 6B is started after the synchronization pattern signal PS is output. In addition, the changeover switch 10 has 4
When data for a field is supplied, it is connected to side a, and when synchronization pattern signal PS is supplied to side b, it is connected to b.
connected to the side.

Therefore, the changeover switch 10 outputs the synchronization pattern signal P at the beginning of each of the four fields of data.
The output with S added is output (shown in Figure 3), which is D
The signal is supplied to the AT 50 and recorded.

Next, FIG. 2 shows the configuration of the reproduction system. In the figure, four fields of data (still image data) sequentially reproduced from the DAT 50 are transferred to the RAM 22 as a buffer via the a side and b side of the changeover switch 21.
A and 22B are alternately supplied and written.

The reproduction signal of the DAT 50 is transmitted to the synchronization detection circuit 23.
is supplied to This synchronization detection circuit 23 uses a synchronization pattern signal PS added to the beginning of four fields of data.
is detected, and the detection signal SD is sent to the controller 24.
It is supplied as a signal (cue signal) indicating the start timing of a field's worth of data. Further, the controller 24 is supplied with a 192 kHz system clock CLK from the DAT 50.

Writing and reading of RAMs 22A and 22B are controlled by controller 24 based on detection signal SD and system clock CLK. Changeover switch 2
1 is controlled by the controller 24, and R
When the AM 22A is in the write state, it is connected to the a side, and when the RAM 22B is in the write state, it is connected to the b side.

When one of the RAMs 22A and 22B is in a write state, the other is in a read state. In other words, when data for four fields of the MUSE signal is written to RAM 22A or 22B, each RAM
Four fields of data are repeatedly read from 22B or 22A in synchronization with a 16.2 MHz clock. In this case, after writing of data for four fields to one RAM is completed, the write and read states of the RAMs 22A and 22B are switched.

Four fields of data (still image data) according to the format of the MUSE signal repeatedly output from the RAMs 22A and 22B are transferred to the selector switch 25 a.
The signal is supplied to the MUSE decoder 28 via the side and b side. Switching of the changeover switch 25 is controlled by the controller 24, and when the RAM 22A is in the read state, it is connected to the a side, and when the RAM 22B is in the read state, it is connected to the b side.

The video signals (for example, R, G, B signals) output from the MUSE decoder 28 are supplied to a monitor television 29, and a still image is displayed on the monitor television 29.

In this example, when the motion information detected by the motion information detection circuit 34 indicates a completely still image, data for four fields of the completely still image is stored in the RAMs 6A and 6B, and this Data for four fields is recorded as still image data for one screen using DAT50. Therefore, since complete still image data is recorded with priority, even if four fields of data are recorded as one screen's worth of still image data to obtain full resolution, high quality still images with almost no image blur will be recorded. Images can be played back.

In the above-mentioned embodiment, completely still image data is recorded, but the motion information detected by the motion information detection circuit 34 may indicate either a completely still image or a quasi-still image. If so, save that data to RAM.
The data may be stored in 6A and 6B and recorded in DAT50. This is effective when the probability of a completely still image appearing is low.

Further, if the motion information detected by the motion information detection circuit 34 indicates either a completely still image or a semi-still image, the data is stored in the RAMs 6A and 6B. When data is stored, if motion information indicating a completely still image is subsequently detected, the data of the completely still image is stored in RAM6A, 6B, and the data of the completely still image is stored in RAM6A, 6B. If so, record the data on DAT50 and store it in RAM.
If only quasi-still image data is stored in 6A and 6B, that data may be recorded on the DAT50. In this case, even after the semi-still image is stored in the RAMs 6A and 6B, if motion information indicating a completely still image is detected, the data of the completely still image is stored in the RAM 6A, 6B.
It is necessary to store it in 6B. That is, RAM6A, 6
B includes first and second memory sections, and even after quasi-still image data is stored in the first memory section, it is necessary to continue writing data to the second memory section.

Furthermore, in the above embodiment, the RAM 6A
, 6B, if no motion information indicating a completely still image is detected before the writing and reading states of 6B are switched, the RAM is switched to the writing state and the previous 4
Fields worth of data are stored and recorded by the DAT50, but without switching the writing and reading states of RAM6A and 6B, data for four fields of the completely still image recorded immediately before can be transferred to RAM6A and RAM6B.
6B may be read out and recorded again. This means that when motion information indicating either a completely still image or a quasi-still image is detected, the data is
It can be similarly applied to what is stored and recorded in AM6A and AM6B.

Furthermore, in the above embodiment, the synchronization pattern signal PS is added to the beginning of four fields of data, but the recording system adds dummy data of a predetermined length (for example, 128 level continuous data). , 0 level and 2
It is also possible to add 55 levels of alternating continuous data, etc.), and the reproduction system can detect the end of this dummy data and recognize the start of four fields of data.

Furthermore, in the above embodiment, two RA
Although M6A and 6B (22A, 22B) are used, it is also possible to use one or three or more. However, when there is only one, the recording system
Continuous supply to AT50 becomes difficult.

[0039]

According to the present invention, based on the motion information detected by the motion information detecting means, for example, complete still image data is preferentially recorded, so in order to obtain the full resolution, four fields' worth of data is recorded with priority. Even if the data is recorded as still image data for one screen, there is little image blurring and high quality still images can be reproduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a recording system according to an embodiment.

FIG. 2 is a block diagram showing the configuration of a reproduction system according to the embodiment.

FIG. 3 is a diagram showing the structure of recorded data of DAT.

FIG. 4 is a diagram for explaining the format of a control signal of a MUSE signal.

FIG. 5 is a diagram showing multiplexing positions of control signals of the MUSE signal.

FIG. 6 is a diagram showing the contents of a control signal of the MUSE signal.

FIG. 7 is a diagram showing the format of a MUSE signal.

[Explanation of symbols]

2 BS tuner 6A, 6B, 22A, 22B RAM 7, 23 Synchronization detection circuit 8, 24 Controller 11 Synchronization generation circuit 28 MUSE decoder 29 Monitor TV 34 Motion information detection circuit 50 DAT

Claims (5)

[Claims] 1. A recording device that sequentially updates and writes a MUSE signal in a memory means for each screen, reads out data stored in the memory means after a predetermined period of time, and records the data as still image data, wherein a control signal for the MUSE signal is provided. 1. A recording apparatus comprising a motion information detecting means for detecting motion information, and controlling writing of the MUSE signal to the memory means based on a detection signal from the motion information detecting means. 2. When the motion information detection means detects that the data being written in the memory means is a completely still image within the predetermined time, the writing to the memory means from the next screen is stopped. 2. The recording device according to claim 1, wherein the recording device is configured to: 3. If the motion information detecting means detects that the data being written in the memory means is a completely still image or a semi-still image within the predetermined time, the memory means reads data from the next screen. 2. The recording device according to claim 1, wherein writing to the recording device is stopped. 4. The memory means includes first and second memory sections, and the MUSE signal is stored in the first and second memory sections on a screen-by-screen basis.
and a second memory section in parallel, and the data being written into the first and second memory sections is completely still or semi-still by the motion information detecting means within the predetermined time. When it is detected that the image belongs to a still image, writing to the first memory section is stopped from the next screen, and when it is detected that it is a quasi-still image, writing to the first memory section is stopped. Then, when the motion information detecting means detects that the data being written in the second memory section is a completely still image within the predetermined time, writing from the next screen to the second memory section is performed. If complete still image data is stored in either the first or second memory section after the predetermined time, the data is read out from that memory section and recorded, and after the predetermined time, the Quasi-still image data is stored in the first memory section, and the second
2. The recording apparatus according to claim 1, wherein when data of a complete still image is not stored in the memory section, the data is read out from the first memory section and recorded. 5. The memory means includes first and second memory sections, and when one of the first and second memory sections is in a writing state, the other is in a reading state, and the MUSE signal is transmitted on a screen-by-screen basis. and sequentially update and write data in the first or second memory section, and within the predetermined time, the motion information detecting means detects that the data being written in the first or second memory section is a completely still image or a semi-still image. If it is detected that it is, the writing to the first or second memory section from the next screen is stopped, and the write and read states of the first and second memory sections are checked after the predetermined time. If the motion information detecting means does not detect that the data being written in the first or second memory section is a completely still image or a semi-still image within the predetermined time, the 2. The recording apparatus according to claim 1, wherein the writing and reading states of the first and second memory sections are not switched.