JPH03250987A - Recorder - Google Patents

Abstract

PURPOSE:To release the restriction of a consecutive shot speed due to the recording speed and to improve the consecutive shot speed by storing a picture data by the consecutive shot once to a 1st storage means and transferring the data to a 2nd storage means later at a low speed. CONSTITUTION:A 1st picture data is fed to a data area M1 during consecutive shot and 2nd and succeeding picture data are stored in other data area M2 while being sequentially revised. Moreover, the 1st picture data and the 2nd and succeeding picture data are fed to a differential detection circuit 65 for a period when each picture data by pickup is applied and the circuit 65 obtains a difference data between relevant picture elements. Then the data is stored in a high speed storage memory circuit 7 without recording of a tape while the recording speed is slow during the consecutive shot. Then the difference data is decoded at the end of the consecutive shot and recorded on a magnetic tape. Thus, the restriction of the consecutive shot due to a slow recording speed is released.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a recording device for recording various information signals such as video signals on a recording medium such as a magnetic tape.

[Prior art 1] Conventionally, it has been generally known that various digital signals such as video signals and audio signals are recorded on a magnetic tape housed in a small cassette. The information signal is transmitted to a transmission system within the device at a predetermined transmission rate and subjected to processing such as signal processing and recording/reproduction.

[Problems to be Solved by the Invention] Incidentally, it is desirable that the signal transmission speed in the above magnetic recording/reproducing device be low in relation to the processing speed of various signals. However, if the transmission speed is reduced, the time required for recording becomes longer when recording a video signal with a large amount of information.

In other words, the transmission speed is 76, which is sufficient for transmitting audio signals.
8Kbit/sec (=2 (ch) x 32 (K
If you set about Hz)
It takes about 4.8 seconds to record a video signal of t (=640×480×12 (bits)).

Therefore, when the above-mentioned magnetic recording and reproducing device is used as an electronic still camera, the recording time for one frame is long, which limits the shutter timing and slows down the continuous shooting speed. It will be subject to functional restrictions.

[Means for Solving the Problems 1] The present invention has been made in view of the above-mentioned circumstances, and provides a recording and/or reproducing device that can eliminate restrictions on continuous shooting speed caused by slow transmission speed. The purpose is to

In order to achieve this object, the present invention provides a recording device for recording each image data of a plurality of screens continuously obtained within a predetermined period, the present invention comprising a first recording device for storing each of the above image data.
storage means, second storage means for storing the image data transferred from the first storage means, and control means for controlling the transfer of the image data to these storage means,
The image data stored in the first storage means includes difference data from the previous screen, and the original image data restored from the difference data is stored in the first storage means at a slower speed than the recording speed in the first storage means. The present invention provides a recording device characterized in that data is transferred to a second storage means.

[Function] According to the present invention as described above, the image data obtained by snapshotting is temporarily stored in the first storage means, and later transferred to the second storage means at a low speed, thereby making it possible to reduce the speed of continuous recording due to the recording speed. Since restrictions on the shooting speed can be removed, it is possible to improve the continuous shooting speed.

Further, according to the present invention, the storage capacity of the first storage means can be saved by compressing the data amount of the second and subsequent images during continuous shooting while maintaining the difference.

Further, in the present invention, when storing each image data in the second storage means, by storing each image data in a restored state, even a playback device without a restoration function can store the image data from the storage medium in the second storage means. Can be played.

[Embodiment 1] Hereinafter, a preferred embodiment according to the present invention will be described in detail with reference to FIGS. 1 to 4.

FIG. 1 is a block diagram showing the configuration of one embodiment of a magnetic recording device according to the present invention. In this embodiment, digitization is performed on a magnetic tape housed in a small cassette as shown in FIG. Video signals, audio signals, etc. are selectively magnetically recorded on each track, which will be described later.

The cassette C stores a magnetic tape Tp wound between a pair of tape reels disposed inside the cassette body as shown in FIG. It is supposed to be desired externally through. Further, a magnetic recording section 2 is formed on the side surface of this cassette C, and as described later, index information regarding the amount of recording recorded on the magnetic tape, etc. is recorded in this recording section 2. .

On the other hand, in this embodiment in which the magnetic tape in the cassette C as described above is used as the recording medium, the imaging light from the subject is passed through the optical system 3 having an aperture mechanism, an autofocus mechanism, etc. to a CCD (charge coupled device), etc. The resulting video signal is amplified by a predetermined amount in a preamplifier (not shown) and then sent to an A/D converter.
The (analog/digital) converter 5 converts the signal into a digital signal with a predetermined number of bits. Note that the sampling frequency of this A/D converter 5 in this embodiment is 32 KHz, and the quantization bits are 8 bits.

Further, an audio signal is supplied to this A/D converter 5 via an input terminal 15.

These digitized image data and the like are supplied to the digital signal processing device 6.

Here, the digital signal processing device 6 includes first to third switch circuits 61, 62, 63, and a digital signal processing circuit 64 that performs predetermined signal processing on the output of the second switch circuit 62. A difference detection circuit 65 and a synthesis circuit 66 that detect a difference between two consecutive images during continuous shooting.
The switching circuits 61, 62, and 63 are controlled by a system controller 13, which will be described later, depending on the shooting mode (continuous shooting mode or single shooting mode) or whether continuous shooting is in progress.

That is, in this embodiment, in the single shooting mode, the movable contacts of the first and second switch circuits 61 and 62 are set as shown by the solid lines in the figure, so that the A
The output of the /D converter 5 is output after being subjected to predetermined processing in the digital signal processing circuit 63.

On the other hand, in the snapshot mode, each of the switch circuits 61
．． 62 is set as shown by the dotted line in the figure,
The output of the first switch circuit 61 is supplied to the memory circuit 7, and the second switch circuit 62 is supplied with read data from the memory circuit 7.

Further, in the continuous shooting mode, the third switch circuit 63 is switched depending on whether continuous shooting is in progress (photographing) or recording on a magnetic tape after continuous shooting is in progress. The output from the memory circuit 7, which will be described later, is supplied to the difference detection circuit 65, and after continuous shooting, is supplied to the synthesis circuit 66.

The above memory circuit includes two data areas M r and M 2 having a storage capacity of at least one frame, a memory section 71 having a plurality of address data areas MA and differential data MD, a memory control circuit 72, a discrimination circuit 73, and an address. It is configured to include an adder 74 and a data switch circuit 75, and memory control in the memory section 71 and address data generated in the address adder 74 are controlled by the memory control circuit 72. .

Furthermore, the address data area MA and the differential data MD
are combined in pairs, and address designation data and difference data indicating the presence or absence of difference data are respectively stored for each pixel of the second and subsequent images during continuous shooting.

The operation of the memory circuit 7 having such a configuration is such that during continuous shooting, the first image data is supplied to the data area M1, and the second and subsequent image data are sequentially supplied to the other data area M2. updated and stored.

Further, during a period while each piece of image data obtained by photography is being supplied, difference data between the first image data and the second and subsequent image data is obtained. That is, the data area M
1, the first image data stored in M* and n
The image data of the th image (n is 2 or more) is read out and controlled for each pixel by the memory control circuit 72 and supplied to the difference detection circuit 65 via the third switch circuit 63 of the digital processing device 6. Then, difference data between corresponding pixels in each data is determined. This differential data is
Only those with difference data are stored in the predetermined difference data area M0 with the pixel address supplied from the address adder 74 added, and
The signal is supplied to the discrimination circuit 73 described above.

This discrimination circuit 73 discriminates the presence or absence of supplied differential data on a pixel-by-pixel basis.
0'' is stored in each address of the address data area MA configured in the address table.

Note that the discrimination output of this discrimination circuit 73 is also supplied to the memory control circuit 72, and only when there is differential data corresponding to a pixel whose discrimination output is "1", that is, differential data, the differential data area MD of the differential data is Allow writing to.

Thereafter, this process is repeated for each image data, and during quick shooting, the difference data between each screen obtained by this quick shooting and the first screen is sequentially stored in each of the data areas M A and M o. To go.

On the other hand, when recording on a magnetic tape after continuous shooting, the first image data stored in the data area M1,
The magnetic tape Tp is in a state where the image data of the second and subsequent sheets is restored by the address copy data and the difference data stored in the address data area MA and the difference data area M0.
recorded in

In other words, when recording on tape after continuous shooting, the first
The image data for the first image is read out from the data area M1 and supplied to the digital processing circuit 64 via the second switch circuit 62 of the digital processing device 6, where it is subjected to predetermined signal processing and then to the recording/reproducing unit. 8.

Furthermore, in order to restore the differential data for the second and subsequent images, the first image data stored in the data area M+ is supplied to the synthesis circuit 66 pixel by pixel via the third switch circuit 63, and The differential data stored in the differential data area Mo is supplied to the synthesizing circuit 66, and the synthesizing circuit 66 synthesizes the data to create another data area M2.
is stored at the corresponding pixel address.

Here, the address control circuit 72 reads addressing data from the address data area MA and controls switching of the data switch 75 in accordance with this data. That is, when the addressing data is "0", the data switch 75 is set as shown by the solid line in the figure and supplies the image data read from the data area M1 to the other data area M2. and is stored at the corresponding pixel address, and is switched only when the addressing data is "1" to supply the composite output of the composite circuit 66 to the data area M2.

As a result, the data area M2 contains image data obtained by combining difference data only for pixels that have differences from the first image data, that is, restored image data. The n-th image data is stored, and this image data is supplied to the digital processing circuit 64 via the second switch circuit 62.

Note that the synthesis circuit 66 is reset in synchronization with the pixel supply timing.

The image data outputted from the digital processing circuit 6 is supplied to a recording/reproducing section 8, where it is recorded on a magnetic tape in a cassette mounted in a cassette mounting section 9.

Here, as shown in FIG. 3, the recording/reproducing section 8 includes two rotary heads Hel for recording/reproducing video signals and the like on the magnetic tape Tp.

The rotating drum 10 is equipped with a rotating drum 10 having He2, and when the cassette is installed in the cassette mounting section of the recording/reproducing section 9, the rotating drum 10 moves inside the cassette C as shown by the solid line in FIG. , is pressed against the magnetic tape guided by tape guides 11 and 12 at the front of the cassette.

As a result, in this embodiment, approximately 100 yen is attached to the outer periphery of the rotating drum 10 without loading the magnetic tape.
It can be wrapped over an angular range of 0.000.

Further, the rotating drum 10 is inclined at a predetermined angle with respect to the longitudinal direction of the magnetic tape, and by rotating the rotating drum 1o and running the magnetic tape by a reel driving means (not shown), an image is recorded on the magnetic tape. Signals, audio signals, photographic information (index signals) to be described later, etc. are recorded diagonally as shown in FIG. Note that the reel driving means applies a predetermined load to the reel, so that contact pressure between the magnetic tape and the rotary head can be obtained.

Furthermore, the recording/reproducing section 8 is equipped with a magnetic head He3 for recording index information on the magnetic recording section 2 formed on the side surface of the cassette C, and this magnetic head is used to record index information on the magnetic recording section 2 formed on the side surface of the cassette C. It comes into contact with the magnetic recording section 2 as it is attached. This magnetic head He3 also includes a system controller (system controller) 13.
Index information such as the number of recording sheets is supplied from the tape cassette via the information recording section 14, and is recorded in the magnetic recording section 2 of the tape cassette.

The system controller 13 has release switches Sw1 and Sw2.
The above-mentioned optical system 3 and sensor 4 are controlled and the memory circuit 7 is controlled in accordance with the operation of the operation unit 17 having the imaging mode setting switch Sw3 for setting the imaging mode to single shooting mode or continuous shooting mode. Performs system control of the entire device such as read control and mode control.

Next, the recording sequence of this embodiment will be explained using 1.2 in FIG.

In S301, if the first stage of the release switch, that is, SWI, is on, the process advances to 5302. If the continuous shooting mode is set by the shooting mode switch SW3, the process advances to 5308, and if it is the single shooting mode, the process advances to 5303. Each proceed.

In the case of the single shooting mode, in step 5303, if the second stage SW2 of the release switch is on, the sensor 4 is driven after exposure is completed to read out the video signal (step 5304). The read video signal passes through the A/D converter 3, passes through the digital signal processing device 6, and is recorded onto a tape by the recording/reproducing section 8.

On the other hand, in the case of continuous shooting mode, S
When W2 is detected to be on, proceed to 5309 and check which side of continuous shooting is on, and if it is 2 or more screens, go to ■, 1
If it is the screen number, proceed to 5310. In 5310,
After the exposure is completed, the sensor 2 is read out, the video signal is A/D converted (S311), and the digitized image data is stored in the data recording M1 of the memory circuit 7. Next, the ON operation of SW2 is confirmed again (
S313). In 5309, even if there are two or more snapshots, the process proceeds from ① to 5313, so the explanation will be continued from here. If SW2 is on in 5313, 53
At step 14, after the exposure of the next screen is completed, the sensor 4 is read out, A/D conversion is performed (S315), and the digital image data is transferred to another data area M2 of the memory circuit 7.

Next, the image data M1 and M2 data for one screen are compared in pixel units (S317).

M r (a d r ) − M 2 (a d
r ) = ΔM Note that adr is determined by the determination circuit 73 when it is determined that there is a difference ΔM in image data at the pixel address 5318 (when the image changes).
The program proceeds to 5319 and writes "1" in the address table on the address data area MA of the memory circuit 7 as address designation data.

Next, in 5320, the image difference data ΔM is stored in the difference data area Mo on the memory 7 together with the pixel address from the address adder 74.

On the other hand, if there is no image data difference ΔM in 5318 (the image has not changed), the process advances to D321 and the address table on the address data area M^ is written as “
0'' is stored, and the difference data (O in this case) is not stored.

Then, in 5323, if the comparison of all pixels of the image data is not completed, the process returns to 5317 and the comparison is performed. On the other hand, when all pixel comparisons are completed, the process returns to 5313 and the state of SW2 is detected again.

As described above, by repeating this loop while SW2 is on, from the second screen onwards, the difference data from the first screen and the addressing data are stored in the predetermined data areas MD and MA of the memory circuit 7. Import and continue continuous shooting.

In this way, when the continuous shooting operation is repeated several times and SW2 is turned off in 5313, the process advances to 5324 and the image data of the first screen during continuous shooting stored in Ml of the memory circuit 7 is converted into a digital signal. The data is supplied to a processing device 6 and a recording/reproducing section 8, where it is recorded onto a tape 8. Next, if there is addressing data and differential data in the memory circuit 7, 532
Proceed to step 6 to restore the image data as described above. At this time, all at 1 nos (all pixels) is performed by the following method.

As described above, the image data is restored to another data area M2 of the memory circuit 7, read from this data area M2, and recorded on the tape in the same manner. 5 after recording ends
Returning to step 325, this loop of "restoring image data and recording on tape" is repeated to record the entire screen shot. In this way, all the difference data on the memory 7 is restored and recorded on the tape, and the quick copying operation is completed.

In the above-mentioned embodiment, during continuous shooting, data is stored in the memory circuit 7 capable of high-speed recording without performing recording on a magnetic tape, which has a slow recording speed, and the differential data is restored after the continuous shooting operation is completed. Since the recording is performed on a magnetic tape, the restriction on the speed of quick copying due to the slow recording speed can be removed.

In the above-described embodiment, since the image data for the second and subsequent images during continuous shooting is only the difference data with respect to the first screen, the amount of data can be compressed and the time required for recording can be shortened. This makes it possible to increase the continuous shooting speed during quick shooting.

In addition, since the amount of data is compressed, it is possible to use the recording medium efficiently, and this effect is particularly effective when a relatively small-capacity recording medium such as a group memory is used as in this embodiment. Significant in some cases.

Furthermore, in this embodiment, in order to obtain the above-mentioned difference data, the image data for two consecutive screens is once loaded into the memory circuit 7, and the corresponding pixels of each image data are read out synchronously, so that Accurate difference data can be obtained. Further, since pixels for which there is no difference are not recorded in the memory circuit 7, capacity can be saved from this point as well.

In addition, in this embodiment, by storing the address specification data in the memory as described above, it is only necessary to perform the compositing process on the pixels for which there is difference data. The time required for this can be shortened.

[Other Embodiments] In this embodiment, during continuous shooting, there are not so many change points in the image (and there are only a few difference data), so the data is not recorded on the tape but taken into the memory circuit 7. Since the capacity also has a limit, recording onto the tape may be performed when the capacity of the memory circuit 7 is full.

Also, as the number of snapshot frames increases, the difference from the first screen also increases, and if the amount of differential data increases, record it on a tape and update the contents of the data area M1 again. Good too.

Furthermore, if there is sufficient memory capacity, it may be possible to have a plurality of reference image data from which differences are taken.

Further, in this embodiment, a magnetic tape is used as the recording medium, but the recording medium is not limited to this, and may be, for example, a magnetic disk, a magneto-optical disk, or a solid-state memory.

Furthermore, in the above embodiment, in order to obtain the difference data for the second and subsequent screens, the difference from the first screen was always calculated, but even if the difference data from the immediately previous screen was calculated. good.

In that case, since the amount of difference is reduced, the capacity of the difference data area can be reduced.

Further, in the single shooting mode in the above-described embodiment, the image data was recorded without going through the memory circuit 7, but it may be recorded on the magnetic tape after being stored in the memory circuit 7.
In that case, one screen of image data may be sampled and divided into a plurality of blocks, and each block may be recorded sequentially.

[Effect 1 of the Invention As is clear from the above description, according to the present invention, during continuous shooting, the image data of each screen obtained by continuous shooting is temporarily stored in the first recording means, and the image data of each screen obtained by continuous shooting is temporarily stored. By transferring the memory contents of the first storage means to the second storage means at the stage where the continuous shooting speed is completed, it is possible to increase the continuous shooting speed.

Further, when storing the image data in the first storage means, the capacity of the collective memory can be reduced by compressing and recording the image data as differential data.

Furthermore, in the present invention, since the image data is restored and stored when it is stored in the second storage means, even an apparatus that does not have a restoration function can perform the reproduction.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of the recording device according to the present invention, Fig. 2 is a perspective view of a tape cassette, Fig. 3 is a schematic plan view showing the recording/reproducing section, and Fig. 4 is a flowchart showing the recording operation. It is. 4...Sensor 6...Digital signal processing device 7...Memory circuit 8...Recording and reproducing section 9...Tape cassette

Claims (1)

[Scope of Claims] A recording device for recording each image data of a plurality of screens continuously obtained within a predetermined period, comprising: a first storage means for storing each of the image data; and the first storage. A second storage means for storing image data transferred from the storage means, and a control means for controlling the transfer of the image data to these storage means, wherein the image data stored in the first storage means is It includes the difference data from the screen and the original image data restored from these difference data.
A recording device characterized in that the data is transferred to the second storage means at a lower speed than the recording speed to the second storage means.