JP2003009058A - Video camera device and picked-up picture recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a video camera device which easily performs short-time intermittent picture recording without a burden to a recording mechanism for a magnetic tape. SOLUTION: A picture signal picked up by a camera block 2 is supplied to a temporary storage part 5 through a sampling rate conversion part 3 and a video encoder 4. A memory control part 52 stores a picture signal of a prescribed number of frames out of the supplied picture signal in a semiconductor memory 51 on the basis of control of a recording control part 8. When the frequency of this temporary storage to the semiconductor memory 51 reaches a prescribed number, the memory control part 52 reads out the picture signal stored in the semiconductor memory 51 on the basis of a request from the recording control part 8 and transfers it to a tape drive 7 through an RF interface 6. Each time the picture signal is supplied to the tape drive 7, the tape drive 7 runs the magnetic tape to record the picture signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video camera device for recording a captured image signal on a magnetic tape and a captured image recording method.

[0002]

2. Description of the Related Art In recent years, CCD (Charge Coupled Devic
e) A so-called video camera, which is configured by combining a camera and a video tape recorder using a magnetic tape, is widely used for home and business purposes. In such a video camera, an image signal picked up by a CCD camera and an audio signal picked up by a microphone are temporarily recorded on a magnetic tape by a video tape recorder, and later, the recorded image signal and audio are recorded. Signal
It can be played back using the built-in liquid crystal screen, or viewed using an external monitor device such as a television receiver.

Recently, a video camera using a disk-type recording medium such as a hard disk has appeared in place of the magnetic tape. With such a video camera, it is possible to access a desired recording location in a short time without performing fast-forwarding or rewinding unlike the case where a magnetic tape is used. It is suitable for use such as erasing only a new image and recording a new image, or continuously recording an image and selecting an image that is old in time and recording a new image in this recording portion.

[0004]

By the way, in the video camera as described above, it is a usual use method to continuously take images, but for example, it is possible to take an image in a very short time such as every frame. There is a demand for an intermittent function. For example, when shooting an object that moves very slowly, such as flowering of flowers, movement of clouds, changes in dunes, etc., the images taken by the CCD camera are intermittently taken as static images for a long time at regular intervals. By recording and reproducing this recording signal as a continuous image later, it becomes possible to see the motion transition of this object in quick motion. Also, by intermittently recording each frame, it can be used for animation production.

In a conventional video camera using a magnetic tape as a recording medium, if the recording is performed frame by frame in the case of performing such intermittent recording of images, the mechanical parts of the drive system of the magnetic tape or the drum device are used. It is worn out, etc.
Since the mechanical load is large, it is necessary to use highly accurate parts for these parts, and high accuracy is also required for their control. For this reason, conventionally, such a function can be realized only by a stationary video tape recorder for editing broadcast material, and in the case of a video camera that requires high impact resistance and miniaturization, at least four frames are required. Intermittent recording was the limit.

Although a video camera using a disc type recording medium can basically perform intermittent recording one frame at a time, even in this case, for example, the characteristics of the recording medium are vulnerable to shock. However, there are drawbacks such that the recordable time is shorter than the magnetic tape, the cost per recording time is high, and the weight of the apparatus is large.

The present invention has been made in view of the above problems, and a video capable of easily performing intermittent recording of images for a short time without imposing a burden on the recording mechanism of the magnetic tape. An object is to provide a camera device.

Another object of the present invention is to provide a picked-up image recording method capable of easily performing intermittent recording of images for a short time without imposing a load on the recording mechanism on the magnetic tape. That is.

[0009]

According to the present invention, in order to solve the above-mentioned problems, in a video camera device for recording a picked-up image signal on a magnetic tape, an image pickup means for picking up an object and an image signal by the image pickup means are provided. In contrast, a signal conversion unit that performs a predetermined signal conversion process and an image signal output from the signal conversion unit are intermittently stored a plurality of times for each predetermined number of consecutive frames, and the stored image signal is stored. Is provided in sequence, and a tape recording unit for continuously recording the image signal output from the temporary storage unit on the magnetic tape is provided.

In such a video camera device, since the image signal thus picked up is intermittently stored by the temporary storage means by a substantially constant amount, the stored image signal is recorded on the magnetic tape. When recording on magnetic tape,
It is possible to perform intermittent recording of captured image signals without imposing a heavy load on the recording mechanism for the magnetic tape.

Further, according to the present invention, in a picked-up image recording method for recording a picked-up image signal on a magnetic tape,
An image signal obtained by imaging a subject and converting it into an electric signal is intermittently stored by a semiconductor memory for each predetermined number of consecutive frames, and the image signal stored and output by the semiconductor memory for the plurality of times is output. There is provided a picked-up image recording method, which comprises continuously recording on the magnetic tape.

In such a picked-up image recording method, since the picked-up image signal is intermittently stored in the semiconductor memory by a substantially constant amount, the stored image signal is recorded on the magnetic tape. When recording on magnetic tape,
It is possible to perform intermittent recording of captured image signals without imposing a heavy load on the recording mechanism for the magnetic tape.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. First, FIG. 1 shows a schematic configuration example of a video camera device of the present invention. In the following description, H
A video camera device for recording an image signal based on the DTV (High Definition Television) system will be taken as an example.

FIG. 1 shows an example of the configuration of a signal recording system in the video camera device 1 of the present invention. In this video camera device 1, a camera block 2 that images a subject
And a sampling rate converter 3 for converting the output image signal from the camera block 2 into a predetermined sampling rate.
A video encoder 4 that performs signal processing such as predetermined band compression on the output image signal from the sampling rate conversion unit 3; a temporary storage unit 5 that temporarily stores the output signal from the video encoder 4; RF interface 6 for converting the output image signal from the storage unit 5 into an analog signal
And a tape drive 7 for recording an output signal from the RF interface 6 on a magnetic tape (not shown), and a recording controller 8 for controlling the operations of the temporary storage unit 5 and the tape drive 7.

The camera block 2 uses CC as an image pickup device.
A D (Charge Coupled Device) 21 is provided, and a light beam from a subject is received by the CCD 21 and converted into an electrical signal, which has a data rate of 20 bits and 74 MHz.
Convert to digitized data and output. The sampling rate conversion unit 3 converts the image signal from the camera block 2 into a data rate of 20 bits and 46 MHz and outputs it. The video encoder 4 performs a predetermined band compression process on the image signal output from the sampling rate conversion unit 3, converts the image signal into a 16-bit, 46 MHz (140 Mbps) data rate, and outputs the data rate.

The temporary storage unit 5 is a semiconductor memory 5 for temporarily storing the image signal output from the video encoder 4.
1 and writing an image signal to the semiconductor memory 51,
And a memory control unit 52 that controls reading of the stored image signal. The memory control unit 52
Based on the request from the recording control unit 8, a predetermined number of frames of image signals from the image signals from the video encoder 4 are transferred to and stored in the semiconductor memory 51. Such an image signal storage operation is intermittently performed by receiving a request from the recording control unit 8 at regular intervals. The semiconductor memory 51 has a sufficient capacity to store image data which is intermittently transferred a plurality of times. Further, the memory control unit 52 reads the image signal accumulated in the semiconductor memory 51 based on the request from the recording control unit 8 and outputs it to the RF interface 6.

The RF interface 6 converts the image signal output from the temporary storage unit 5 into a form suitable for recording on a magnetic tape and outputs it. The tape drive 7 has, for example, a rotary drum equipped with a magnetic head for recording a signal on the magnetic tape, a magnetic tape running mechanism for running around the rotary drum, and the like. The output image signal is recorded on the magnetic tape.

The recording control unit 8 is composed of, for example, a microprocessor or the like, and outputs a control signal for requesting a write operation and a read operation of the image signal in the temporary storage unit 5 with respect to the semiconductor memory 51, thereby operating in the temporary storage unit 5. To control. At the same time, the signal recording operation on the magnetic tape in the tape drive 7 is controlled. Specifically, in the temporary storage unit 5, each time the image signal stored in the semiconductor memory 51 is output, the tape drive 7 is operated to continuously transfer the image signal input via the RF interface 6 to the magnetic tape. To record.

In the video camera device 1, when the normal use method of continuously recording the picked-up image signals on the magnetic tape is continuously performed, the image signals output from the video encoder 4 are temporarily stored in the temporary storage section 5. Is output to the RF interface 6 as it is, and is continuously recorded on the magnetic tape running at a constant speed in the tape drive 7.

Here, FIG. 2 schematically shows an image signal in the intermittent recording operation as a data structure of a video frame in real time. 2A shows a picked-up image signal, FIG. 2B shows an image signal stored in the semiconductor memory 51, and FIG. 2C shows an image signal recorded on a magnetic tape. Note that in FIG. 2, the block element of one frame represents one frame.

The image signal shown in FIG. 2A is an image signal output from the video encoder 4 and is temporally continuous data captured by the camera block 2. Such a temporally continuous image signal is transferred to the semiconductor memory 51 by the memory control unit 52 of the temporary storage unit 5 at a predetermined time interval by a predetermined number of frames. The memory control unit 52 receives, from the recording control unit 8, for example, a control signal indicating a storage timing of an image signal in the semiconductor memory 51 at regular time intervals, and when the control signal is received, an image signal having a preset number of frames is output to the semiconductor signal. Transfer to the memory 51. As a result, intermittent image signals are accumulated in the semiconductor memory 51 as shown in FIG. In the example of FIG. 2, from the picked-up image signal, the image signal for 2 frames is obtained every 8 frames.
It is stored in 1.

Next, when a predetermined amount of image signals are stored in the semiconductor memory 51, the memory control unit 52 responds to the control signal from the recording control unit 8 and outputs the image signals of the stored amount from the semiconductor memory 51. It is read and transferred to the tape drive 7 via the RF interface 6. In the tape drive 7, under the control of the recording control unit 8, as shown in FIG.
The supplied image signal is continuously recorded on the magnetic tape as shown in FIG. For example, in the case of FIG. 2, when the image signals for 6 frames are accumulated in the semiconductor memory 51, they are transferred to the tape drive 7.

In the conventional video camera device, in order to perform such an intermittent recording with a very small number of frames, as shown in FIG. 2A, the images captured by the camera block 2 and continuously input. Since the signal was recorded on the magnetic tape every predetermined time,
The load on the magnetic tape itself, or the drive mechanism for running the magnetic tape, rotating the rotating drum, etc. is large,
Further, due to such a burden on the driving mechanism and the difficulty of control, it is only possible to record at least four frames at a time. In the video camera device 1 of the present invention, the image signal intermittently extracted from the captured image signal is temporarily stored in the semiconductor memory 51, and when the predetermined amount is accumulated, the accumulated image signal is recorded on the magnetic tape. Therefore, in the tape drive 7, the number of times the drive mechanism is repeatedly started and ended is reduced to reduce the load on the drive mechanism, and by using the semiconductor memory 51, the drive mechanism at the time of recording has a higher accuracy. Intermittent recording can be easily performed for each very small number of frames, such as one frame, without performing control.

In the video camera device 1 described above, in consideration of the load on the drive mechanism in the magnetic tape or the tape drive 7 described above, the semiconductor memory 51 has 4 units.
It suffices that the image signal of a frame or more is temporarily stored, and thus the minimum storage capacity required for the semiconductor memory 51 is determined. However, the semiconductor memory 51
The larger the storage capacity of the semiconductor memory 51, the smaller the number of operations of the drive mechanism in the tape drive 7 and the less the consumption of the components. Therefore, the larger the storage capacity of the semiconductor memory 51 is.

For example, when an image signal based on the HDTV system is band-compressed in the video encoder 4, the semiconductor memory 51 has an SDRAM (Synchronous Dynamic Random Access Mem) having a storage capacity of 128 Mbytes.
It is possible to store an image signal for about 7 seconds (224 frames) by using eight mory). In this case, when the image signals for 224 frames are accumulated in the semiconductor memory 51, the image signals can be recorded on the magnetic tape by running the magnetic tape for about 7 seconds. When the image signal for one frame is set to be stored by one time of temporary storage for, the recording on the magnetic tape is performed once for every 224 intermittent recordings.

In the video camera device 1 described above, the semiconductor memory 51 is used to temporarily store the image signal in the temporary storage unit 5. However, the writing operation and the reading operation are performed at high speed, and a very small amount of data is stored. The recording medium is not limited to this as long as it is a recording medium in which accurate writing can be easily performed. For example, a hard disk device may be used. However, since the video camera device 1 is carried around and used, it is desirable to use the semiconductor memory 51 that does not include a drive mechanism portion and is relatively light in weight.

Next, FIG. 3 shows a flowchart of processing in the recording control unit 8 when performing intermittent recording. Step S
At 301, an intermittent recording operation is initialized based on a control signal from an operation input unit (not shown). As the initial setting, for example, an operation such as the number of frames per one time at the time of intermittent temporary storage in the semiconductor memory 51, automatic storage in the semiconductor memory 51, or manual operation The mode is set. The setting information of the number of frames in the temporary storage in the semiconductor memory 51 is stored in the memory control unit 52 in the temporary storage unit 5.
Sent to. Further, in the operation mode setting, for example, when intermittent temporary storage is automatically performed in the semiconductor memory 51, if the total time for imaging a subject and the recording time on the magnetic tape are set, the semiconductor memory is set. The interval of temporary storage for 51 may be automatically calculated so that temporary storage is performed at regular intervals.

In step S302, the intermittent recording operation is started, a control signal is sent to the temporary storage section 5, and the image signal output from the video encoder 4 is
A request is made to write a predetermined number of frames of image signals in the semiconductor memory 51. When the operation mode in which the temporary storage in the semiconductor memory 51 is performed manually is set, the REC start button provided in the video camera device 1 or an operation input by the user using an external remote control switch or the like is used. Based on this, the control signal is transmitted. When an operation mode for automatically performing temporary storage is set, time calculation is performed and a control signal is sent when the set time has elapsed. At this time, counting of the number of requests for temporary storage is started.

In step S303, it is determined whether or not the number of times the semiconductor memory 51 is requested for temporary storage has reached a predetermined number. If the number has not reached the predetermined number, the process returns to step S302, and the temporary storage section 5 is stored. On the other hand, the next temporary storage is requested, and if it is reached, the process proceeds to step S304. In step S304, a control signal is sent to the temporary storage unit 5, and the image signal stored in the semiconductor memory 51 is read out and requested to be transferred to the tape drive 7 through the RF interface 6. In step S305, a control signal is sent to the tape drive 7 to start running of the magnetic tape, and a request is made to record the image signal supplied through the RF interface 6 on the magnetic tape. As a result, the image signal accumulated in the semiconductor memory 51 by a plurality of temporary storages is recorded on the magnetic tape. At this time, in the tape drive 7, the supplied image signal is continuously recorded in the area immediately after the image signal of the previous recording on the magnetic tape.

In step S306, it is determined whether or not all the image signals stored in the semiconductor memory 51 have been read out. If the image signals are being read out, step S3 is performed.
Returning to 04, the reading of the image signal and the recording on the magnetic tape are continued, and when the reading is completed, the process proceeds to step S307. Completion of data reading from the semiconductor memory 51 is determined by receiving a control signal from the memory control unit 52, for example. Further, the memory control unit 52 determines the end of reading from the semiconductor memory 51 by counting the read address in the semiconductor memory 51, and automatically stops the read operation. In step S307, the tape drive 7
A control signal is sent to the device to request that the running of the magnetic tape be stopped and the recording operation of the image signal on the magnetic tape be stopped. In step S308, it is determined whether or not the intermittent recording operation is to be ended. If it is not ended, the process returns to step S302, the next temporary storage is requested to the temporary storage unit 5, and if it is determined to be ended, the intermittent recording operation is stopped. The recording operation ends. This determination is made by, for example, the semiconductor memory 51.
If the operation mode in which temporary storage is manually performed is set, it is performed based on the operation input by the user, and if the operation mode in which temporary storage is automatically set is set, the time is calculated. This is performed by determining whether or not the imaging time set by is passed.

In the above process, step S303.
In the above, the timing of reading the image signal from the semiconductor memory 51 is determined based on the number of times of temporary storage in the semiconductor memory 51.
The image signal may be read when the data amount of the image signal stored in 1 exceeds a predetermined amount. In step S304, the semiconductor memory 5
Even when the timing of temporary storage comes while the image signal is being read from 1, the image signal of a predetermined number of frames is written to the semiconductor memory 51 in parallel with the reading of the image signal. You may do it.

In the above video camera device 1, the conventional video camera device is combined with the semiconductor memory 51, so that the magnetic tape and the drive system of the tape drive 7 are not burdened with a large load and are intermittently operated. It becomes possible to record an image. This video camera device 1
Then, for example, by recording a very slow-moving subject such as flowering of flowers, movement of clouds, or change of sand dunes every few frames, such as one frame, with time, the movement of the subject over a long period of time can be recorded. It is possible to record the change in the image as a recorded image in a short time. Further, by storing one frame or several frames for one scene in the semiconductor memory 51 and continuously recording this image signal on a magnetic tape, animation can be easily produced.

In addition, such a small number of intermittent recordings for each frame can be performed by using a disk type recording medium in the past, but in the present invention, a magnetic tape which is a relatively inexpensive recording medium is used. Since the image signal is recorded by using it, the intermittent recording can be performed at low cost.

Finally, FIG. 4 shows a concrete configuration example of the temporary storage unit 5. In the temporary storage unit 5 shown in FIG. 4, an SDRAM is used as the semiconductor memory 51 for temporarily storing the image signal.
51a is used. Further, the memory control unit 52 uses the SD
A writing / reading control unit (hereinafter abbreviated as W / R control unit) 52a which controls writing / reading of signals to / from the RAM 51a and sends / receives image data.
And the image signal output from the video encoder 4 is SD
A signal converter 52b for converting the data format to be stored in the RAM 51a, a signal converter 52c for converting the image signal from the SDRAM 51a into the original data format, and SD
A write address issuing unit (hereinafter abbreviated as W address issuing unit) 52d and a read address issuing unit (hereinafter abbreviated as R address issuing unit) 52e that issue a write address and a read address of data in the RAM 51a, and data in the SDRAM 51a. The timing control unit 52f controls the read timing and the write timing. These components of the temporary storage unit 5 are usually formed on the same substrate.

The W / R control unit 52a receives the designation of the write address from the W address issuing unit 52d, and based on the timing designation by the trigger signal supplied from the timing control unit 52f, sends the image signal from the signal conversion unit 52b. , SDRAM 51a to the designated address area. Similarly, the timing control unit 5 receives the designation of the read address from the R address issuing unit 52c.
Based on the timing specified by the trigger signal from 2f,
The image signal stored in the designated address area of the SDRAM 51a is read and output to the signal conversion unit 52c. The W address issuing unit 52d and the R address issuing unit 52e both include a counter for outputting a designated value of the address, and count up while the trigger signal supplied from the timing control unit 52f to each is at the H level. And outputs the count value to the W / R control unit 52a. The timing control unit 52f outputs write and read trigger signals based on the control signal supplied from the recording control unit 8, and the SDRAM 51a.
Controls the timing of writing and reading data to and from.

In the timing controller 52f, W /
The rising and falling edges of the trigger signal are latched at the rising edge of the frame synchronization signal of the image signal supplied to the R control unit 52a, thereby specifying the number of frames of the image signal according to the H level time of the trigger signal. It
That is, the W address issuing unit 52d sequentially issues the write address only while the image signal of the predetermined number of frames is supplied to the W / R control unit 52a.
In the R address issuing unit 52e, the read addresses are sequentially issued only while the image signals of the designated number of frames are read from the SDRAM 51a. Such SDR
By controlling the write address and the read address with respect to the AM 51a, it is possible to perform accurate writing and reading with respect to the image signal of the designated frame number.

[0037]

As described above, in the video camera device of the present invention, the captured image signal is intermittently stored by the temporary storage means by a substantially constant amount, and then the stored image signal is stored. Since the data is recorded on the magnetic tape, it is possible to perform the intermittent recording of the picked-up image signal without giving a heavy load to the recording mechanism for the magnetic tape when recording on the magnetic tape.

Further, in the picked-up image recording method of the present invention, the picked-up image signal is intermittently stored in the semiconductor memory by a substantially constant amount, and then the stored image signal is recorded on the magnetic tape. Therefore, when recording on a magnetic tape, it is possible to perform intermittent recording of a captured image signal without imposing a heavy load on the recording mechanism for the magnetic tape.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration example of a video camera device of the present invention.

FIG. 2 is a diagram schematically showing an image signal in an intermittent recording operation as a data structure of a video frame in real time, FIG. 2A shows a captured image signal,
(B) shows an image signal stored in the semiconductor memory,
(C) shows an image signal recorded on the magnetic tape.

FIG. 3 is a flowchart showing processing in a recording control unit when performing intermittent recording.

FIG. 4 is a diagram showing a configuration example of a temporary storage unit.

[Explanation of symbols]

1 ... video camera device, 2 ... camera block, 3 ...
... Sampling rate conversion unit, 4 ... Video encoder, 5 ... Temporary storage unit, 6 ... RF interface, 7
...... Tape drive, 8 ...... Record control unit, 21 ...... CC
D, 51 ... Semiconductor memory, 52 ... Memory control unit

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 5C018 FA01 FB02 HA02 HA03                 5C022 AB00 AC69 AC79                 5C053 FA21 FA30 GA20 GB40 KA04                       LA01

Claims (6)

[Claims] 1. A video camera apparatus for recording a picked-up image signal on a magnetic tape, an image pickup unit for picking up an image of a subject, a signal conversion unit for performing a predetermined signal conversion process on the image signal by the image pickup unit, The image signal output from the signal conversion unit is stored a plurality of times intermittently for each predetermined number of consecutive frames, and then the temporarily stored image signal is sequentially output, and the temporary storage unit outputs the image signal. A tape recording unit that continuously records the generated image signal on the magnetic tape. 2. The video camera device according to claim 1, wherein the temporary storage means is a semiconductor memory. 3. The temporary storage means, when intermittently storing the image signals of the predetermined number of frames for a predetermined number of times, sequentially outputs the image signals stored within the predetermined number of times. The video camera device according to claim 1, wherein 4. The video camera device according to claim 1, wherein the temporary storage means is capable of storing the image signal output from the signal conversion means intermittently frame by frame. 5. A first counter that counts up while an image signal of a predetermined number of frames in the image signal output from the signal conversion means is supplied, and an image signal stored in the temporary storage means. A second counter which counts up during sequential reading, and a writing address and reading of the image signal to and from the temporary storage means based on the count values respectively output from the first and second counters. 2. The video camera device according to claim 1, wherein the writing operation and the reading operation are performed by designating the respective addresses. 6. A picked-up image recording method for recording a picked-up image signal on a magnetic tape, wherein the image signal obtained by picking up an image of a subject and converting it into an electric signal is intermittently stored by a semiconductor memory every predetermined number of frames. Then, the image signal recorded and output by the semiconductor memory for the plurality of times is continuously recorded on the magnetic tape.