JP2003153177A - Device and method for image video recording - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain image quality needed to accomplish a video recording target while reducing capacity for data storage concerning technique for performing video recording of images photographed by a monitoring camera. SOLUTION: An image video recorder 20 inputs images photographed by a camera 21. A converting and storing part 202 stores the inputted video recorded data in a first hard disk 211 at a high frame rate. At one hour later, the converting and storing part 202 lowers the frame rate of the stored video recorded data and then stores the video recorded data in the first hard disk 211 again. The frame rate is lowered over a plurality of times with the lapse of time in this way, and video recorded data that are finally at the lowest frame rate are subsequently stored in a second hard disk 212 for long-term storage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for recording and accumulating camera images taken for surveillance purposes.

[0002]

[Technical background] When recording video taken by a surveillance camera, one piece is required to reduce the frequency of exchanging recording media and the storage space occupancy during long-term storage, and simply to reduce the cost of recording media. It is required that long-time recording can be performed for the recording media of. Until now, a long recording time has been realized by thinning out the number of recording frames to one frame per second.

Further, in recent digital recording, in addition to frame thinning, the compression rate is increased and the image size is reduced (rough resolution) to sacrifice the deterioration of the image to realize long-time recording.

[0004]

However, in consideration of the fact that the recording of the video is for surveillance purposes and the evidence video needs to be left when some problem occurs, the full video without skipping frames is taken into consideration. There is also a request to record it neatly. Similarly, since an image with a high compression rate has poor reproducibility, there is a demand to record an image with a low compression rate in order to use it as an evidence video. Regarding the resolution, there is also a demand for leaving a video with a resolution as high as possible.

In other words, it is desired to satisfy the contradictory requirements that the data should be small in order to suppress the media capacity and that the video with a large data capacity is necessary to see the video with high accuracy. is there.

In view of the above problems, it is an object of the present invention to provide a technique for maintaining the quality of an image for achieving the purpose of recorded video while suppressing the volume of recorded data for storage. To do.

[0007]

In order to solve the above-mentioned problems, the invention according to claim 1 is a device for recording a video image taken by a photographing device, wherein a frame rate of recorded data,
The data size can be changed by converting at least one of the compression rate and the resolution, and the image input means for inputting the image captured by the image capturing device is compared with the image input by the image input means. Means for storing the recorded data in the storage device as a large recorded data size, and for the recorded data stored in the storage device for a predetermined time, a conversion process for reducing the data size of the recorded data is performed. Means for storing the converted recording data in the storage device as new recording data in place of the original recording data.

According to a second aspect of the present invention, there is provided a device for recording a video image taken by a photographing device, wherein the data size is changed by converting at least one of a frame rate, a compression rate and a resolution of the recorded data. And a video input unit for inputting a video image captured by the image capturing device, and an initial data storage unit for storing the video image input by the video input unit in the storage device as recorded data having a relatively large data size. A plurality of conversion timings having different elapsed times from the time when the recording data is stored in the initial data storage means are defined, and the recording data whose recording timing has passed each conversion data has a smaller data size. In addition to performing the conversion process, replace the original recorded data with the converted recorded data as new recorded data. A conversion storage means for storing in a storage device, characterized in that it comprises a.

According to a third aspect of the present invention, in the video recording apparatus according to the second aspect, the conversion storage means converts the conversion storage means at a final conversion timing having the longest elapsed time among the conversion timings. A means for storing the recorded data after the storage in a long-term storage device is provided.

According to a fourth aspect of the present invention, in the video recording apparatus according to the second or third aspect, the specific time zone in the video recording data stored in the storage device is specified. Means to add specified information to specify,
The conversion storage means further adds the designation information to the time zone designated by the designation information in the recorded data without lowering the frame rate even after the conversion timing has elapsed. And a means for maintaining the frame rate in the event of a failure.

According to a fifth aspect of the present invention, there is provided a device for recording a video image taken by a photographing device, wherein the data size is changed by converting at least one of a frame rate, a compression rate and a resolution of the recorded data. And an image input unit for inputting an image captured by the image capturing device, and a unit for storing the image input by the image input unit in a storage device as a plurality of recording data having different data sizes. Is characterized by.

According to a sixth aspect of the present invention, in the video recording apparatus according to the fifth aspect, for a plurality of recorded data having different data sizes, the deletion time from the time when each is stored in the storage device. It is specified that each deletion time is shorter as the recorded data having a larger data size, and the recorded data having the smallest data size is stored for a long time without being deleted.

According to a seventh aspect of the present invention, there is provided a method for applying to a video recording device for recording a video image taken by a shooting device, wherein the video recording device is at least one of a frame rate, a compression rate and a resolution of recorded data. A data input step in which the data size can be changed by converting one, and an image captured by the image capturing device is input;
The step of storing in the storage device the video input in the video input step as the video data having a relatively large data size, and the step of storing the video data stored in the storage device for a predetermined time, Performing conversion processing for reducing the data size, and storing the converted recording data as new recording data in the storage device instead of the original recording data.

The present invention according to claim 8 is a method applied to a video recording device for recording a video image taken by an imaging device, wherein the video recording device is at least one of a frame rate, a compression rate and a resolution of recorded data. A data input step in which the data size can be changed by converting one, and an image captured by the image capturing device is input;
An initial data storage step of storing the video input in the video input step as recording data having a relatively large data size in a storage device, and a plurality of conversions with different elapsed times from the time when the recording data is stored in the initial data storage step. The timing is specified, and the recording data that has passed each conversion timing is subjected to conversion processing to reduce the data size of the recording data, and the converted recording data is replaced with the original recording data. And a conversion storing step of storing in the storage device as new recording data.

According to a ninth aspect of the present invention, there is provided a method applied to a video recording apparatus for recording a video image captured by a photographing apparatus, wherein the video recording apparatus is at least one of a frame rate, a compression rate and a resolution of recorded data. A data input step in which the data size can be changed by converting one, and an image captured by the image capturing device is input;
Storing the video input in the video input step in a storage device as a plurality of recorded data having different data sizes.

According to a tenth aspect of the present invention, in the video recording method according to the ninth aspect, for a plurality of recorded data having different data sizes, the deletion time from the time of being stored in the storage device, respectively. It is stipulated that each deletion time is defined shorter for recorded data with a larger data size, and recorded data with the smallest data size is
It is characterized by being stored for a long time without being deleted.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings, taking a hard disk recorder as an example capable of reproducing a surveillance video while recording it.

{Embodiment} <1. System and Device Configuration> FIG. 1 is an overall schematic view of a surveillance system including a video recording device 20 according to an embodiment of the present invention. The monitoring area 1 is an area monitored by the camera 21. The monitoring area 1 can be, for example, inside a building, in an elevator, in a parking lot, or the like.

The camera 21 installed in the surveillance area 1
Is connected to the video recording device 20 via a communication cable. The video recording device 20 includes a camera 21 and a monitor 22.
Etc., and is installed in the security room 2.

FIG. 2 is a diagram showing a functional block configuration of the video recording apparatus 20. The video recording device 20 has an input IF2.
01, and can input a video image captured by the camera 21 via the input IF 201.

The conversion storage unit 202 performs a predetermined data conversion process on a video image input from the camera 21 via the input IF 201, and records the video data after the data conversion process as a first data.
Hard disk 211 or second hard disk 212
To store. The predetermined data conversion process is a conversion process intended to reduce the data size of recorded data, and in the present embodiment, A) conversion of frame rate B) conversion of compression ratio C) resolution One of the conversions is to be performed.

FIG. 3 is a diagram showing a functional block configuration of the conversion storage unit 202. The conversion storage unit 202 has the above A) to
A frame rate conversion unit 31, a compression ratio conversion unit 32, and a resolution conversion unit 33 corresponding to the data conversion processing of C) are provided. In the video recording device 20 of the present embodiment, by switching these conversion processes, video recording using the corresponding conversion process is possible. However, it is also possible to use these conversion processes in combination. In addition, the configuration may be such that any one of the conversion processes is provided independently.

Here, the processing of the conversion storage unit 202 is broadly classified into the following three processings.

1) A process of storing initial data. That is,
The video input from the camera 21 via the input IF 201 is subjected to any of the above data conversion processes A) to C), and the recorded data having a relatively large data size is stored in the first hard disk 211 as initial recorded data. To do.
In addition, as a video with a relatively large data size, a full image that does not perform frame thinning on the input video,
A non-compressed image that does not undergo conversion processing may be used.

2) When the conversion timing, which will be described later, has passed, the recorded data stored in the first hard disk 211 is taken out, and the data conversion processing of any one of A) to C) above is performed to obtain the data size of the recorded data. Is reduced, and the recorded data after conversion is again recorded on the first hard disk 21.
Store in 1.

3) When the final conversion timing elapses, the recording data stored in the first hard disk 211 is taken out, and the data conversion processing of any one of A) to C) above is applied to the data of the recording data. The size is reduced and the converted recording data is stored in the second hard disk 211 for long-term storage.

The image display section 204 outputs the image captured by the camera 21 input through the input IF 201 to the monitor 22. As a result, the surveillance staff waiting in the security room 2 can refer to the video imaged by the camera 21 in real time.

The video display unit 204 also has a function of playing back the recorded data stored in the first hard disk 211 and the second hard disk 212 and outputting the played video to the monitor 22. This allows the observer to
It is possible to arbitrarily select and reproduce and display a past image captured by the camera 21.

The operation unit 23 is for inputting various instructions to the video recording device 20, and a monitor operates the operation unit 23 to switch the image to be reproduced and displayed on the monitor 22 or to display the image. If there is a scene to be noted during confirmation, it is possible to input an instruction to add a mark to the portion.

When a command to add a mark is input from the operation unit 23, the mark adding unit 205 causes the recording data stored in the first hard disk 211 or the second hard disk 212 to be recorded. Designation information (mark) that designates a specific time zone of data is added.

<2. Conversion Timing and Conversion Process> Next,
The timing at which the conversion storage unit 202 performs the recording data conversion process and the contents of the conversion process will be described. Here, of the conversion processing, the frame rate conversion processing will be described as a representative.

As described above, in video recording for surveillance purposes, there is a contradiction that data is reduced to save hard disk capacity and accurate data is required to secure reliability as an evidence video. It has two sides. In the present embodiment, frame rate conversion that solves this problem is performed.

Table 1 is a diagram showing an example of the contents of the conversion timing data 301 stored in the conversion timing storage unit 30 (shown in FIG. 3) included in the conversion storage unit 202.

[0034]

[Table 1]

The conversion timing data 301 indicates the timing for converting the frame rate of the recorded data and the contents of the frame rate at each conversion process.

In the example shown in Table 1, recorded data is stored at a relatively high frame rate of 30 fps at the initial storage. In other words, in this example, recording is performed in the initial stage without frame thinning (full rate).

Next, after 1 hour has elapsed, the recording data stored at 30 fps is taken out, the taken-out recording data is converted to 15 fps, and the converted recording data is converted into the first recording data.
Stored on the hard disk 211 (at this time, the original 3
The recorded data of 0 fps will be erased. ).

Next, after the lapse of 12 hours, the recording data stored at 15 fps is taken out, the taken-out recording data is converted to 5 fps, and the converted recording data is converted into the first recording data.
Stored on the hard disk 211 (at this time, the original 1
The recorded data of 5 fps will be erased. ).

Further, after 24 hours, the recorded data stored at 5 fps is taken out, the taken-out recorded data is converted to 1 fps, and the converted recorded data is stored in the second hard disk 212 (at this time, The original recorded data of 5 fps will be erased.)

In accordance with the conversion timing data 30 indicating the processing contents, the frame rate conversion unit 31 stores the converted recording data in the first or second hard disk 211, 212 while repeating the data conversion.

Here, the method of performing the frame rate conversion processing on the recording data whose conversion timing has elapsed may be a method of sequentially processing the recording data whose conversion timing has elapsed, or a method of performing conversion processing of the conversion timing. The elapsed recording data may be accumulated in a predetermined frame and then batch processing may be performed. Alternatively, the conversion timing may be determined for each file including a plurality of frame images, and the frame rate conversion process may be performed for each file including a plurality of frame images.

As a method of judging the passage of time, for example, the recording time may be written in the header of each frame image and compared with the system timer, or it may consist of a plurality of frame images. The recording time may be managed for each file, and the recording time for each file may be compared with the system timer. Even when the compression rate or the resolution is changed as the conversion process, the recording time may be written in the header of each frame image, or the recording time may be managed for each file including a plurality of frame images. Good.

FIG. 4 is a diagram comparing the recording method of the present invention with the conventional recording method. Conventionally, from the viewpoint of saving the hard disk capacity, from the beginning of shooting, an image was recorded at 1 fps with a small data size. With this method, the data size is small from the initial state, so it is excellent in reducing the amount of recorded data, but since the frame rate of recorded data is low immediately after shooting, you can check the recorded video immediately after the problem occurs. However, there was a problem that he did not capture the decisive moment.

On the other hand, in the recording system of the present invention, while the reproducibility of the recorded image with high accuracy is ensured by the high frame rate immediately after the photographing, the recorded data of the past whose need is gradually diminished. By sequentially reducing the frame rate, the data capacity is reduced and the hard disk capacity is saved.

That is, in many cases, the work of replaying and confirming a suspicious person displayed in the video for a moment and the work of checking the situation when a problem actually occurs are performed immediately after recording. Therefore, in the initial stage, the image is recorded with high image quality without frame thinning.

On the other hand, since time has passed since the image was taken, the situation is often confirmed from uncertain information. In other words, the sighting information and the memory become rough information as time passes, so that wide shallow information is needed rather than a detailed situation. Therefore, even if the frames of the initially recorded video are thinned out according to the elapsed time, the purpose of the recorded video is achieved. And finally, it is stored at the frame rate conventionally used for long-time recording.

FIG. 5 shows the first hard disk 211, the second hard disk
6 is an image diagram showing a storage state of video recording data recorded on a hard disk 212. FIG. As described above, the frame rate of the recorded data stored in the first hard disk 211 gradually decreases with the passage of time, and finally the recorded data of 1 fps having the smallest frame rate is stored in the second hard disk for long-term storage. It is stored in 212. Further, it is possible to back up the recorded data of high frame rate as required.

The case where the frame rate changing process is performed has been described above as an example, but the same process is performed in another method, a compression rate converting method, and a resolution converting method.

An example of processing for converting the compression rate will be shown. Immediately after shooting, recorded data having a very small compression rate (or a compression rate of 0) is stored in the first hard disk 211. After 1 hour, the compression rate is increased (for example, the compression rate is 30%) to convert the recorded data, and the converted recorded data is stored in the first hard disk 21.
Store in 1. Further, after 12 hours, the compression rate is further increased (for example, the compression rate is 50%) and the converted recording data is stored in the first hard disk 211. Then, after the lapse of 24 hours, the recording data having a higher compression rate (for example, a compression rate of 70%) is stored in the second hard disk 212 for long-term storage. Such conversion processing is executed by the compression ratio conversion unit 32. However, the conversion timing and the compression rate can be freely set as appropriate.

Next, an example of processing for converting the resolution will be described. Immediately after shooting, recorded data having a very high resolution (for example, 720 × 480 pixels) is stored in the first hard disk 211. Then, after 1 hour has elapsed, the resolution is reduced (for example, the resolution is set to 320 × 240 pixels) to convert the recorded data, and the converted recorded data is stored in the first hard disk 211. After 12 hours, the resolution is further reduced (for example, the resolution is 160 × 120 pixels) and the converted recording data is stored in the first hard disk 211. Then, after the lapse of 24 hours, the recorded data with the resolution further reduced (for example, with a resolution of 120 × 96 pixels) is stored in the second hard disk 212 for long-term storage. Such conversion processing is executed by the resolution conversion unit 32. However, the conversion timing and resolution can be freely set as appropriate.

<3. Mark Function> As described above, the video recording device 20 according to the present embodiment performs a predetermined conversion process so that the data size of the recorded data becomes smaller with the passage of time.

However, it is preferable to store the recorded data of an important portion at a high frame rate or high image quality even if the recorded data has passed the time. The mark function is a function for storing recorded data at a high frame rate or high image quality regardless of the passage of time.

The monitor uses the monitor 22 to display a real-time image or the first hard disk 211, the second hard disk.
It is possible to refer to the recorded data stored in the hard disk 212. When the surveillance staff member finds a portion to be noted while referring to the recorded data, the operation unit 23 is used to input a mark addition instruction at that time. When the mark addition instruction is input, the mark addition unit 205, for the video input in real time, with respect to the high-quality recorded data stored in the first hard disk, or the first hard disk 21.
First, the designation information designating the time zone (video portion) in which the mark is instructed is added to the past recorded data stored in the second hard disk 212.

In this way, when the mark adding section 205 adds the designation information to the important portion of the recorded data,
The conversion storage unit 202 reduces the data size of the video portion designated by the designation information (A).
The high frame rate or high quality recorded data is maintained without performing the conversion process of (1) to (C).

By having such a function, the video recording apparatus 20 according to the present embodiment can store recorded data of high frame rate or high image quality retroactively. That is, when the recorded data is stored at a low frame rate or a low image quality immediately after shooting as in the conventional case, real-time monitoring is performed to store important parts at a high frame rate or high image quality. Marks must be added to important parts in the state. On the other hand, the video recording apparatus according to the present embodiment can store the recording data of high frame rate and the recording data of high image quality retroactively from the time when the problem occurs.

As described above, the video recording apparatus 20 according to the present embodiment records the recording data at a relatively high frame rate at the initial storage. Since this recorded data is stored for a certain period of time (1 hour of full-rate video in the example in Table 1), play it back during that time to check the status, back up if necessary, and mark it as an important video. You can take action to change the frame thinning rate.

The image recorded at the full rate is stored for a certain period of time, then read from the first hard disk 211, subjected to frame thinning processing at 15 fps, and again returned to the first recording.
It is written in the hard disk 211. Since this video is also stored for a certain period (12 hours in the example of Table 1), the quality of the video is slightly deteriorated, but it is suitable for the situation check and backup as in the first video.

The same processing is performed, and finally the video dropped to the frame rate for long-term storage (1 fps in the example of Table 1) is recorded on the second hard disk 212 for long-term storage. The second hard disk 212 has a replaceable structure, and when the data becomes full, the second hard disk 212 can be replaced sequentially to store the recorded data for a long time.

In the present embodiment, the second hard disk 21
Even if the second data is full, if the first hard disk 211 has enough space, the data can be temporarily stored, so that it is possible to prevent the loss of the image due to the replacement of the second hard disk 212.

In addition, there is a pre-record function as a mechanism for recording at full rate only before and after the sensor responds to record by thinning out frames, which requires a large capacity memory. The video recording device 20 does not need such a large-capacity memory in order to record the full-rate recording data once at the initial stage.

{Modification} In the above embodiment, the recorded data immediately after shooting is stored at a high frame rate or a high image quality, and the frame rate is lowered or the image quality is lowered over time. On the other hand, both high frame rate recording data and low frame rate recording data may be stored immediately after shooting, or both high image quality recording data and low image quality recording data may be stored. .

Then, the recorded data stored in the first hard disk 211 with a high frame rate or high image quality is deleted as time passes, and the recorded data stored with a low frame rate or low image quality is stored for a long time from the beginning. It may be stored in the second hard disk 212 for storage. By adopting such a method, the same effect as that of the above-described embodiment can be obtained.

Further, the recorded data may be stored at a plurality of types of frame rates immediately after shooting, or the recorded data may be stored at a plurality of types of image quality.

For example, immediately after shooting, 1 fps and 5 fp
Recording data of four types of frame rates of s, 15 fps, and 30 fps are stored in different hard disks. Of these, the recorded data of 1 fps is stored in the hard disk for long-term storage from the beginning. The recorded data of 30 fps is deleted after 1 hour, the recorded data of 15 fps is deleted after 12 hours, and the recorded data of 5 fps is 24.
It will be deleted after a while. In this way, since the recorded data of the lowest frame rate is stored in the hard disk for long-term storage, the capacity of the hard disk for long-term storage can be kept low. In the hard disk in which the recorded data with a relatively high frame rate is stored, the recorded data is deleted over time, so that the data capacity does not increase indefinitely.

Further, when a plurality of recorded data having different compression rates are stored, the compression rates are set to 0 immediately after shooting.
Recording data of%, 30%, 50%, 70% may be stored. At this time, the recorded data having a compression rate of 70% is stored in the hard disk for long-term storage from the beginning.
After 1 hour, the recording data with a compression rate of 0% is deleted, after 12 hours, the recording data with a compression rate of 30% is deleted, and after 24 hours, the recording data with a compression rate of 70% is deleted. do it. However, the time of conversion timing and the compression ratio of a plurality of recordings to be stored can be freely set according to the application.

Further, when a plurality of recorded data having different resolutions are stored, the resolutions of the recorded data are set to 72 immediately after shooting.
0x480 pixels, 320x240 pixels, 160x120
Recording data of 120 × 96 pixels may be stored. At this time, the recorded data having a resolution of 120 × 96 pixels is stored in the hard disk for long-term storage from the beginning. And after 1 hour, the resolution is 720 × 480.
Pixel recording data is deleted, and the resolution is 32 after 12 hours.
The recorded data of 0 × 240 pixels may be erased, and after 24 hours, the recorded data of resolution 160 × 120 pixels may be erased. However, the conversion timing time,
The resolution of a plurality of recordings to be stored can be freely set according to the purpose.

Thus, by recording a plurality of images of different frame rates, a plurality of images of different compression ratios, or a plurality of images of different resolutions immediately after shooting,
Similar to the above-described embodiment, it is possible to refer to a necessary video as time passes. In addition, it is possible to properly use a reference image from a plurality of images according to the purpose. Finally, since the recorded data that is stored for a long period has a small data size, it is possible to suppress the capacity of the storage device.

As described above, according to the embodiment of the present invention, as the method of changing the data size, three methods of operating the frame rate, the compression rate, and the resolution are mentioned. However, as the method of changing the data size, the data amount is changed. Other methods that can reduce may be used.

[0069]

As described above, according to the first or seventh aspect of the invention, after the recording data having a relatively large data size is stored, the data size is reduced after a lapse of a predetermined time and new recording is performed. Since it is stored as data, it is possible to refer to an image having excellent image quality after a predetermined time has elapsed after shooting, and it is possible to reduce the data size of the recorded video data for storage after the predetermined time has elapsed. .

In the invention according to claim 2 or claim 8,
After storing a video with a large data size, the data size is gradually reduced, so that while maintaining the required image quality over time, finally a video with a small data size suitable for storage To be converted.

According to the third aspect of the invention, since the recorded data is stored in the storage device for long-term storage after the conversion process is finally performed, the maintainability is excellent.

According to the fourth aspect of the invention, the information for designating a specific time zone portion in the recorded data is added, and
Since the conversion processing for reducing the data size is not performed in the time zone portion, high image quality can be maintained for the video of the important portion.

According to the invention of claim 5 or claim 9,
Since a plurality of videos with different frame rates are recorded, it is possible to refer to the video according to the application.

The invention according to claim 6 or 10 is
Immediately after the shooting time, it is possible to refer to an image having excellent image quality, and finally, only an image having a small data size suitable for long-term storage is left.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an entire monitoring system.

FIG. 2 is a functional block configuration diagram of a video recording device.

FIG. 3 is a functional block configuration diagram of a conversion storage unit.

FIG. 4 is a diagram comparing an example of a recording method of the present invention with a conventional recording method.

FIG. 5 is an image diagram showing a storage state in a hard disk.

[Explanation of symbols]

20 Video recorder 21 camera 22 monitors 23 Operation part 202 conversion storage unit 211 First hard disk 212 Second hard disk

Claims (10)

[Claims] 1. A device for recording a video image taken by a photographing device, wherein the data size can be changed by converting at least one of a frame rate, a compression ratio and a resolution of the recorded data, A video input unit for inputting a video image captured by the image capturing apparatus; a unit for storing the video image input by the video input unit in a storage device as recording data having a relatively large data size; For the recorded data over time, a conversion process is performed to reduce the data size of the recorded data, and the converted recorded data is replaced with new recorded data in the storage device instead of the original recorded data. And a means for storing the video recording apparatus. 2. A device for recording a video image taken by a photographing device, wherein the data size can be changed by converting at least one of a frame rate, a compression rate and a resolution of the recorded data, Image input means for inputting an image captured by the image capturing device; initial data storage means for storing the image input by the image input means in a storage device as recorded data having a relatively large data size; and the initial data storage means A plurality of conversion timings with different elapsed times from the time when the recorded data is stored are specified, and the recorded data whose conversion timing has passed is subjected to conversion processing to reduce the data size of the recorded data. , The converted recording data is stored in the storage device as new recording data in place of the original recording data. A video recording device comprising: a conversion storage means. 3. The video recording apparatus according to claim 2, wherein the conversion storage unit stores the recording data after conversion by the conversion storage unit at a final conversion timing having the longest elapsed time among the conversion timings. A video recording device, comprising means for storing in a storage device for long-term storage. 4. The video recording apparatus according to claim 2 or 3, further comprising designation information for designating a specific time zone in the recorded data, with respect to the recorded data stored in the storage device. The conversion storage means further includes, for the time zone designated by the designation information in the recorded data, the designation information without lowering the frame rate even after the conversion timing has elapsed. A video recording apparatus comprising: a unit that maintains a frame rate when the frame is added. 5. A device for recording a video image taken by a photographing device, wherein the data size can be changed by converting at least one of a frame rate, a compression rate and a resolution of the recorded data, A video input means for inputting a video taken by the shooting device; a means for storing the video input by the video input means in a storage device as a plurality of recorded data having different data sizes,
A video recording device comprising: 6. The video recording apparatus according to claim 5, wherein a deletion time from the time of being stored in the storage device is defined for each of the plurality of recorded data having different data sizes. The deletion time is defined to be shorter for recorded data with a larger data size, and the recorded data with the smallest data size is stored for a long time without being deleted. 7. A method applied to a video recording device for recording a video image captured by a video recording device, wherein the video recording device converts at least one of a frame rate, a compression rate and a resolution of recorded data. It is possible to change the data size by the video input step of inputting the video image captured by the image capturing device, and storing the video image input in the video input step in the storage device as recording data having a relatively large data size. The process and the recording data which has been stored in the storage device for a predetermined time have been subjected to conversion processing to reduce the data size of the recording data, and instead of the original recording data, the converted data Storing the recorded data as new recorded data in the storage device. 8. A method applied to a video recording apparatus for recording video taken by a video recording apparatus, wherein the video recording apparatus converts at least one of a frame rate, a compression rate and a resolution of recorded data. It is possible to change the data size by the video input step of inputting the video image captured by the image capturing device, and storing the video image input in the video input step in the storage device as recording data having a relatively large data size. An initial data storage step and a plurality of conversion timings with different elapsed times from the time when the recording data is stored in the initial data storage step are defined, and the recording data for which the respective conversion timings have elapsed is recorded. The conversion processing is performed to reduce the data size of the data, and the recorded data after conversion is used instead of the original recorded data. And a conversion storing step of storing the image data as new recording data in the storage device. 9. A method for applying to a video recording device for recording a video image taken by a shooting device, wherein the video recording device converts at least one of a frame rate, a compression rate and a resolution of recorded data. It is possible to change the data size by the video input step of inputting the video image captured by the image capturing device, and storing the video image input in the video input step in the storage device as a plurality of recording data having different data sizes. A video recording method comprising the steps of: 10. The video recording method according to claim 9, wherein a deletion time from a point of time when the video data is stored in the storage device is defined for each of the plurality of video data having different data sizes. The deletion time is specified to be shorter for recorded data with a larger data size, and the recorded data with the smallest data size is stored for a long time without being deleted.