JPH09214926A - Information recording / reproducing device - Google Patents

Abstract

(57) [Abstract] [Problem] Information such as images and sounds to be recorded can be recorded without missing a moment. Encoded data access control means 50
Encoded data memory unit 51 composed of a buffer memory for storing encoded data of image / audio from the partner terminal
And the encoded data in real time in the memory unit 5
1 and a memory control unit 56 for reading from the memory unit 51. The memory unit 51 has a data area for storing a predetermined amount of data as a part thereof, and the memory control unit 52 always records the latest data repeatedly until a predetermined operation is executed in the data area. Control.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording / reproducing apparatus, and more particularly, to recording / reproducing and communication of images and sounds of surveillance cameras and video conference systems.

[0002]

2. Description of the Related Art In recent years, video conferencing systems have exchanged visual information such as characters and figures in real time with the other party by using a display device or the like in addition to voice communication means used in conventional telephones. It has been developed as a possible means, CCITT has made a formal recommendation of a video encoding method and a multiplexing method for audiovisual services, and a communication procedure, and with the widening of corporate activities and the spread of digital communication networks, Video conferencing systems and video TVs that comply with CCITT recommendations from companies
Phones, etc. are being developed.

Japanese Laid-Open Patent Publication No. 6-269005 discloses that image or audio coded data at the time of communication is stored and updated in a buffer memory of a coded data storage unit in real time from an arbitrary time point according to a user's request. A video conference system has been proposed in which data can be decrypted to instantly reproduce the data without using a recording medium such as a VTR.

[0004]

However, according to the method for executing the quick recording and reproducing described in the above publication,
If there is information to be recorded and this information is instantaneous information, that information cannot be recorded. In addition, it often happens that the information to be recorded should be recorded for a while after the appearance of the information to be recorded, and even in this case, there is a problem that a part of the image to be recorded cannot be recorded.

The present invention has been made in view of the above-mentioned circumstances, and provides a means for recording information such as an image and a sound to be recorded without missing a moment, and among the information recorded by the means. Providing a means for quickly reproducing (or displaying) desired information, and further, when the image information to be recorded does not change (or is considered to be small), the memory is effectively used to record the recorded information. At the level of confirmation, the purpose is to provide an inexpensive image recording / reproducing means that is sufficiently practical.

[0006]

According to a first aspect of the present invention, an encoded data memory unit composed of a buffer memory for storing encoded data of image / voice from a partner terminal and the encoded data in real time are provided. Write to the memory section,
And a memory control unit for reading from the memory unit, the memory unit having a data area for storing a predetermined amount of data as a part thereof, and the memory control unit for performing a predetermined operation in the data area. Characterized by having coded data access means for controlling to record the latest data repeatedly until it is executed, so that information such as images and sounds to be recorded can be recorded without missing a moment. Is.

According to a second aspect of the present invention, in the first aspect of the invention, the coded data access control means reads out only the beginning portion of the recorded data, thereby enabling a search reading section. The search reading section has a function of storing the recording start address of each recorded data block at the time of recording data, and starts reading from the recording start address at the time of reading data. At this time, if there is a search command, the access to the memory is controlled so as to start reading data from a specified address among the recorded addresses after reading for a predetermined time, Therefore, of the recorded information, desired information is quickly reproduced (or displayed).

According to a third aspect of the present invention, in the first or second aspect of the present invention, there is an encoded data change detection means, and the encoded data change detection means detects a change between screens of image information during data recording. For a screen determined to have little change, the screen is regarded as a motionless image, the coding information of only one screen, its address information, and the time information of the screen are recorded, and at the time of reading, When reading the data of the above address, it is characterized by repeatedly reading the data of the data block having that address as the start address for the continuous time according to the recorded time information. Inexpensive images that are practical enough at the level of checking the recorded information by effectively utilizing the memory when there is no change (or when it is considered to be small) It is obtained so as to provide a recording and reproducing means.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing an example in which the data access control means 50 according to the present invention is applied to a video conference system, but the present invention will be apparent from the following description. It will be easily understood that the present invention is not limited to the illustrated embodiment, but can be applied to all information (mainly image information) recording / reproducing devices. In FIG. 1, 1 is a camera, 2 is a document camera, 3 is a monitor, and 4 is a monitor.
Is a video I / F unit, 5 is a video codec unit, 6 is a demultiplexing unit, and 7 is a line I / F unit. As is well known, these are used to communicate image information with the other party. Also,
Reference numeral 11 is a data terminal, and 12 is a data I / F unit, which transmits and receives data. Similarly, 21 is a handset, 22 is a voice I / F unit, 23 is a voice codec unit, 31 is a touch panel, 32 is a drawing I / F unit, 33
Is a drawing data codec section which transmits and receives voice and drawing. In addition, 40 is a system control unit, 41 is an operation unit for operating the system control unit 40,
The operation unit 41 controls the system control unit 40, thereby controlling each block and setting the communication with the partner terminal.

[Invention of Claim 1] In FIG. 1, reference numeral 50 is an encoded data access control means according to the present invention. The encoded data access control means 50 comprises an encoded data memory section 51 and a memory control section 52. It consists of
The recording area of the encoded data on the memory is shown. Here, when the user wants to record the received information, the following operation is performed by performing an appropriate operation. The latest data is repeatedly recorded in the memory area I (when it is full, the recording data returns to the first recording start address and is recorded from there). That is, if the address a1 (hereinafter, refer to FIG. 2) is the recording start address of the data area of the memory section and the end address of the data area is b1, when recording is performed up to the address b1, it returns to a1 again and starts recording. Then, this is repeated (the already recorded data is changed to new data by overwriting).

Now, when a recording command is issued while writing data to the address c1, the operation is as follows.
After the writing to the address of c1 is completed, recording is continued with the next write address as the start address d1 of the data area II (this address may be the address next to b1).
When the recording stop operation is executed, the recording operation ends (the end address at this time is set to e1). Then, the reproduction start address is held as an address c1 'next to c1 (this function may be performed by the system controller). The address order (sequence) of reproduction is held as follows. After reading the data from c1 'to b1, the data from a1 to c1 is read next. Next, the data from the head address d1 of the second data area II to the recording end address e1 is read. When the above series of recording operations is completed, from the address f1 next to e1,
The pre-recording operation is started, and the pre-recording operation is continued until the pre-recording start operation is performed again.

Again, when the recording start operation is performed, the correspondence of the addresses in the explanation of the operation is f1⇔a1 and g1⇔b
1, h1 ⇔ c1, h1 '⇔ c1', i1 ⇔ d1, j1 ⇔
Since there is a relationship of e1, the repetitive description will be omitted. Less than,
The same operation as above is repeated (pre-recording start, end,
This recording starts, ends, holds the playback sequence for playback, etc.). As described above, after the user issues an instruction to start recording by key operation, etc., recording can be performed from the information received before that time, and the content can be instantly reproduced and confirmed. You can It is obvious that the transmission information can be recorded in the same manner.

[Invention of Claim 2] According to the invention of Claim 2, it is possible to read only the starting portion of the recorded data and means for storing the start address of the information recorded by the operation of Claim 1. An example of the operation of the search reading means having the search reading control means is as follows. At the time of data recording, the recording start address of each information is recorded from the recorded address information, but the storage location may be the memory in the system control unit,
The header information can be stored in an address other than the data area of the memory (FIG. 2) described in claim 1. Next, at the time of reading data, reading of data is started from the first recording start address. At this time, if there is a search command, the start address information is accessed to read the next recorded data. Start reading data from the start address. If there is no search stop command, the data block is read up to the final address of the data block being read. In the same manner, the reading control is executed in accordance with the presence / absence of the search command (here, the data block means that data is recorded until recording is started and recording is once stopped). Area in memory).

[Invention of Claim 3] FIG. 3 is a block diagram for explaining an embodiment of the invention of Claim 3, in which FIG.
Reference numeral 0 is a coded data change detecting means, and other parts are exactly the same as those in the embodiment shown in FIG. The operation of the encoded data change detecting means 60 is as follows. The total sum of absolute values of motion vectors between frames is calculated, and if the value is a predetermined value or more, it is determined that there is motion between frames, and if it is less than that, it is determined that there is no change. Recording of coded data is executed by the method described in claim 1, but at the same time, the motion vector of this coded data is also input to the coded data change detection means,
As described above, it is determined whether or not a change in the encoded data is detected for each frame. The operation of the encoded data access control means 50 for controlling the recording operation according to the result of the determination as to whether or not the change has been detected is as follows. When it is judged that the encoded data of the image received (or transmitted) does not change, until the judgment that there is a change, the first of the unchanged data is received (or transmitted). Was done 1
Encoded data of an image of only a frame and recording start address information of this data are recorded. In addition, time information (for example, the number of frames) when no change is detected is recorded.

Next, a series of operations will be specifically described. Now, it is assumed that a certain frame is k frame and the following frame is k + 1 frame. k frames and k + 1
When it is determined by the encoded data change detection unit that the encoded data of the frame does not change up to k + N, the recording of the image data of the new frame including the k + 1 frame is stopped until it is determined that there is a change. (K + N + 1
If a change from the k + N frame is detected in the frame, recording of frames up to k + N is stopped). At this time, only k frame data is recorded as the encoded data. Also, the start address where the k-frame data is recorded and the time information (the number of frames) when no change is detected
Are stored in predetermined memory areas. Similarly, next, it is assumed that no change is continuously detected in the data from the k + M to the k + M + L frames (the coded data from the k + N + 1 frame to the k + N + M-1 frame are all recorded). The encoded data to be recorded in this case is (k + M) frame data, the recording start address is the start address of the area in which the (k + M) frame encoded data is stored, and the time information is L + 1. .

Next, a description will be given of the operation at the time of reading these recording start addresses as m1 and m2, and the number of frames in the period judged to have no change as n1 and n2, respectively. First, m1, m2 and n1, n2 stored in the memory of the image data change detecting means are read out. When reading is started and the address of the read data matches any of them (assuming that it matches m1), after reading one frame of data stored in the area having that address as the start address, Returning to m1 again, the reproducing operation is executed. This operation is repeated n1 times,
After that, the frame data stored next is read out. The same applies to m2 and the like.

[0017]

According to the invention of claim 1, an encoded data memory unit composed of a buffer memory for storing image / voice encoded data from a partner terminal, and the encoded data in the memory unit in real time. A memory control unit for writing and reading from the memory unit, the memory unit has a data area for storing a predetermined amount of data as a part thereof, and the memory control unit has a predetermined area in the data area. Since it has a coded data access means that controls to record the latest data repeatedly until the operation is executed,
Information such as images and sounds that you want to record can be recorded without missing a moment, and can be quickly reproduced.

According to a second aspect of the present invention, in the first aspect of the invention, the coded data access control means reads out only the beginning portion of the recorded data to enable the search reading section. The search reading unit has a function of storing the recording start address of each recorded data block when recording data, and starts reading from the recording start address when reading data. At this time, if there is a search command, the memory access is controlled so as to start reading data from a specified address among the recorded addresses after reading for a predetermined time. It is possible to quickly reproduce (or display) desired information from among several kinds of recorded data.

According to a third aspect of the present invention, in the first or second aspect of the present invention, there is an encoded data change detection means, and the encoded data change detection means detects a change between screens of image information during data recording. However, for a screen determined to have little change, the screen is regarded as a motionless image, and the coding information of only one screen, its address information, and the time information of the screen are recorded and read out. , When reading the data of the above address, the data of the data block with that address as the start address is repeatedly read for the continuous time according to the recorded time information, so it changes to the image information you want to record. No (or
If it is considered to be small), the memory can be effectively used, and at the level of checking the recorded image information, the memory can be effectively used without impairing the practicality.

[Brief description of drawings]

FIG. 1 is a block diagram for explaining an embodiment of an image recording / reproducing apparatus according to the present invention.

FIG. 2 is a diagram showing a recording area of encoded data on a memory.

FIG. 3 is a block diagram for explaining another embodiment of the image recording / reproducing apparatus according to the present invention.

[Explanation of symbols]

1 ... Camera, 2 ... Document camera, 3 ... Monitor, 4 ... Video I / F section, 5 ... Video codec section, 6 ... Demultiplexing section,
7 ... Line I / F section, 11 ... Data terminal, 12 ... Data I
/ F section, 21 ... Handset, 22 ... Voice I / F section, 2
3 ... Voice codec section, 31 ... Touch panel, 32 ... Drawing I / F section, 33 ... Drawing data codec section, 40 ... System control section, 41 ... Operation section, 50 ... Encoded data access control means, 51 ... Encoded data Memory unit, 52 ... Memory control unit, 60 ... Encoded data change detecting means.

Claims (3)

[Claims] 1. A coded data memory unit composed of a buffer memory for storing coded data of image / voice from a partner terminal, and the coded data is written in the memory unit in real time and read from the memory unit. The memory unit has a data area for storing a predetermined amount of data as a part of the memory controller, and the memory control unit always operates until a predetermined operation is performed on the data area. An information recording / reproducing apparatus having an encoded data access means for controlling so as to repeatedly record the latest data. 2. The encoded data access control means,
The recording / reading section has a search / readout section that enables search / readout by reading out only the beginning portion of the recorded data. The search / readout section, at the time of data recording, has a recording start address of each recorded data block. And has the function of storing, and starts reading from the recording start address when reading data.
If there is a search command, the access to the memory is controlled so as to start reading data from a specified address among the recorded addresses after reading for a predetermined time. Information recording / reproducing apparatus described. 3. A screen having coded data change detection means, wherein the coded data change detection means detects a change between screens of image information at the time of data recording, and a screen judged to have little change is said screen. Is regarded as a motionless image, the coded information of only one screen, its address information and time information of the screen are recorded, and when the data of the above address is read at the time of reading, it is recorded. 3. The information recording / reproducing apparatus according to claim 1, wherein the data of the data block having the address as the start address is repeatedly read for the continuous time according to the time information.