JPH1169296A - Image/voice recording and reproducing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To record a decisive moment and abnormal situation by monitoring whether a button has been depressed or not and executing kick-back processing which record-processing video and voice before the pressing time point and multiplexing of compressed video signal, so as to generate a system stream used for a monitoring camera. SOLUTION: Signals collected by a lens 101 are combined on an image-pickup device 102 and converted into electrical signals, which are compressed by a video processing part 106 through a camera processing part 103 such as white balance to generate a video stream. Meanwhile for voice, signals collected by a microphone 104 are converted into digital signals by an A/D converter 105, stored in an audio buffer 107, and compressed by an AUDIO part 110 to generate an audio stream. Video and audio streams have a system stream generated by a multiplexing part 113 and when a kick back recording button 109 is depressed, are recorded in a record medium as a system stream.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video / audio recording / reproducing apparatus such as a video camera, a surveillance camera, an electronic still camera, and a telephone.

[0002]

2. Description of the Related Art A video camera is currently realized as a camera for recording moving images. In this type of camera, when a recording button is pressed, signals collected by a lens are combined on an image sensor, converted into an electric signal, further converted into a video signal, and recorded on a recording medium.

In a video camera, recording is started from the moment when the photographer presses the record button. If the timing of pressing the record button is delayed due to the photographer forgetting to press the button, the decisive moment is missed. Become.

A surveillance camera is also known as a camera capable of recording for a long time. When the recording button is pressed in the surveillance camera, an enormous recording medium is required to continue recording for a long time.

[0005]

SUMMARY OF THE INVENTION Therefore, in the present invention, an image / audio recording / reproducing apparatus capable of recording / reproducing a video / audio before the moment when a button is pressed is used as a video camera. In the case, do not miss a decisive moment, and when used as a surveillance camera, if the abnormal situation occurs even if you do not keep recording for a long time, press the kickback recording button to record the movie before it is pressed So you can record the moment when an abnormality occurs.

[0006]

A lens, an image sensor, a camera signal processor for converting an electric signal into a video signal, a microphone,
An M / A converter that converts an input audio signal into a digital signal, a video processing unit, an audio buffer, and the like.
PEG CODEC part, kickback recording button, MP
It comprises a microcomputer for processing the EG AUDIO section and the kickback processing section, a multiplexing section for multiplexing a video stream and an audio stream to generate a system stream, and a recording medium for recording the system stream.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. First, the operation of the embodiment of the present invention will be described.

FIG. 1 is a block diagram of one embodiment of the present invention. In the figure, 101 is a lens, 102 is an image sensor, 103 is a camera signal processing unit that converts an electric signal into a video signal, 104 is a microphone, and 105 is an A / D that converts audio input from the microphone 105 into digital. Converter,
Reference numeral 106 denotes a video processing unit for compressing the video signal of the camera signal processing unit 103 to generate a video stream; 107, an audio buffer for temporarily storing the digital audio signal output from the A / D conversion unit 105; An MPEGCODEC unit including a processing unit 106 and an audio buffer 107, a skipback recording button 109, an MPEG AUDIO unit 110 for compressing a digital signal output from the A / D conversion unit 105 to generate an audio stream, and 111 for an audio stream A kickback processing unit that monitors whether the kickback recording button 109 has been pressed and performs kickback recording processing when pressed.
A microcomputer for processing the PEG AUDIO unit 110, the kickback recording unit, and the like.
Video stream compressed with MPEGAUDI
A multiplexing unit for synchronizing and multiplexing the audio stream compressed by the O unit 110 to generate a system stream; 114, an MPEG camera using the present invention;
Is a recording medium for recording a system stream.

Hereinafter, this embodiment will be described. The signals collected by the lens 101 are combined on the image sensor 102 and converted into electric signals. Video processing unit 1 via well-known camera signal processing unit 103 such as white balance
At 06, a video stream is generated. On the other hand, the audio signal collected by the microphone 104 is converted into a digital signal by the A / D converter 105 and is converted into a digital signal by the audio buffer 1.
07, and the MPEG AUDIO unit 110 compresses the audio data to generate an audio stream. The multiplexing unit 113 generates a system stream for the video stream and the audio stream. Multiplexer 113 until kickback recording button 109 is pressed
The system stream generated by the recording medium 11
When the writing is continued in the ring-shaped file on 5 and the button is pressed, it is recorded on the recording medium 115 as a system stream.

The system stream generated by the multiplexing unit 108 is shown in FIGS. 1, 2, 3, 4, 5, and 6.
This will be described with reference to FIG.

FIG. 2 shows a system stream generated by the multiplexing unit 113. As one specific example, a system stream of one pack and one packet is shown. 201 is a pack header, 202 is a system header attached only to the head of the system stream, 203 is a packet, 204 is a pack header, 205 is a packet, and 206 is an end code indicating the end of the system stream. Thus, the system stream is a collection of several packs, and a packet exists in a pack.

Next, the packet will be described with reference to FIGS. 3, 4, 5 and 6. FIG. There are three types of packets: video packets, audio packets, and padding packets.

FIG. 3 shows the structure of a video packet. 30
1 is a packet header and 302 is a video stream. The video stream is shown in FIG. 401 is a sequence header, 402 is a GOP (Group Of Pictures), 4
03 is an end code of the sequence. In one GOP,
Normally, 15 screens are grouped, and at least one of these screens includes screen data closed only by one without using information of the previous and next screens. This GOP is also used for random access and the like.

FIG. 5 shows the structure of an audio packet.
Reference numeral 501 denotes a packet header, 502 denotes an audio stream, and 503 denotes a minimum unit (frame) that can be decoded into an audio signal called an AAU (Audio Access Unit). Reference numeral 504 denotes a header including audio reproduction information, and reference numeral 505 denotes compressed audio data.

FIG. 6 shows the structure of a padding packet.
601 is a packet header, 602 is a padding stream, and 603 is all 1 padding data. This padding packet is used as a dummy packet, and this data is ignored during playback.

Next, skip back recording will be described with reference to FIG.
This will be described with reference to FIGS. 7, 8, 9, and 10. As a specific example, 5 points from the time when the skip back recording button is pressed
A case in which recording is performed as far back as minutes will be described.

First, when the skip back recording mode is set, two files, file A and file B, are opened in the recording medium 115 in FIG. The timer 702 switches the file to which the system stream is written to the file A 703 and the file B 704 every 5 minutes. At 705, it is always checked whether the skip-back recording button has been pressed, and the routine returns to 702 until the skip-back recording button is pressed, and repeats 703 for writing to file A and 704 for writing to file B every 5 minutes.
When the kickback recording button is pressed, the file division / combination processing of 706 is performed. A specific example of the file division and coupling process will be described with reference to FIGS. 2, 4, 7, 8, and 9. FIG.

FIG. 8 shows the files A and B opened in 701 of FIG. It is assumed that the kickback recording button is pressed at 801 of file A. 90 in FIG.
At 1, the end processing of the file is performed at 801 of the file A in FIG. This is obtained by adding the sequence end code 403 in FIG. 4 and the end code 206 in FIG.
At 902, it is checked how much the system stream has been written to the file A. That is, 80 in FIG.
Check the number of GOPs in the system stream from 2 to 801. At 903, the file A is closed at 801 in FIG. In step 904, the file B and the file A are divided and combined when the total of the files becomes 5 minutes. A specific example of this division coupling process will be described with reference to FIGS. 2, 3, 4, 8, and 10. FIG.

First, at 1001 in FIG. 10, a GOP break of the file B is searched so that the total of the system streams of the file A and the file B becomes 5 minutes. That is, 802 to 801 of file A and 80 of file B in FIG.
A search is made for a file B 803 such that the total of GOPs 3 to 804 is 5 minutes of data. 803 for 1002
Split the extra system stream. Since the division of the file is performed in GOP units of the video stream, the GOP is divided at a portion where the beginning of the GOP is 803. 1
In 003, the sequence header 40 of FIG.
1. A packet header 301 shown in FIG. 3, a pack header 210 shown in FIG. 2, and a system header 202 are added. At 1004, file B is combined before file A. In step 1005, a time stamp used for synchronously reproducing video and audio is changed. Next, the time stamp will be described.

The time stamp includes a PTS (Presentation)
Time Stamp, playback management time management information), DTS (Dec
oding Time Stamp, decryption time management information), SCR (Sy
stem clock reference, system time reference value)
There is a relative time.

The PTS and DTS are information included in the video packet header, and the PT after the file B is divided.
For S and DTS, the PTS and DTS of the video packet header at the divided point are copied and used as they are.

The SCR is information included in the pack header, and the head pack header is calculated by the following equation. SCR of the second pack from the beginning is SCR2
Then, the SCR to be obtained can be calculated from SCR = SCR2-((bit number of pack × 90000) / (bit rate × 400)).

Furthermore, TC (Time) in the video stream
Code). This indicates the time from the beginning of the sequence and is attached to each GOP. Therefore, the TCs of all GOPs are changed. In this way, a system stream 5 minutes before the button is pressed is completed.

Next, as a second embodiment, kickback recording of only audio will be described with reference to FIGS. 5, 7, and 11. FIG.

In MPEG AUDIO, the AAU shown in FIG.
Only 503 can be reproduced. Therefore, the split join is A
Execute based on AU. First, when the audio skip back recording mode is set, the recording medium 115 in FIG.
The file A and the file B are opened. This is shown in FIG. In the timer of 702,
The file in which the system stream is written is switched between file A 703 and file B 704 every 5 minutes. 705
Then, it is always checked whether the audio skip-back recording button is pressed, and the process returns to the above-mentioned step 702 until the audio skip-back recording button is pressed. When the kickback recording button is pressed, a file combining process of 706 is performed. A specific example of the file division coupling process will be described with reference to FIGS. 5, 8, and 11. FIG. It is assumed that the audio skip back recording button is pressed at 801 of file A in FIG.

First, at step 1101 in FIG. 11, a break in the AAU of the file B is searched so that the sum of the AAUs of the file A and the file B becomes 5 minutes of audio data. That is, file A 802 to 801 and file B in FIG.
The file B 803 is searched such that the sum of the AAUs 803 to 804 becomes 5 minutes of data. At 1102, an extra audio stream is divided at the 803 portion.
Since the file is divided in units of AAU of the audio stream, the file is divided at a portion where the head of the corresponding AAU is 803. At 1103, the file B divided before the file A is combined to complete the audio stream.

[0027]

According to the present invention, the moving image or the sound before the moment when the button is pressed is recorded, so that the decisive moment of photographing is not missed. Further, when used as a surveillance camera, an enormous recording medium is not required.

[Brief description of the drawings]

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

FIG. 2 is a diagram illustrating a system stream generated by a multiplexing unit 113 in FIG.

FIG. 3 is a diagram illustrating a video packet.

FIG. 4 is a diagram illustrating a video stream.

FIG. 5 is a diagram illustrating an audio packet.

FIG. 6 is a diagram illustrating a padding packet.

FIG. 7 is a flowchart illustrating a process of a kickback recording unit in FIG. 1;

FIG. 8 is a diagram illustrating a state of a file on a recording medium in a kickback recording mode in FIG. 1;

FIG. 9 is a flowchart illustrating processing of a kickback recording unit in FIG. 1;

FIG. 10 is a flowchart illustrating processing of a kickback recording unit in FIG. 1;

FIG. 11 is a flowchart illustrating processing of a kickback recording unit in FIG. 1;

[Explanation of symbols]

101: lens, 102: imaging device, 103: camera signal processing unit, 104: microphone, 105: A / D conversion unit, 1
06: Video processing unit, 107: Audio buffer, 1
08 ... MPEG CODEC part, 109 ... button, 11
0: MPEG AUDIO unit, 111: kickback recording unit, 112: microcomputer, 113: multiplexing unit, 114:
MPEG camera, 115 ... recording medium.

Claims (6)

[Claims] A lens, an image pickup device for combining the collected signals into an electric signal, a camera signal processing unit for converting the electric signal into a video signal, a microphone, a button, and an MPEG C for compressing and expanding the video signal.
An ODEC section, an MPEG AUDIO section that compresses and expands audio signals, a kickback processing section that monitors whether a button has been pressed and records video or audio prior to the present time when pressed, a compressed video signal and audio signal An image / audio recording / reproducing apparatus, comprising: a multiplexing unit that multiplexes a stream to generate a system stream; and a recording medium that records the system stream. 2. The video / audio recording / reproducing apparatus according to claim 1, wherein said video / audio recording / reproducing apparatus records a moving image before a moment when a button is pressed. 3. The video / audio recording / reproducing apparatus according to claim 1, wherein said video / audio recording / reproducing apparatus records a voice before a moment when a button is pressed. 4. The video / audio recording / reproducing apparatus according to claim 1, wherein at least one file is formed in a ring shape on said recording medium, and data is continuously written until a button is pressed. 5. The video / audio recording / reproducing apparatus according to claim 1, wherein the kickback recording section divides and combines the MPEG system stream in GOP units. 6. The kickback recording unit according to claim 1, wherein
2. The video / audio recording / reproducing apparatus according to claim 1, wherein the audio stream in the UDIO format is divided and combined in AAU units.