JPH0227577A - Optical disk processor - Google Patents

Abstract

PURPOSE:To simplify a device by recording a moving picture and a still picture as video information and a voice signal attended with them on one and the same optical disk by adding respective frequency characteristic and reproducing them while repeating a high speed access with one unit of an optical head. CONSTITUTION:Video information A capable of recording and reproducing under an analog recording system is recorded in the outer peripheral part outside the approximate center of a disk and the video information B of a digital- encoded still picture from which a high S/N image is obtainable and a digital encoded voice information C attended with the still picture are recorded at a separate are in an inner peripheral part. Each of the reproduction of the information is executed by one unit of the optical head, the information preceding to an access is accumulated in a frame memory to cope with in order to smoothly switch the information under access and the average access time of the optical head is fixed at 60ms or below which is equivalent to the answering time of human eyes. Thus, the editting of the video information can be realized with a simple device constitution and the simplification of the device and easiness of an operation are attained.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an optical disc processing device using an optical disc in which an analog signal recording area and a digital signal recording area are provided in the same disc, and particularly relates to an optical disc processing device that uses an optical disc in which an analog signal recording area and a digital signal recording area are provided in the same disc. The present invention relates to an optical disc processing device suitable for editing information.

[Conventional technology]

2. Description of the Related Art Conventionally, there is an optical disc called a CD-V, which is used exclusively for playback and has analog video information recorded on the outside of the optical disc and digital audio information recorded on the inside. This requires the disc to be played at 180 rpm to play the outer video information.
5 minutes of playback is possible by rotating at high speed.
Also, the audio information inside can be played back from a compact disc (CD).
), it is possible to play for 20 minutes by rotating at the same constant linear velocity (CLV). but.

This type of disk device is used only for reproduction, and it is necessary to vary the number of revolutions between the inner and outer circumferences.

[Problem a that the invention seeks to solve]

There are video program production machines that edit video programs using video information, audio information, etc. for the purpose of education and advertising.

These video information are read out as signals from optical video discs and video tape recorders, and audio information is read out as signals from CDs and digital audio chips (DA'I'), and each signal is read out from a videotape recorder. The method is to create a video program by processing it using a video editing machine. However, this method has the problem that editing operations become complicated.

An object of the present invention is to record and reproduce video information and audio information on the same optical disk using one optical head, thereby simplifying the system implementation and operation.

[Means to solve the problem]

The above purpose is to record the video information of moving images on the outer circumference of one disc using an analog signal recording method, and record the video information and audio information of still images on the inner circumference using a digital signal recording method. By accessing each area at high speed using the optical head of the stand and reproducing the information, the information before the start of access is stored in the frame memory at the time of access.

Article G1 for video programs will become possible.

[Effect]

To ensure a high S/N ratio for video information, moving images are recorded in analog on the outer circumference of the disk, and still images are digitally encoded, compressed, and digitally recorded on the inner circumference of the disk. Digital recording of moving images has a data transfer rate of 100 MHz/s or more, and analog recording is used because it is difficult to use an optical head in the 1990s. Also,
After the audio information is digitally encoded, it is digitally recorded on the inner periphery of the digital data in the same way as still images of video information.

Each piece of information is reproduced using a single optical head, but in order to smoothly switch the information being accessed, the information immediately before the access is stored in the frame memory. It is desirable that the response time of the eye is 60 m s or less. By doing this,
Editing of video information can be realized with a simple device configuration.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. 1st
The figure shows an example of a disk. Video information A, which can be recorded and reproduced using an analog recording method, is recorded on the outer periphery of the disk from approximately the center to the outside. As an analog recording method, there is a frequency variable M (FM) modulation method which is currently used in commercially available optical video discs. Second
Figure 3 shows a block diagram of the FM modulation recording signal system, and Figure 3 shows the relationship between the waveforms of each part and the recorded bits.
MHz) and an audio carrier wave (b) (0, 1 to I MHz) FM-modulated with an audio signal at a certain amplitude ratio to obtain a composite wave (Q).

After that, the 5 combined waves become a square wave (d) by a limiter,
Bits (θ) are formed on the optical disk by driving the semiconductor laser with this square wave.

To reproduce the signal, read bit (e) with an optical head to obtain a square wave (d), separate the audio carrier wave and video carrier wave with a filter, and then perform FM demodulation to obtain the video signal and audio signal. .

Video information B of a digitally encoded still image from which a high S/N image can be obtained and audio information C accompanying this still image are digitally encoded in the inner circumference inside from the moving image recording area in the approximate center of the optical disc. and recorded in separate areas. Various methods have been studied for highly efficient encoding of still image data of NTSG signals. For example, there is a method that combines interfield interpolation 2fsc sub-Nyquist sampling and variable length encoding of DPCM code. This method is described in the document ``Yokoi et al. Study of still image files used in image response systems: Institute of Electronics, Information and Communication Engineers.

This is described in detail in IE87-55J, but since it is different from the gist of the present invention, the explanation will be omitted. According to this, it is possible to compress the image data amount of one screen (approximately 756 bytes) to 80 bytes on average, and at most 118 bytes or less.

As a method for digitally encoding audio information.

Compact disks (CDs) currently available on the market can be used. Figure 4 (a) and Cb') show the recording signal processing and playback signal processing sequences in the case of a CD. During recording, the audio signal is re-digitized by A/D conversion, and then an error correction code (FLCC) is added. , is encoded by an encoder that includes interleaving as a countermeasure against burst defects, and is further encoded by a modulation path along with control signals and synchronization signals.
uration) is modulated. The bit frequency of this EFM modulated signal is normally 2.03 Mbit/s, but in consideration of the rotation speed and bit length, the bit frequency is increased four times to 8.12 Mbit/s by a clock converter, and the address After adding the signal, bits are formed on the disk by modulating the semiconductor laser of the light source with this signal. To reproduce the audio signal, the reproduced signal reproduced from the bits by the optical head is passed through the clock converter again, then inputted to the EFMtu adjustment circuit, decoded by the decoder and deinterleave, and then processed by the D/Δ converter. This is done by converting it into an analog signal.

An optical disk processing apparatus for recording and reproducing the optical disk shown in FIG. 1 will be explained using FIG. 5. An optical disk processing device can be broadly divided into (1) an optical head, (2) an access circuit for high-speed access to the optical head, and (3) FM.
Modulation/demodulation circuit (4) Digital modulation/demodulation circuit for still images,
(5) Audio signal modulation/demodulation circuit, (6) Image processing circuit, (
It consists of 7) an image output monitor, and (8) a recording device such as a VTR for registering the results of collection III. The optical discs used are write-once (WLO) optical discs that record information by drilling holes in the recording film, or magneto-optical discs that record and erase information using an underwater magnetized film as the recording film.
Mlo) disks are usually used for recording “
6" is a bit in the case of a W10 optical disc, and M10
In the case of a disk, they are called domains, but here they will be collectively called bits. The optical head 1 uses a semiconductor laser 9 as a light source.
It consists of an optical system that focuses the light emitted from the disk into a minute spot on the disk 10, and an access mechanism 11 that accesses the optical head 1 at high speed.

First, the recording process of one image signal and audio signal will be explained. The external input terminals 12 include a video input terminal 121, a still image input terminal 122. There is an audio input terminal 123, a video input terminal 121. The still image input terminal 122 receives image signals from image information sources such as VTRs, video cameras, optical video discs, and animation videos, and the audio input terminal 123 receives audio signals and audio signals accompanying the image signals. Audio signals such as narration and 80M music are input. In the case of a # image, the image signal is guided to the FM modulation circuit 31, passes through SW1 for switching between moving images/still images, and SW2 for switching between recording/playback images, and is led to the image output monitor 7 to display the image. Furthermore, the audio signals accompanying the moving image are simultaneously inputted from the audio input terminal 123, and after being selected by the SW3 for switching between moving image/still image and other audio, they are led to the FM modulation circuit 31 and subjected to the process described above. Modulated by

In the case of a still image, the image signal is selected by SWI and SW2, displayed on the image output monitor 7, and sent to the front stage of the digital modulation/demodulation circuit 4 via SW4, which switches between a still image during recording and a moving image during playback. After being input to a certain frame memory 41 and compressed, an error correction code (FC
C) is added and digitally modulated. The audio signal is first selected by SW5, which switches audio during recording/playback, and guided to the speaker 8, and still image and other audio is selected by SW3, and guided to the audio processing circuit 5, where it is processed through the process described above. Modulated.

The switches for selecting each condition are switched by the controller 18. The modulation signals pulsed by the respective modulation circuits are input to the semiconductor laser drive circuit 13, which causes the semiconductor laser 9 to emit high-output pulses to generate optical discs. Form a bit on 10. Due to the relationship between the recording frequency and the required S/N, the recording area on the optical disc 10 is arranged such that moving images are placed outward from the center, still images are placed inward from the center, and audio signals are placed on the innermost circumference. Corresponding address information is recorded on each track so that it can be recorded by random access.1 For example, in the case of a video, NTSC signals are recorded using T'M modulation, so the address information is placed within the vertical synchronization period. However, since still images and audio are digital signals, information is recorded in this area in units of sectors, and an ID section is provided at the beginning of each sector as a track divided into multiple sectors. Place address information in . Furthermore, address management information for indicating the recording position of the recorded pig is preferably recorded on a control track provided on the inner or outer circumference. 3001, track pitch 1.6μm
, the disk rotation speed is 18 Orpm, and the radius of the entire recording area is 7.
If it is 70m (0~140+m), 1 frame/1 track is required to record 20 minutes of video, so the number of required tracks is 20x60x30=36000 tracks, and the recording area at that time is 1.6μmx3600.
0 = 57.6 cabinets. In addition, in the case of still images, the maximum amount of data after compression for one screen is 118 bytes, and if the number of sectors per track is 60 and the user data per sector is IK bytes, then the maximum amount of data after compression for one screen is 2 tracks. becomes. If the number of still images is 1000, the required number of tracks will be 20oO tracks, and the recording area will be 1.
．． 6μm×2000=3.2m. Therefore, the areas given for audio information are 70-56, 7-3,
2=10 cabinets, the number of tracks is 10m/1.6μm=
6250 truck.

The audio capacity at this time is 6250 x 60 = 375 Mbytes, and the effective transfer rate is 2 Mbit/s (0,2
5 Mbytes/sec), so 375 Mbytes/(0,2
5MBytes/sec) = 1500 seconds = 25 minutes.
The process of reproducing from an optical disc will be explained. Light emitted from the optical head 1 is reflected by the optical disk 10, and a reflected signal that changes depending on the presence or absence of bits on the track is sent to the photodetector 1.
By detecting at step 4, a reproduced signal is obtained. After the reproduced signal is amplified by the head amplifier 15, the signal is demodulated by the aforementioned process in a processing system corresponding to each signal. When accessing the optical head 1, the address information included in each demodulated signal detected by the ID recognition circuit 16 is compared with the address information specified from the higher-level controller 18 for editing, and the addresses match. This is performed by driving the access mechanism 11 with the access circuit 2 in the same way. To play a video, control 1
8, the optical head 1 accesses the area (A) of the optical disc 10 to read information. The moving image reproduced by the FM demodulation circuit 32 is selected by the moving image/still image selection SW 6,
Furthermore, it is switched by the recording/playback image switching SW2 and displayed on the image output monitor 7, and the VT for editing.
The signal is input to R17 (for example, a digital VTR). Further, after the audio for the moving image is separated from the image in the FM demodulation circuit 32, switching SW7 is made to switch between the audio and the audio from the audio processing circuit 5.
．． Furthermore, the speaker 8 is connected via the recording/playback switching SW5.
At the same time, the user is guided to the VTR 17 for editing. When reproducing a still image, the optical head 1 accesses area (B) on the optical disk 10 and reads out information.The original still image is reproduced by the digital demodulation circuit 4 and sent out through the frame memory 41. The output is the same as the video with SW6. The image is displayed on the monitor through the SW 2 and is led to the VTR 17 for editing. To play audio explaining a still image or other audio, move the optical head 1 to the optical disc 10 during playback.
The audio reproduced by the audio processing circuit 5, which accesses the area (C) above and reads information, is processed by SW7. SW
5 to a speaker 8 and a VTR 17 for editing. Also.

In image editing, moving images and still images may be repeatedly played back, and when playing back with one optical head, processing during access becomes a problem. In order to solve this problem, a frame memory 41 provided in the digital modulation/demodulation circuit 4 for still images is used, and during access, the screen immediately before the start of access is stored in the frame memory 41 and played back.
Screen switching can be made smoother. For this purpose, 8w4 is provided to switch between still images during recording and moving images during playback, and analog/digital (A/D) is used for moving images.
After conversion, the still image side is selected by SW6 in order to store the image in the frame memory 41 and simultaneously perform digital/analog (D/A) conversion and send it out as a still image. Furthermore, in order to make screen switching smoother, it is necessary to achieve an access time of 60 ms or less, which is the reaction time of the human eye.

The movement of the optical head and the use of the frame memory will be explained with reference to FIG. 6 regarding an example of editing. First, let's start with a still image showing, for example, a title. The optical head moves to the still image area (
B), and this content is stored in the frame memory.In order to reproduce the audio for the narration, the optical head moves to the audio area (C) and executes it. When this is completed, the optical head accesses the moving image area (A) for moving image reproduction. The contents of the frame memory are stored with still image data of 9 yen until the positioning of the optical head in the moving image area is completed.

Next, when playback of the moving image begins, the image display and the information sent to the editing VTR are switched from the contents of the frame memory to the moving image (with audio). The optical head accesses the still image area (B) again to reproduce the still image. At this time, the image immediately before the optical head starts accessing is multiplied by N in the frame memory, and the optical head is moved to the still image area (B
) and then switch to the still image content. From now on, this operation will be repeated.

As described above, the apparatus can be simplified by arranging image information and audio information on the same optical disk and recording and reproducing them using one optical head.

〔Effect of the invention〕

According to the present invention, moving images, still images, and accompanying audio signals are recorded as video information on the same optical disk, taking into consideration their respective frequency characteristics, and are accessed repeatedly at high speed using a single optical head. The device can be simplified by reproducing the data while the data is being played.

[Brief explanation of the drawing]

FIG. 1 is a diagram illustrating an embodiment of the optical disc of the present invention;
Figure 2, Figure 3, Figure 41! [, Fig. 5 is a diagram for explaining the present invention in detail, Fig. 6 is a diagram for explaining the present invention] Figure <a)

Claims (1)

[Claims] 1. A light source, an optical system that guides the light emitted from the light source to an information recording medium, and an optical head that reads information from the information recording medium, An optical disc processing device characterized in that an audio signal accompanying the audio signal is recorded in separate areas, and an image is edited while accessing each area with a single optical head. 2. The optical disk processing apparatus according to claim 1, wherein a moving image, a still image, and an accompanying audio signal are recorded on the information recording medium in this order from the outside. 3. The optical disk processing apparatus according to claim 1, wherein moving images are recorded on the information recording medium using analog signals, and still images and audio signals associated therewith are recorded using digital signals. 4. The optical disk processing apparatus according to claim 1, wherein the image data immediately before access is taken into the frame memory, and the image data is stored in the frame memory until the next information is read by access. 5. The optical disk processing apparatus according to claim 1, wherein the access time of the optical head is 60 ms or less.