JPH1166741A - Information recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent irregularities in an image and a sound due to changing recording modes and a mechanical transient phernomenon and to obtain the stable image and sound by calculating a bit rate value of an encoder in advance from a recording time value and a recordable capacity value of a storage medium and performing recording at a constant bit rate value. SOLUTION: The recordable capacity value calculated from an FAT(file allocation table) of the recording medium 9 and the recording time value from an operating part 2 are stored in a memory 4. The recordable capacity value is divided by the recording time value, and its quotient is set in a bit rate setting part 5 by an MPU(microprocessing unit) 1. Recording is started up by pressing a picture recording button, and an input signal 11 is inputted to the encoder 6, and after compression processing, the signal 11 is recorded in the recording medium 9 by a recording and reproducing part 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an information recording / reproducing apparatus, and more particularly to an information recording / reproducing apparatus for compressing and recording information.

[0002]

2. Description of the Related Art As a device for recording and reproducing video and audio information, a video tape recorder (hereinafter abbreviated as VTR) is common and widely used. However, when recording video / audio information over a long period of time on a VTR, sometimes the recording area of the tape is used up before the recording is completed. was there. Various schemes have been proposed to avoid this situation. As an example, Japanese Patent Application Laid-Open No. 7-85529 is known as a method for avoiding a situation in which the recording area of the tape is used up before the recording is completed. This example calculates the recording time value and the remaining amount of tape, and switches the recording mode from the standard mode to the triple mode when the remaining tape amount becomes smaller than the remaining recording time value. there were.

[0003]

In the above-mentioned conventional system, when the recording mode is switched from the standard mode to the triple mode, there is no consideration to the disturbance of the image and the sound which occurs until the tape feed amount becomes stable. However, there is a problem that some important recorded contents become unclear.

In the above conventional method, there are only two types of recording modes, a standard mode and a triple mode, and there is a problem that recording cannot be performed for a recording time value longer than the triple mode.

It is an object of the present invention to calculate a bit rate value of an encoder for compressing information of an input signal in advance based on a recording time value and a recordable capacity value of a storage medium, and perform recording at a constant bit rate value. An object of the present invention is to provide an information recording / reproducing apparatus capable of obtaining stable images and sounds without disturbing images and sounds during reproduction.

It is a second object of the present invention to provide an information recording / reproducing apparatus capable of freely selecting a recording time value by allowing a bit rate value to be arbitrarily set.

[0007]

In order to achieve the above object, the present invention provides a method of dividing a bit rate value of an encoder for compressing information of an input signal into a value obtained by dividing a recordable capacity value of a storage medium by a recording time value. A means for setting is provided.

In order to achieve the second object, the present invention comprises means for arbitrarily setting a bit rate value of an encoder for compressing information of an input signal.

[0009]

FIG. 1 is a schematic diagram of the present invention. The storage medium may be a magnetic disk, an optical disk, or the like. In this example, the storage medium is an optical disk. Hereinafter, the schematic configuration will be described, and a Micro Processing Unit 1 (hereinafter abbreviated as MPU1) for controlling the entire apparatus.
An operation unit 2 for inputting various operations; a display unit 3 for displaying various information of the apparatus; a memory 4 used for calculation and storage of information; an encoder 6 for compressing information of an input signal; A bit rate setting unit 5 for setting a bit rate value; a recording / reproducing unit 7 for writing information to or reading information from a storage medium; a disk drive unit 8 for controlling rotation of the storage medium; And a decoder 10 for expanding the compressed information read from the storage medium 9 to the recording / reproducing unit 7. Input signal 1
1 indicates a signal to be recorded, and the output signal 12 indicates a reproduced signal. The address / data bus 13 controls the entire apparatus.

In the present embodiment, the bit rate value of the encoder 6 for compressing the information of the video and audio signals as the input signals is represented by
The bit rate value of the encoder 6 can be freely changed by setting the bit rate setting unit 5 from the MPU 1. By utilizing this, a value obtained by dividing the recordable capacity value of the storage medium 9 by the recording time value is set as the bit rate value of the encoder 6. In addition, by making the bit rate value of the encoder 6 arbitrarily configurable, it is possible to relatively freely change the recordable time and the image quality and sound quality of the recording signal. The feature is that it is possible to select whether to make settings or give priority to image quality and sound quality. However, in this case, the meaning of “prioritize image / sound quality” does not necessarily mean that good image / sound quality is obtained by increasing the bit rate value, but also includes the case where bad image / sound quality is selected. Means that the image quality and the sound quality are set with priority over the recording time value. Hereinafter, the schematic operation of this embodiment will be described with reference to FIGS.

Prior to the description of recording / reproduction, the contents displayed on the display unit 3 and the operation method of the operation unit 2 will be described in advance. FIG.
3 shows details of the display unit 3 of the present embodiment, and FIG. 3 shows details of the operation unit 2. The display unit 3 has different meanings in the case of recording and in the case of reproduction, and will be separately described. First, the meaning of FIG. 2 when performing recording will be described. The calendar section 22 indicates the current date and time. The message section 23 is a display field for a memo so that the recorded contents can be immediately understood later. The disk capacity section 24 indicates how much recordable part is in the disk. The recording time section 25 indicates the amount of time to be recorded, the bit rate section 26 indicates the bit rate value to be set in the encoder 6,
The light emitting diode on the left of each indicates the recording time setting mode or the image quality / sound quality setting mode. Next, the meaning of FIG. 2 when performing reproduction will be described. The calendar section 22 indicates the date and time when the information was recorded. The message section 23 indicates the contents of a memo indicating the recorded contents. The disk capacity section 24 indicates how much recordable part exists in the disk as in the case of recording. The recording time section 25 indicates the amount of time the information was recorded, the bit rate section 26 indicates the bit rate value when the information was recorded, and the light emitting diodes on the left of each indicate that the information was recorded in the recording time setting mode. Indicates whether the recording was performed in the image quality / sound quality setting mode. Turning to FIG. 3, the time / image quality button 32 is used when selecting the recording time setting mode or the image quality / sound quality setting mode.
The calendar button 33 is used together with the UP / DOWN button 36 when correcting the date, the clock button 34 is used when correcting the time, and the message button 35 is used when inserting a message. The reverse playback button 37, the stop button 38, the playback button 39, the recording button 40, and the fast-forward button 41 are used to realize their respective functions, and each button has a light emitting diode. Since it is embedded, the current operating state can be known.

The recording / reproduction will be described with reference to FIGS. 1, 2 and 3. First, the storage medium 9 to be recorded is mounted on the disk drive unit 8. In this storage medium 9, a file allocation table (hereinafter abbreviated as FAT) indicating an internal recording state is written.
After reading the FAT of the storage medium 9 through the recording / reproducing unit 7, the MPU 1 converts the recordable capacity value into “MBit (megabits)” and stores it in the memory 4. When the operator presses the time side of the time / image quality button 32 from the operation unit 2 (enters a recording time setting mode) and sets a desired recording time value on the storage medium 9 with the UP / DOWN button 36, the display unit 3 Of the MPU 1
Converts the recording time value into units of "seconds" and stores the same in the memory 4 as well. Subsequently, the MPU 1 calculates the bit rate value “MBPS (megabits / second)” of the encoder 6 by dividing the recordable capacity value stored in the memory 4 by the recording time value, and displays it on the bit rate unit 26. At the same time, it is set in the bit rate setting unit 5. This process will be described below by applying specific numerical values.

(1) If the recording time value is 1 hour and 50 minutes, the value stored in the memory 4 is converted to “seconds” and 660
0 seconds.

(2) The recordable capacity value of the storage medium 9 is 27
If it is 00 “MByte”, the value stored in the memory 4 is multiplied by 8 and converted into “MBit”, and 21600 “MBit”
it ".

(3) 2600 “MBit” is converted to 6600
Divide by "seconds" to get 3.2727 "MBPS".

(4) The actual value set in the bit rate setting section 5 is set to, for example, 3.2 "MBPS" with a margin, and the same value is displayed in the bit rate section 26.

(5) Thus, if 6600 “seconds” are added to 3.2 “MBPS”, then 21120 “MBit”
Thus, recording can be performed with a margin of about 2% with respect to the recordable capacity value of the storage medium 9.

At this time, if necessary, various messages can be inserted according to the contents of the recording information and the like, and used for later retrieval of the recording information. In addition, the recording start time and the recording time value are automatically set to FAT together with the message.
Recorded in the information. Thus, the preparation for recording is completed. After that, the recording is started by pressing the recording button 40 of the operation unit 2. When recording is started, an image / audio signal, which is an input signal, is input to an encoder 6, encoded at a predetermined bit rate value, subjected to a compression process, sent to a recording / reproducing unit 7 and sent to a recording medium 9. Will be recorded. When the recording for the set recording time value is completed, the MPU 1
Turn off the light emitting diode of the recording button 40 of the operation unit 2,
Inform the operator that the recording is completed.

Next, an example of reproducing information recorded on the storage medium 9 will be described. First, by attaching the storage medium 9 to be reproduced to the present apparatus, the information in the storage medium 9 can be immediately confirmed. That is, the MPU 1 that has detected that the storage medium 9 has been mounted reads the FAT through the recording / reproducing unit 7, displays the recording information in the storage medium 9 on the display unit 3, and determines which recording information is to be read by the operator U.
It waits for selection and instruction by the P / DOWN button 36. For example, in order to reproduce the information recorded above, the recording date and time, the recording time value, the message of the recorded content, and the like of each information displayed on the display unit 3 are checked, and then the reproduction button 39 is pressed. In response, the MPU 1 sets the F of the designated recording information.
With reference to the AT, the read information read based on the AT is sequentially transferred to a decoder, the compressed and recorded information is decompressed, extracted as an output signal 12 converted into an image / audio signal, and displayed on a television monitor or the like. Do.

Next, a case where the bit rate value of the encoder 6 is arbitrarily set and recording is performed in the image quality / sound quality priority mode will be described. Note that the description will be repeated for many parts of the above example, and thus description thereof will be omitted. First, in this example, when the storage medium 9 to be recorded is mounted on the disk drive unit 8, the MPU 1
After reading T, the recordable capacity value is converted to “MBit (megabit)”, displayed on the disk capacity unit 24 and stored in the memory 4. Next, time / image quality button 3
When the operator sets the desired bit rate value “MBPS (megabits / second)” using the UP / DOWN button 36, the MPU 1 saves this value in a memory, and the bit rate setting unit 5 Also set. Furthermore, the recordable capacity value is divided by the bit rate value, converted into a recordable time (hours / minutes), and displayed on the recording time section 25 of the display unit 3. Here, if the bit rate value is set to a sufficiently low value, recording of an extremely long time that cannot be obtained by a VTR or the like can be performed although image quality and sound quality are deteriorated. Conversely, if the bit rate value is set to a sufficiently high value, it is possible to perform recording with better image quality and sound quality than VTR. Naturally, when a high bit rate value is set in pursuit of image quality and sound quality, a desired recording time value may not be satisfied depending on the recordable capacity value of the storage medium 9.

The subsequent recording / reproducing operations are the same as those in the recording time setting mode, and will not be described.

As another example, it is also possible to arbitrarily set both the recording time value and the bit rate value by setting each time / image quality button 32 after "pressing twice". It is. However, in this case, it is necessary that each set value is within the allowable range of the system, and the recordable capacity value, the recording time value,
The condition is that there is no inconsistency in the relationship between the bit rate values. If these conditions are satisfied, recording can be performed under any conditions.

As described above, according to the present invention, the bit rate value of the encoder is calculated from the recording time value and the recordable capacity value of the storage medium, and recording is performed at a constant bit rate value. This makes it possible to obtain stable images and sounds without any disturbance of the sound.

In addition, since the setting of the bit rate value to the encoder can be arbitrarily performed, the recording time value can be freely selected.

[0025]

According to the present invention, the bit rate value of the encoder is calculated in advance based on the recording time value and the recordable capacity value of the storage medium, and recording is performed at a constant bit rate value. Image and sound disturbances caused by changes in the
There is an effect that an information recording / reproducing apparatus capable of obtaining stable images and sounds can be provided.

Further, by setting the bit rate value of an encoder for compressing information of an input signal arbitrarily, it is possible to provide an information recording / reproducing apparatus capable of freely selecting a recording time value.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram of an information recording / reproducing apparatus showing an embodiment of the present invention.

FIG. 2 is a diagram showing details of a display unit in the embodiment of the present invention.

FIG. 3 is a diagram showing details of an operation unit in the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... MPU (Micro Processing Unit) 2 ... Operation part 3 ... Display part 4 ... Memory 5 ... Bit rate setting part 6 ... Encoder 7 ... Recording / playback part 8 ... Disk drive part 9 ... Storage medium 10 ... Decoder 11 ... Input signal 12 … Output signal 13… Address / data bus 22… Calendar section 23… Message section 24… Disk capacity section 25… Recording time section 26… Bit rate section 32… Time / picture quality button 33… Calendar button 34… Clock button 35… Message button 36 UP / DOWN button 37 Reverse play button 38 Stop button 39 Play button 40 Record button 41 Fast forward button

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Naoo Tanabe 1-280 Higashi-Koigakubo, Kokubunji-shi, Tokyo Inside the Central Research Laboratory, Hitachi, Ltd. (72) Inventor Taizo Kinoshita 1-280 Higashi-Koikekubo, Kokubunji-shi, Tokyo Hitachi, Ltd. In Central Research Laboratory (72) Inventor Hiroshi Yoshiki 1-280 Higashi Koikekubo, Kokubunji, Tokyo, Japan Inside Central Research Laboratory, Hitachi, Ltd. (72) Inventor Akihiko Oba 1-280 Higashi Koikebo, Higashi Koikekubo, Kokubunji, Tokyo, Japan In Central Research Laboratory, Hitachi, Ltd. 72) Inventor Tohru Matsushita 1-280 Higashi Koigakubo, Kokubunji-shi, Tokyo Inside the Central Research Laboratory, Hitachi, Ltd.

Claims (2)

[Claims] An MPU for controlling the entire apparatus, an operation section for inputting various operations, a display section for displaying a state of the apparatus, a memory used for calculation and storage of information, and an encoder for compressing an input signal to information A bit rate setting unit for setting a bit rate value of the encoder; a recording / reproducing unit for writing information to a storage medium or reading information from the storage medium; and a decompression process for compressed information read from the recording / reproducing unit. An information recording / reproducing apparatus having a decoder unit, wherein the bit rate value of the encoder is set to a value obtained by dividing a recordable capacity value of the storage medium by a recording time value. 2. The information recording / reproducing apparatus according to claim 1, wherein a bit rate value of an encoder for compressing information of an input signal can be arbitrarily set.