JP3893347B2 - Disc recording / playback device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a disk recording / reproducing apparatus using a disk-shaped recording medium such as an optical disk, a magneto-optical disk, or a hard disk as a recording medium.
[0002]
[Prior art]
For example, when image data is being recorded on a disk-shaped recording medium such as an optical disk, new data can be recorded continuously without erasing the recorded data when there is no more or less free space. The related art described above is known (see Patent Document 1).
[0003]
In this prior art, when the remaining amount of disk (free space) falls below a predetermined value, in parallel with the recording of new data (the operation of encoding and recording new data that has been input), The recorded data is reproduced from the disc, the reproduced data is re-encoded to low-rate compressed data by the re-encoding means, and then re-recorded to increase the free space.
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 11-167770
[Problems to be solved by the invention]
However, in the prior art described in Patent Document 1, consideration is given to arranging the re-encoded and re-recorded data and the newly recorded data in time series on the disc. Therefore, the data re-encoded and re-recorded and the newly recorded data are scattered or mixed on the disc. In this way, when the re-recorded data and newly recorded data are not time-sequentially continuous on the disc, it can be played back at a normal speed, but the rotation of the disc is more than double speed. In some cases, it may be difficult to pick up data depending on seek time. Further, even when performing a high-speed search, there is a concern that seek time may become a bottleneck in speeding up the disk rotation speed if data is recorded on the disk at different times.
[0006]
Furthermore, in the prior art described in Patent Document 1, since the recording rate of the re-recorded data and the newly recorded data is different, there is a problem that the image quality changes during reproduction and the user feels uncomfortable. .
[0007]
The present invention has been made in view of the above points, and an object of the present invention is to erase recorded data when there is no more free space in the middle of recording data on a disk-shaped recording medium. In a disc recording / reproducing apparatus capable of continuously recording new data, high-speed reproduction and high-speed search can be easily and reliably achieved. In addition, an object of the present invention is to prevent a sense of incongruity due to a change in image quality during reproduction by making the recording rate of reproduced and re-recorded data and newly recorded data the same. Is to make it.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, a disc recording / reproducing apparatus according to the present invention provides:
Recording means for recording data on a disk-shaped recording medium;
A first buffer memory for temporarily storing input new recording data;
Reproducing means for reproducing data recorded on the disc-shaped recording medium;
A decoder for decoding the reproduced data;
A second buffer memory for temporarily storing decoded reproduction data;
An encoder that encodes data stored in the first buffer memory or the second buffer memory and outputs the encoded data to the recording means;
A recording rate calculation means for calculating a recording rate based on an instruction to extend the recording time of the disc-shaped recording medium in the middle of input of new recording data, and instructing the encoder to the determined recording rate;
Based on the instruction to extend the recording time, the data to be reproduced is instructed and reproduced, and the data stored in the first buffer memory and the second buffer memory are selectively switched to form a disk. Control means for controlling the recording on the recording medium;
Prepared,
According to the recording rate obtained based on the instruction to extend the recording time , the control means repositions the recorded data for each predetermined small data unit and predetermined small data on the disk-shaped recording medium. The recording position of the new data for each unit is determined, and the recording of the new data in the predetermined small data unit and the recording of the predetermined small data unit according to the recording rate obtained based on the instruction to extend the recording time. Relocation recording of the recorded data in the predetermined small data unit necessary for recording new data, and rearrangement recording of the recorded data in the predetermined small data unit required by the result of the rearrangement recording, and are sequentially executed, on the disk-shaped recording medium, such re-recorded date and the newly recorded data chronologically successive to control playback / recording, structure It is.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0010]
FIG. 1 is a block diagram showing the configuration of a disk recording / reproducing apparatus according to an embodiment of the present invention. This embodiment uses an optical disk as a recording medium and has dedicated pickups for recording and reproduction, respectively. This is an application example.
[0011]
In FIG. 1, 1 is a recording time extension control circuit that functions as a main control unit, and 2 is a first buffer that temporarily stores new recording data (here, digitized image data) input from the outside. The memory 3 is an encoder that compresses data to be recorded in a format such as MPEG2, and 4 is an appropriate conversion process (modulation, ECC encoding, etc.) for disk recording on data output from the encoder 3. A recording data processing circuit 5 is a recording pickup for recording data output from the recording data processing circuit 4 on a disk, 6 is a reproduction pickup for reproducing data recorded on the disk, and 7 is reproduced from the disk. A reproduction data processing circuit for converting data into data before passing through the recording data processing circuit 4 (demodulation, ECC decoding, etc.), 8 A decoder 9 that decompresses the data output from the reproduction data processing circuit 7 in a format such as MPEG2 and restores the original digitized image data; a recording pickup 5 that seeks together and a reproduction It is a pickup drive circuit that controls the position of the pickup 6.
[0012]
In the recording time extension control circuit (main control unit) 1, 11 is a second buffer memory for temporarily storing data decoded by the decoder 8, and 12 is data stored in the first buffer memory 2. And a switch that selectively switches between the data stored in the second buffer memory 11 and outputs it to the encoder 3, and 13 calculates a recording rate of the data to be recorded and instructs the encoder 3 to calculate the recording rate. A circuit 14 has a function of calculating an address on a disk to be recorded or reproduced, and is a disk address control circuit for sending a command to each unit to control recording / reproduction. The disk address control circuit 14 controls the pickup drive circuit 9 to control the position of the pickups 5 and 6 in the disk radial direction, and controls the on / off control of the recording data processing circuit 4 and the reproduction data processing circuit 7. Perform on / off control. Further, the disk address control circuit 14 performs switching control of the switch 12.
[0013]
Here, the recording time extension control circuit 1 is configured as a high-order control circuit (main control unit) for controlling recording / reproduction, and the recording rate calculation circuit 13 of the recording time extension control circuit 1 and the disk address control. The circuit 14 and the like are actually embodied by a CPU and software executed by the CPU. Of course, the entire recording time extension control circuit 1 can be constructed by hardware.
[0014]
The first buffer memory 2 and the second buffer memory 11 can be constructed with the same memory element.
[0015]
In the configuration shown in FIG. 1, for normal recording, the recording rate calculation circuit 13 gives a command to the encoder 3 so that the normal recording rate is obtained, and the disk address control circuit 14 sets the switch 12 to the first recording rate. The buffer memory 2 side is maintained in the selected state. On the other hand, when a command for instructing to extend the disc recording time is received by the user during normal recording (information on the recording time to be increased, or the entire recording time from an extension time input unit (not shown)). When the information on how long the recording time is to be reached), the recording rate calculation circuit 13 records the recording rate corresponding to the desired total recording time of the disc (current recording time of the disc + recording time to be increased). And gives a command to the encoder 3 to perform compression processing at the obtained recording rate. When the user gives an instruction to extend the disc recording time, as will be described in detail later, the disc address control circuit 14 reproduces the data already recorded on the disc and the first buffer memory 2. In order to perform selective recording processing of the data stored in the second buffer memory 11 or the data stored in the second buffer memory 11, the position control of the pickups 5 and 6 via the pickup driving circuit 9 and the address to be reproduced or recorded And the on / off control of the recording data processing circuit 4 and the reproduction data processing circuit 7 for reproducing or recording the data corresponding to the address, and the selective switching control of the switch 12.
[0016]
Next, the operation of this embodiment will be described. When new image data input from the outside is normally recorded on the disc, that is, when the normal recording time is set as the recording time of the disc (in this case, the user must be aware of it) As described above, the switch 12 is in the state of selecting the first buffer memory 2 side. At this time, the image data input from the outside is encoded by the encoder 3 through the first buffer memory 2 and the switch 12, and further converted into recording data by the recording data processing circuit 4, and then the recording pickup. 5 is recorded on the disc.
[0017]
FIG. 2 shows a recordable area 22 on the disk 21, and during normal recording, data is transferred from the recording start point A on the inner circumference side to the recording end point B on the outer circumference side. It is recorded sequentially on each track.
[0018]
FIG. 3 is a diagram showing a state near the recording start point A in FIG. FIG. 3A shows a state at the time of recording at a fixed bit rate, and the data recorded in units of GOP (Group Of Pictures) are equal in length on the track of each GOP. . FIG. 3B shows a state at the time of variable bit rate recording, and data recorded in GOP units has non-uniform lengths on the tracks of each GOP. The present invention can be applied to both such fixed bit rate recording and variable bit rate recording.
[0019]
Next, the operation when the user gives an instruction to extend the disc recording time during normal recording will be described. When the normal recording is in progress, the user can recognize that the free space on the disk has been reduced by displaying an alarm message on the display. In addition to the recording time, enter the recording time you want to increase or the total recording time after the increase (Note that the device automatically sets the appropriate increase time when the free disk space runs out or decreases. It is also possible to do so).
[0020]
For example, the conditions during normal recording are: recording rate: 10 Mbps, 1 GOP: 30 frames (image data for 1 second), maximum recording time: 60 minutes, total GOP number: 3600, When the recording time is instructed to be doubled, the recording conditions are as follows: recording rate: 5 Mbps (half the original recording rate), 1 GOP: 30 frames (image data for one second), maximum recording time: 120 minutes The total number of GOPs is 7200.
[0021]
FIG. 4 (a) shows the relationship between the recording position No on the disc before the recording time extension and the relative recording time corresponding thereto, and in the original recording state, when full recording is performed, recording on the innermost circumference of the disc is performed. Recording positions D1 to D60 are assigned from the start point A to the recording end point B on the outermost circumference of the disc, and data (GOP1 to GOP3600) are recorded at 10 Mbps here.
[0022]
FIG. 4B shows the relationship between the recording position No on the disc after the recording time has been extended and the relative recording time corresponding to the recording time. As a result of setting the recording time to double 120 minutes, the recording start point is shown. When the recording position from A to the recording end point B is reset as D1 to D120 and full recording is performed, data (GOP1 to GOP7200) is recorded at 5 Mbps from the recording position D1 to the recording position D120. .
[0023]
The present invention makes it possible to extend the recording time from the state of FIG. 4 (a) to the state of FIG. 4 (b), for example, when the image data recorded on the disc is fully recorded. , GOP1 to GOP7200 are recorded so as to be continuous in time.
[0024]
For convenience of explanation, assuming that full recording is performed in the state of FIG. 4A, in the present invention, the original data D1 recording position data (GOP1) is the recording position of FIG. 4B. The recording rate is reduced to half the recording rate at the position D1 (at a recording rate of 5 Mbps), and the original D60 recording position data (GOP3600) is recorded at the recording position D60 in FIG. 4B. Is recorded in half (at a recording rate of 5 Mbps), and the first data (GOP 3601) of new recording data is recorded at a recording rate of 5 Mbps at a position immediately after the recording position D60 in FIG. Will be.
[0025]
In this embodiment, the recording rate is reduced by reproducing the data from the disc in order to perform the rearrangement of the recorded data without any time trouble while recording the new input image data. An operation of re-recording later and an operation of recording new data input are sequentially executed in units of 1 GOP. For example, when new GOP 3601 data is recorded, the operation of rearranging the GOP 1801 data at the recording position D30 in FIG. 4A at the recording position D30 in FIG. 4B and the new GOP 3601 data Is performed substantially in parallel with the operation of recording at a position immediately after the recording position D60 in FIG. In addition to this, as a result of rearranging the data of the GOP 1801 at the recording position D30 in FIG. 4A at the recording position D30 in FIG. 4B, the data from the recording position D15 in FIG. The operation of rearranging the GOP 901 data that must be moved to the recording position D15 in FIG. 4B, and the GOP 901 data in the recording position D15 in FIG. 4) is rearranged at the recording position D15 in FIG. 4A, the GOP 451 data that must be moved from the recording position D15 / 2 in FIG. 4A is rearranged at the recording position D15 / 2 in FIG. 4B. As a result of rearranging the operation and the GOP 451 data at the recording position D15 / 2 in FIG. 4A at the recording position D15 / 2 in FIG. 4B, the recording position in FIG. If you do not move from D15 / 4 The operation of rearranging the data recorded on the disk in units of 1 GOP in a so-called ball-throw manner, for example, the operation of rearranging the GOP 226 data not to be recorded at the recording position D15 / 4 in FIG. The data before being reproduced from the disc and re-recorded (rearranged) is temporarily stored in the second buffer 11.
[0026]
In order to perform the recording of the new image data and the rearrangement of the recorded data as described above, the recording time extension control circuit (main control unit) 1 is a recording rate calculation circuit as described above. In step 13, a recording rate corresponding to the total recording time of the disc desired by the user is calculated, and a command is given to the encoder 3 to perform compression processing at the determined recording rate. Further, the recording time extension control circuit (main control unit) 1 uses the disk address control circuit 14 to record the data of all GOP data arranged on the disk based on the information on the total recording time of the disk desired by the user. An address is calculated and a disk address is assigned to each GOP. The disc address control circuit 14 is under the control of a host controller (not shown) in the recording time extension control circuit (main control unit) 1, the pickup drive circuit 9, the recording data processing circuit 4, and the reproduction data processing circuit 7. In addition, by controlling the operation of the switch 12, the re-recording of data reproduced from the disk and the recording of new data are sequentially performed in units of 1 GOP, and the re-recorded date and new data are recorded on the disk. Playback / recording is controlled so that the data is continuous in time series.
[0027]
FIG. 5 is a schematic diagram showing how data reproduced from a disc is re-recorded and new data is recorded, for the sake of simplicity. In the example shown in FIG. 5, when the data of D1 to D4 is recorded on the disk and there is no free space, the recording time of the disk is specified to be doubled, and the data of D1 to D8 is recorded on the disk. Is shown when the recording rate is reduced to half of the original. Here, the data of D1 to D8 are each 1 GOP data, and are new data to which the data of D5 to D8 is input.
[0028]
In FIG. 5, a reproduction operation (reproduction is indicated by R in the drawing) and a recording operation (recording operation is indicated by W) are performed in the order of the arrows from the start state indicated by S. In FIG. 5, memory data in parentheses indicates data that is reproduced from the disk and temporarily stored in the second buffer memory 11, and as shown in FIG. 5, data D1 to D4 are stored from the disk. The data of D1 to D8 are recorded so as to be continuously arranged in time at a recording rate reduced to half of the original recording rate while sequentially reading each to make a free space.
[0029]
Note that the operation content shown in FIG. 5 is merely an example, and depending on the time of data reproduction, data recording, data compression (encoding), for example, new recording data D5 and D6 can be recorded almost simultaneously, Alternatively, it is possible in some cases to reproduce the data D3 and record the data D5 almost simultaneously.
[0030]
As described above, in this embodiment, the recording of new recording data and the re-recording of the read data are controlled in units of 1 GOP, so that the necessary buffer memory is also 2 GOP (20 Mbps) + α (variable bit rate) Since the above-described control can be performed if the memory has a capacity for absorbing the difference between the GOP data amount at the time of recording and the GOP data amount at the time of recording, and for temporarily storing new recording data, etc., consumer AV equipment In addition, even a general installed memory (SDRAM) capacity of about 128 Mbit for a personal computer can be realized sufficiently, and it is not necessary to add a large-capacity and expensive buffer memory, and the cost performance is excellent.
[0031]
FIG. 6 is a block diagram showing a configuration of a disk recording / reproducing apparatus according to another embodiment of the present invention. This embodiment is an example applied to an apparatus using a hard disk as a recording medium. In FIG. 6, reference numeral 10 denotes a recording / reproducing pickup composed of a magnetic head, and performs the same operation as that of the above-described embodiment of FIG. 1 except that the recording and reproducing heads are shared.
[0032]
【The invention's effect】
As described above, according to the present invention, when data is being recorded on a disk-shaped recording medium, new data is continuously recorded without erasing the recorded data when there is no free space. In a disc recording / playback device that enables recording, re-recorded data and newly recorded data are recorded so as to be continuous in time without interruption, so that high-speed playback and high-speed search can be realized easily and reliably. It becomes possible. In addition, since the recording rate of the data reproduced and re-recorded is the same as the newly recorded data, there is no sense of incongruity due to a change in image quality during the reproduction. In addition, since control is performed in units of 1 GOP, control can be realized even if a consumer AV device or a general installed memory for a personal computer is used as a buffer memory, and the cost performance is excellent. be able to. In addition, since the user gives an instruction to extend the recording time, the user can give an instruction for an appropriate extension time.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a main configuration of a disc recording / reproducing apparatus according to an embodiment of the present invention.
FIG. 2 is an explanatory diagram showing a recordable area, a recording start point A, and a recording end point B on a disc.
3 is an explanatory diagram showing a state at the time of recording at a fixed bit rate and a state at the time of recording at a variable bit rate in the vicinity of the recording start point A in FIG.
FIG. 4 is an explanatory diagram schematically showing a state before rearrangement and a state after rearrangement when the recording time of the disc is doubled in the embodiment of the present invention.
FIG. 5 is an explanatory diagram showing, in a very simplified manner, how re-recording of data reproduced from a disc and recording of new data are performed in an embodiment of the present invention.
FIG. 6 is a block diagram showing a main configuration of a disc recording / reproducing apparatus according to another embodiment of the present invention.
[Explanation of symbols]
1 Recording time extension control circuit (main control unit)
2 First Buffer Memory 3 Encoder 4 Recording Data Processing Circuit 5 Recording Pickup 6 Playback Pickup 7 Playback Data Processing Circuit 8 Decoder 9 Pickup Drive Circuit 10 Recording / Playback Pickup 11 Second Buffer Memory 12 Switch 13 Recording Rate Calculation Circuit 14 Disk address control circuit

Claims (3)

Recording means for recording data on a disk-shaped recording medium;
A first buffer memory for temporarily storing input new recording data;
Reproducing means for reproducing data recorded on the disc-shaped recording medium;
A decoder for decoding the reproduced data;
A second buffer memory for temporarily storing decoded reproduction data;
An encoder that encodes data stored in the first buffer memory or the second buffer memory and outputs the encoded data to the recording means;
A recording rate calculation means for calculating a recording rate based on an instruction to extend the recording time of the disc-shaped recording medium in the course of input of new recording data, and instructing the obtained recording rate to the encoder;
Based on the instruction to extend the recording time, the data to be reproduced is instructed and reproduced, and the data stored in the first buffer memory and the second buffer memory is selectively switched to form a disk Control means for controlling the recording on the recording medium;
Prepared,
According to the recording rate obtained based on the instruction to extend the recording time , the control means repositions the recorded data and predetermined small data for each predetermined small data unit on the disc-shaped recording medium. The recording position of the new data for each unit is determined, and the recording of the new data in the predetermined small data unit and the recording of the predetermined small data unit according to the recording rate obtained based on the instruction to extend the recording time. Relocation recording of the recorded data in the predetermined small data unit necessary for recording new data, and rearrangement recording of the recorded data in the predetermined small data unit required by the result of the rearrangement recording, wherein, by sequentially executing, on a disc-shaped recording medium, such re-recorded date and the newly recorded data chronologically successive to control playback / recording Disk recording and reproducing apparatus to be. In claim 1,
A disc recording / reproducing apparatus characterized in that a compression / decompression method handled by the encoder and the decoder is an MPEG method, and the predetermined small data unit is 1 GOP (Group Of Pictures). In claim 1,
A disc recording / reproducing apparatus characterized in that an instruction to extend the recording time of the disc-shaped recording medium is made by a user.

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