JP2006338699A - Data reproducing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a data reproducing device capable of reproducing recorded data from a recording medium comprising a plurality of clusters where the clusters to be used for data recording can be traced without lowering a reproducing speed in a tracing direction which is opposite to a data recording direction and capable of dispensing with specific constitution of a recording medium and a means and a device for reproducing data. <P>SOLUTION: A memory means 7 prepares an order opposite to a direction of an order for using clusters for data recording from the recording medium 17 and a control means 6 controls DSP 5 so as to reproduce data in the opposite order. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a data reproducing apparatus that reads out and reproduces data from a recording medium such as a semiconductor memory or a disk type memory.
In particular, when the data recording area is divided into a plurality of clusters and the data to be recorded is larger than the recording size of the clusters, the combination obtained by associating and combining two or more clusters. When data is recorded on a recording medium configured to record data in units of files in the cluster, data reproduction from the recording medium having such a configuration in a direction opposite to the direction in which the data was recorded, so-called The present invention relates to a playback device that performs backward playback.

In recording data on a recording medium, the amount of data to be recorded has increased and the capacity of the recording medium has increased with the increase in recording time and the quality of reproduced content. .
Therefore, today, in order to easily access a large amount of data, an area for recording data is divided into a plurality of clusters, and if the capacity of data to be recorded is smaller than the capacity of the cluster, one cluster is used. On the other hand, in the case of a large size, a configuration is used in which recording (storage) is performed in units of files in a combined cluster obtained by associating two or more clusters, that is, a recording medium using a file system.

  Now, the amount of data to be recorded is large, the size of the data file becomes large, the number of clusters corresponding to the file becomes enormous, and the reproduction means reads the next cluster only in the forward direction. When data is recorded on a recording medium using a FAT (file allocation table) file system, the recorded data may be played back in the backward direction.

Here, considering the case of reproducing data from a recording medium in a backward direction using a conventional data reproduction apparatus having a well-known configuration, reproduction is performed by the process shown in the flowchart shown in FIG. Become.
That is, when the main power switch of the data reproducing apparatus is turned on and the function of reproducing data in the backward direction is started, the means for reproducing data in the data reproducing apparatus starts reading the address of the cluster serving as the start data of the track.

The address of the starting cluster obtained by this reading is temporarily recorded (buffered) in the memory means.
Subsequently, the controller of the data reproducing apparatus or the CPU of the recording medium determines whether or not the data is the data to be read out in correspondence with the backward reproduction order with respect to the cluster address temporarily recorded in the memory means. .

If it is determined that the cluster address temporarily recorded in the memory means is the address of the cluster related to the data to be read, the read data is reproduced.
Further, it is determined whether or not the amount of reproduction of the data in the backward direction from the recording medium is as set, and the reproduction of data is repeated from the reading process of the cluster address of the start data until the set amount of data is reproduced.

  On the other hand, when the control unit of the data reproducing apparatus or the CPU of the recording medium determines that the address of the cluster temporarily recorded in the memory unit is not the data to be read, it reads the address of the next cluster that is continuously arranged, By acquiring data for the cluster, reading to the next cluster is repeated until it is determined that the address of the cluster temporarily recorded in the memory means is the data to be read.

In the data reproducing apparatus having such a configuration of the cluster address reading process, the address of each cluster of the recording medium to be reproduced is searched one by one until the cluster to be read is found from the currently read cluster. Become.
However, since such a search requires a long time for the search, it is difficult to continuously reproduce data at the same speed as at the time of recording. The problem that it cannot be obtained occurs.

  Here, data is recorded on a recording medium adopting a file system, and the recorded data is reproduced in a direction opposite to the recording direction (reverse reproduction), and such a problem can be solved. A playback device is known from the following document.

JP 2001-338484 A

  The data reproducing apparatus described in Japanese Patent Laid-Open No. 2001-338484 searches data recorded on a recording medium in a reverse direction at high speed, that is, handles data in a direction opposite to the direction in which the data is recorded. In order to enable this, first and second storage units are provided in the FAT entry of the FAT area recording of the hard disk, which is a recording medium, a forward cluster chain is provided in the first storage unit, and a second storage unit is provided. Each of the cluster chains in the reverse direction is written to each other, and the FAT entry number written in the first storage unit is continuously followed when searching in the forward direction (when reproducing), and when searching in the reverse direction (when reproducing) In this method, the FAT entry numbers written in the second storage unit are continuously tracked.

According to such a method, the number of the file to be read can be obtained immediately and sequentially in the same way as in the forward reproduction, so that the search (reproduction) in the backward direction with respect to the data recording direction is performed in the forward direction. It can be done as fast as a search.
However, a normal recording medium has only one storage unit. In other words, since the first storage unit and the second storage unit are the same, it is disclosed in JP-A-2001-338484. There arises a problem that data cannot be normally reproduced by a data reproducing apparatus having another configuration with respect to a recording medium.
In addition, since the FAT entry number in the reverse direction is not recorded on a recording medium recorded by a data recording apparatus having another configuration, the original effect of the invention cannot be obtained. Arise.

  The present invention has been made in view of the above circumstances. When data recorded on a recording medium is reproduced in a backward direction opposite to the direction in which the data was recorded, the reproduction speed is increased. Therefore, it is possible to provide a data reproducing apparatus that can secure the recording medium without delay, and does not require a special configuration for the recording medium and the data reproducing means and apparatus.

  The present invention reads and stores the order of addresses of clusters or / and combined clusters used for data recording from a recording medium, and can rearrange them in an order reverse to the order of addresses obtained here. A data reproducing apparatus comprising means.

  The detailed configuration is obtained by dividing the area for recording data into a plurality of clusters, and when the data to be recorded is larger than the size of the cluster, two or more clusters are associated and combined. The data is recorded in units of files on a recording medium in which data is recorded in units of files in a combined cluster, and the order of cluster addresses used for recording the data is also recorded when data is recorded. Data reproducing means for reproducing recorded data from a recording medium configured to record, and addresses of clusters or / and coupled clusters used for data recording are read in the order of data recording from the recording medium configured as described above. Memory means capable of storing and reordering the data recording order of the addresses in the reverse order, and recording on the recording medium having the above structure When the recorded data is played back from the end toward the head, it is recorded on the recording medium at an address in the reverse order of the order in which the data was recorded on the recording medium, based on the stored contents of the memory means. A data reproducing apparatus comprising control means capable of controlling the reproducing means so as to reproduce the data.

  In the data reproducing apparatus having such a configuration, when performing backward reproduction in the direction opposite to the direction in which the data was recorded, the address in the order opposite to the data recording direction is obtained from the memory means, and the order in the reverse direction is obtained. Then, the control means controls so that the data reproducing means reproduces the data.

In the recording medium to be used by the data reproducing apparatus of the present invention, each cluster is distributed in the data recordable area of the recording medium. With such a configuration, each cluster can be used arbitrarily. The cluster is prevented from being destroyed due to the central use of a specific cluster, and an empty cluster from which data has been erased can be reused for other data recording.
In addition, when the data recording area is divided into a plurality of clusters and the data to be recorded is larger than the size of the cluster, a cluster of coupling obtained by associating and coupling two or more clusters. The data is recorded in units of files.

Therefore, a plurality of files are recorded on one recording medium, there are clusters that are not used for data recording, and there are clusters related to a specific file and clusters that are not used for data recording. Because they are in a mixed state, the cluster of each file is configured so that the order in which the data was recorded can be understood. If the address of the cluster located in the front of two consecutive clusters is known, the address of the cluster located later As can be seen, it is configured to be chained with a chain of addresses.
In the present invention, the memory means obtains the order of addresses in the opposite direction to the chain of addresses in the chain and reproduces data in accordance with the obtained order of addresses in the opposite direction.

  In the present invention, based on the order of the addresses of the clusters used for data recording, the memory means creates a reverse address order and reproduces the data in the reverse address order. Therefore, the time for finding the address of the cluster to be reproduced can be kept short, the backward reproduction can be performed at a high speed, and the means and apparatus for reproducing the configuration of the recording medium and the data are provided. Since no special configuration is required, the data reproducing apparatus is highly versatile.

The present invention will be described based on the best mode shown in the drawings. However, the present invention is not limited by this form.
The data reproducing apparatus 1 includes a microphone 2, an amplifier 3, an A / D converter 4, a digital signal processor 5 (hereinafter referred to as "DSP 5"), a control unit 6, a memory unit 7, a D / D An A converter 8, an amplifier 9, a speaker 10, an operation unit 11 and a display unit 12 are provided.

The microphone 2 inputs voice that is target data to be recorded, converts it into an analog signal, and outputs it.
The amplifier 3 is connected to the subsequent stage of the microphone 2 and, when receiving an analog signal of audio data from the microphone 2, processes the volume to a desired size.
The A / D converter 4 is connected to the subsequent stage of the amplifier 3, and when an analog signal processed to a desired size is input, the analog signal is converted into a digital signal and output.

When the DSP 5 receives a digital signal from the A / D converter 4 based on a control signal from the control means 6, the DSP 5 functions as a data recording means and records the data (audio data) of the digital signal as a recording medium. 17 functions to record.
That is, the data recording device 1 is provided with data recording means for recording the sound sensed by the microphone 2 as sound data.

The DSP 5 functions as a data reproduction unit based on the control signal from the control unit 6 and reproduces the digital signal of the audio data recorded on the recording medium 17 in the same manner as the above data recording unit. It functions to send to the A converter 8.
In other words, the data recording apparatus 1 is provided with data reproducing means for reproducing the audio data recorded on the recording medium 17.

  A bus 13 for sending digital data signals between the A / D converter 4 and the D / A converter 8 and the DSP 5, and a bus 16 for sending digital data signals between the DSP 5 and the control means 6. However, a bus 15 for sending a digital data signal is interposed between the DSP 5 and the memory means 7, and a bus 14 for sending a digital data signal is interposed between the DSP 5 and the recording medium 17.

  When the recording medium 17 is attached to the data reproducing apparatus 1 in a predetermined state and connected to the DSP 5, the memory means 7 is a cluster (or a combined cluster) used for recording data from the recording medium 17, (Similarly) addresses can be read and stored, and the order of the addresses can be rearranged in the order opposite to the order in which the data was recorded on the recording medium 17.

  That is, as a specific action, the memory means 7 is a case where the data reproducing apparatus 1 performs normal reproduction for a specific file on the recording medium 17 and is reproducing the nth cluster SCn in the reproduction order. If a fast reverse operation is performed by the operation means 11, the (n-1) th cluster SCn-1 is searched for in the reproduction order.

Here, the cluster SCn-1 is not found immediately, but the memory means 7 first reaches the first cluster SC1 whose address is known for the above-mentioned specific file. Subsequently, the cluster SC2 is known from the cluster SC1 and the cluster number is checked, and the number is stored in the storage unit (not shown) of the memory means 7.
Subsequently, after reaching the cluster SC 2, the cluster number CN 3 is checked after reaching the cluster SC 3 known from the cluster SC 2, and the number is stored in the storage unit of the memory means 7.

By repeating the same, the order up to the nth cluster SCn and the known continuity from cluster SC1 to SCn is stored in the storage unit of the memory means 7.
Alternatively, when the continuous order of addresses from the recording medium 17 to the cluster SC1 to the cluster SCn can be known, the storage unit of the memory means 7 stores the order.
With the above-described continuous tracking of the cluster or storage of the memory in which the addresses from the cluster SC1 to the cluster SCn are tracked, the cluster numbers from the cluster SC1 to the cluster SCn are stored in the storage unit of the memory means 7 in order. Will be.

Therefore, the memory means 7 can obtain the order of backward playback by following the cluster numbers stored in the storage unit in the reverse order in the reverse direction.
That is, the DSP 5 reads and reproduces the cluster SCn-1 having the cluster number CNn-1. Next, based on the cluster number CNn-2 from the storage unit, the cluster CNn-2 is read and reproduced. When data reproduction is performed by continuously making the reverse chain of clusters correspond to each other, backward reproduction in the direction opposite to the data recording is obtained from the cluster CSn toward the cluster CS1.

If desired, the user can terminate the function by stopping the backward reproduction function by controlling the control means 6 via the operation means 11.
When the memory means 7 is not functioned, reproduction in the same direction as that recorded on the recording medium 17, that is, reproduction in the forward direction can be obtained.
In addition, the memory unit 7 has a configuration independent of the DSP 5 and the control unit 6, but may have a configuration in which the DSP 5 or the control unit 6 has the function and is integrated.
Depending on such a configuration, the convenience of modularization of component parts may be obtained.

The D / A converter 8 converts a digital signal which is data from the recording medium 17 input via the buffer 7 and the DSP 5 into an analog signal.
The amplifier 9 is connected to the subsequent stage of the D / A converter 8 and receives the analog signal of the audio data from the D / A converter 8, and processes the volume to a desired size.
The speaker 10 is connected to the subsequent stage of the amplifier 9 and receives an analog signal processed to a desired size, converts it into sound, and outputs it.

Here, the DSP 5, the memory means 7, the D / A converter 8, the amplifier 9 and the speaker constitute means for reproducing data that can be played back in the reverse direction in which the data is recorded in the opposite direction to the recorded direction. Has been.
The operating means 11 is disposed on the outer side surface (not shown) of the device main body casing (not shown) and operates the device function.

The display means 12 displays the functional state of the device at that time.
Specifically, the recording medium 17 is a semiconductor memory, and records audio data obtained by converting audio picked up by the microphone 2 into a digital signal.

The data reproducing apparatus 1 is configured as described above. Hereinafter, the function of the data reproducing apparatus 1 will be described with reference to the flowchart shown in FIG.
First, the user stores the recording medium 17 by connecting it to a connector (not shown) which is a connection end of the data reproducing apparatus 1 as prescribed within the apparatus main body casing.
Subsequently, the user operates the operation means 11 to turn on the main power supply, and starts the function of the data reproducing apparatus 1 to start data recording (REC mode).

When power is supplied to the data reproducing apparatus 1, the microphone 2 converts the input voice into an analog voice signal (voice data signal) and sends it to the amplifier 3. The amplifier 3 receives the analog signal from the microphone 2. Are processed into a desired size and sent to the A / D converter 4.
The A / D converter 4 receives the analog signal processed into a desired size from the amplifier 3, converts it into a digital signal, and sends it to the DSP 5 via the bus 13.

The DSP 5 functions as a data recording unit in response to a control signal corresponding to the REC mode from the control unit 6 and functions to record a digital signal input via the bus 13 on the recording medium 17.
Here, in the recording medium 17, the data of the digital signal from the DSP 5 is the first cluster SC1, the second cluster SC2, the third cluster SC3,..., The (n−1) th cluster SCn−1. , Are continuously recorded in the nth cluster SCn. Moreover, one file is constituted by this recording.

The order in which data recording from the first cluster SC1 to the nth cluster SCn is performed is recorded on the recording medium 17.
Here, the order of recording on the recording medium 17 is which cluster is the next cluster among consecutive clusters used for data recording? , Is the order that can be known in the forward direction.

Specifically, three consecutive clusters (m−1) to (m + 1) th used for data recording in the forward direction are arranged in this way. If the cluster SCm−1 is known, the next cluster is SCm, and if SCm is known, it is continuously known that the next cluster is SCm + 1.
On the contrary, the cluster SCm is known from the cluster SCm + 1 in the reverse direction, that is, the backward direction with respect to the forward direction, and the cluster SCm is not known from the cluster SCm-1.

Here, as described above, the cluster includes a cluster obtained by combining two or more clusters when the size of data to be recorded is large.
Also, the clusters used for data recording are not assigned consecutive numbers for reasons such as being physically adjacent to the recording medium 17, but the clusters of the recording medium 17 are in a random arrangement. When used as a data record in the file structure, it means a number assigned according to the order of the data record.

When the recording, that is, the data recording reaches a desired end time, the user operates the operation means 11 to stop the data recording.
After that, when the recorded data is to be reproduced in the direction opposite to the recorded direction, that is, when it is desired to perform the backward reproduction, the operation means 11 is operated to specify the file related to the recorded data. Perform backward playback operations.

Here, a request signal for reading the file relating to the above-described data and reproducing the file in a direction opposite to the data recording direction is sent from the operation means 11 to the control means 6.
The control means 6 controls the memory means 7 to read successive addresses related to data recording from the corresponding file on the recording medium 17.

The memory means 7 reads the address of the cluster used for data recording from the recording medium 17 and stores it.
Subsequently, the memory means 7 searches for a cluster SC1 whose address is known. Here, as described above, since the clusters continuously used in the data recording can know the forward order of the data recording, the memory means 7 starts from the first cluster SC1 used in the data recording. The order of addresses up to the nth used cluster SCn is stored in the storage unit.

Here, the memory means 7 obtains the order of the forward addresses in which the data of the clusters used for recording the data relating to the file are recorded.
Further, the memory means 7 obtains the reverse order based on the forward address order of the used clusters obtained here.

The DSP 5 reproduces the corresponding file read from the recording medium 17 by tracing back from the nth cluster SCn to the first SC1 according to the reverse address order obtained by the memory means 7.
The digital signal (data) obtained by this reproduction is sent to the D / A converter 8 via the bus 13.

The D / A converter 8 converts the digital signal from the bus 13 into an analog signal and then sends it to the amplifier 9.
The amplifier 9 amplifies the analog signal from the D / A converter 8 to a desired volume and sends it to the speaker 10.
The speaker 10 converts the analog signal from the amplifier 9 into sound and outputs the sound.

  Here, the user can listen to the sound reproduced from the speaker 10 in the direction opposite to the direction of recording the data (audio data) of the corresponding file recorded in the recording medium 17.

  As described above, when the data reproducing apparatus 1 reproduces the data recorded on the recording medium 17 in the direction opposite to the direction in which the data was recorded, the data reproducing apparatus 1 first reproduces the cluster SCn and then the cluster SCn−1. Find and play, then find and play cluster SCn-2, and instead of continuously, the memory means 7 first obtains a cluster SC1 whose address is known, then The address of each cluster from cluster SC1 to cluster SCn, which is the order in which the data was recorded, is sequentially tracked to determine and store the order of the addresses. Since the cluster is played back in the reverse order, it is possible to easily find the cluster without requiring a long time to find the cluster.

  In addition, the data reproducing apparatus 1 has a configuration in which only the memory means 7 having the above-described functions is added as compared with the conventional data reproducing apparatus, and an arbitrary file is reproduced in the direction in which the data is recorded. For the reproduction in the direction, normal reproduction may be performed, or the address of the first cluster corresponding to the data may be easily found by the memory means 7 and then the subsequent clusters may be reproduced.

Further, the data reproducing apparatus disclosed in Japanese Patent Laid-Open No. 2001-338484 requires the use of a recording medium having two storage units for storing the addresses of the clusters. Even if the recording medium has only one storage section for storing the address, no problem occurs.
That is, the data reproducing apparatus 1 is ensured for versatility.

In the data reproducing apparatus 1, the data to be recorded is audio, but it may be video, or may be a combination of audio and video.
Although the data reproducing apparatus 1 is configured to include means for recording data, it may have only a function for reproducing data.

  In the data reproducing apparatus 1, since the recording medium 17 is a semiconductor memory, the data recording means and the data reproducing means are constituted by the DSP 5, but it is preferable to select appropriately according to the type of the recording medium.

In the best embodiment of this invention, it is a block diagram explaining the structure at the time of connecting the recording medium. It is a flowchart explaining the principal part function of the form shown in FIG. FIG. 3 is a view corresponding to FIG. 2 in a conventional example.

Explanation of symbols

1: Data reproduction device 2: Microphones 3 and 9: Amplifier 4: A / D converter 5: Digital signal processor (DSP, data recording means and data reproduction means)
6: Control means 7: Memory means 8: D / A converter 10: Speaker 11: Operation means 12: Display means 17: Recording medium

Claims (2)

When the data recording area is divided into a plurality of clusters and the data to be recorded is larger than the size of the cluster, the file is stored in a combined cluster obtained by associating and combining two or more clusters. Recording medium configured to record data in units of files on a recording medium configured to record data in units, and also to record the order of cluster addresses used for recording the data when recording data A data reproducing means for reproducing the recorded data;
From the recording medium configured as described above, the addresses of the clusters used for data recording and / or the cluster of the combination are read and stored in the data recording order, and the data recording order of the addresses is rearranged in the reverse order. Memory means to obtain;
When reproducing the data recorded on the recording medium having the above configuration from the end toward the head, the address in the reverse order of the order in which the data was recorded on the recording medium based on the storage contents of the memory means. A data reproducing apparatus comprising control means capable of controlling the reproducing means to reproduce data recorded on the recording medium. 2. The data reproducing apparatus according to claim 1, wherein the data reproducing means is a digital signal processor, and the digital signal processor and the memory means can be integrated.

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