JP2598534B2 - Image and audio data recording device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a video and audio data compression recording device,
In particular, the present invention relates to an apparatus for recording compressed image or audio signal data on a recording medium divided into a plurality of recording areas in advance.

2. Description of the Related Art When recording image signal or audio signal data in a memory such as a semiconductor, compression encoding is performed to reduce the recording capacity.

When recording image or audio signal data in the semiconductor memory as described above, the memory is divided into a plurality of areas (clusters) having the same recording capacity in advance, and one or a plurality of clusters are used according to the amount of data. It is proposed by the present applicant to record data.
No. 10997.

According to such a recording method, the memory is divided into a plurality of clusters, and the first cluster is used for storing management data, and the other clusters are used for recording image data. A directory and a MAT (memory allocation table) are provided in the management data area. For example, when compressed image data is recorded in a plurality of clusters, a cluster in which the head of the image data is recorded is stored in the directory of the management data area. A cluster number is recorded in the MAT, and a cluster number following a cluster number in which the first one of the image data is recorded. Writing and reading of the image data are managed by these management data.

For example, when new image data is recorded in the memory, the number of clusters corresponding to the image data to be recorded is determined, and the unrecorded clusters are confirmed to have a larger capacity before recording. I do.

By the way, even if some abnormality occurs in the compression processing or the fixed length processing of the image data and the image data is output from the compression encoding unit beyond the original data length, these data are also sent to the memory. Therefore, in such a case, data exceeding the preset number of clusters is sent, and if these data are recorded in the memory exceeding the preset number of clusters, the necessary data may be destroyed. was there. In addition, in the case of recording audio data, the length of the audio data is not always constant unlike the image data, so that it is required to cut off the data amount at a fixed length.

Objective The present invention solves the drawbacks of the prior art, and even when the data length exceeds a predetermined amount due to an abnormality in the compression processing, fixed length processing, or the like, the data in other areas is thereby reduced. It is an object of the present invention to provide an image and audio data recording device in which the amount of data to be recorded is cut off at a predetermined amount so as not to be affected.

DISCLOSURE OF THE INVENTION According to the present invention, an apparatus for recording at least one of image data and audio data on a recording medium,
The recording medium is divided into a plurality of unit recording areas for each predetermined recording capacity in advance, and an image and audio data recording apparatus that records image and audio data in a plurality of unit recording areas of the recording medium includes an image and an audio data to be recorded. Data amount counting means for counting audio data, address storage means for recording instructions of a plurality of unit recording areas of a recording medium for recording recorded image and audio data, recorded image and audio data, and address storage Switching means for switching and outputting the address instruction data output from the means; outputting instructions for a plurality of unit recording areas of a recording medium for recording image and audio data to the address storage means; Control means for outputting, and a finger of a unit recording area inputted from the control means to the address storage means. And comparing means for comparing the number of unit recording areas output from the address storage means with the number of unit recording area instructions output from the address storage means. When it is detected that the number of instructions of the unit recording area to be output is equal, the output of image and audio data is limited in accordance with the data amount counted by the data amount counting means.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to an image and audio data compression recording apparatus will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an embodiment in which the present invention is applied to an image data compression recording apparatus.

This apparatus has an orthogonal transform unit 26 and an encoding unit 28 for compressing and encoding image data. In the present embodiment, image data will be described, but the present invention can be similarly applied to audio data. Image data captured by, for example, an electronic still camera is input to the orthogonal transform unit 26. The orthogonal transformation unit 26 performs orthogonal transformation such as two-dimensional cosine transformation on the input image data. The output from the orthogonal transform unit 26 is input to the encoding unit 28. The encoding unit 28 encodes the orthogonally transformed image data by Huffman encoding or the like. The output from the encoding unit 28 is sent to the selector 34 and the code amount counter 32.

To the other input terminal of the selector 34, an address of a cluster described later is input from the address generator 18. Selector 34
Switches between the encoded image data input from the encoding unit 28 and the cluster address input from the address generator 18.

The code amount counter 32 counts the amount of image data output from the encoding unit 28, and outputs a cluster switching request signal when the amount of image data reaches the amount of data recorded in a cluster. The cluster switching request signal from the code amount counter 32 is sent to the address generator 18 and the flip-flop circuit.
Sent to 22 and selector 34.

The MATRAM (memory allocation table RAM) 16 stores the number of each cluster necessary for recording image data in a plurality of clusters of the memory card 44. When recording an image, the control unit 40 checks in advance which clusters are empty, and sets the order in which image data is recorded in these clusters.
The MATRAM 16 stores the numbers of these clusters specified by the control unit 40. The output from the MATRAM 16 is sent to an address generator 18. The address generator 18 sets the cluster number output from the MATRAM 16 to the upper 11 bits, and
Outputs 24-bit address data with all bits set to 0. The start address of the cluster is specified by 24-bit address data in which all the lower 13 bits are 0. The 24-bit address data becomes a real address indicating the cluster when an image is recorded on the memory card 44.

The device is further provided with two address counters 10,12. The address counter 10 counts the number of clusters instructed by the control unit 40 to the MATRAM 16 before recording image data. On the other hand, the address counter 12 reads the address read from the address generator 18 when the image data is recorded on the memory card 44, that is,
Count the number of clusters. Outputs from the address counters 10 and 12 are input to the selector 14. Selector 14
Selects the output of the address counter 10 or 12 and sets the MATRAM
Output to 16. The selector 14 sends the output from the address counter 10 to the MATRAM 16 at the time of pre-processing of image recording, and outputs the output from the address counter 12 to the MATRAM 16 at the time of image recording.
Send to TRAM16.

The outputs from address counters 10 and 12 are also sent to data comparator 20. The data comparator 20 compares the count values of the address counters 10 and 12, and outputs a match signal when they match. This coincidence signal is output when recording on a predetermined number of clusters is completed. The output from the data comparator 20 is input to the D terminal of the flip-flop circuit 22. On the other hand, a cluster switching request signal from the code amount counter 32 is input to a CK (clock) terminal of the flip-flop circuit 22. The flip-flop circuit 22 outputs a cluster-over signal when a cluster switching request signal is input from the code amount counter 32 and a coincidence signal is output from the data comparator 20.
That is, the end of recording to a preset number of clusters is confirmed by the coincidence signal, and when the address of the next cluster is made available for output by the cluster switching request signal, a cluster over signal is output.

The cluster-over signal from the flip-flop circuit 22 is input to one input of the AND circuit 30. AND circuit
A cluster switching request signal from the code amount counter 32 is input to the other input of 30. The AND circuit 30 outputs a C-BUSY signal when the cluster over signal from the flip-flop circuit 22 and the cluster switching request signal from the code amount counter 32 are input. That is, it is detected that a predetermined number of clusters has been reached by the cluster over signal, and when a cluster switching request signal exceeds a cluster to be recorded and a recording start state for the next cluster is started, a C-BUSY signal is output, The output from the encoding unit 28 is stopped. The C-BUSY signal normally falls to a low level when image data recording is completed, and returns (is output) to a high level by performing an AND operation as described above.

The cluster over signal from the flip-flop circuit 22 is also sent to the three-state buffer 38. The 3-state buffer 38 stores addresses recorded on the memory card 44,
It is a buffer that can store image data and can stop outputting these data. The three-state buffer 38 is connected to the flip-flop circuit 22.
The output of data to the memory card 44 is stopped by the cluster-over signal from.

A memory card 44 is detachably connected to the three-state buffer 38 via a connector 42. Memory card 44
Has a semiconductor memory, which is divided into a predetermined number of clusters as described above.

Here, a data recording method in the memory card 44 will be briefly described.

As shown in FIG. 3, the recording area of the memory card 44 is divided into a predetermined number of uniform clusters 114 in advance, and a plurality of clusters 114 are selected from these clusters 114, for example, as shown in FIG. One image data (packet 1
Record 22). A plurality of clusters 114 constituting the packet 112 may be set continuously, or may be set discretely as in the example shown in FIG. When recording new image data, a predetermined number of clusters are selected from the clusters 114 other than the already recorded clusters, and a packet 122 is formed.

In the method of selecting and recording a predetermined number of clusters 114 according to the amount of image data as described above, the number of the used cluster is recorded for each packet 122 of each recorded image data. Is necessary for searching and reading out image data. Therefore, a portion corresponding to the first cluster 114 of the memory is set as a management area, and a header, a packet information area, a directory, and a MAT area are provided as shown in FIG. As shown in the figure, the directory records the start cluster of each packet (each image data). That is, the number of the first cluster in which each packet is recorded is recorded. Also, MA
In T (memory allocation table), for each cluster, the number of the cluster recorded following that cluster is recorded. The reading of the image is facilitated by these data. That is, when image data is read, the number of the first cluster in which the image data (packet) is recorded is read from the directory, and the number of the subsequent cluster is read from the MAT, so that a group of image data is read. Can be read.

This apparatus is used to record encoded image data on the memory card 44 using such a recording method.
This prevents the recording of such extra data when the image data is output beyond a predetermined number of clusters due to an abnormality such as 28.

The control unit 40 is a control unit that controls each unit of the present apparatus.In particular, when image data is recorded in a plurality of clusters of the memory card 44, an empty cluster is searched for and a cluster to be recorded is selected from the empty clusters. And instruct the MATRAM 16 of the numbers of these clusters.

The operation of the present apparatus will be described with reference to the timing chart of FIG.

When storing the image data, the control unit 40 determines the number of clusters to be used from the amount of the compressed image data to be recorded.
Next, the image data already recorded on the memory card 44 is read via the connector 42 and the 3-state buffer 38,
It is determined which cluster of the memory card 44 is free. The control unit 40 determines whether or not the compressed image data to be recorded can be recorded in an empty cluster, and if recording is possible, decides in which cluster to record. The control unit 40 sends the determined cluster number to the address counter 10 and switches the selector 14 to the address counter 10 side.

The address counter 10 counts the cluster number sent from the control unit 40, and the output from the address counter 10 is input to the MATRAM 16 via the selector 14. The MATRAM 16 sequentially stores the input cluster number, that is, the cluster number used for recording. When the output of the cluster number from the control unit 40 is completed, the address counter 10 stops counting, and the cluster number remains set. In this embodiment, as shown in FIG.
Since the image data is recorded using the clusters, the count value of the address counter 10 stops at N.

When the output of the cluster number is completed, the control unit 40
A control signal is sent to AM16, and the output of the cluster number input to MATRAM16 from MATRAM16 is started. MATRAM
Reference numeral 16 sequentially outputs 11-bit addresses indicating the numbers of clusters used for recording. The 11-bit address output from the MATRAM 16 is input to an address generator 18, and the address generator 18 sets the 11 bits as an upper address,
The lower 13 bits are each added with 0, and sent to the selector 34 as a real address indicating the head of each cluster.

A control signal is sent from the code amount counter 32 to the selector 34, and the selector 34 is switched to the address generator 18 side,
When the cluster switching signal from the code amount counter 32 is sent to the address generator 18, the address of the first cluster is sent from the address generator 18 to the selector 34. This address is stored in the selector 34, selector 36, 3-state buffer 3
8. The address is sent to the memory card 44 through the connector 42 and the address indicating the cluster of the memory card 44 to be recorded is specified. This address is also sent to the address counter 12.

Next, the selector 34 is switched to the encoding unit 28 side by the control signal from the code amount counter 32, and the compression-encoded image data output from the encoding unit 28 is passed through the selector 34 according to the address of the memory card 44. It is recorded in the designated cluster sequentially.

Such a switching operation of the selector 34 is repeated,
As shown in FIG. 2, the head address of each cluster and the compressed image data recorded in that cluster are sent to the memory card 44 for each cluster. As shown in the figure, the lower, middle and upper 8 bit addresses of the cluster are sent to the memory card 44 for each R / W signal output from the control unit 40, as shown in FIG. The operation of transmitting the address to the memory card 44 and recording the compressed image data is repeated. The address of each cluster output from the address generator 18 is also sent to the address counter 12, and the address counter 12 counts the number of the cluster.

This operation is repeated, and the normal recording operation is completed by recording image data in a predetermined number, that is, N clusters as shown in FIG. Each time the head address of the N clusters is output from the address generator 18,
This address is also sent to the address counter 12 as described above, and the address counter 12 counts this. Therefore, when the addresses of the N clusters are output, that is, when the cluster switching signal in FIG. 2 goes high (address generator side), the value of the address counter 12 is set to N. The values of the address counters 10 and 12 are sent to the data comparator 20 and compared. Address counter
Since the value of 10 is set to N as described above, when the output from the address counter 12 becomes N, the values of both address counters 10 and 12 match, and the A = B signal in FIG. Low level.

A match signal (A = B) is output from the data comparator 20 to the flip-flop circuit 22. When the cluster switching signal corresponding to the (N + 1) th cluster is output from the code amount counter 32, the flip-flop circuit 22 outputs the cluster over signal (low level) shown in FIG. When the cluster-over signal is output (becomes low level), it is sent to the 3-state buffer 38, and the transmission of data from the 3-state buffer 38 to the memory card 44 is stopped. The cluster over signal is also sent to the address counter 12 to reset the count of the address counter 12.

The cluster over signal is also sent to the AND circuit 30. The AND circuit 30 outputs a C-BUSY signal by ANDing the cluster over signal and the cluster switching signal from the code amount counter 32. Therefore, N
When the address of the cluster is sent, that is, when the cluster switching signal goes high, the cluster-over signal is high. Output when the image data output of the cluster starts. Therefore, the image data of the N-th cluster is output from the encoding unit 28. When the output of the image data of the N-th cluster is completed, the C-BUSY signal returns to the low level, and the output of the image data from the encoding unit 28 is stopped. After the data of the Nth cluster is transmitted, the cluster-over signal becomes low level. Therefore, even if the cluster switching signal becomes high level, the C-BUSY signal is not output and remains at low level. Therefore, the output from the encoding unit 28 is stopped.
This can prevent erroneous output of image data corresponding to the (N + 1) th cluster.

Therefore, even when an abnormality occurs in the encoding unit 28 or the like and normal operation is not performed, it is possible to prevent the encoding unit 28 from outputting data exceeding a predetermined number N.

As described above, according to the present apparatus, even when an abnormality occurs in the encoding unit 28 or the like, it is possible to prevent abnormal data from being recorded on the memory card 44 exceeding a predetermined number of clusters. Therefore, since recording can be suppressed in a preset cluster, it is possible to prevent the necessary data already recorded from being destroyed. In addition, it is possible to prevent output of unnecessary encoded data from the encoding unit 28.

Although the above embodiment has been described with respect to a compression recording apparatus for image data, the present invention is not limited to image data, but can be similarly applied to a compression recording apparatus for audio data. When applied to an audio data compression recording device, recording of audio data can be terminated at a predetermined length. Therefore, even when compressed audio data having a variable length is recorded, it can be recorded within a predetermined number of clusters.

Although the above embodiment describes a compression recording device, the present invention is not limited to the compression recording device, but can be applied to a storage device for uncompressed data.

Effects According to the present invention, even when an abnormality occurs in the amount of data to be recorded, it is possible to prevent abnormal data from being recorded on a memory card exceeding a predetermined number of clusters.
Therefore, since the recording can be suppressed in the cluster set in advance, it is possible to prevent the necessary data already recorded from being destroyed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment in which the present invention is applied to an image data compression recording apparatus, FIG. 2 is a timing chart showing the operation of the apparatus shown in FIG. 1, and FIG. 3 is a memory by the apparatus shown in FIG. FIG. 4 is a conceptual diagram showing the concept of a card storage management system. FIG. 4 is an explanatory diagram of a memory card storage management system by the apparatus shown in FIG. Explanation of Signs of Main Parts 10, 12… Address Counter 14… Selector 16… MATRAM 18… Address Generator 20… Data Comparator 22… Flip-Flop Circuit 30… AND Circuit 32… Code Counter 34 ... Selector 44 ... Memory card

Claims (2)

(57) [Claims] An apparatus for recording at least one of image data and audio data on a recording medium, wherein the recording medium is divided into a plurality of unit recording areas for each predetermined recording capacity in advance, and In an image and sound data recording device for recording sound data in a plurality of unit recording areas of the recording medium, the device counts the data amounts of the image and sound data recorded on the recording medium, and Data amount counting means for outputting a switching request for switching the unit recording area when the amount reaches the predetermined storage capacity; and indication of the plurality of unit recording areas of the recording medium for recording the recorded image and audio data. From the address storage unit, and from the address storage unit, Switching means for switching and outputting input address instruction data; outputting instructions of the plurality of unit recording areas of the recording medium for recording the image and audio data to the address storage means; A control unit for outputting the instruction from the control unit; and comparing the number of instructions of the unit recording area input to the address storage unit from the control unit with the number of instructions of the unit recording area output from the address storage unit. And a limiting means for limiting the output of the image and audio data. The limiting means outputs the number of instructions of the unit recording area input to the address storage means and the output from the address storage means. When the comparing means detects that the number of instructions in the unit recording area is equal to the number of instructions, the data amount counting means outputs the same. In response to said change request, the image and audio data recording apparatus characterized by limiting the output of the image and audio data. 2. The apparatus according to claim 1, wherein said comparing means comprises two counters and a comparator,
One of the two counters counts the number of unit recording area instructions input from the control means to the address storage means, and the other counts the number of unit recording area instructions output from the address storage means. Wherein the comparator compares the count values of the two counters.