JP2001110125A - Recording/reproducing device and recording/reproducing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a recording/reproducing device and the method capable of converting the compression system while realizing the transfer of material at the speed beyond 1-fold speed without bringing the increase of product cost. SOLUTION: The transfer of material at the speed beyond 1-fold speed is realized without bringing the increase of product cost due to the enlargement of the hardware scale, since the compression material by the 1st compression system inputted at a transfer rate of multiplied speed is recorded as it is so that the recorded compression material is reproduced at the transfer rate of the inputted time and transferred to the outside. Also, since the compression material by the 1st compression system recorded on a RAID part 30 is converted into the 2nd compression system capable of decoding at the own inside with a transcoder 4 while reproducing at unmultiplied speed by utilizing the access idle time to the RAID part 30, the constitution of the large scaled hardware such as converting the compression system in real time while transferring at the multiplied speed like the conventional practice is unrequired, thereby the increase of product cost is avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording / reproducing apparatus and a recording / reproducing method for recording / reproducing by converting a compression method of an input compressed material into a different compression method.

[0002]

2. Description of the Related Art As a non-linearly accessible recording medium, for example, a RAID (Redundant Arrays of Inexpensive Disks) in which a plurality of hard disk drives are arranged.
2. Description of the Related Art A video server that records and reproduces a material (video / audio data) using a video server is known. This type of apparatus has a normal recording / reproducing function in which a material input in the SDI format is compressed in real time and recorded in RAID, or a material compressed and recorded in RAID is decompressed in real time and reproduced and output in SDI format. In addition, those having a material transfer function of converting a compression method of a compressed material transmitted at high speed according to a transmission standard such as SDTI and recording and reproducing the material have been developed.

[0003] The material transfer function is a GOP (Group Of Pic).
) Since compression methods (eg, MPEG) of various specifications having different lengths, bit rates, etc. are mixed, when a compressed material of a different compression method is exchanged, a compression material of a first compression method supplied from the outside is used. Is converted to a second compression method that can be decoded internally and recorded, or is reproduced and converted back to the first compression method for external transfer.

FIG. 3 is a block diagram showing a schematic configuration of a recording / reproducing apparatus having such a material transfer function. The recording / reproducing apparatus shown in the figure includes a material transfer processing unit 10 for realizing the above-described material transfer function, a recording / reproduction processing unit 20 for realizing a normal recording / reproduction function, and a RAID unit 30 functioning as a non-linear recording / reproduction means. Consists of

[0005] The material transfer processing section 10 includes a control section 1 for controlling the operation of each section, an SDTI receiving section 2, a selector 3, a transcoder 4, a recording buffer 5, a reproduction buffer 6, and an SD card.
It comprises a TI transmission unit 7. The control unit 1 includes a CPU and the like, and gives a recording / reproducing instruction to the RAID unit 30 and controls the operation of each unit of the material transfer processing unit 10. Specifically, for example, the transmission / reception timing is instructed to the SDTI reception unit 2 and the SDTI transmission unit 7, and the write / read instruction and the write / read address are supplied to the recording buffer 5 and the reproduction buffer 6. The transcoder 4 is also provided with a material transfer speed and a reference frame timing required for the conversion process. Further, the selector 3 is supplied with a select signal SEL for switching the transfer direction.

[0006] The SDTI receiving section 2 extracts and outputs valid data (material stream) from compressed data transmitted in accordance with the SDTI standard. The selector 3 selects the input terminal A during reception and selects the input terminal B during transmission according to the select signal SEL supplied from the control unit 1.

[0007] The transcoder 4 converts a compressed material according to the first compression method into a second compression method, or converts a compressed material according to the second compression method back into the first compression method. When the first compression method is converted to the second compression method, the GOP (Group Of Picture) length and bit rate are temporarily converted to the second compression method after decoding the compressed material by the first compression method. Encoding is performed for conversion, thereby generating and outputting a material stream having a compression parameter different from that of the input compressed material. Similarly, when the second compression method is converted back to the first compression method, the GOP length and the bit rate are first decoded and the GOP length and the bit rate are first decoded. Encode to convert to system. In the transcoder 4, in order to prevent image quality deterioration due to such repetition of decoding / encoding, for example, at the time of re-encoding processing,
The previous encoding parameter is referred to as history information.

In the case where the transcoder 4 converts the compression method at N times speed, as shown in FIG. 4, the transcoder 4a-1 having a 1 times speed compression method conversion capability.
To 4a-N are arranged in N stages in parallel, and a pre-buffer 4b and a post-buffer 4c are provided on the input side and the output side of the transcoders 4a-1 to 4a-N arranged in parallel, respectively. The stream of the compressed material to be temporarily stored is temporarily stored in the pre-buffer 4b, then distributed to the transcoders 4a-1 to 4a-N, and subjected to the compression system conversion.
c temporarily stored in the transcoders 4a-1 to 4a-
By returning the N converted outputs to one stream of compressed material, the compressed material whose compression method has been converted in real time is transferred at N times speed.

The recording buffer 5 temporarily stores a compressed material output from the transcoder 4 in accordance with a write instruction from the control unit 1, and reads out the compressed material in response to a read instruction from the control unit 1 to read out the compressed material and store the compressed material in the RAID unit. Output to 30. As a result, a compressed material obtained by converting the compression method is recorded in the RAID unit 30. The playback buffer 6 has the RAI
The compressed material reproduced from the D unit 30 is temporarily stored in accordance with a write instruction from the control unit 1, while the compressed material is read in accordance with a read instruction from the control unit 1 and read out by the selector 3.
Is supplied to the input terminal B. The SDTI transmitting unit 7 formats the compressed material output from the transcoder 4 into SDTI standard compressed data and transmits the data.

In the above configuration, when receiving a reception instruction from the control unit 1, a compressed material (first compression method) extracted from the SDTI standard compressed data is input to the transcoder 4 via the selector 3, and After being converted in real time by the coder 4 at N times speed to the second compression method, it is recorded in the RAID unit 30 via the recording buffer 5. When the control unit 1 instructs to transfer the recorded compressed material to an external device, the compressed material stream recorded in the RAID unit 30 according to the second compression method is reproduced, and is transmitted through the reproduction buffer 6 and the selector 3. Then, it is supplied to the transcoder 4 again, converted again into the first compression method, and transmitted from the SDTI transmission unit 7 as compressed data of the SDTI standard.

[0011]

In a conventional recording / reproducing apparatus having such a material transfer function, the hardware scale of the transcoder 4 for converting the compression method in real time is relatively large, and the transfer rate cannot be increased. In order to be able to handle up to double speed, a transcoder 4 having a 1 × speed compression method conversion capability is required for the transfer double speed. Therefore, there is a problem that an attempt to realize a high-speed material transfer leads to an increase in product cost due to an increase in hardware scale. Therefore, the present invention has been made in view of such circumstances, and a recording / reproducing apparatus and a recording / reproducing apparatus capable of converting a compression method while realizing material transfer exceeding 1 × speed without incurring high product cost. It is intended to provide a way.

[0012]

In order to achieve the above object, according to the first aspect of the present invention, after a compressed material input at a transfer rate exceeding at least 1 times speed is recorded on a recording medium, the compressed material is recorded on the recording medium. Transfer means for reproducing the recorded compressed material at the transfer rate at the time of input and externally transferring the compressed material recorded on the recording medium by the transfer means,
And a compression method conversion means for converting the compression method of the reproduced compressed material into a different compression method and re-recording it on the recording medium.

According to the second aspect of the present invention, at least one
A first transfer means for recording a compressed material input at a transfer rate exceeding double speed on a recording medium, reproducing the compressed material recorded on the recording medium at a transfer rate at the time of input, and externally transferring the compressed material; Using the free access time to the medium, the compressed material recorded on the recording medium by the first transfer means is reproduced, the compression method of the reproduced compressed material is converted into a different compression method, and the compressed material is re-transferred to the recording medium. It is characterized by comprising a compression method conversion means for recording, and a second transfer means for reproducing a compressed material of a different compression method re-recorded on a recording medium by the compression method conversion means and externally transferring the same.

According to the third aspect of the present invention, at least one
After recording a compressed material input at a transfer rate exceeding double speed on a recording medium, the compressed material recorded on the recording medium is reproduced at the transfer rate at the time of input and externally transferred; Reproducing the compressed material recorded on the medium, converting the compressed method of the reproduced compressed material into a different compression method, and re-recording the compressed material on the recording medium.

According to the fourth aspect of the present invention, at least one
A first transfer step of recording a compressed material input at a transfer rate exceeding double speed on a recording medium, reproducing the compressed material recorded on the recording medium at a transfer rate at the time of input, and externally transferring the compressed material; The compressed material recorded in the recording medium in the first transfer process is reproduced by using the free access time to the medium, the compression method of the reproduced compressed material is converted into a different compression method, and the compressed material is transferred to the recording medium. It is characterized by comprising a compression method conversion step of re-recording, and a second transfer step of reproducing and externally transferring a compressed material of a different compression method re-recorded on a recording medium by the compression method conversion step. .

According to the present invention, after a compressed material input at a transfer rate exceeding at least 1 × speed is recorded on a recording medium, the compressed material recorded on the recording medium is reproduced at the input transfer rate and externally transferred. Therefore, it is possible to transfer the material at a speed higher than 1 × speed without increasing the product cost due to an increase in hardware scale. In addition, since the compressed material recorded on the recording medium is reproduced at the time of transferring the material, the compression method of the reproduced compressed material is converted into a different compression method and re-recorded on the recording medium. It is possible to convert the compression method without increasing the cost.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a recording / reproducing apparatus according to one embodiment. In this figure, the same components as those of the above-described conventional example are denoted by the same reference numerals, and description thereof will be omitted.

The recording / reproducing apparatus shown in FIG. 1 is different from the conventional example shown in FIG. 3 in that the output of the SDTI receiving section 2 or the compression at 1 × or less is performed in accordance with the select signal SEL1 supplied from the control section 1. A selector 8 is provided for selecting one of the outputs of the transcoder 4 for converting the system and supplying it to the recording buffer 5, and outputs the output of the reproduction buffer 6 in accordance with the select signal SEL <b> 2 supplied from the control unit 1. 4 or a selector 9 for inputting to either the SDTI receiving unit 2.

According to such a configuration, (a) when receiving a compressed material by the first compression method, the control unit 1 sends the select signal SEL1 for instructing the selector 8 to select the input terminal A side. appear. Then, the compressed material (first compression method) extracted by the SDTI receiving unit 2 is sequentially and temporarily stored in the recording buffer 5 via the selector 8 at the transfer double rate, and then the RAI is directly converted without converting the compression method.
Recorded in the D section 30.

(B) On the other hand, when transmitting the compressed material according to the first compression method recorded in the RAID unit 30, the control unit 1 sends a select signal SEL2 instructing the selector 9 to select the output terminal B side. Occurs. Then, the compressed material reproduced by the RAID unit 30 at the transfer double rate at the time of recording and using the first compression method is used as it is in the reproduction buffer 6.
Is transmitted from the SDTI transmission unit 7 as compressed data of the SDTI standard via the.

(C) In the operation of the above item (a), the RAID unit 3
When converting the compressed material according to the first compression method recorded in the first compression method into the second compression method, the control unit 1 instructs the selector 8 to select the input terminal B side.
In addition to generating L1, it generates a select signal SEL2 for instructing the selector 9 to select the output terminal A side. Then, under the instruction of the control unit 1, the compressed material by the first compression method, which is reproduced at 1 × speed from the RAID unit 30,
The data is input to the transcoder 4 via the reproduction buffer 6 and the selector 9, is converted to the second compression method at 1 × speed by the transcoder 4, and is re-recorded on the RAID unit 30 via the recording buffer 5. You. In this case, RAID
The unit 30 re-records the file as a separate file from the compressed material by the first compression method recorded by the operation (a).

Such re-recording is executed as foreground processing of the control unit 1 or the RAID unit 3
0 may be executed as a background process using the free time in the time division slot.
When the compression method is converted by the background processing, the conversion performed at 1 × speed in the transcoder 4 is intermittently processed, so that the effective processing rate is 1 × speed or less.

The compressed material converted from the first compression method to the second compression method and re-recorded in the RAID unit 30 passes through the reproduction buffer 6 as described in the above item (b). It is also possible to externally transfer as compressed data of the SDTI standard from the SDTI transmitting unit 7. As a result, it is possible to transfer a compressed material that lacks real-time performance but matches the compression method of the transfer destination, and maintain compatibility between devices using different compression methods.

As described above, in the recording / reproducing apparatus according to the present invention, the compressed material according to the first compression method input at the transfer double rate is recorded as it is, and the recorded compressed material is reproduced at the input transfer rate. Since the external transfer is used, material transfer exceeding 1x speed can be realized without increasing the product cost due to an increase in hardware scale. By this material transfer, the transcoder 4 can decode the compressed material recorded in the RAID unit 30 by the first compression method at 1 × speed using the idle time of access to the RAID unit 30 and internally by the transcoder 4. Since the data is converted to the second compression method, a large-scale hardware configuration for converting the compression method in real time while transferring data at double speed as in the related art is not required, thereby avoiding an increase in product cost.

In the above-described embodiment, the transcoder 4 for converting the compression method is realized by hardware. However, instead of this, a transcoding buffer is used as in the modification shown in FIG. 11 may be provided, and the processing of converting the compression method by the CPU of the control unit 1 may be realized by software using the buffer 11 as a work memory. In such an aspect, since there is no restriction on hardware, it is possible to convert a compression material by the first compression method input from the outside by selecting an arbitrary compression method from various compression methods. Therefore, high versatility can be realized at low cost.

[0026]

According to the recording / reproducing apparatus of the present invention, after the transfer means records the compressed material input at least at a transfer rate exceeding 1x speed on the recording medium, the compression material recorded on the recording medium is used. While the material is reproduced at the transfer rate at the time of input and externally transferred, the compression method conversion means reproduces the compressed material recorded on the recording medium by the transfer means and converts the compression method of the reproduced compressed material to a different compression method. Then, since the data is re-recorded on the recording medium, the compression method can be converted while realizing material transfer exceeding 1 × speed without incurring a high product cost due to an increase in hardware scale. According to the recording / reproducing apparatus of the second aspect, after the first transfer means records the compressed material inputted at least at a transfer rate exceeding 1 × speed on the recording medium, the first transfer means deletes the compressed material recorded on the recording medium. Since reproduction is performed at the transfer rate at the time of input and external transfer is performed, material transfer exceeding 1x speed can be realized without increasing the product cost due to an increase in hardware scale. Also, the compression method conversion means includes:
The compressed material recorded on the recording medium is reproduced by the first transfer means using the idle time when the recording / reproduction access to the recording medium is not performed, and the compression method of the reproduced compressed material is converted into a different compression method. Therefore, the compression method can be converted without causing an increase in product cost due to an increase in hardware scale. Furthermore, since the second transfer means reproduces the compressed material of a different compression method re-recorded on the recording medium by the compression method conversion means and externally transfers the material, it lacks real-time performance,
A compressed material that matches the compression method of the transfer destination can be transferred, and compatibility between devices having different compression methods can be maintained. According to the recording / reproducing method according to claim 3,
After recording the compressed material input at a transfer rate exceeding at least 1x speed on a recording medium by a transfer process, the compressed material recorded on the recording medium is reproduced at the transfer rate at the time of input and externally transferred. It is possible to realize material transfer exceeding 1x speed without incurring high product cost due to an increase in scale. In the compression method conversion process, the compressed material recorded on the recording medium in the transfer process is reproduced, and the compression method of the reproduced compressed material is converted into a different compression method and re-recorded on the recording medium. According to the recording / reproducing method according to claim 4, wherein the compression method can be converted without increasing the product cost due to the increase in scale, the input is performed at a transfer rate exceeding at least 1x speed in the first transfer step. After recording the compressed material on the recording medium, the compressed material recorded on the recording medium is reproduced at the transfer rate at the time of input and externally transferred, so that the increase in hardware scale does not lead to an increase in product cost. Material transfer exceeding 1 × speed can be realized. Further, in the compression method conversion process, the compressed material recorded on the recording medium is reproduced by the first transfer means using the idle time when the recording medium is not accessed for recording and reproduction, and the compressed material reproduced is compressed. Since the system is converted into a different compression system and re-recorded on the recording medium, the compression system can be converted without increasing the product cost due to an increase in hardware scale. Further, in the second transfer step, the compressed material of a different compression method re-recorded on the recording medium by the compression method conversion step is reproduced and externally transferred, so that although it lacks real-time properties, it matches the compression method of the transfer destination. The compressed material can be transferred, and compatibility between devices having different compression methods can be maintained.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a recording / reproducing apparatus according to an embodiment.

FIG. 2 is a block diagram showing a configuration of a modification.

FIG. 3 is a diagram for explaining a conventional example.

FIG. 4 is a diagram for explaining a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Control part, 2 ... SDTI receiving part, 3 ... Selector, 4 ...
Transcoder, 5: recording buffer, 6: reproduction buffer, 7: SDTI transmission unit, 8: selector, 9: selector, 10: material transfer processing unit, 20: recording / reproduction processing unit, 3
0 ... RAID part.

Claims (4)

[Claims] 1. A transfer means for recording a compressed material input at a transfer rate exceeding at least 1 × speed on a recording medium, and then reproducing the compressed material recorded on the recording medium at a transfer rate at the time of input and transferring the compressed material externally. And a compression method conversion means for reproducing the compressed material recorded on the recording medium by the transfer means, converting the compression method of the reproduced compressed material into a different compression method, and re-recording the compressed material on the recording medium. Characteristic recording / reproducing device. 2. A method in which a compressed material input at a transfer rate exceeding at least 1 × speed is recorded on a recording medium, and the compressed material recorded on the recording medium is reproduced at an input transfer rate and externally transferred. And reproducing the compressed material recorded on the recording medium by the first transfer device using the idle time of access to the recording medium, and converting the compression method of the reproduced compressed material to a different compression method. Compression method conversion means for re-recording the recording material on the recording medium, and second transfer means for reproducing the compressed material of a different compression method re-recorded on the recording medium by the compression method conversion means and externally transferring the compressed material. A recording / reproducing apparatus characterized in that: 3. A transfer process in which after a compressed material input at a transfer rate exceeding at least 1 × speed is recorded on a recording medium, the compressed material recorded on the recording medium is reproduced at an input transfer rate and externally transferred. And reproducing the compressed material recorded on the recording medium by the transfer process, converting the compression method of the reproduced compressed material to a different compression method, and re-recording the compressed material on the recording medium. Characteristic recording / reproducing method. 4. A first method in which a compressed material input at a transfer rate exceeding at least 1 × speed is recorded on a recording medium, and then the compressed material recorded on the recording medium is reproduced at an input transfer rate and externally transferred. And reproducing the compressed material recorded on the recording medium in the first transfer process using the idle time of access to the recording medium, and changing the compression method of the reproduced compressed material to a different compression method. A compression method conversion step of converting and re-recording on the recording medium; and a second transfer step of reproducing and externally transferring a compressed material of a different compression method re-recorded on the recording medium by the compression method conversion step. A recording / reproducing method, comprising: