JPH1031559A - Bit stream storage reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the capacity of temporary storage files which are formed in a high speed accumulation part and to shorten whole processing time by executing temporary storage into a high speed bit stream accumulation part and shift to a low speed bit stream executing final preservation in parallel. SOLUTION: A bit stream generation part 102 digitally converts video information from a video camera 101 and generates a bit stream. A temporary bit stream storage part 105 divides bit data stream data into prescribed sizes and stores them in the high speed bit stream accumulation part 103 as the temporary bit stream files 106. A book bit stream storage part 107 reads the head part of the bit stream stored in the high speed bit stream accumulation part 103, stores the bit stream which is read in the low speed bit stream accumulation part 104 and eliminate the bit stream whose storage is completed from the high speed bit stream accumulation part 103.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bit stream storing / reading apparatus for a bit stream which is continuous bit information, and more particularly, to a processing speed of a bit stream in a multimedia application in which moving image and audio data are digitized. The present invention relates to a configuration of a device suitable for such a case.

[0002]

2. Description of the Related Art With the improvement of computer processing capability,
Even relatively inexpensive, popular home personal computers can handle so-called multimedia data such as audio and video that could not be processed conventionally. In addition, storage devices for storing such data have been steadily becoming larger in capacity and cheaper.

[0003] However, multimedia data such as moving images in particular is basically bit information (bit stream) without any interruption, and the amount of data per unit time (bit rate) is specified for transfer. Therefore, it is necessary to adopt a data processing method different from that of files such as characters and still images generally used in conventional computer systems.

Devices such as a magneto-optical disk and a phase-change optical disk can easily exchange a large-capacity and relatively inexpensive portable medium, and can record a large amount of data such as still images such as CG. It has been widely used in recent years. But,
Since it is difficult for these devices to read and write at a large bit rate, it is not suitable for direct processing of data requiring a large bit rate such as a moving image.

On the other hand, a device capable of reading and writing data at a large bit rate, such as a hard disk, is often relatively expensive, difficult to exchange media, or poor in portability. Although there is a replaceable or portable hard disk drive, it is hard to say that it is superior in terms of media price, ease of replacement, portability, etc. as compared with the above-mentioned magneto-optical disk.

When processing image data and the like on a multimedia personal computer or the like, the hard disk drive generally stores an operation system, various utilities and application software, and various data and the like based on the software. Often used, large data occupies a large amount of hard disk space, or that you have to leave a large amount of space for work space,
In some cases, it is not desirable as a main storage device of a general-purpose personal computer.

Therefore, when using a storage device having only a reading and writing capability at a small bit rate, such as a magneto-optical disk or a phase-change optical disk, for a bit stream information requiring a large bit rate such as a moving image. In addition, there is a device for processing by combining a storage device capable of processing at a large bit rate such as a hard disk.

[0008] Such a conventional bitstream storage / reading device according to the prior art will be described below in the case of storing and reading. First, in a conventional bit stream storage / readout device, when a bit stream is generated at a large bit rate as in the case of video capture, this bit stream information is transferred to a small bit rate such as a magneto-optical disk or a phase change optical disk. A case where the information is stored in a storage device that can be stored only by using the method described above without causing a problem such as a loss of information will be described with reference to the drawings.

FIG. 18 is a diagram for explaining a conventional bit stream storage / readout device. In the figure, 1801
Denotes a video camera, which captures video information. 1802
Is a bit stream generator, and the video camera 180
The video information fetched from 1 is converted into digital data to generate a bit stream as a continuous bit string. 1
Reference numeral 803 denotes a high-speed bit stream storage unit, which is generally realized by a hard disk device or the like, can store a bit stream at a higher speed than the bit stream generation unit 1802 generates, and stores the bit stream generated by the bit stream generation unit 1802. It serves as a buffer for the low-speed bit stream storage unit 1805 that cannot be directly stored. Reference numeral 1804 denotes a bit stream file in which the bit stream data generated by the bit stream generation unit 1802 is temporarily stored in the high-speed bit stream storage unit 1803. Reference numeral 1805 denotes a low-speed bit stream storage unit, which is generally realized by a magneto-optical disk device or a phase-change optical disk device, and has the advantages of being inexpensive, portable, and large in capacity. The writing speed is inferior to that of a hard disk or the like. Since the writing speed is lower than the speed generated by the bit stream generator 1802, the bit stream cannot be stored directly. Reference numeral 1806 denotes a bit stream file. The bit stream data generated by the bit stream generation unit 1802 is finally stored in the low-speed bit stream storage unit 1805 for the purpose of storage.
Is stored in.

FIG. 2A shows a temporal change in the size of the bit stream file created in the high-speed bit stream storage unit in the storage operation of the bit stream storage / readout apparatus according to the conventional example and the embodiment of the present invention. Is represented by a graph. A shows the present invention, and B shows the change in file size in the conventional device.

FIG. 1 shows the operation of the conventional device when storing a bit stream while considering the transition of the file size.
8 and the graph of FIG. Here, it is assumed that a bit stream of video information requiring a bit rate of 600 Kbytes / sec (4.8 Mbps) is stored for 10 minutes, and the low-speed bit stream storage unit is 200 kbytes / sec.
It has a write speed of (1.6 Mbps) bit rate.

First, when video capture starts, the video camera 1801 captures video information, and this video information is sent to the bit stream generator 1802. The bit stream generator 1802 converts the video information into a digital signal, Data is output at a bit rate of 600Kbytes / sec. The output bit stream data is stored in the high-speed bit stream storage unit 1803.
Is stored as a bit stream file 1804. During this storage, the file size of the bitstream file 1804 increases over time. This stage continues while capturing the video and generating the bit stream (X section in FIG. 2A).

[0013] When the video camera stops operating and capture of video information ends, and the bit stream generation unit 1802 stops generating the bit stream, the storage in the high-speed bit stream storage unit 1803 ends. Is read out and stored in the low-speed bit stream storage unit 1805 at 200 Kbyte / sec. That is, since the bit stream file 1804 is copied between the high-speed bit stream storage unit 1803 and the low-speed bit stream storage unit 1805, the bit stream file 1804 is maintained during the copy, and the file size does not change. This step continues until the copying of the file is completed (P section B in FIG. 2A).

When the storage of the bit stream file 1806 in the low-speed bit stream storage unit 1805 is completed, the bit stream file 1804 in the high-speed bit stream storage unit 1803 is deleted. Since the deletion of the file only deletes the file management information, it ends instantaneously.

Free space (maximum size of provisionally created file) required for a high-speed bit stream storage unit when storing a bit stream by a conventional device;
The processing time until the final storage is completed is as follows.

Since all the generated bit streams are stored in the provisional bit stream file, the bit stream of video information having a bit rate of 600 Kbytes / sec (4.8 Mbps) is 10 minutes. × 10min × 60sec = 360,000Kbytes = 360M
A bit stream storage unit with a high free space of bytes is required.

Regarding the processing time, the amount of data is 360M, which is 200 kbytes / sec (1.6 Mbps).
In order to store the data in a low-speed storage unit having a writing speed of 360000Kbytes / 200Kbytes / sec = 1800sec = 30min, it takes 30 minutes to write the data. The time required for capturing the video, 10 minutes (writing to the high-speed storage section is almost completed within this capturing time) is added to this, and the result is 10 min + 30 min = 40 min. Therefore, a total of 40 minutes to capture a 10-minute video
Takes minutes.

Next, in the conventional bit stream reading apparatus, bit stream information requiring a large bit rate such as a moving image can be read only at a small bit rate such as a magneto-optical disk or a phase change optical disk. A case where data is read from a non-storage device and reproduced without interruption will be described below with reference to the drawings.

FIG. 19 is a diagram for explaining a conventional bit stream storage / readout device. In the figure, 1901
Is a monitor for reproducing video information. Reference numeral 1902 denotes a bit stream processing unit which processes the bit stream and converts it into original video information. Reference numeral 1903 denotes a high-speed bit stream storage unit, which is generally realized by a hard disk device or the like, and is capable of reading at a bit rate required by the bit stream processing unit 1902 for continuous reproduction, and the bit rate And serves as a pre-read buffer for reading from the low-speed bit stream storage unit 1905 that cannot be directly read. Reference numeral 1904 denotes a bit stream file in which bit stream data read from the low-speed bit stream storage unit 1905 is temporarily stored in the high-speed bit stream storage unit 1903. Reference numeral 1905 denotes a low-speed bit stream storage unit, which is generally realized by a magneto-optical disk device or a phase-change type optical disk device, and has the advantages of low cost, portability, and large capacity. The writing speed is inferior to that of a hard disk or the like, and the bit stream cannot be read at the bit rate required by the bit stream processing unit 1902. Reference numeral 1906 denotes a bit stream file in which video information is stored as bit stream data in the low-speed bit stream storage unit (1905) for storage.

FIG. 4A shows a temporal change in the size of the bit stream file created in the high-speed bit stream storage unit in the read operation of the bit stream storage / read apparatus according to the conventional example and the embodiment of the present invention. Is represented by a graph. A shows the present invention, and B shows the change in file size in the conventional device.

The operation of the conventional apparatus will be described below with reference to the graphs of FIGS. 19 and 4 (a) while considering the change in the file size. Here, 600Kbytes / sec (4.8Mbps
), A bit stream of video information having a size of 360 Mbytes is reproduced, and the low-speed bit stream storage section has a read speed of a bit rate of 200 kbytes / sec (1.6 Mbps).

At the time of reproduction, first, the bit stream file 1906 of the low-speed bit stream storage unit 1905
Is read at 200 kbytes / sec and all are stored in the high-speed bit stream storage unit 1903. During this time, the file size of the bit stream file 1904 increases. This step continues until all the bit stream files 1906 have been read (Q section B in FIG. 4A).

The high-speed bit stream storage unit 19
When the storage of the bit stream file 1904 into the bit stream file 03 is completed, the bit stream file 1904 is read out, and 600 Kbytes / sec.
To output. Since the bit stream file 1904 is only read, the file size does not change. This stage continues while the entire bit stream is output as video information, that is, for the video playback time (FIG. 4).
(R section of B in (a)). Bit stream processing unit 190
2 processes the read bit stream, converts it into original video information, and outputs it to the monitor 1901.

When the reproduction is completed, the bit stream file 1904 in the high-speed bit stream storage unit 1903 is deleted. Since the deletion of the file only deletes the file management information, it ends instantaneously.

Free space (maximum size of a file created temporarily) required for a high-speed bit stream storage unit when reading a bit stream by a conventional apparatus, and processing time until reading and reproduction are completed Is as follows.

First, as for the free space, all bit streams are temporarily stored in the provisional bit stream file in the high-speed bit stream storage unit, so that the original bit stream size of 360 Mbytes is required.

Regarding the processing time, it is necessary to take out data from a low-speed storage unit having a write rate of 200 kbytes / sec (1.6 Mbps) and copy the data before reproducing the video. Since the writing to the storage unit is fast, the delay due to this is ignored, and 360000Kbytes / 200Kbytes / sec = 1800sec = 30min is required.

The video playback time is 360 Mby
360000Kbytes because tes is processed at 600Kbytes / sec
÷ 600Kbytes / sec = 600sec = 10min Therefore, it takes 10min + 30min = 40min to play back 10 minutes of video, of which 30 minutes is pure (no video playback) waiting time.

[0029]

In the conventional storage by the bit stream storage and reading device, a high-speed bit stream is stored in a low-speed bit stream storage unit which can write data only at a lower speed than the bit stream generation unit. It was necessary to store all bitstreams once in the stream storage, and then copy all bitstreams to the low-speed bitstream storage. For this reason, the high-speed bit stream storage unit that temporarily stores the bit stream needs a large free space sufficient to store the entire bit stream. As described above, it is not desirable that a device such as a hard disk used as a high-speed bit stream storage unit take up too much capacity.

Further, after temporarily storing the bit stream, copying the bit stream to the low-speed storage unit requires an extra copy time in addition to the time required for video capture, so that the entire processing time is also reduced. become longer.

In the reading by the conventional bit stream storage and reading device, in order to read a bit stream from a low-speed bit stream storage unit that can only read at a lower speed than the bit rate required by the bit stream processing unit, the bit stream is temporarily stored in the high-speed bit stream storage unit. All the bitstreams had to be stored and then read out at the required bit rate to play the bitstreams seamlessly. Therefore, as in the case of storage, a large free space is required in the high-speed bit stream storage unit.

In addition, in order to pre-read the bit stream from the low-speed storage unit, a copy time is required in addition to the image reproduction time, so that the entire processing time is increased and the user is required to read the image before the image reproduction. There was a problem that waiting time occurred.

The present invention has been made to solve these problems in the conventional bit rate storage / readout apparatus, and reduces the free space required for a high-speed storage unit for temporarily storing a bit stream. It is another object of the present invention to provide a bitstream storage / readout device that can reduce the overall processing time.

[0034]

According to the first aspect of the present invention, there is provided an apparatus for storing and reading a bit stream which is continuous bit information obtained by digitizing a video and an audio. A bit stream generation unit that digitizes and generates a bit stream; a low speed bit stream storage unit that stores the bit stream at a lower speed than the bit stream generation unit generates the bit stream; A high-speed bit stream storage unit that stores a bit stream at a speed higher than the speed at which the bit stream is generated; a provisional bit stream storage unit that stores the bit stream generated by the bit stream generation unit in the high-speed bit stream storage unit; The bitstream storage is It reads the head of the bit stream stored in the serial high-speed bit stream storage unit,
A bit stream storage unit for storing the read bit stream in the low-speed bit stream storage unit and deleting the bit stream that has been stored in the low-speed bit stream storage unit from the high-speed bit stream storage unit. It is characterized by the following.

According to a second aspect of the present invention, there is provided an apparatus for storing and reading a bit stream which is continuous bit information obtained by digitizing video and audio, wherein the bit stream which is digital information is processed into a video and audio signal. A stream processing unit and a bit stream are stored therein,
When reading the stored bit stream, the read speed is lower than the speed at which the bit stream processing unit processes the bit stream, and the low-speed bit stream storage unit stores the bit stream. A high-speed bit stream storage unit whose read speed is higher than the speed at which the bit stream processing unit processes the bit stream; a provisional bit stream read unit that reads a bit stream from the low-speed bit stream storage unit and stores the bit stream in the high-speed bit stream storage unit The speed of the difference between the bit stream speed required by the bit stream processing unit and the read speed of the low-speed bit stream storage unit, and the total time of the processing performed by the bit stream processing unit. The bit stream amount obtained by multiplying the bit stream by the optimum bit rate is stored in the high-speed bit stream storage unit, and the bit stream is read out from the high-speed bit stream storage unit to store the bit stream. A bit stream reading unit for inputting the bit stream to the stream processing unit and deleting the bit stream input to the bit stream processing unit from the high-speed bit stream storage unit;

The invention according to claim 3 is based on claim 1.
In the bitstream storage / readout device described above, the high-speed bitstream storage unit manages stored data as a file, and the file management system uses a file management table and an area management table to store the file. To manage and handle a file based on a file name that identifies the file, first, the file name and the area start pointer indicating the start of the area management table for the area where the file data is stored are stored in the area management table. By referring to a file management table that enables reference, and then referring to an area management table that manages an area in the storage unit in which data of the same file is stored, an area in the storage unit in which data of the file is stored Can be known, Serial provisional bit stream storage unit,
The bit stream generated by the bit stream generation unit is divided into a predetermined size and stored as a plurality of files in the high-speed bit stream storage unit, and the present bit stream storage unit stores the file in the provisional bit stream storage unit. Reading out the bit stream stored as a file from the high-speed bit stream storage unit for each file, storing it in the low-speed bit stream storage unit, and deleting the file from the high-speed bit stream storage unit for each file. is there.

The invention according to claim 4 is based on claim 2.
In the bitstream storage / readout device described above, the high-speed bitstream storage unit manages stored data as a file, and the file management system uses a file management table and an area management table to store the file. To manage and handle a file based on a file name that identifies the file, first, the file name and the area start pointer indicating the start of the area management table for the area where the file data is stored are stored in the area management table. By referring to a file management table that enables reference, and then referring to an area management table that manages an area in the storage unit in which data of the same file is stored, an area in the storage unit in which data of the file is stored Can be known, Serial provisional bit stream reading unit, bit stream read out from the low speed bit stream storage unit is divided into a predetermined size stored in the high-speed bit stream storage unit as a plurality of files,
The bit stream reading unit reads the bit stream stored as a file by the provisional bit stream reading unit from the high-speed bit stream storage unit for each file, stores the bit stream in the low-speed bit stream storage unit, and The high-speed bit stream is deleted from the storage section.

Further, the invention according to claim 5 is the invention according to claim 3.
In the bit stream storage / readout device described above, the high-speed bit stream storage unit is capable of rewriting a file management table and an area management table for a part of a file in the file management system. A storage unit, wherein the provisional bit stream storage unit is a FIFO-compatible provisional bit stream storage unit that stores the bit stream generated by the bit stream generation unit as a file in the high-speed bit stream storage unit; A stream storage unit that reads the head of the file stored in the high-speed bit stream storage unit by the FIFO-compatible temporary bit stream storage unit, and stores this in the low-speed bit stream storage unit;
And a FIFO-compatible main bit stream storage for deleting information of an area used by the head of the file from the area management table and changing an area head pointer of the file information of the file in the file management table to a new position. Part.

The invention according to claim 6 is based on claim 4.
In the bit stream storage / readout device described above, the high-speed bit stream storage unit is capable of rewriting a file management table and an area management table for a part of a file in the file management system. A storage unit, wherein the temporary bit stream storage unit is a FIFO-compatible temporary bit stream storage unit that stores the bit stream generated by the bit stream generation unit as a file in the high-speed bit stream storage unit; The stream case reading is a FIFO-compatible provisional bit stream reading unit that stores the bit stream read from the low-speed bit stream storage unit as a file in the high-speed bit stream storage unit. Stream storage unit, the FIFO
The corresponding provisional bitstream reading unit reads the head of the file stored in the high-speed bitstream storage unit, inputs this to the bitstream processing unit, and stores the area used by the head of the file whose input has been completed. It is a FIFO-compatible type bit stream reading unit that deletes information from the area management table and changes the area start pointer of the file information of the file included in the file management table to a new position. .

The invention according to claim 7 is based on claim 1.
In the bit stream storage / readout device described above, the low-speed bit stream storage unit has a different storage speed depending on the storage position in the storage unit, and the storage speed is higher than the speed at which the bit stream generation unit generates the bit stream at the highest speed position. A speed change type bit stream storage unit having a feature that the bit stream generation unit is smaller than the speed at which the bit stream generation unit generates a bit stream at the position of the largest and the lowest speed, and the present bit stream storage unit is The bit stream stored in the high-speed bit stream storage unit is read, and the bit stream is stored first in a portion where the storage speed of the speed-change type bit stream storage unit is low. Completed bitstream The is characterized in that a speed change corresponding type present bit stream storage unit to be removed from the high-speed bit stream storage unit.

The invention according to claim 8 is the second invention.
In the bit stream storage and reading device described in the above, the reading speed of the low-speed bit stream storage unit differs depending on the storage position in the storage unit, and the reading speed is
A speed-variable bit stream storage unit characterized in that the bit stream processing unit is faster than the bit stream processing unit at the highest speed position, and smaller than the bit stream processing unit speed at the lowest speed position. The provisional bit stream reading unit reads out the bit stream first from a portion where the reading speed of the speed change type bit stream storage unit is high, and stores the bit stream in the high speed bit stream storage unit. It is a stream reading unit.

According to the ninth aspect of the present invention, there is provided the first aspect of the present invention.
The bitstream storage and readout device according to claim 1, further comprising two or more high-speed bitstream storage units, wherein at least one high-speed bitstream storage unit stores a bitstream and at least one high-speed bitstream storage unit reads a bitstream. And deleting operate simultaneously.

According to a tenth aspect of the present invention, in the bit stream storage / read device according to the second aspect,
Two or more high-speed bit stream storage units are provided, and the storage of the bit stream in at least one high-speed bit stream storage unit and the reading and deletion of the bit stream in the at least one high-speed bit stream storage unit operate simultaneously. It is characterized by having.

[0044]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. The bit stream storage and readout device according to the first embodiment of the present invention stores bit stream information having a large bit rate such as a moving image in a storage device (a magneto-optical disk or a phase change (A type optical disk or the like) so that troubles such as missing information do not occur.

FIG. 1 is a configuration diagram of a bit stream storage / read device according to Embodiment 1 of the present invention. In the figure, reference numeral 101 denotes a video camera which captures video information. Reference numeral 102 denotes a bit stream generation unit, which generates a bit stream by digitally converting video information captured by the video camera 101. A high-speed bit stream storage unit 103 is generally realized by a hard disk device or the like, and can store a bit stream at a higher speed than the bit stream generation unit 102 generates. Serves as a buffer for the low-speed bit stream storage unit 104 that cannot store the data. Reference numeral 104 denotes a low-speed bit stream storage unit, which is generally realized by a magneto-optical disk device or a phase-change optical disk device, and has the advantages of being inexpensive, portable, and large in capacity, but capable of reading a bit stream. In addition, the writing speed is inferior to that of a hard disk or the like, and the bit stream generated by the bit stream generating unit 102 cannot be directly stored.
Reference numeral 105 denotes a provisional bit stream storage unit that divides the bit stream data output from the bit stream generation unit 102 into a predetermined size, and stores the divided data as a provisional bit stream file 106 in the high-speed bit stream storage unit 103. Reference numeral 106 denotes a provisional bit stream file, which is composed of a plurality of files obtained by dividing the bit stream data into a predetermined size, and is given a file name by which the provisional bit stream storage unit 105 can determine the order. In this example, in order, 001,00
Using an extension with a serial number such as 2,003 ..., the file name is sequentially set to tempfile. 001, tempfil
e. 002, tempfile. 003. Reference numeral 107 denotes the present bit stream storage unit, which reads out the temporary bit stream file 106 sequentially in numerical order, stores the contents in the low-speed bit stream storage unit 104 as the bit stream file 108, and stores the temporary bit stream file 1 which has been stored.
06 are sequentially deleted from the high-speed bit stream storage unit 103.

FIG. 2A is a graph showing a temporal change in the size (file size) of the provisional bit stream file created in the high-speed bit stream storage unit in the storage operation of the bit stream storage and reading device. It is. A of FIG. 2A is a graph of a temporal change in the total amount of the provisional bit stream file 106 created in the high-speed bit stream storage unit 103 in the operation of the apparatus according to the first embodiment. B is a high-speed bit stream storage unit 180 in the conventional device already described.
3 is a change in the size of the bit stream file 1806 created in FIG. (B) is an enlarged view of a part of the graph A in (a).

The operation of the bit stream storing / reading apparatus according to the first embodiment configured as described above will be described with reference to FIG.
This will be described below with reference to FIG. As in the case of the conventional apparatus, a bit stream of video information having a bit rate of 600 Kbytes / sec (4.8 Mbps) is stored for 10 minutes, and the low-speed bit stream storage unit stores 20 bits.
It shall have a writing speed of a bit rate of 0 kbytes / sec (1.6 Mbps). The predetermined size of the provisional bit stream file created by dividing the bit stream is set to 20 Mbytes.

When the video camera 101 captures video information, and this information is sent to the bit stream generation unit 102, the bit stream generation unit 102 converts the video information into digital data and generates 600 Kbytes as bit stream data.
Output at a bit rate of s / sec. The outputted bit stream data is stored in the provisional bit stream storage unit 1.
05 and the input amount is a predetermined size 20
Every time it reaches Mbytes, the provisional bitstream storage unit stores this in the high-speed bitstream storage unit 103 as a provisional bitstream file 106 with a serial number added to the file name. The order in which the files are stored is given to the serial number of the file name. Thus tempfile.00
A file with a sequential number extension is created in the order of 1, tempfile.002, tempfile.003 ... The storage of the bit stream information in the provisional bit stream file by the provisional bit stream storage unit 105 is repeated until the capture of the video information ends and the bit stream generation unit 102 stops generating the bit stream.

On the other hand, the bit stream storage unit 107 first stores the first provisional bit stream file,
When file.001 is stored, this file is read out, stored as a bitstream file 108 in the low-speed bitstream storage unit 104, and then the first provisional bitstream file tempfile.001 is deleted from the high-speed bitstream storage unit.

Thereafter, the bit stream storage unit 107
When at least one or more provisional bit stream files 106 are stored, the file having the smallest serial number is read out and the contents are added to the bit stream file 108 of the low-speed bit stream storage unit 104. Further, the bit stream storage unit stores the provisional bit stream file 106 that has been read and stored.
From the high-speed bit stream storage unit 103. In this example, tempfile.002 and tempfile.003 are read in this order, added to the bit stream file 108, and deleted.

The reading, storing, and deleting operations by the bit stream storage section are repeated until all the temporary bit stream files 106 are exhausted.

The file size of the provisional bit stream file 106 shown in FIG. 2A will be described below. The bit stream data generated by the bit stream generation unit 102 is
06, the number of temporary bit stream files increases, but at the same time, the bit stream storage unit 10
7, the deletion is performed following the reading by
The file size is increased by the difference between the generation of the bitstream and the storage in the temporary bitstream file, and the reading and deletion of the temporary bitstream file.

That is, the difference 600 kbytes / sec-200 kbytes / sec = 400 kbytes / sec between the bit rate at which the bit stream is generated and the bit rate at which the bit stream is stored in the low-speed bit stream storage unit is almost equal to the increase rate of the file size. For 100 seconds, 400Kbytes / sec × 100sec = 40000Kbytes = 40Mbytes, which means that two provisional bit stream files of 20Mbytes increase.

Therefore, as shown in FIG. 2B, three provisional bit stream files 106 each having a file size of 20 Mbytes (tempfile.001, tempfile.002,
While the temporary file (tempfile.00) is created, one of the earliest temporary bitstream files (tempfile.001) is read out by the present bitstream storage unit, stored in the low-speed bitstream storage unit 104, and the storage is completed. It will be deleted when you do. This stage continues while the video is being captured (section X in FIG. 2A).

When the capturing of the video and the generation of the bit stream are completed, after the last provisional bit stream file is stored in the high-speed bit stream storage unit, only the deletion following the reading by the bit stream storage unit 107 is performed. File size is reduced. This reduction rate substantially follows the bit rate at which the low-speed bit stream storage unit 104 stores data. This operation continues until all the files are read and deleted (section Y in FIG. 2A).

As described above, the generated bit stream information is stored as a provisional bit stream file as a file divided into the high-speed bit stream storage unit, and is sequentially moved to the low-speed bit stream storage unit.
Deleted.

According to the bit stream storage / readout apparatus of the first embodiment, the provisional bit stream storage unit and the bit stream storage unit temporarily store the bit stream, that is, the high-speed bit stream storage unit 103.
And the transfer to the storage unit for final storage, that is, the transfer to the low-speed bit stream storage unit 108, are performed in parallel, so the temporary storage file created in the high-speed storage unit And the overall processing time can be reduced. This effect is shown by the difference between graphs A and B in FIG.

That is, in the case of the device of the first embodiment,
The free space required for the high-speed bit stream storage unit 103 is calculated from (600−200) Kbytes / sec × 10min × 60sec = 240000Kb based on the increase rate of the file size and the capture time.
ytes = 240Mbytes. Furthermore, the time required for storage is such that after the first temporary bitstream file is written, writing to the low-speed storage unit starts, but it takes only a short time to store the first temporary bitstream file. Therefore, the time required to write the total amount of the bit stream to the low-speed storage unit only needs to depend on the bit rate of the low-speed storage unit 108, 600Kbtes / sec × 10min × 60sec ÷ 200Kbytes / sec = 1800
sec = 30min.

According to the apparatus of the first embodiment, the free space required for the high-speed bit stream storage unit is about 67% of the 360 Mbytes required for the already-described conventional apparatus.
The total processing time is 75% compared to 40 minutes of the conventional equipment.
Only needs to be done.

The above description of the operation is theoretical, and in actuality, creation of a provisional bit stream file,
The above-mentioned theoretical value cannot be achieved because of the time required for reading and deleting, and the overhead due to the fact that access to the high-speed bit stream and the low-speed bit stream cannot be performed completely in parallel. However, the overhead reduction to the effectiveness of the present invention is not really significant.

For example, on the operating system “Windows95” sold by Microsoft Corporation in the United States, the device of the first embodiment is a hard disk device for the high-speed bit stream storage unit, and the writing speed of the low-speed bit stream storage unit is 1.8 Mbps. 512K for the above optical disc
When a bytes / sec bit stream is stored for 25 seconds, writing to the high-speed bit stream storage unit (hard disk) and writing to the low-speed bit stream storage unit are performed in the video capture section (X section in FIG. 2). We were able to do it at a bit rate of 1.5Mbps. From this, the difference from the theoretical value due to the overhead is not significant, and the effect of the apparatus of the present invention is not significantly impaired.

In the apparatus of the first embodiment, a secondary storage device such as a hard disk is used as a high-speed bit rate storage unit. However, the high-speed bit rate storage unit is limited to such means. However, any memory having a sufficient size can be used as a high-speed bit rate storage unit.

Embodiment 2 The bitstream storage and readout device according to the second embodiment of the present invention stores bitstream information having a large bitrate such as a moving image in a storage device (a magneto-optical disk or a phase change Read from an optical disk, etc.) and played back without interruption.

FIG. 3 is a configuration diagram of a bit stream storage / read device according to the second embodiment of the present invention. FIG.
Reference numeral 301 denotes a monitor, which displays video information. 30
A bit stream processing unit 2 processes the bit stream, converts the bit stream into original video information, and outputs the information to a monitor. Reference numeral 303 denotes a high-speed bit stream storage unit, which is generally realized by a hard disk device or the like, and can read a bit stream at a bit rate required by the bit stream processing unit 302. And serves as a look-ahead buffer for the low-speed bit stream storage unit 304 that cannot be read directly from the memory. Reference numeral 304 denotes a low-speed bit stream storage unit, which is generally realized by a magneto-optical disk device or a phase-change type optical disk device, and has the advantages of low cost, portability, and large capacity. Although used for storage as information, the bit stream write rate and read rate are inferior to those of a hard disk or the like.
Cannot read at the required bit rate. 30
Reference numeral 7 denotes a provisional bit stream reading unit that divides the bit stream file 308 read from the low-speed bit stream storage unit 304 into a predetermined size, and stores the divided bit stream file 306 as a temporary bit stream file 306 in the high-speed bit stream storage unit 303. Reference numeral 306 denotes a provisional bit stream file, which is obtained by dividing the bit stream data into a predetermined size. The method of naming the file is the same as in the first embodiment. 305
Is a bit stream reading unit for reading the provisional bit stream file 306 in order of serial numbers, sending the contents to the bit stream processing unit 302, and sequentially deleting the provisional bit stream file 306 that has been sent from the high-speed bit stream storage unit 303. I do.

FIG. 4 is a graph showing a temporal change in the size of the bit stream file created in the high-speed bit stream storage unit in the reading operation by the bit stream storage / read device. FIG.
A of (a) is an operation of the device according to the second embodiment.
6 is a graph showing a temporal change in the total size of the temporary bit stream file 306 created in the high-speed bit stream storage unit 303; B is a high-speed bit stream storage unit 190 in the conventional device already described.
3 is a change in the size of the bit stream file 1906 created in FIG. (B) is an enlarged view of a part of the graph A in (a).

The operation of the bit stream storage / read device according to the second embodiment configured as described above will now be described with reference to FIG.
This will be described below with reference to FIG. As in the case of the conventional device, here, it is assumed that a bit stream of video information having a bit rate of 600 Kbytes / sec (4.8 Mbps) and a size of 360 Mbytes is reproduced, and the low-speed bit stream storage unit stores 200 kbytes / sec (1.6 Mbps) bit rate. The predetermined size of the provisional bit stream file created by dividing the bit stream is set to 20 Mbytes.

When the reproduction is started, first, the provisional bit stream reading unit 307 reads the bit stream file 3
08 is read from the low-speed bit stream storage unit 304 and every time it is read up to a predetermined size of 20 Mbytes,
A serial number is assigned to the temporary bit stream file 306 and stored in the high-speed bit stream storage unit 303. As in the first embodiment, tempfile.001, tempf
ile.002, tempfile.003 ... and so on. This operation by the provisional bitstream storage is performed by the bitstream file 308.
Is repeated until all are read.

This bit stream reading unit 305
When the storage of the provisional bit stream file 306 is started, the optimal prefetch amount is calculated. This optimal look-ahead amount is
This is an amount obtained by multiplying the difference between the bit rate requested by the bit stream processing unit 302 and the bit rate readable by the low-speed bit stream storage unit 304 by the reproduction time of the video stored in the bit stream file 308. . The playback time in this case is 360 Mbytes / 600 Kbytes / sec = 600 sec = 10 min because the size is 360 Mbytes and the bit rate is 600 Kbytes / sec. Therefore, the bit rate requested by the bit stream processing unit 302 (the same as the bit rate of the video information) is 600 Kbytes / sec, and the bit rate that can be read from the low-speed bit stream storage unit 304 is 200 Kbytes / se.
From c and the above playback time, the optimal prefetch amount is (600Kbytes / sec-200Kbytes / sec) x 600sec = 240000Kbyte
s = 240 Mbytes, and the bit stream storage unit waits until the total amount of the provisional bit stream file 306 reaches the optimal prefetch amount of 240 Mbytes.

During this time, the bit stream file 30
The total file size of 6 continues to increase according to the bit rate at which the low-speed bit stream storage unit 304 reads data until the optimum prefetch amount is reached (X section in FIG. 4).

Then, the provisional bit stream file 3
06 reaches the above-mentioned amount of 240 Mbytes, the bit stream reading unit reads the file with the smallest serial number from the provisional bit stream file 306, and sends the contents to the bit stream processing unit 302. Bit rate 600Kbytes /
The provisional bit stream file 306 that has been transmitted in sec and has been transmitted is deleted from the high-speed bit stream storage unit 303.

During this time, the bit stream file 30
For the total file size of 6, the file size is reduced substantially according to the difference between the bit rate requested by the bit stream processing unit 302 and the bit rate readable by the low-speed bit stream storage unit 304.

That is, the difference between the bit rate at which the bit stream is processed and the bit rate at which the bit stream is read from the low-speed bit stream storage unit is 600 Kbytes / sec-200 kbytes / sec = 400 Kbytes / sec. Is 400Kbytes / sec × 100sec = 40000Kbytes = 40Mbytes, which means that two provisional bit stream files of 20Mbytes are reduced.

As shown in FIG. 4B, three provisional bit stream files 106 having a file size of 20 Mbytes in 100 seconds (tempfile.001, tempfile.002, tempfile.0)
0) During deletion, one file (tempfile.014) is created.

This stage continues until the provisional bit stream file 306 completely disappears. However, the time when the provisional bit stream file 306 completely disappears and the time when the reproduction of the video ends are almost the same (FIG. a) Y
section).

The bit stream processing unit 3 to which the bit stream is sent from the bit stream reading unit 305
02 processes this bit stream and converts it into video information, which is displayed on the monitor 301. A bit stream reading unit, a bit stream processing unit,
These operations on the monitor are repeated until all the temporary bit stream files 306 are exhausted, that is, until the reproduction ends.

In the bitstream storage / readout apparatus according to the second embodiment, the bitstream readout unit calculates the optimal prefetch amount and prefetches the bitstream. The pre-reading and the transmission of the bit stream are performed in parallel by the stream reading unit and the present bit stream reading unit. For this reason, the time for performing only read-ahead without transmitting the bit stream, that is, the time for which the user has to wait before playing can be greatly reduced as compared with the conventional method, and the playback of the video and the reading of the bit stream can be performed. Can be ended at the same time.
Further, the capacity of the provisional file of the high-speed storage unit required for pre-reading can be reduced.

In the conventional device, the free space of the high-speed storage unit is
360Mbytes, the pure (without playback) waiting time was 30 minutes, but the required free space is the amount that the provisional bitstream file is maximized, that is, the optimal look-ahead amount of 240M
bytes, the time required for pure look-ahead is 240000Kbytes / 200Kbytes / sec = 1200sec = 20min, which is 20 minutes.

Therefore, according to the apparatus of the second embodiment of the present invention, the free space of the high-speed bit stream storage unit is only about 67% of the capacity required by the conventional technology, and the time of pure pre-reading until the reproduction of the video is completed. Even about the time required by the prior art
Only 67%.

In the description of the apparatus according to the second embodiment, as in the case of the first embodiment, the above-described effects are theoretical, and there is actually a reduction due to overhead due to the operation of the apparatus. However, similarly to the first embodiment, the reduction due to the overhead is not so significant, and the effect of the device of the second embodiment is not significantly impaired.

Also, as in the first embodiment, the high-speed bit rate storage section is not limited to a secondary storage device such as a hard disk. It can be used as a storage unit.

Embodiment 3 The bitstream storage / readout apparatus according to the third embodiment of the present invention manages a temporary file by a file management system compatible with FIFO and stores a bitstream.

In the bit stream storage / readout apparatus according to the first embodiment, a high-speed bit stream storage unit for storing a provisional bit stream file is used in accordance with a file management system generally used as a disk operating system in a personal computer or the like. Was something.

In order to use the provisional bit stream file as a buffer, its contents are added, and at the same time, the beginning is read and deleted (first-in first-out method, hereinafter referred to as FIF).
O), but a commonly used file management system appends (adds) the contents of the file.
Since it is impossible to delete the head during the operation, the first embodiment divides the bit stream into a plurality of provisional bit stream files and writes, reads, and deletes them in file units. And

However, the present invention is not limited to the configuration depending on such an existing file management system, but by changing the file management system,
It is possible to further enhance the effects of the present invention.

FIG. 5 shows Embodiment 3 of the present invention.
9 illustrates a file management system included in a high-speed bit stream storage unit. In the figure, reference numeral 503 denotes a file management table, which is represented as a table in which a pair of a file name and an area start pointer exists for each file. In order to know the area in the storage unit where the data of the file is stored, Used to refer to the area management table. Reference numeral 501 denotes a file name in the table, and 502 denotes an area start pointer in the table, which is a pointer indicating the start position of an area on a storage device (such as a disk) used by the file. 5
An area management table 04 manages the use state of the area on the storage device. As shown in the figure, for the file 501 whose file name is "tmpfile", the area start pointer of 502 is "0". Therefore, when referring to the area 0 of the area management table 04, the content is "1". It turns out that it becomes. This indicates that the area used by "tmpfile" uses area 1 next to area 0. Next, similarly, referring to the area 1 part of the area management table 504, since the content is "2", it can be understood that the next area is "2". As described above, the area management table 504 manages the area on the storage device used by the file in a list structure. The area "3" used by "tmpfile" has "-1", which is the area "3"
Indicates that "tmpfile" is the last area used.

The configuration of the bit stream storage / read device according to the third embodiment will be described below. FIG. 7 is a diagram showing the configuration of the device according to the third embodiment. In the figure, reference numeral 703 denotes a FIFO-compatible high-speed bit stream storage unit, which manages data by the FIFO-compatible file management system shown in FIG. Reference numeral 705 denotes a FIFO-compatible provisional bit stream storage unit, which converts the bit stream generated by the bit stream generation unit 102 into a single provisional bit stream file
It is stored in the FO-compatible high-speed bit stream storage unit 703. Reference numeral 707 denotes a FIFO-compatible main bit stream storage unit, which reads the head of the temporary file 706 and stores it in the low-speed bit stream storage unit 104, deletes the information of the area used by the head from the area management table 504, The area start pointer 50 of the file information of the file included in the file management table 503
Change 2 to a new position. Other reference numerals are the same as those in the first embodiment, and a description thereof will not be repeated.

FIG. 6 shows the operation of the file management system according to the operation of the bit stream storage / read device of the third embodiment.

The operation of the bit stream storage / read device according to the third embodiment will be described below with reference to FIGS. When the video camera 101 captures video information and the information is sent to the bit stream generation unit 102,
The bit stream generation unit 102 converts the video information into a digital signal and outputs it as bit stream data.

The output bit stream data is
When the total amount input to the FO-compatible provisional bit stream storage unit 105 reaches a predetermined size, the FIFO
By the O-compatible provisional bit stream storage unit 705,
First, the temporary bit stream file 706 is given a file name “tempfile” and stored in the FIFO-compatible high-speed bit stream storage unit 103, and thereafter, every time a predetermined amount is reached, the temporary bit stream file 70
6 is added at the end. This additional processing is performed by the FIFO
Writing of bit stream data to the compliant high-speed bit stream storage unit 103 and the area management table 6
This is performed by adding a new area to the end of the list structure in No. 04. The input to the provisional bit stream storage unit and the addition to the provisional bit stream file completes the capture of the video information.
This is repeated until 02 stops generating the bit stream.

When the storage of the provisional bit stream file is started, the FIFO-compatible type bit stream storage unit 707 stores the file name 6 in the file management table 603.
The data in the area pointed to by the area start pointer 602 corresponding to 01 "tempfile" is read out, and the contents are initially stored as the bit stream file 108 of the low-speed bit stream storage unit 104, and thereafter added to the bit stream file 108. . When the reading, storing, or adding is completed, the file management table 603
Of the area start pointer 602 in the area management table 6
04, the pointer is replaced with the pointer of the next area, and the area previously pointed to by the area start pointer 602 is set to "unused". The reading and addition by the bit stream storage unit and the rewriting of the file management table and the area management table are repeated until all the temporary bit stream files are exhausted.

In the bit stream storage / readout device according to the third embodiment, the provisional bit stream storage unit and the present bit stream storage unit must be of the FIFO compliant type in accordance with the FIFO-compatible file management system. Thus, the head portion of the file is deleted by changing the area start pointer without creating a plurality of provisional bit stream files. Therefore, the first embodiment for storing and deleting files in file units
As compared with the bit stream storage / readout apparatus of the first embodiment, writing to the file management table is reduced, the first-in first-out operation of the temporary bit stream file 706 can be realized with low overhead, and the effect of the present invention can be realized with high efficiency.

Embodiment 4 FIG. The bitstream storage / readout device according to the fourth embodiment of the present invention manages a temporary file by a file management system compatible with FIFO and reads out a bitstream.

In the device of the fourth embodiment of the present invention, the file management mechanism of the high-speed bit stream storage unit is the same as that of the device of the third embodiment, and the description in FIG. 5 will be omitted.

FIG. 8 is a diagram showing the configuration of the device according to the fourth embodiment. In the figure, reference numeral 803 denotes a FIFO-compatible high-speed bit stream storage unit, which manages data by the FIFO-compatible file management system shown in FIG. Reference numeral 805 denotes a FIFO-compatible main bit stream reading unit that reads the head of the temporary file 706 and inputs the read data to the bit stream processing unit 802.
The information of the area used by the head part is stored in the area management table 50.
4 and the file management table 503
Is changed to a new position in the area start pointer 502 of the file information of the above-mentioned file. Reference numeral 807 denotes a FIFO-compatible temporary bitstream storage unit which stores the bitstream read from the low-speed bitstream storage unit 304 as a single temporary bitstream file 806 in the FIFO format.
It is stored in the corresponding high-speed bit stream storage unit 803.
Other reference numerals are the same as those in the second embodiment, and a description thereof will not be repeated.

FIG. 6 shows the operation of the file management system according to the operation of the bit stream storage / read device according to the third embodiment.

The operation of the bit stream storing / reading apparatus according to the present embodiment will be described below with reference to FIGS. When the reproduction is started, first, the FIFO-compatible temporary bit stream reading unit 307 reads the bit stream file 308 from the low-speed bit stream storage unit 304 and reads out the bit stream file 308 to a predetermined size. Name
A temporary file is added to the temporary bit stream file 806 every time when a predetermined amount is reached after adding a tempfile to the high-speed FIFO compatible bit stream storage unit 803. This additional processing is performed by writing bit stream data to the FIFO-compatible high-speed bit stream storage unit 803 and adding a new area to the end of the list structure in the area management table 604. The input to the FIFO-compatible provisional bit stream reading unit and the addition to the provisional bit stream file are repeated until all the bit stream files 308 are read.

The calculation of the optimum prefetch amount by the FIFO-compatible main bitstream reading unit 805 and the waiting until the size of the temporary bitstream file 806 reaches the optimum prefetch amount are performed in the same manner as in the second embodiment.

When the size of the provisional bit stream file 806 reaches the optimum read-ahead amount, the FIFO-compatible main bit stream read unit reads the file management table 60
The data of the area pointed to by the area start pointer 602 corresponding to the file name 601 “tempfile” of No. 3 is read out, and the content is output to the bit stream processing unit 302. When the reading and the output are completed, the area start pointer 602 of the file management table 603 is replaced with the pointer of the next area by referring to the area management table 604, and the area pointed to by the area start pointer 602 is also changed. Make it "unused". The reading and output by the bit stream reading unit and the rewriting of the file management table and the area management table are repeated until all the temporary bit stream files are exhausted.

The bit stream processing by the bit stream processing unit 302 and the output to the monitor 301 are the same as in the second embodiment.

As described above, in the bit stream storage / readout device according to the fourth embodiment, the provisional bit stream storage unit and the present bit stream storage unit are FIFO-compatible, and the high-speed bit stream storage unit follows the FIFO-compatible file management system. Because of the type, a plurality of provisional bit stream files are not created, and the head of the file is deleted by changing the area start pointer. For this reason, compared to the bitstream storage / readout apparatus according to the second embodiment that stores and deletes files, the writing to the file management table is reduced, and the first-in first-out operation of the temporary bitstream file 806 can be realized with low overhead. Can,
The effect of the present invention can be realized with high efficiency.

Embodiment 5 FIG. In the device of the first embodiment,
Although a storage device having write and read capabilities that are always inferior to the bit rate required for the low-speed bit stream storage unit has been used, the fifth embodiment described below always requires a required bit rate. No,
In this case, a storage device that may be satisfied depending on conditions is stored as a bit stream storage unit corresponding to a low-speed bit stream storage unit according to the first embodiment. Note that such a storage device can be realized by some phase-change optical disks or the like.

FIG. 9 is a diagram for explaining, as an example of the storage device described above, a disk-type storage device in which the bit stream storage speed and the read speed differ depending on the data storage position. As shown in the graph, the storage / read speed of the disk 901 changes continuously depending on the storage position on the disk, and the required bit rate (BR in the graph of FIG.
2) Having the above storage / readout capability (BR2 to BR)
3) In the inner circumference, the storage / readout capability (BR1 to BR2) is lower than the required bit rate (BR2).

FIG. 14 is a diagram showing a configuration of a bit stream storage / read device according to the fifth embodiment. In the figure,
Reference numeral 901 denotes a speed change type bit stream storage unit, which is a disk of the storage device described in FIG. 9 and stores a bit stream file for final storage. Reference numeral 1407 denotes a speed change type main bit stream storage unit which stores bit stream data from the inner circumference to the outer circumference of the storage device 901 described with reference to FIG. 901
For components other than and 1407, Embodiment 1
And the description is omitted.

FIG. 6A is the same as the graph of FIG.
It shows the relationship between the storage position and the writing speed.
(B) is a graph showing a temporal change in the overall size of the provisional bit stream file 106 created in the high-speed bit stream storage unit 103 according to the fifth embodiment of the present invention.

The operation of storing a bit stream using the bit stream storage and reading device according to the third embodiment will be described with reference to FIGS. 10 and 14, and the file size of a provisional bit stream file created in a high-speed bit stream storage unit. This will be described below while considering the following.

The bit stream generation unit 102 generates bit stream data and the temporary bit stream storage unit 105 generates a temporary bit stream file 106.
Is the same as in the first embodiment.

Speed change type main bit stream storage unit 14
In step 07, the temporary bit stream file 106 is read out in the order of the number given to the file name and stored from the inner circumference to the outer circumference of the speed-variable bit stream storage unit 901. Then, the provisional bit stream file 106 that has been stored is deleted.

In the apparatus of the fifth embodiment, the speed-change-compatible bit stream storage unit 1407 starts storage from the inner periphery of the speed-change type bit stream storage unit, that is, the position where the bit stream storage rate is low. Therefore, initially, the provisional bitstream file 106
Is slowly added to and deleted from the bitstream file 108, and the overall size of the provisional bitstream file 106 increases significantly. (Point W of FIG. 6B, the slope of the tangent of the curved portion indicates the rate of increase or decrease of the file size, and the slope of the tangent at the point W is large.) Since the storage position of the stream file 108 is shifted from the inner circumference to the outer circumference of the storage device, that is, from a position where the bit stream storage rate is low to a position where the bit stream storage rate is high, the increase rate of the overall size of the provisional bit stream file 106 is gradually increased. Becomes smaller (W → X portion in FIG. 6B), and when the storage rate of the low-speed bit stream storage unit 104 and the generation rate of the stream generated by the bit stream generation unit 102 become equal, the provisional bit stream file The rate of increase in the overall size of 106 becomes 0 (FIG. 6B).
X point).

Further, the low-speed bit stream storage section 104
As the storage rate of the temporary bit stream file 106 increases, the amount of storage in the low-speed storage unit and deletion from the temporary file exceeds the amount of generation and storage in the temporary file. Gradually decreases (X → Y portion in FIG. 6B), and finally the file size becomes 0 (point Y in FIG. 6B).

Thereafter, the bit stream generator 102
Since the storage rate of the low-speed bit stream storage unit 104 is larger than the generation rate of the temporary bit stream storage unit 104, only one divided temporary file is created in the temporary bit stream file 106 for a very short time, and the size remains almost zero. , A bit stream is stored (Y → Z portion in FIG. 6 (b), and the video capturing time up to point Z is T).

As described above, in the bit stream storage / readout device according to the fifth embodiment, the expected bit rate (BR
2) A low-speed bit rate storage device having the above storage capacity (BR3 to BR2) but having only the storage capacity (BR1 to BR2) less than or equal to the expected bit rate (BR2) on the inner circumference, When the storage unit stores the bit stream, the storage unit performs an operation of storing from the inner circumference to the outer circumference of the storage device, that is, captures video information or the like because the storage unit operates so as to be able to store the data gradually. In this case, although the size of the provisional bit stream file initially increases, the size of the provisional bit stream file decreases as the storage position approaches the outer periphery, and after the size approaches 0, the provisional bit stream file contains It only accumulates for a very short time. After the video capture and the bit stream generation are completed, the last temporary file is only stored for a very short time, and almost immediately after the capture is completed, the transfer of this file is completed, and the entire process is completed.

For this reason, there is no Y section (the time for writing the contents of the provisional bit stream after the video capturing time X) in FIG. 2 which explains the size of the provisional bit stream file in the first embodiment, and the first embodiment is omitted. It is possible to further reduce the processing time as compared with the apparatus described above.

FIG. 11 is for explanation purposes, and does not depend on the fifth embodiment of the present invention.
7 is a graph illustrating a change in the size of the provisional bit stream file 106 when writing is performed from the outer circumference to the inner circumference of No. 1.

After the storage is started, only one temporary bit stream file is created in the high-speed bit stream storage section for a very short time, so that the size of the temporary bit stream file remains close to 0 (P in FIG. 7B). (→ Q part) is a point in time when the storage rate of the low-speed bit stream storage unit 104 and the generation rate of the stream generated by the bit stream generation unit 102 become equal (Q in FIG. 7B).
Point), the file size of the provisional file gradually increases (Q → R portion in FIG. 7 (b)). When the video capture is completed, only the temporary file is deleted, so the file size decreases (see R → in FIG. 7B).
S part) until all the temporary files are deleted (Fig. 7
(S point of (b)) The file size does not become 0. After all, it takes time to write data to the disk even after capturing the video (time U in FIG. 7B). Therefore, if it is not according to the fifth embodiment of the present invention (FIG. 11), the temporary file The time required for complete deletion (time T + time U) is longer than that according to the fifth embodiment of the present invention (time T in FIG. 6).

In the bit stream storage / readout device of the fifth embodiment, a speed change type bit stream storage unit having a different write speed depending on the storage position is used, and the speed change type bit stream storage unit is used by the speed change type bit stream storage unit. By starting storage in the storage unit from a portion where the writing speed is low and gradually storing it in a portion where the writing speed is high, it is possible to eliminate the writing time after capturing the video. The processing time can be further reduced.

Note that the graph of FIG.
Although it originally has a step-like shape like A in FIG. 2A, it is approximately displayed here by a curve. Theoretically, the smaller the size of the provisional bit stream file, the closer the stepwise polygonal line becomes to the curve in FIG.

In the fifth embodiment, the high-speed bit stream storage unit uses the same file management system as in the first embodiment, and a plurality of provisional bit stream files are created. It is also possible to combine with the mode according to the FIFO-compatible file management system shown in FIG.

Embodiment 6 FIG. Embodiment 6 of the present invention
A bit stream is read out using a speed-change type bit stream storage unit. FIG. 15 is a diagram showing the configuration of the bitstream storage / readout device according to the sixth embodiment. In the figure, reference numeral 901 denotes a speed change type bit stream storage unit, which has been described in the fifth embodiment, and stores a bit stream file 308 for the purpose of storage. Reference numeral 1507 denotes a speed-change-capable provisional bit stream reading unit,
Are read from the outer circumference to the inner circumference of the storage device 901 described in (1). Components other than 901 and 1507 are the same as those in the second embodiment, and a description thereof will be omitted. The bit stream information stored in the storage device 901 and read by the device according to the sixth embodiment of the present invention is stored from the outer periphery toward the inner periphery.

FIG. 12A is the same as FIG. 9A,
6 is a graph illustrating a relationship between a storage position and a writing speed.
(B) is a graph showing a temporal change in the overall size of the provisional bit stream file 306 created in the high-speed bit stream storage unit 303 according to the sixth embodiment of the present invention.

Embodiment 6 of the present invention configured as described above
Will be described below with reference to FIGS. 12 and 15, while considering the file size of a provisional bit stream file created in the high-speed bit stream storage unit.

When the reproduction is started, the speed-change-capable provisional bit stream reading unit 1507 reads the data of the low-speed bit stream storage unit 304 from the outer periphery, and divides the data into a provisional bit stream file 306 into a predetermined size. The data is stored in the high-speed bit stream storage unit 303. The file name of the temporary file is the same as in the first embodiment. The provisional bit stream file 306 by the bit stream reading unit 105
After that, the operation is the same as in the second embodiment.

In the apparatus according to the sixth embodiment, the speed-change-capable provisional bit stream reading unit 1507 determines the outer circumference of the speed-change-type bit stream storage unit 901, that is, the bit stream read rate that the bit stream processing unit 302 requests. Since reading is started from a position higher than the rate, the amount of storage is initially larger than the transmission and deletion of the provisional bit stream file 306, and the overall size of the provisional bit stream file 306 is significantly increased. (Point W in FIG. 8B. The inclination of the tangent indicates the rate of increase or decrease, as in the description of the fifth embodiment).

Since the speed change type provisional bit stream reading unit 1507 shifts the read position from the outer circumference to the inner circumference of the speed change type bit stream storage unit 901, that is, from the position where the bit stream reading rate is high to the position where it is low. The rate of increase in the overall size of the provisional bit stream file 306 gradually decreases (W → X portion in FIG. 8B), and the read rate of the bit rate storage unit 901 and the bit stream processing unit 302 When the processing rate becomes equal, the rate of increase in the overall size of the provisional bit stream file 306 becomes 0 (point X in FIG. 8B).

After this point, the amount of deletion from the provisional bit stream file 306 exceeds the amount of storage in the file, and the reading rate from the speed-variable bit stream storage unit 901 increases. As the size increases, the overall size of the provisional bit stream file 306 gradually decreases. This continues until the video playback time ends (X → Y portion in FIG. 8B). At the time when the video playback time ends, all the provisional bit stream files 306 are deleted (Z point in FIG. 8, the video playback time up to the Z point is R).

As described above, in the bit stream storage / read device according to the sixth embodiment, the read capability (B
R3 to BR2), and a speed-change-type bit rate storage unit having only a read capability (BR1 to BR2) equal to or less than the expected bit rate BR2 on the inner circumference. When reading a bit stream to a temporary file, by reading from the outer circumference toward the inner circumference, when playing back video information, etc., it is possible to read at a bit rate higher than the initially required bit rate. The pre-reading time as described in the second embodiment is almost zero, and the video can be reproduced almost immediately. Further, the read bit stream is stored as a provisional bit stream file until it is sent to the bit rate processing unit. Even if the read rate of the low-speed bit stream storage unit 304 becomes lower than the expected read rate, The provisional bit street file is used as a pre-reading part and is gradually consumed, so that continuous video reproduction can be performed.

FIG. 13 shows, for the sake of explanation, a rate-variable bit rate storage unit 901 regardless of the sixth embodiment.
7 is a graph showing a change in the size of a provisional bit stream file 306 when reading is performed from the inner periphery to the outer periphery of the temporary bit stream file 306. In this case, since the inner peripheral portion to be read first has a low reading rate and cannot reproduce the video as it is, the prefetching technique described in the second embodiment is used, and a temporary bit stream file is used in the second embodiment in advance. The apparatus operates so as to perform prefetching of the indicated amount (up to point P), and thereafter start reproduction of the video. In this case, by storing and sending the provisional bit stream file in parallel, it is possible to obtain the effect of improving the size of the provisional file and the overall processing time as compared with the conventional apparatus described in the second embodiment. However, the effect that the pre-reading time shown in the sixth embodiment becomes almost zero cannot be obtained.

In the bit stream storage / readout device of the sixth embodiment, a speed change type bit stream storage unit having a different write speed depending on the storage position is used, and a speed change type bit stream read unit is used for the speed change type bit stream read unit. By starting reading from a portion where the reading speed of the storage unit is fast, and gradually shifting to a portion where the reading speed is slow, it becomes possible to eliminate a pure waiting time before the video is reproduced. Further, the processing time can be reduced.

Note that the graph of FIG.
Although it originally has a step-like shape like A in FIG. 2A, it is approximately displayed here by a curve. Theoretically, the smaller the size of the provisional bit stream file, the closer the stepwise polygonal line to the curve of FIG.

Also, in the sixth embodiment, the high-speed bit stream storage unit is based on the same file management system as in the second embodiment, and a plurality of temporary bit stream files are created. It is also possible to combine with the mode according to the FIFO-compatible file management system shown in FIG.

Embodiment 7 FIG. The bitstream storage / readout apparatus according to the seventh embodiment of the present invention can further enhance the effects of the present invention with respect to bitstream storage by changing the hardware configuration of the high-speed bitstream storage unit. It is.

FIG. 16 is a diagram showing a configuration of a bit stream storage / read device according to the seventh embodiment. In the figure, reference numeral 1601 denotes a high-speed bit stream storage unit according to the seventh embodiment, which is constituted by a plurality of independently storable / readable disks. Reference numeral 1602 denotes a disk which stores and reads out a bit rate. Reference numeral 1603 denotes a head, and the disk 160
2 is provided for each of the two discs, and reads and writes data independently for each disc. A provisional bit stream storage unit 1604, a bit stream generation unit 1605, the present bit stream storage unit 1606,
The low-speed bit stream storage unit 1607 functions in the same manner as that described in the first embodiment, and a description thereof will be omitted.

The operation of the bit stream storage / read device according to the seventh embodiment will be described below with reference to FIG. When the bit stream generation unit 1605 converts the video information into a digital signal and outputs it as bit stream data, the output bit stream data is input to the provisional bit stream storage unit 1604, and the provisional bit stream storage unit outputs the high-speed bit stream storage unit. 16
01 is stored as a tentative bit stream file on the disk 1602 that constitutes the file. In the high-speed bit stream storage unit 1601, since the end point W of the provisional bit stream storage unit is connected to the head end point Y, the data of the provisional bit stream storage unit 1604 is stored on the disk A.

The bit stream storage unit 1606 first switches the connection between the end point W of the provisional bit stream storage unit, the end point X of the bit stream storage unit, and the end points Y and Z of the head, and sets W to Z and X to Y Connect to Then, the bit stream output from the provisional bit stream storage unit 1604 is stored on the disc B,
Independently of the operation of the disc B, the bit stream storage unit 1606 reads the bit stream written on the disc A and stores the read bit stream into the low-speed bit stream storage unit 1607.
To be stored. The bit stream storage unit 1606 deletes the stored bit stream data from the disk A.

Further, the present bit stream storage section 160
6 denotes an end point W of the provisional bit stream storage unit, an end point X of the present bit stream storage unit, end points Y and Z of the head.
, And connect W to Y and X to Z. Then, since the bit stream output from the provisional bit stream storage unit 1604 is stored on the disk A, the bit stream storage unit 1606 stores the bit stream written on the disk B independently of the operation of the disk A. Reads the stream and stores it in the low-speed bit stream storage unit 1
607. This bit stream storage unit 1606
Deletes the stored bit stream data from the disk B. The above operation is repeated until bit stream generation is completed.

As described above, in the bit stream storage / readout apparatus according to the sixth embodiment, the storage unit used by the provisional bit stream storage unit and the storage unit used by the present bit stream storage unit are switched by the switch. Since writing, reading, and erasing are performed independently, the first-in first-out (FIFO) of the temporary bit stream file can be performed more efficiently and with less overhead.
Operation can be realized. This makes it possible to further reduce the processing time.

Embodiment 8 FIG. The bitstream storage / readout apparatus according to the eighth embodiment of the present invention can further enhance the effects of the present invention for reading out a bitstream by changing the hardware configuration of the high-speed bitstream storage unit. It is.

FIG. 17 is a diagram showing a configuration of a bit stream storage / read device according to the eighth embodiment. In the figure, a high-speed bit stream storage unit 1701, a disk 1702, and a head 1703 are described in an eighth embodiment.
Is the same as

The provisional bit stream reading section 170
4. The low-speed bit stream storage unit 1705, the present bit stream reading unit 1706, and the bit stream processing unit 1707 are basically the same as those described in the second embodiment, and a description thereof will be omitted.

The operation of the bit stream storing / reading apparatus according to the eighth embodiment configured as described above is shown in FIG.
This will be described below with reference to FIG. When the bit stream data is read from the low-speed bit stream storage unit 1705, the read bit stream data is input to the provisional bit stream reading unit 1704, and the provisional bit stream reading unit configures the high-speed bit stream storage unit 1701. It is stored on the disk 1702. Since the end point W of the provisional bit stream reading unit is connected to the head end point Y, the data of the provisional bit stream reading unit 1704 is stored on the disk A.

This bit stream reading unit 1706
First, the end point W of the provisional bit stream reading unit,
The connection between the end point X of the present bit stream reading unit, the end points Y and Z of the head is switched, and W is connected to Z and X is connected to Y. Then, the provisional bit stream reading unit 17
04 is stored on the disk B, so that the bit stream output from the disk B is independent of the operation of the disk B.
The bit stream reading unit 1706 reads the disk A
, And outputs the bit stream to the bit stream processing unit 1707. The bit stream reading unit 1706 deletes the output bit stream data from the disk A.

Further, the present bit stream reading section 1
706 is an end point W of the provisional bit stream reading unit,
The connection between the end point X of the present bit stream reading unit, the end points Y and Z of the head is switched, and W is connected to Y and X is connected to Z. Then, the provisional bit stream reading unit 17
04 is stored on the disk A, so that the bit stream output from the disk A is independent of the operation of the disk A.
The bit stream reading unit 1706 reads the disk B
, And outputs the bit stream to the bit stream processing unit 1707. The bit stream reading unit 1706 deletes the bit stream data that has been output from the disk B. The process from output of the bit stream to the bit stream processing unit 1707 to processing and reproduction on the monitor is the same as in the second embodiment. The above operation is repeated until the read / reproduction is completed.

As described above, in the bitstream storage / readout apparatus according to the eighth embodiment, the storage section used by the provisional bitstream reading section and the storage section used by the present bitstream reading section are switched by the switch. Since the writing, reading, and erasing are performed independently, the first-in first-out (F / F) of the temporary bit stream file is more efficiently and with less overhead.
IFO) operation can be realized. Thereby, the processing time can be further reduced.

[0143]

According to the bit stream storing / reading device of the first aspect of the present invention, when storing a bit stream requiring a large bit rate in a storage device having a low writing speed, the provisional bit stream storage unit uses a high speed. In parallel with the storage of the temporary bit stream file in the buffer capable of supporting the temporary access, the temporary bit stream file is read out by the bit stream storage unit and stored in the low-speed storage device, and the temporary bit stream file is stored. The processed part can be deleted. This reduces the amount of buffer space required,
In addition, instead of waiting until all of the bit stream is temporarily stored in the buffer and then copying to the final storage unit as in the related art, reading is performed in parallel with storage, so that bit stream storage is completed. Processing time up to

According to the bit stream storage / read device of claim 2, when a bit stream requiring a large bit rate is read from a storage device having a low read speed, the provisional bit stream reading unit can cope with high-speed access. The buffer is pre-read as a provisional bit stream file, and when the pre-reading of an optimal amount is completed, the bit stream reading unit reads and transmits the provisional bit stream file in parallel with the pre-read operation, and processes the processed part. Can be erased. Thereby, the capacity required for the buffer can be reduced. Also, instead of waiting for the entire bit stream to be temporarily read ahead in the buffer and sending it to the bit stream processing unit as in the prior art, the transmission is performed in parallel with the pre-reading, so Waiting time can be reduced.

According to the video stream storage / reading device of the third aspect, the storage device according to the general file management system is used as a buffer, and the provisional bit stream storage unit allows provisional bit access to the buffer which can support high-speed access. In parallel with storing the stream file as a divided file, the bit stream storage unit reads the temporary bit stream file for each divided file and stores it in the low-speed storage device, and processes the temporary bit stream file. Can be deleted for each divided file. Thereby, the capacity required for the buffer can be reduced, and the processing time until the end of storing the bit stream can be reduced.

According to the fourth aspect of the present invention, a storage device according to a general file management system is used as a buffer, and a provisional bit stream reading unit uses a provisional bit stream reading unit to access provisional bits to a buffer that can support high-speed access. In parallel with storing the stream file as a divided file, the bit stream reading unit reads the provisional bit stream file for each divided file and sends it to the bit stream processing unit to process the provisional bit stream file. Can be deleted for each divided file.
This reduces the amount of buffer space required,
The entire processing time, in particular, the waiting time before reproduction by prefetching can be reduced.

According to the bit stream storing / reading device of the present invention, a storage device according to a FIFO compatible file management system capable of adding data to the end of the same file and deleting the head portion is used as a buffer. In parallel with storing the temporary bitstream file in a buffer that can support high-speed access by the FIFO-compatible temporary bitstream storage unit as a single file, the FIFO-compatible temporary bitstream storage unit The head of the provisional bit stream file is read and stored in a low-speed storage device, and the processed portion of the provisional bit stream file can be erased by rewriting the file management table and the area management table. By using a file management system compatible with FIFO, it is possible to reduce the overhead due to reading and writing of the storage device as compared with the case of creating a plurality of divided files, so that the processing time can be further reduced. .

According to the bit stream storing / reading device of the present invention, the storage device according to the FIFO compatible file management system capable of adding data to the end of the same file and deleting the head portion is used as a buffer. In parallel with storing the temporary bitstream file in a buffer that can support high-speed access as a single file by the FIFO-compatible temporary bitstream reading unit, the FIFO-compatible temporary bitstream reading unit The head of the provisional bit stream file is read and sent to the processing unit, and the processed part of the provisional bit stream file can be deleted by rewriting the file management table and the area management table. By using a file management system compatible with FIFO, it is possible to reduce the overhead due to reading and writing of the storage device as compared with the case of creating a plurality of divided files, so that the processing time can be further reduced. .

According to the bit stream storing / reading device of the present invention, a speed changing type bit stream storing unit having a different writing speed depending on the storage position is used as a low speed bit stream storing unit. Starting from the part with the slower writing speed of the speed change type bit stream storage unit, and gradually storing it in the part with the faster writing speed, it is possible to eliminate the writing time after capturing the video and shorten the processing time Then, the storage can be ended at the same time as the end of the video capture.

According to the bit stream storage / read device of claim 8, a speed change type bit stream storage unit having a different writing speed depending on the storage position is used as the low speed bit stream storage unit, and the speed change corresponding temporary bit stream read unit is used. By starting reading from the high-speed reading part of the speed-variable bit stream storage unit and gradually shifting to the low-speed reading part, it is possible to eliminate the pure waiting time before video playback, and reduce the processing time. The playback can be started immediately after shortening.

According to the ninth aspect, the storage unit used by the provisional bit stream storage unit and the storage unit used by the present bit stream storage unit are independently written while being switched by a switch. By performing reading and erasing, a first-in first-out (FIFO) operation of a temporary bitstream file can be realized more efficiently and with less overhead, and the processing time can be further reduced.

According to the bit stream storing / reading device of the tenth aspect, the storage unit used by the provisional bit stream reading unit and the storage unit used by the present bit stream reading unit are independently written while being switched by a switch. By performing reading and erasing, a first-in first-out (FIFO) operation of a temporary bitstream file can be realized more efficiently and with less overhead, and the processing time can be further reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a bitstream storage / readout device according to a first embodiment of the present invention.

FIG. 2 is a graph showing a change in the size of a provisional bit stream file created in a high-speed bit stream storage unit when a bit stream is stored in a bit stream storage and reading device.

FIG. 3 is a configuration diagram of a bit stream storage / read device according to a second embodiment of the present invention.

FIG. 4 is a graph showing a change in the size of a provisional bit stream file created in a high-speed bit stream storage unit when a bit stream is stored in a bit stream storage and reading device.

FIG. 5 is a diagram for explaining a file management system in a high-speed bit stream storage unit of the device according to the third and fourth embodiments of the present invention.

FIG. 6 is a diagram for explaining an operation of a file management system in a high-speed bit stream storage unit of the device according to the third and fourth embodiments of the present invention.

FIG. 7 is a configuration diagram of a bitstream storage / readout device according to a third embodiment of the present invention.

FIG. 8 is a configuration diagram of a bit stream storage / read device according to a fourth embodiment of the present invention.

FIG. 9 is an explanatory diagram of a speed-variable bit stream storage unit of the bit stream storage / read device according to the fifth and sixth embodiments.

FIG. 10 is a graph of a change in file size for explaining the operation and effect of the bit stream storage / read device according to the fifth embodiment of the present invention.

FIG. 11 is a view for explaining an effect of the fifth embodiment of the present invention and for explaining a case not according to the fifth embodiment;
Graph of changes in file size.

FIG. 12 is a graph of a change in file size for explaining the operation and effect of the bit stream storage / read device according to the sixth embodiment of the present invention.

FIG. 13 is a view for explaining an effect of the sixth embodiment of the present invention and for explaining a case not according to the fifth embodiment;
Graph of changes in file size.

FIG. 14 is a configuration diagram of a bit stream storage / read device according to a fifth embodiment of the present invention.

FIG. 15 is a configuration diagram of a bitstream storage / readout device according to a sixth embodiment of the present invention.

FIG. 16 is a configuration diagram of a bit stream storage / read device according to a seventh embodiment of the present invention.

FIG. 17 is a configuration diagram of a bit stream storage / read device according to an eighth embodiment of the present invention.

FIG. 18 is a diagram showing a configuration of a bitstream storage / readout device (storage) according to a conventional technique.

FIG. 19 is a diagram showing a configuration of a bit stream storage / read device (read) according to a conventional technique.

[Explanation of symbols]

101, 1801 Video camera 102, 1605, 1802 Bit stream generation unit 103, 303, 1601, 1701 High speed bit stream storage unit 1803, 1903 High speed bit stream storage unit 104, 304, 1705 Low speed bit stream storage unit 1804, 1904 Low speed bit stream Storage unit 105, 1604 Temporary bit stream storage unit 106, 306, 706, 806 Temporary bit stream file 107, 1606 Main bit stream storage unit 108, 308 Bit stream file 1804, 1806, 1904, 1906 Bit stream file 301, 1901 Monitor 302 , 1707, 1902 Bit stream processing units 305, 1706 The present bit stream reading units 307, 1704 Bit stream reading unit 703 FIFO-compatible high-speed bit stream storage unit 705 FIFO-compatible temporary bit stream storage unit 707 FIFO-compatible main bit stream storage unit 803 FIFO-compatible high-speed bit stream storage unit 805 FIFO-compatible main bit stream reading unit 807 FIFO-compatible provisional bit stream reading unit 901 Speed change type bit stream storage unit 1407 Speed change correspondence type bit stream storage unit 1507 Speed change correspondence type temporary bit stream reading unit 1602, 1702 Disk 1603, 1703 Head

Claims (10)

[Claims] 1. An apparatus for storing and reading a bit stream as continuous bit information, comprising: a bit stream generator for generating a bit stream by digitization; and a speed lower than a speed at which the bit stream generator generates the bit stream. A low-speed bit stream storage unit for storing the bit stream; a high-speed bit stream storage unit for storing the bit stream at a speed higher than the bit stream generation unit generates the bit stream; and a bit stream generated by the bit stream generation unit Is read from the provisional bit stream storage unit in the high-speed bit stream storage unit, and the head of the bit stream stored in the high-speed bit stream storage unit by the provisional bit stream storage unit. A low-speed bit stream storage unit, and a bit stream storage unit that deletes the bit stream that has been stored in the low-speed bit stream storage unit from the high-speed bit stream storage unit. Bit stream storage and reading device. 2. An apparatus for storing and reading a bit stream as continuous bit information, comprising: a bit stream processing unit for converting a bit stream as digital information; A low-speed bit stream storage unit whose read speed is lower than the speed at which the bit stream processing unit processes the bit stream; a bit stream is stored; and when the stored bit stream is read, the read speed is set by the bit stream processing unit. A high-speed bit stream storage unit that is faster than the stream processing speed; a provisional bit stream read unit that reads a bit stream from the low-speed bit stream storage unit and stores the bit stream in the high-speed bit stream storage unit The speed obtained by multiplying the speed of the difference between the bit stream speed required by the bit stream processing unit and the read speed of the low-speed bit stream storage unit by the overall time of the process performed by the bit stream processing unit is obtained. When the high-speed bit stream storage unit stores the bit stream of the optimum pre-read amount as the optimum pre-read amount, the bit stream is read from the high-speed bit stream storage unit and input to the bit stream processing unit. A bit stream reading unit that deletes a bit stream that has been input to the bit stream processing unit from the high-speed bit stream storage unit. 3. The bit stream storage and reading device according to claim 1, wherein the high-speed bit stream storage unit manages stored data as a file, and the file management system includes a file management table and a file management table. To manage a file based on the file name that specifies the file by managing the file by using the area management table, first, the file name and the area head indicating the head of the area management table for the area where the file data is stored By referring to the file management table that enables reference of the area management table using the pointer, and then referring to the area management table that manages the area in the storage unit where the data of the same file is stored, the data of the file can be referred to. To know the area in the storage unit where The provisional bit stream storage unit divides the bit stream generated by the bit stream generation unit into a predetermined size and stores the divided bit stream as a plurality of files in the high-speed bit stream storage unit. The bit stream storage unit reads the bit stream stored as a file by the provisional bit stream storage unit from the high-speed bit stream storage unit for each file, stores the read bit stream in the low-speed bit stream storage unit, and A bitstream storage / readout device for deleting from a bitstream storage unit. 4. The bit stream storage and reading device according to claim 2, wherein the high-speed bit stream storage unit manages stored data as a file, and the file management system includes a file management table and a file management table. To manage a file based on the file name that specifies the file by managing the file by using the area management table, first, the file name and the area head indicating the head of the area management table for the area where the file data is stored By referring to the file management table that enables reference of the area management table using the pointer, and then referring to the area management table that manages the area in the storage unit where the data of the same file is stored, the data of the file can be referred to. To know the area in the storage unit where The provisional bit stream reading unit divides the bit stream read from the low-speed bit stream storage unit into a predetermined size and stores the divided bit stream as a plurality of files in the high-speed bit stream storage unit. The bit stream reading unit reads the bit stream stored as a file by the provisional bit stream reading unit from the high-speed bit stream storage unit for each file, stores the bit stream in the low-speed bit stream storage unit, and A bitstream storage / readout device for deleting from a high-speed bitstream storage unit. 5. The bit stream storage / read device according to claim 3, wherein the high-speed bit stream storage unit is capable of rewriting a file management table and an area management table for a part of a file in the file management system. A FIFO-compatible high-speed bit stream storage unit, wherein the temporary bit stream storage unit stores the bit stream generated by the bit stream generation unit as a file in the high-speed bit stream storage unit.
A corresponding provisional bitstream storage unit, wherein the present bitstream storage unit reads the head of the file stored in the high-speed bitstream storage unit by the FIFO-compatible provisional bitstream storage unit, and Stored in the stream storage unit,
And a FIFO-compatible main bit stream storage for deleting information of an area used by the head of the file from the area management table and changing an area head pointer of the file information of the file in the file management table to a new position. And a bit stream storage and reading device. 6. The bit stream storage / read device according to claim 4, wherein the high-speed bit stream storage unit is capable of rewriting a file management table and an area management table for a part of a file in the file management system. A FIFO-compatible high-speed bit stream storage unit, wherein the temporary bit stream storage unit stores the bit stream generated by the bit stream generation unit as a file in the high-speed bit stream storage unit.
A compliant provisional bit stream storage unit, wherein said provisional bit stream case readout is a FIFO compliant provisional bit stream reading unit for storing the bit stream read from said low speed bit stream storage unit as a file in said high speed bit stream storage unit The bit stream storage unit reads the head of the file stored in the high-speed bit stream storage unit by the FIFO-compatible temporary bit stream reading unit, and inputs this to the bit stream processing unit. Deletes the information of the area used by the head of the file from the area management table and changes the area head pointer of the file information of the file included in the file management table to a new position.
A bitstream storage / readout device, which is an O-compatible main bitstream reading unit. 7. The bit stream storage and reading device according to claim 1, wherein the low-speed bit stream storage unit has a storage speed that differs depending on a storage position in the storage unit.
The storage speed is higher than the speed at which the bit stream generation unit generates the bit stream at the highest position,
In the position of the lowest speed, the bit stream generation unit is a speed change type bit stream storage unit having a characteristic that it is smaller than the speed at which the bit stream is generated. The bit stream stored in the stream storage unit is read out, the bit stream is stored first from the portion where the storage speed of the speed-change type bit stream storage unit is low, and the storage in the speed-change type bit stream storage unit is completed. A bitstream storage / readout device, which is a speed change-compatible main bitstream storage unit for deleting a bitstream from the high-speed bitstream storage unit. 8. The bit stream storage and reading device according to claim 2, wherein the low-speed bit stream storage unit has a different read speed depending on a storage position in the storage unit, and the read speed is the bit stream processing at the highest speed position. A speed change type bit stream storage unit characterized in that the speed of the bit stream processing unit is higher than the speed at which the bit stream is processed, and at the lowest speed, the speed is lower than the speed at which the bit stream processing unit processes the bit stream. However, the speed-change-type bit stream storage unit is a speed-change provisional bit stream read unit that reads a bit stream first from a portion where the read speed is high and stores the bit stream in a high-speed bit stream storage unit. Bit stream storage read Out equipment. 9. The bitstream storage / readout device according to claim 1, further comprising two or more high-speed bitstream storage units, wherein at least one high-speed bitstream storage unit stores a bitstream and at least one high-speed bitstream. A bit stream storing and reading device, wherein reading and deleting of a bit stream in a stream storage unit operate simultaneously. 10. The bitstream storage / readout device according to claim 2, further comprising two or more high-speed bitstream storage units, wherein at least one high-speed bitstream storage unit stores a bitstream and at least one high-speed bitstream. A bit stream storing and reading device, wherein reading and deleting of a bit stream in a stream storage unit operate simultaneously.