MXPA01002575A

MXPA01002575A - Device for scanning an information carrier, method of manufacturing, and information carrier

Info

Publication number: MXPA01002575A
Application number: MXPA/A/2001/002575A
Authority: MX
Inventors: Stek Aalbert; Van Woudenberg Roel
Original assignee: Koninklijke Philips Electronics Nv
Priority date: 1999-07-13
Filing date: 2001-03-12
Publication date: 2001-11-21

Abstract

A device for reading an information carrier (1), which information carrier carries identification information (10, 11) and user information (7, 8), which identification information (10, 11) is arranged so as to be spread over the information carrier and which information comprises data (7, 13) and parities (8, 12). The device includes read means (42, 34) for reading the information from the information carrier and error correction means (45) for correcting errors in the information. The device further includes organization means (46) for organizing the information in such a way that both the identification information and the user information can be processed by the error correction means (45). The invention further relates to a method of manufacturing and to an information carrier (1).

Description

DEVICE FOR SCANNING AN INFORMATION CARRIER (CARRIER), MANUFACTURING METHOD AND INFORMATION CARRIER.

The invention relates to a device for scanning an information carrier, said information carrier carries identification information and user information, the identification information is spread on the carrier of information and on the information that includes data and parities, said device includes reading means for reading the information present in the information carrier, in the device including means of correcting errors for the correction of errors in the information. The invention also relates to a method of manufacturing an information carrier, the method comprising the following steps: a. Receipt identification information, b. Calculation parities based on identification information, c. Add the parities to the identification information, d. Printing of identification information and parities, e. Proportion to the infomercing carrier with the identification information and parities. The invention also relates to an information carrier that carries identification information, the identification information is placed so that it is spread on the information carrier.

A device of the type defined in the opening paragraph is known, inter alia from US 4, 364,181. Said document describes an apparatus for processing information in the form of a digital video signal. The signal is composed of real video signals and identification signals. The identification signals may for example spy the track number, the structure number, the field number or the line number of the video signal.

Video signals and identification signals can be generated, for example, by reading an information carrier, for example a rewritable information carrier, such as a CD-RW information carrier, a DVD-RW, or a DVR. In the following, the information corresponding to the video signals in said information carrier will be referred to as user information and the information corresponding to the identification signals in said information carrier will be referred to as identification information. This identification information may include address information as well as disk information, both stored for example in address information areas. In the video signal chaos, this address information can for example spy the position of the video information in each field. The disk information can be related to a variety of information carrier parameters. Both the identification information and the user information must be protected from, for example, rips and presence of dirt in the information carrier. For this purpose, parities are added to the information. These errors can be corrected through these parities. Since the invention is related to the error correction processes as such and since the correction of errors by the addition of parities is generally known to those skilled in the art, reference is made to US 4,413,340 (PHQ 80.009) for an example of an error correction process. This document describes the process used to correct errors in the Digital Audio Compact Disc. As described earlier in this document, a rewritable information carrier carries a plurality of different types of data, for example, identification information and user information. Parities are added to each type of data with «< , -feg &? «A. the purpose of allowing the correction of errors. This correction is an intensive and costly computing operation as far as the IC area is concerned.

It is an object of the invention to realize a device in which the errors of an information carrier can be scanned and corrected in an efficient manner by means of an error correction code.

In this regard, according to the invention, a device for scanning an information carrier of the type defined in the opening paragraph is characterized in that the device also includes means for organizing information in such a way that both the identification information and the user information can be processed by means of error correction. Through the organization of information it is possible to use the same hardware for the correction of errors present in the different types of information. This simplifies the device because only one type of error correction means has to be included, which has a positive effect on the production cost of the device. The invention is based inter alia on the recognition of the fact that, although different types of data have different formats, the same error correction means can be used for the correction of errors present in the data by means of the organization of these different types of data, which in fact refer to the fact that the identification information blocks and the user information blocks of the same magnitude are generated, said identification of information consists of relatively small items of information that, by their nature, they are stored in such a way that they are spread on the information carrier.

According to a second aspect of the invention, a device of the type defined in the opening paragraph is characterized, according to the invention, in which the identification information comprises permanent information and in which the user information comprises rewritable information. The permanent information is, for example, information already present in a rewritable optical information carrier, such as a CD-RW information carrier, a DVD-RW or a DVR. This information may include, for example, address information and disk parameters. The rewritable information is, for example, the one that could be stored in these optical information carriers rewritable by the terminal user. According to another aspect of the invention, a device of the type defined in the opening paragraph is characterized, according to the invention, in that the permanent information comprises address information and disk information. In said address information the permanent information may include address information and disk information. The address information then comprises, for example, information on the track numbers and sector numbers. The disk information then comprises a greater number of information carrier parameters. According to another aspect of the invention, a device of the type defined in the opening paragraph is characterized, according to the invention, in that the organization means further include addition means for adding test bytes of predetermined value to the information of ID. This device has the advantage that it is almost always possible to provide different types of data of adequate format in an efficient manner so as to allow faster error correction to be achieved. This can be useful in case the magnitude of a block of identification information is not a sub-multiple of the magnitude of a block of user information. At the moment that a given type of data can not be provided in the desired format with only the rewritable information and the permanent information, the test bytes are added in order to obtain that desired format. Since said addition of the test bytes is made in the device to scan the information carrier, this addition does not result in a lower data capacity (ie, the capacity for rewritable information) in the information carrier. In order to allow data to be properly corrected with the help of error correction means, it is obvious that during the computation of the parities associated with the data (this is done before the data is written in the information carrier) the value of these test bytes must be known in order to allow the correct parities to be computed . This will be evident to experts in the art of error correction techniques. Only in this way is it possible to calculate the parities that make possible the correction of errors after reading and demodulation of the data. Another characterization is characterized in that the device also includes writing methods. By including in the device, in addition to the reading means, writing means for the formation of optically readable marks on a recordable type information carrier, the device can perform reading functions as well as recording functions. Another characterization is characterized in that the organization means are also adapted to collect the identification information by reading the address information areas of a predetermined number of tracks and subsequently by organizing the address information already read.

• + .. • -. »- * •" "" • »» - -? Ai? Another characterization is characterized in that the predetermined number of tracks is two, each track includes eight areas of address information, each area of address information comprises 15 bytes of address information, and in which addition means are adapted to add eight non-zero value test bytes to the identification information, in particular the FF value in hexadecimal notation. The default of the test bytes is not arbitrary: By providing the test bytes with a non-zero value (in this case the FF value in hexadecimal annotation) it is prevented that the parities to be calculated assume the value zero in the case that the Disk Information is composed of only zeros. Certainly, in the case that the test bytes and disk information are composed of only zeros, it will be the result that when the parities are calculated, all they will have a value of zero The invention also relates to a manufacturing method, characterized in that the identification information is placed so that it is spread on the information carrier. The invention also relates to an information carrier characterized in that the identification information comprises parities calculated on the basis of the identification information. These as well as later aspects of the invention will become apparent and will be elucidated by the following description of the characterizations with respect to the accompanying drawings, in which Figure 1 shows in diagram form a carrier of rewritable information, Figure 2 shows an example of the structure of a data block with rewritable data parities in an information carrier called DVR, Figure 3 shows an example of the structure of a header block in a DVR information cap, Figure 4 shows way to diagram a device to scan an information carrier, and Figure 5 shows an example of the means of organization. Similar elements in different Figures maintain identical reference numbers.

Figure 1 shows a rewritable information carrier 1 in the form of a diagram, in this case a cap of DVR information. The invention is not limited to a DVR information carrier but can also be applied to any information carrier such as a CD-RW or a DVD-RW. The information carrier 1 has a recording area 2 having a diameter 3 and an external diameter 4. The recording is 2 consists of tracks (not shown in Figure 1), in the present case with a recording of ground / slots, which are intercepted by address information areas 5. The start points of the address information areas are aligned radially along the radial lines 6. This deployment of the information carrier serves to illustrate the invention. As stated, the address information areas comprise information that relates to a multitude of information carrier parameters. As examples, the following disk parameters are mentioned: disk category, version number, disk size, maximum transfer average, number of recording layers, type of recording layer (for example rewritable) and recording speed.

Figure 2 shows an example of the structure of a data block with rewritable data parities in an information carrier called DVR. The data block 7 comprises 216 bytes of data, the data in the data block are protected by the Solomon Reed Code having 32 parities 8. The total length is therefore 248 bytes or 248 symbols. In this case, a symbol has a size of one byte. This data block is obtained by reading the rewritable information in the DVR information carrier. In the present case, the size of a block is 248 bytes. Figure 3 shows an example of the structure of a header block in a DVR information carrier. In the present example, the header block comprises disk information (see 51 in Figure 5). In this chaos, the header block does not include address information (see 50 in Figure 5). As a result of this, each generated header block is identical. Each address information area 5 of Figure 1 includes a header with 15 bytes of Disk information, one revolution includes 8 headers that have 120 bytes in total. The first Disk Information Block 10 is obtained by reading the 8 headers in one revolution and combining them. The second Disk Information Block 11 is obtained by reading the 8 headers in the next revolution and combining them. This second Disk Information block 11 includes the 32 bytes of parities 12. As a result, the data 13 comprises the first Disk Information block 10 and the greater part of the second Disk Information block 11. In order to allow the two Disk Information blocks comprise 240 bytes in total with the same error correction code, the first 8 bytes, represented by the test block 9, are added by defining them in FF in hexadecimal notation in the decoder (or in the means of organization 46, see Figure 4). This means that these bytes are not on the disk. In this way, both the header information and the rewritable information can be corrected using the same hardware. Therefore, the total header block, just like the data block, comprises 120 + 120 + 8 = 248 bytes. This standard header block is referred to as a structure. As stated, the header blocks include a multitude of disk parameters. Since these parameters are related to the same information carrier, each header block has the same content. In the present example, the header block is generated by reading two tracks of successive slots or two successive ground tracks with the address information areas. These address information areas can be provided throughout the information carrier, but their presence can also be restricted to the entry guide zone end and / or exit guidance zone. It will be evident that both Figures 2 and 3 show the logical structures of the 'data and header blocks and not their physical structures since, for example, the Disk information is present in the headings scattered in the information carrier. Figure 4 shows in diagram form a device for scanning an information carrier, for example the information carrier DVR as shown in Figure 1. The device has drive means 26 for rotating the information cap 1 and a head of information. reading 27 to read the clues in the information carrier. The reading head 27 comprises an optical system of a known type intended to generate a point of light 28 focused on a track of the information cap by means of a light beam 29 guided by optical elements such as a collimator lens 39, to collimate the beam of light, and a lens of objective 40, to focus the beam of light. This light beam 29 is produced by a radiation source 41, for example an infrared laser diode having a wavelength of 780 nm and an optical power of 3 mW. The read head 27 further includes an actuator adapted to focus the light beam 29 on the information carrier and a track actuator 30 for the careful placement of the light spot 28 in a radial direction in the center of the track. In addition, tracking the track with the laser beam can also be achieved by varying the position of the objective lens 40. After the light beam 29 is reflected from the information carrier, it is detected by a detector 42 of a known type, for example a dial detector, which generates detector signals 31 including a read signal, a track error signal, a focus error signal, a synchronization signal and a blocking signal. For this purpose, one can make use of, for example, a beam division cube 43, a cube of polarizing beam split, a film or a retarder. The device includes track means 32 coupled to the read head 27 for receiving the track error signal from the read head 27 and for controlling the track actuator 30. During reading the reading means 34 receives the read signal . The read signal 44 is therefore transferred and received by the means of organization 46. In these means of organization 46 the reading signal is demodulated. The demodulation method obviously depends on the method by which the data has been modulated (for a more detailed description of this process reference is made to the example shown in Figure 5). It is possible that the rewritable information has been modulated other than the permanent information present in the headings, that is, the information rewritable for example with a so-called RLL code (1,7) and the permanent information for example with an RLL code (2,7). The device further includes an address detector 35, for detecting addresses and Disk Information in the header fields, and positioning means 36 for the sturdy placement of the read head 27 in a radial direction of the track. Based on the signals 47 obtained from the address detector 35 the organization means 46 can generate «# A &a * ..,. A_M. the data blocks and the header blocks as shown in Figure 2 and Figure 3 and can supply these blocks to the error correction means 45, thereby enabling both the permanent information and the rewritable information present in the carrier of DVR information to be corrected by the same error correction means 45. For the purpose of enabling the data blocks and header blocks to be generated from the demodulated read signal, the organization means must be stored in the bytes of Information of disc of two revolutions and must combine them with 8 bytes of test to form a block of header (or block of information of disc) of 248 bytes. Said addition of the test bytes is effected by means of addition. These means of addition are part of the organization means 46. Pro therefore, the test bytes are added to the header block after the demodulation of the read signal. After correction in the error correction means 45, the demodulated signal corrected for errors 48 is available in the production for further processing. The device further includes a system control unit 37 adapted to receive commands from a control or user computing system and to control the device via control lines 38, for example a system bus connected to the driving means 26. , the positioning means 36, the address detector 35, the track means 32 and the reading means 34. For this purpose, the system control unit 37 includes a control circuit for example a microprocessor, a program memory and control doors to carry out the processes as described hereinafter. The system control unit 37 can also be implemented in a state machine in logic circuits. In another characterization the device may include, in addition to the reading means 34, writing means for forming optically readable marks on an information carrier of a recordable type, which allows the device to perform both read and write functions. Figure 5 shows an example of the means of organization. As stated, the organizing means 46 ensures that several ECC blocks are generated, that is, the header blocks and the data blocks. In Figure 5 this is illustrated for the generation of the header blocks. The read signal 44 and the signal 47 of the address detector 35 are applied to the demodulator 49 for the demodulation control. The demodulator demodulates the read signal 44 and divides the demodulated read signal into an address data component 50 and a Disc Information component 51. The address data serves as a so-called pointer 53 for storing the Disk Information in the correct location in the memory 52. Among other things, the address data includes the track number and the segment number. Based on this information it is possible to calculate in which position the Disc Information is stored (for example that the Disc Information of each even track number and segment 0 is stored in the first position of the memory 52). The signal 47 of the address detector 35 is added to the address data component 50 and the Disk Information component 51 for the purpose of controlling the division of the demodulated read signal. The Disk Information in the Disk Information component is then loaded into the memory 52. Once all the memory has been loaded with the Disk Information (and the test bytes 9) this information can be applied to the media. error correction 45. Likewise, the data blocks associated with the rewritable information can be generated and provided to the same error correction means 45. Although the invention has been described with reference to the characterizations mentioned above, it is obvious that Alternative characterizations can be used with the object - J ** "M ^ - to .-« - to achieve the same goal For example, the invention is not at all limited to the present example of data blocks and 248 byte header. In addition, any arbitrary number of test bytes can be added to the rewritable information and / or permanent information.Furthermore, the invention is not limited to the error correction processes where each symbol It has one byte size The error correction process to be used by the present invention is not limited to the error correction method as described in US 4,413,340, alternatively, other known error correction processes can be used. as the product code or picket code picket.In addition, it is assumed that the invention resides in any of the novel features and / or combination of features. ^^^^^^^^^^^ a ^^^^^^^^^^ UtB ^^^^^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^

Claims

CHAPTER CLAIMING Having described the invention, it is considered as a novelty and, therefore, the content is claimed in the following:

CLAIMS 1. A device for scanning an information carrier (1), said information carrier carries identification information (10, 11) and user information (7,8), the identification information (10,11) is displayed in the information carrier and in the information including the data (7,13) and parities, (8,12), said device includes reading means (42, 34) to read the information present in the information cap, the device that includes error correction means (45) for correcting errors in the information, characterized in that the device also includes organization means (46) for the organization of the information in such a way that the identification information and the user information they can be processed by the error correction means (45).
2. A device as claimed in Claim 1, characterized in that the identification information (10, 11) comprises permanent information (10,11) and that the user information (7,8) comprises rewritable information (7,8) .
3. A device as claimed in Claim 2, characterized in that the permanent information (10, 11) comprises address information (50) and disk information (51).
4. A device as claimed in Claim 1, characterized in that the organizing means (46) further include addition means (46) for adding test bytes (9) of predetermined value for the identification information (10, 11).
5. A device as claimed in Claim 1, characterized in that the device further induces writing means.
6. A device as claimed in Claim 1, wherein the information carrier (1) has a pattern of substantially parallel tracks, the tracks comprising address information areas (5) and data areas (2), the information areas of addresses (5) include the identification information, characterized in that the organization means (46) are further adapted to collect the identification information (10, 11) by reading the address information areas (5) of a predetermined number of tracks and later when organizing the address information already read.
7. A device as claimed in Claim 6, characterized in that the predetermined number of tracks is two, each track includes eight address information areas (5), each address information area comprises 15 bytes of address information, and in that the addition means (46) are adapted to add eight test bytes (9) of non-zero value to the identification information (10, 11), n particular the FF value in hexadecimal annotation.
8. A method of manufacturing an information cap (1), the method comprises the following steps: to. reception of identification information (10, 11), b. parity calculation (12) based on the identification information (10, 11), c. adding parities (12) to the identification information (10, 11), d. production of identification information (10, 11) and parities (12), e. proportion of the information carrier (1) with the identification information (10, 11) and parities (12), characterized in that the identification information (10, 11) is placed so that it is spread on the carrier of information (1) ).
9. A method of manufacturing an information carrier (1), the method comprises the following steps: a. reception of identification information (10, 11), b. reception of test bytes (9) of predetermined value, c. calculation of parities (12) based on the identification information (10, 11) and test bytes (9), d. adding parities (12) to the identification information (10, 11), e. production of identification information (10, 11) and parities (12), f. proportion of the information carrier (1) with the identification information (10, 11) and parities (12), characterized in that the identification information (10, 11) is placed so that it is spread on the infomercing carrier (1) ).
10. A method as claimed in claim 9, characterized in that the test bytes (9) have a non-zero value, in particular the value FF in hexadecimal notation. An information carrier that carries identification information (10, 11), the identification information (10, 11) being placed in a manner that is spread on the information carrier (1), characterized in that the identification information (10 and 11) comprises parities (12) calculated based on the identification information (10, 11, 13).