Abstract: Secure erase of files and unallocated sectors on storage media such that any previous data is non-recoverable. The database contains sets of data patterns used to overwrite the data on different physical media. The software programs manage the overwriting process automatically when a file has been deleted. When de-allocated sectors in the file system are pruned from a file or escaped the file deletion process also finds them. Data will never be found on deleted sectors or on pruned sectors is overwritten.

Abstract: Techniques for processing tape storage include determining a current position of a read device to read a data block from a tape storage medium having a plurality of duplicate data areas, receiving a request to read a data block from the tape storage medium, and reading the requested data block from a duplicate data area from among the plurality of duplicate data areas that is nearest the current position of the read device.

Abstract: In some implementations, a recording medium includes a plurality of data areas, a plurality of data area separating sections, and one or more blank zones. Each data area is configured to store data. Each data area separating section is disposed between the data areas and extends in parallel with respect to the data areas. Each data area separating section is configured to prevent data from being written into the data area separating section. Each blank zone extends in a direction perpendicular to the data areas and is configured to record written data.

Abstract: Systems and methods for performing refresh operations using write/read commands are provided. In one embodiment, a disk drive comprises a disk partitioned into a plurality of refresh zones, a head configured to write data to and read data from the disk, and a controller. The controller is configured to receive an access command, to read data from at least one of the refresh zones using the head in response to the access command, to check a condition of the read data, and to determine whether to refresh the at least one refresh zone based on the condition of the read data, wherein the read data includes data from a portion of the at least one refresh zone not being accessed by the access command.

Abstract: Systems and methods for writing data to a disk under write disturbance conditions are provided. In one embodiment, a disk drive comprises a disk and a detection system configured to detect a write disturbance condition. The disk drive further comprises a controller configured to alternately operate in a normal mode and a write disturbance mode, wherein, the controller is configured to write data to data tracks on the disk in the normal mode and to write data to data tracks on the disk that are spaced farther apart in the write disturbance mode, and the controller is configured to switch from the normal mode to the write disturbance mode when the detection system detects the write disturbance condition.

Abstract: In an implementation, a media drive comprises bit patterned magnetic media and one or more modules. The one or more modules are to cause data to be written on the bit patterned magnetic media in a data sector that includes a synchronization mark disposed between data blocks of the data sector.

Abstract: A method for recovering data from a failed tape cartridge is presented. The reliability of a tape cartridge is assessed via the number of read errors encountered. If the number or read errors is excessive, the tape cartridge is deemed unreliable and the tape cartridge is restricted from storing anymore data. A search is performed to look for duplicate data and if found a copy of the duplicate data is stored to a replacement tape cartridge. The replacement tape cartridge assumes all identity of the original failed tape cartridge.

Abstract: Various embodiments of the present invention provide systems and methods for data processing. As an example, a data processing circuit is disclosed that includes a codeword detector circuit operable to apply a codeword based data detection algorithm to a data input corresponding to an encoded servo data region to yield a detected output, and a servo address mark processing circuit operable to identify a pre-defined pattern in the detected output.

Abstract: According to one embodiment, a servo area of a magnetic recording medium includes magnetic dots arrayed at a period L0. The magnetic dots include a plurality of magnetic dot regions divided in the cross track direction. A width Wm in the down track direction of the mth magnetic dot region from the innermost circumference and a number Nm of dot rows in the down track direction of the mth region meet a relationship represented by L0{Nm?3/2?0.3}?Wm?L0{Nm?3/2+0.3}??(1).

Abstract: According to one embodiment, a magnetic recording apparatus includes a magnetic recording medium for perpendicular magnetic recording system, a magnetic head including a read head to read data from the magnetic recording medium, and an actuator to actuate the magnetic head on the magnetic recording medium. The magnetic recording medium includes a first magnetic pattern recorded in a servo area by applying a magnetic field horizontally to a disk surface, and the first magnetic pattern corresponding to positioning data used for positioning the magnetic head. The magnetic recording medium further includes a second magnetic pattern recorded in the servo area by applying a magnetic field perpendicularly to the disk surface, and the second magnetic pattern corresponding to position correction data used for correcting the positioning data. The position correction data is derived from modulated original position correction data. The original position correction data is created for correcting the positioning data.

Abstract: According to one embodiment, a magnetic recording device based on shingled-write recording method comprises a magnetic storage medium, a recording head, and an actuator. The magnetic storage medium comprises dot rows wherein a phase shift is between adjacent rows. The recording head covers a predetermined number of dot rows of the magnetic storage medium and comprises an edge at one of the dot rows. The actuator configured to move a recording head by an amount equivalent to a dot row after recording is performed on one of the dot rows by the recording head.

Abstract: According to one embodiment, a disk drive having a magnetic disk of the bit pattern media type is provided. The disk drive has a reproduction module configured to reproduce a signal from a measurement area provided on the magnetic disk and holding groups of phase-shift measuring bits, a measurement module configured to measure a phase shift that a write clock signal has with respect to data recording bits held in a data record area provided on the magnetic disk, when the signal reproduced by the reproduction module is indefinite, and a recording module configured to record data that corresponds to the data recording bits, by using the write clock signal adjusted by the phase shift.

Abstract: A method of reproducing data from a recording medium, each of the data including reference time information indicating a reference time and including packet data, the method including: reproducing the data from the recording medium; obtaining a difference between respective reference times indicated by the reference time information of the reproduced adjacent data; rearranging the data on a time axis such that a time interval between adjacent data is equal to the obtained reference time difference; and outputting the rearranged data.

Abstract: In a disk storage system, the disk may include a full null servo position error signal (“PES”) wedge, followed by a data wedge, and then a short null servo PES wedge. To improve the accuracy with which information read from the short null servo PES wedge can be used to help keep the read head centered over the information track being read, the short null servo PES wedge may include a calibration field. Information read from the calibration field can be used to compensate the subsequently read PES information in the short wedge for possible sampling phase error that may have accumulated since the full null servo PES wedge was read. This type of short null servo PES wedge also has other possible uses.

Abstract: A method and system for tracking a sequence of bad blocks in a RAID system by storing the logical block address of the first bad block and the number of bad blocks in the sequence is disclosed. The method and system may also track multiple sequences of bad blocks by storing a memory pointer to the next sequence in each previous sequence in an expandable linked list configuration.

Abstract: According to one embodiment, there is provided a magnetic disk apparatus having a magnetic disk having magnetic dot lines each including magnetic dots arrayed at equal intervals in a down track direction, and a read/write head which uses a plurality of adjacent magnetic dot lines as one track and sequentially performs read and write on the magnetic dots included in the magnetic dot lines constituting the track, in which the magnetic dots included in each of the magnetic dot lines in each track of the magnetic disk are displaced in the down track direction from the magnetic dots included in the adjacent dot line in the track depending on a possible skew angle between the read/write head and the track so that the magnetic dots are sequentially accessed by the read/write head.

Abstract: For determining an access sequence of a plurality of data groups stored on a tape medium, a first data group in the access sequence is selected based on which data group in the plurality of data groups has a beginning closest to a current position of the tape medium. A second data group in the access sequence is selected based on which remaining data group in the plurality of data groups has a beginning closest to an end of the first data group in the access sequence.

Abstract: A storage medium reproducing apparatus includes a storage unit, a correction history storage unit, a correction history implementing unit, and a correcting unit. The storage unit includes a plurality of information storage units storing information depending on whether a charge quantity is greater than a predetermined charge quantity threshold value, and a correction code storage unit storing error correction codes for the information stored in the information storage units. The correction history storage unit stores a correction history containing identification information for the information storage unit corrected with an error correction code is performed, and a content of the correction. The correction history implementing unit corrects information in compliance with the content of the correction when the information is read from the information storage unit.

Abstract: Systems and methods for detecting and designing enhanced disk sync marks using correlation detection are disclosed. The enhanced sync marks provide better noise immunity and higher detection rates over traditional Viterbi-based detection schemes even with a shorter sync mark length. The disk sync mark may provide optimal noise immunity for a particular target polynomial or a plurality of common target polynomials. The minimum Euclidean distance between a candidate sync mark and a plurality of right-shifted versions of the candidate sync mark is computed and compared with other candidate sync marks. The sync mark with the largest minimum Euclidean distance is then selected as the optimal mark. Systems and methods are also disclosed for detecting and designing a disk sync mark using correlation detection when the polarity of the disk is unknown or time-varying.

Abstract: A control module for a rotating storage medium. The control module includes: a memory, a buffer control module, and a disk formatter module. The memory is configured to store a data wedge format table including a plurality of entries. The buffer control module is configured to maintain a queue, wherein each of a plurality of entries of the queue is based on a corresponding one of the plurality of entries of the data wedge format table, and wherein each of the plurality of entries of the queue includes a servo number. The disk formatter module is configured to compare the servo numbers of the plurality of entries of the queue to present servo information, wherein the present servo information is based on a present position of a read/write device in relation to the rotating storage medium.

Abstract: Various embodiments of the present invention provide systems and methods for data processing. As an example, a data processing circuit is disclosed that includes a read circuit and a combining circuit. The read circuit is operable to provide a first instance of a user data set, a second instance of the user data set, and a third instance of the user data set. The combining circuit is operable to: combine at least a first segment of the first instance of the user data set with a first segment of the second instance of the user data set to yield a first combined data segment; provide a second combined data set that includes a combination of one or more second segments from the second instance of the user data set and the third instance of the user data set; and provide an aggregate data set including at least the first combined data set and the second combined data set. The second combined data set does not incorporate a second segment of the first instance of the user data set.

Abstract: An apparatus includes a recording media including a substrate, a plurality of tracks of magnetic material on the substrate, and a non-magnetic material between the tracks; a recording head having an air bearing surface positioned adjacent to the recording media, and including a magnetic pole, an optical transducer, and a near-field transducer, wherein the near-field transducer directs electromagnetic radiation onto tracks to heat portions of the tracks and a magnetic field from the magnetic pole is used to create magnetic transitions in the heated portions of the tracks; and a plasmonic material positioned adjacent to the magnetic material to increase coupling between the electromagnetic radiation and the magnetic material.

Abstract: This invention provides a technique of easily encoding image data to generate encoded data having high image quality within a target code amount using a small memory capacity by image encoding processing of performing frequency transform and quantization of each pixel block. A frequency transform unit separates image data into low frequency band data and high frequency band data. A coefficient quantizing unit, coefficient encoder, and code amount controller operate to encode the high frequency band data within a predetermined amount. When the encoding processing of the high frequency band data has ended, the quantization parameter of the low frequency band data is set based on the generated code amount of the high frequency band data. A coefficient quantizing unit, coefficient encoder, code amount detector, and quantization parameter updating unit operate to encode the low frequency band data into codes within a low frequency band target code amount.

Abstract: Various embodiments of the present invention provide systems and methods for synchronizing data processing. As one example, a method for synchronizing data processing is disclosed that includes receiving a data input, and sampling the data input at a sample period to generate a sample set. A first pattern is received and a first periodic boundary associated with the first pattern is identified. In one particular case, the first pattern is a preamble pattern included as sector data on a storage medium, and the first periodic boundary is a 4T boundary. Further, a second pattern is detected in the sample that is used to establish a second periodic boundary. In one particular case, the second pattern is a SAM pattern included as sector data on a storage medium, and the second periodic boundary is a 1T boundary. Based at least in part on the first periodic boundary and the second periodic boundary, a time to transmit or assert a data-found signal is determined.

Abstract: Provided are a method, servo channel, and tape drive for determining a reference waveform used by a correlator in a servo channel. Sequences of servo signal samples are provided from read servo signals read from a servo pattern on a recording medium. A determination is made of a reference waveform based on the sequences of servo signal samples and the reference waveform is forwarded. Interpolated servo signals are generated. The interpolated servo signal samples and the forwarded reference waveform are received to generate correlation output samples. Position and velocity information are calculated from the correlation output samples.

Abstract: Systems and methods for managing errors on a magnetic tape having a plurality of partitions accessed by a tape drive having an associated tape drive processor in communication with a host computer having an associated host processor include receiving mapping information from the host computer that designates at least first and second logically adjacent partitions for reading/writing consecutive data, receiving a read/write request to transfer the consecutive data for the first and second partitions, detecting a data error when attempting to read/write the data for the second partition and communicating a corresponding data error message to the host computer, and receiving modified mapping information from the host computer that designates a third partition as logically adjacent to the first partition for reading/writing the consecutive data.

Abstract: A servo sector address and a track address of a recording medium of a disk drive are encoded into a combined address value. The combined address value is stored in a combined address field that has fewer bits than the total bits required to uniquely encode the servo sector address and the track address. The position of a transducer head, indicated by the servo sector address and the track address, is determined by reading encoded values from two consecutive servo sectors on the recording medium and then decoding the encoded values.

Abstract: A system includes a self-servo-write (SSW) module, a read module, and a write module. The SSW module writes servo spirals on a magnetic medium of a hard disk drive (HDD) via a write head of the HDD. The read module reads the servo spirals via a read head of the HDD and generates read signals. The write module writes non-servo data on the magnetic medium via the write head based on the read signals before the SSW module writes servo wedges on the magnetic medium.

Abstract: A method and apparatus for writing data to a tape is disclosed. A plurality of data segments are written onto a tape simultaneously. Any data segments written to the tape that needs to be rewritten are identified. Each data segment that needs to be re-written is accumulated. The accumulated data segments are written to tape when a full set of data segments have been accumulated. The re-written data segments each have a first field in a header that designates itself and a second field in the header that designates a second re-written data segment.

Abstract: Systems and methods for synchronizing write signals are disclosed. In one embodiment, a compensation system is implemented within a disk drive that receives a synchronization signal read from a patterned magnetic disk by a read head. The compensation system processes the synchronization signal to compensate for noise sensed by the read head while a write head writes to the disk based on a write signal. The adjustment module is operable to adjust the write signal based on the processed synchronization signal so that the write signal is synchronized to the pattern on the disk.

Abstract: A video recording system is provided in which reliability of information supplied from a video camera to control recording and the like is improved when video being obtained by a video camera is recorded in one or more VTRs. In the video recording system, the video camera multiplexes: control information to control the VTR in accordance with an operational status of an operation unit of the video camera and a video signal from an imaging unit of the video camera, and transmits the result to the VTR as a transmission serial digital signal. The VTR separates the video signal and the control information from the serial digital signal and controls a video recording system of the VTR based on the control information.

Abstract: A magnetic transfer device and method are provided. A magnetic field generating structure comprises a pair of permanent magnets connected to a return yoke. Respective magnetic poles of the magnets, of a different polarity from one another, oppose each other with a conjoined body disposed therebetween. The magnetic field generating structure is moved from a position at an outer periphery of the conjoined body, to a position at an inner periphery of the conjoined body, and then moved from the position at the inner periphery across the conjoined body toward the outer periphery, to a position outside of the conjoined body. The return yoke is positioned at a radially more outward position, toward the outer periphery, than are the permanent magnets. The movement of the magnetic field generating structure is carried out while maintaining a constant distance from the rotating conjoined body.

Abstract: Methods, computer systems, and computer program products are provided for determining an access sequence of a plurality of data groups stored on a tape medium. A first data group in the access sequence is selected based on which data group in the plurality of data groups has a beginning closest to a current position of the tape medium. A second data group in the access sequence is selected based on which remaining data group in the plurality of data groups has a beginning closest to an end of the first data group in the access sequence.

Abstract: A data storage medium comprises a plurality of data regions, and a plurality of servo regions configured to provide positioning information to a reading device. Each of the plurality of data regions corresponds to more than one of the plurality of servo regions. The more than one of the plurality of servo regions are configured to provide positioning information to the reading device at discrete times corresponding to a data operation of a corresponding data region.

Abstract: A disk drive is disclosed comprising a head actuated over a disk having a plurality of tracks, wherein each track comprises a plurality of data sectors each assigned a physical block address (PBA). A first write command is received identifying a number of logical block addresses (LBAs) and write data. A header identifier is written to a first data sector that identifies a beginning of the first write command. The write data is written to a plurality of the data sectors and after writing the write data, a footer identifier is written to a second data sector that identifies the end of the first write command. The LBAs are written to at least one of the first data sector and the second data sector.

Abstract: A storage medium includes multimedia image data, and text-based subtitle data for displaying subtitles on an image based on the multimedia image data, wherein the text-based subtitle data includes dialog information indicating subtitle contents to be displayed on the image, style information indicating an output style of the dialog information, and partial style information indicating an output style applied to a portion of the dialog information. Accordingly, subtitles can be provided in a plurality of languages without being limited to a particular number of units of subtitle data. In addition, subtitle data can be easily produced and edited. Likewise, an output style of the subtitle data can be changed in a variety of ways. Also, a special style can be applied in order to emphasize a portion of the subtitles.

Abstract: Methods and apparatus are provided for detecting a syncMark in a read channel, such as a hard disk drive. A syncMark is detected in a sector in an iterative read channel by obtaining a sector signal from a storage media, the sector signal comprising a first syncMark, data and a second syncMark substantially at an end of the sector; determining whether the first syncMark is detected in the sector signal; searching for the second syncMark if the first syncMark is not detected in the sector signal; and detecting and decoding the sector signal based on a detection of the second syncMark. The second syncMark may be positioned, for example, following data in the sector signal. The second syncMark can be searched for in a window within the signal sector that is based on an estimated location of the first syncMark.

Abstract: Servo patterns for patterned media. The servo pattern includes specification of cylinder/track ID with and without a Gray code. The servo pattern space is minimized by the optimum usage of the islands. This is achieved by island allocation rules to take advantage of non-magnetic island. The island allocation also provides for easier lift-off. Logic is used to encode and decode the Gray code. Further, the Gray code is designed to stabilize the magnetic island/non-magnetic island ratio to allow for easier manufacture.

Abstract: A hard disk drive that includes a disk with data written onto a plurality of tracks, a spindle motor that rotates the disk, and a head that is coupled to the disk. The disk drive also includes a circuit that writes data onto a first writable shingle band of tracks if the first writable shingle band is adjacent to a guard band of tracks. The first writable shingle band includes a number of tracks that is a function of a head width. The guard band of tracks is capable of becoming a writable shingle band. Changing the designation of a shingle band between guard and writable creates floating guard bands. The creation of floating guard bands allows for the writing of a single band without having to move and restore adjacent tracks until reaching a fixed guard band as required in the prior art.

Abstract: To avoid the occurrence of a recording error by suppressing the influence that a magneto-static interaction acting between the pattern dots exerts on a recording process and expand a margin for recording synchronization timing lag or tracking misregistration on the pattern dot. Each pattern dot has a structure in which a plurality of parts having different magnetization reversal fields are bonded with exchange interaction in the in-plane direction of a medium, substrate. The positional relationship between the parts having different magnetization reversal fields is substantially coincident between the adjacent pattern dots, which are arranged to have a gradient of magnetization reversal field in a track direction or track transverse direction. Further, the recording is performed by adapting a gradient of recording magnetic field to the gradient of magnetization reversal field. Other methods and systems are described as well.

Abstract: This application discloses a hard disk drive and a disk employing Discrete Tracks each including a land with a groove at a first depth with sectors of each track separated by servo pattern wedges with a variable second land and a variable second groove possessing widths and a second depth for the grooves differing from the first widths and depth of the groove of the sectors. The second depth optimizes the stability of the flying height of a slider over both sectors and servo pattern wedges, removing the possibility of added vibrational modes adversely affecting the slider's normal operations of reading, writing and flying above the disk surface. This also discloses the disks and their manufacture of disk surfaces with these sector zones and servo pattern wedges.

Abstract: To synchronize a write/read frequency with media with high precision even when a write head is positioned in a different zone in a magnetic recording/reproducing device equipped with patterned media formed with writing hit patterns and having a zoned format function, a write head is positioned on a recording track in the vicinity of a boundary between zones, and the write head is positioned in a different zone from the zone in which the read head is positioned, the preamble pattern in the zone in which the read head is positioned is reproduced, a difference between frequencies of the preamble patterns of the zones is compensated to determine a write frequency used for writing data into a desired track, and then start timing for writing is determined based on a synchronization pattern obtained at the position of the read head. Other systems and methods are presented as well.

Abstract: A length of a separator to be skipped on the storage disk is compared with a threshold. The threshold is associated with a maximum value for which a timing loop is able to be paused without causing the timing loop to have inaccurate timing. If the length is greater than the threshold, a first split sector format is assigned to the split sector and that information is recorded. In such cases, a first portion and a second portion both include synchronization information. If the length is less than the threshold, a second split sector format is assigned to the split sector and that information is recorded. In such cases, the first portion includes synchronization information and the second portion of the split sector excludes synchronization information.

Abstract: A method for detecting a servo address mark (SAM) of a servo sector of a disk of a disk drive during a servo field sync-up operation is disclosed. The method includes: detecting a start of a preamble; opening a SAM search window to detect the SAM; and continuing to detect the presence of the preamble during a SAM search time period. Further, the method discloses that: if the preamble is detected, the SAM search window is continued; and if the preamble is not detected, and the SAM is not detected, the SAM search window is closed.

Abstract: Methods, apparatuses, and systems implementing analog techniques to decode signals extracted from servo wedges of computer-readable storage media. A digital signal representing a repeatable runout (RRO) signal included in an analog signal of a computer-readable storage medium is obtained. The RRO signal includes a preamble that represents a magnitude of the RRO signal, and data. The digital signal includes a digital representation of the preamble. An estimate of the magnitude of the RRO signal is determined based on the digital representation. The estimate is compared with a specified level to generate an error signal based on a difference between the two. The provision of the error signal, for application to a subsequent RRO signal of the computer-readable storage medium, is delayed. The RRO signal is amplified prior to being represented as the digital signal to match a value established to decode the RRO signal.

Abstract: A method of making a disc for a computer disc drive and a disc made in accordance with the same. The disc includes a deposited magnetic layer of a thin film medium over a disc-shaped substrate. A master pattern having a plurality of tracks is recorded on the disc. Each track on the disc includes a plurality of magnetic islands, each having a size and magnetic properties. The size and/or magnetic properties of one or more of the magnetic islands of each track are modulated such that each track has a modulation frequency, so as to imprint a magnetic topology on the disc. The modulation frequency of each track is either a fundamental frequency or an overtone of the fundamental frequency.

Abstract: Methods and apparatus for interleaving data in a multitrack tape drive and for writing data on a multitrack tape in the tape drive. One method includes: partitioning the data into m(2n+k) data blocks, where each data block has a logical array of rows and columns of data bytes; error-correction coding a row and a column of the logical array to produce an encoded block; assigning the coded row to a respective location in a logical interleave array having L rows and 2n+k columns of locations; and writing a sequence of assigned coded rows simultaneously in respective data tracks on the multitrack tape. The coded row is assigned such that the minimum Euclidean distance on the multitrack tape between the coded rows is maximized. The apparatus includes units for performing the methods and the computer program product includes a program code means for causing a computer to perform the methods.

Abstract: A method for physically laying out data on tape is disclosed herein. In one embodiment, such a method includes receiving a data set, wherein the data set includes S sub data sets (SDSs) of fixed size and each SDS includes N codeword interleaves (CWIs). The method further distributes the CWIs for the S SDSs across T tracks on a physical tape medium such that the distances between CWIs of the same SDS are substantially maximized on the physical tape medium. To maximize the distances, the method periodically rotates the tracks within the data set by a track rotation value R, wherein the number of tracks T is equal to 2k, and the track rotation value R is equal to 2k?1?1. A corresponding apparatus is also disclosed herein.

Abstract: A method for the production of a magnetic recording medium includes the steps of forming a magnetic layer on a nonmagnetic substrate, injecting atoms into portions of the magnetic layer to cause the portions to be demagnetized or allowed to acquire amorphousness, thereby forming a magnetically separated magnetic recording pattern, the step of injecting atoms including the steps of applying to a surface of the formed magnetic layer an SOG film as a resist, partly removing or thinning the resist, and irradiating the surface with atoms, thereby partly injecting atoms into the magnetic layer through the portions of the magnetic layer from which the resist is removed or in which the resist is thinned.

Abstract: A bit-patterned magnetic media (BPM) includes with respect to each data track a first sub-track and a second sub-track, each sub-track comprised of a plurality of bit-islands. A transducer head placed over a data track generates a readback signal. Channel response circuitry demodulates the readback signal and detects fine positioning information based on a comparison of a readback signal generated in response to the first sub-track and a readback signal generated in response to the second sub-track.