Systems and methods are disclosed for error recovery in a digital data channel. In an error recovery approach when the hardware fails to recover a sector, the sample for that sector can be saved along with a metric measure that indicates the quality of the sample. This process can begin from a first on-the-fly receiving and decoding of data. During each step of error recovery, a retry attempt may either use samples obtained during a new decoding attempt or may use a sample, or a combination of samples, having the best metric from an earlier attempt, or a combination of earlier attempts, to perform the recovery during a current retry recovery attempt.

A method for accessing a shingled magnetic recording (SMR) disk is provided. The method includes: receiving, by the server, a data operation request, where the data operation request includes address information of target data; determining, according to the address information, a target storage zone in the SMR disk that corresponds to the target data; determining that there is write pointer information of the target storage zone in a cache, and obtaining the write pointer information from the cache, where the write pointer information is address information of latest stored data in the target storage zone; generating a data operation instruction according to the write pointer information and the address information of the target data, where the data operation instruction is used to perform an operation on the target data; and sending the data operation instruction to the SMR disk. Embodiments of the present disclosure are applied for a server to access an SMR disk.

It is determined, when a region of a moving object detected from an image overlaps a fixed region in the image, whether to superimpose a first mask image to be drawn in the region of the moving object on a second mask image to be drawn in the fixed region, based on an image feature amount of the region of the moving object. The drawing of the first mask image is controlled in accordance with this determination result.

It is determined, when a region of a moving object detected from an image overlaps a fixed region in the image, whether to superimpose a first mask image to be drawn in the region of the moving object on a second mask image to be drawn in the fixed region, based on an image feature amount of the region of the moving object. The drawing of the first mask image is controlled in accordance with this determination result.

According to one embodiment, in a storage device, a selection circuit selects one mapping rule from a plurality of mapping rules in which each of bit labels having a bit length of (n+1) or more is mapped to n M-ary symbols, when M is defined as an integer of 3 or more and n is defined as an integer of or more. A first conversion circuit converts a data block in data into an M-ary symbol sequence using the selected one mapping rule. A second conversion circuit converts the converted M-ary symbol sequence into an M-step pulse width signal. The recording medium records the converted M-step pulse width signal. A readback circuit equalizes the signal read from the recording medium to the M-ary symbol sequence and restores the data.

The techniques described herein relate to methods, apparatus, and computer readable media configured to access multimedia data comprising a hierarchical track structure with a first track of a first sequence of temporally-related media units at a first level, and a second track at a second level comprising metadata specifying a temporal track derivation operation. The metadata includes a set of one or more operations to perform on the first track, each operation including a unit duration of the first sequence and a start unit in the first sequence. The temporal track derivation operation is performed on a set of media units comprising at least the first sequence, and includes applying the set of one or more operations to temporally modify the first sequence to generate second media data for the second track that includes a second sequence of temporally-related media units from the set of media units.

Zone self-servo write (SSW) technology is disclosed that leverages two clock signals synchronized in parallel to transition between zones to write servo patterns at different frequencies while minimizing error rate despite the different frequencies. Two separate clock signals (clocks) are used to locate and lock to different reference spirals. By updating both clocks in parallel instead of in series, error rate for writing while stepping up frequency across zones is reduced.

Systems and methods for reading data are provided herein using a data archive architecture controlled by a head server. The head server can read data in a contiguous manner across multiple storage devices for data that has been partitioned into multiple portions and spread across the multiple storage devices. Portions of a first object can be transmitted and read from a first subset of storage devices and portions of a second object can be transmitted and read from a second subset of storage devices. The head server can increment a read pointer based on a length of the portions of the first object to a determine a read location of different portions of the first object or the second object. The head server can identify different read location to read sub sequent of different portions of multiple objects using one or more lengths of the objects or portions of the object.

A play back device includes a readout unit and a playback unit. The readout unit reads out an encoded main video stream and an encoded sub-video stream that are recorded in a recording medium. The sub-video stream is a sub-video that is to be superimposed on the main video and displayed. The playback unit plays the main video stream and the sub-video stream that have been read out. The sub-video stream includes multiple sets, each set including a first sub-video stream for a first luminance dynamic range and a second sub-video stream for a second luminance dynamic range, which is wider than the first luminance dynamic range. In the same set in the multiple sets, a registration order of the first sub-video stream in the first database and a registration order of the second sub-video stream in the second database are the same.

A tape drive-implemented method, according to one embodiment, includes: using formatting information which corresponds to a magnetic tape loaded in the tape drive to identify wraps on the magnetic tape. Identifying wraps on the magnetic tape includes: identifying an outermost wrap on the magnetic tape on a first side of the magnetic tape, and identifying an outermost wrap on the magnetic tape on a second side of the magnetic tape. A procedure is also performed for each of the wraps identified using the formatting information. Performing the procedure for a given one of the wraps includes: sending one or more instructions to position a magnetic head of the tape drive over the given wrap, and collecting PES information which corresponds to the given wrap.