14results about "Signal processing using self-clocking codes" patented technology

Novel tools and techniques are provided for implementing synchronization signal ("Sync Mark") detection using multi-frequency sinusoidal ("MFS") signal-based filtering. In various embodiments, a computing system may detect a location of a Sync Mark within a data signal, by using MFS signal-based filtering and a sliding window comprising successive search windows each having a bit length corresponding to a bit length of the Sync Mark to identify a portion of the data signal having a magnitude indicative of the Sync Mark. The computing system may refine the location of the Sync Mark within the data signal, by performing a phase measurement on the identified portion of the data signal having the magnitude indicative of the Sync Mark to identify a sub-portion of the identified portion of the data signal, the identified sub-portion having a phase indicative of the Sync Mark, the phase measurement being performed based on the MFS signal-based filtering.

To provide a magnetic recording information processing device that reads information from a magnetic recording medium such as a magnetic card, in which information can be stably read over a wide range of head-to-medium speeds while suppressing cost increases.SOLUTION: A magnetic recording information processing device includes: an AD conversion unit 21 that converts a magnetic reproduction waveform into a digital signal; a memory 22 that accumulates the converted digital signal as data in a first sampling period; a thinning-out processing unit 23 that samples the converted digital signal at a second sampling period that is longer than the first sampling period; a demodulation processing unit 24 that executes a demodulation processing; and a control unit 25 that makes the demodulation processing unit 24 execute the demodulation processing in real-time based on the digital signal sampled by the thinning-out processing unit 23 and makes the demodulation processing unit 24 execute the demodulation processing based on the data accumulated data in the memory when the demodulation processing in real-time fails.SELECTED DRAWING: Figure 1

The optical disk device of the present disclosure is characterized in that a signal obtained by extracting an adjacent track component from a playback signal of a target track is generated and phase error is detected from mutual correlation with a playback signal of the adjacent track, whereby resampling is performed so that the playback signal of the target track and the playback signal of the adjacent track take on adjacent signal waveforms at the same angular position.

To provide a method for enabling continuous recording in an ISO Basic Media File Format (ISOBMFF) file or similar format in situations where the length of the file is not known in advance.SOLUTION: A method includes a step of initiating recording of an ISOBFF file storing a file header, a body including media data, and a moov header. Writing the file beyond an expected size includes a step of expanding the file to store new media data, writing a new moov header to an end of the file, and updating the file header to enable identification of the new moov header. As progressing, the moov header is periodically updated and the new media data can be added to the media data. Adding the new media data includes discarding the old moov header by overwriting a section in which the old moov header was stored with data associated with the new media.SELECTED DRAWING: Figure 1

The present disclosure describes aspects of pulse-based writing for magnetic storage media. In some aspects, a pulse-based writer of magnetic storage media determines that a string of data bits having a same polarity corresponds to a magnet longer than a threshold associated with a magnetic media writer. The pulse-based writer inserts, into the string of data bits, a transition to a polarity opposite to the same polarity of the string of data bits. The string of data bits including the inserted transition is then transmitted to the magnetic media writer to cause a write head of the writer to pulse while writing the magnet to magnetic storage media. Various aspects may also implement a control signal to mask a transition or control polarity of the magnetic media writer. By so doing, magnets may be written to the magnetic storage media more efficiently or with less distortion to neighboring tracks.

The present invention discloses a method for playing audio based on an SPI controller, comprising: sampling audio data at a set sampling frequency; converting the format of the audio data into a PCM-formatted audio file; converting the numerical value of the audio file into PWM data; configuring the transmission rate of the SPI controller according to the sampling frequency of the audio file; converting the PWM data into SPI data; using multiple buffer memories to write corresponding SPI data, and transmitting the SPI data in turn to the SPI controller via a DMA controller; the SPI controller continuously transmitting the SPI data at the configured transmission rate to achieve audio file playback. The present invention also discloses an electronic device and a computer storage medium, which ensure the quality and speed of audio playback.

The present application provides an MP4 file processing method, apparatus, electronic device, and storage medium. The method includes: when recording an MP4 file, inserting media basic information at the starting position of the mdat box, and inserting extension information before each recorded data block, where the extension information indicates the data block length, so that when the MP4 file is not completely recorded, the player determines the actual file length, determines the offset position of the current data block, and repairs the MP4 file based on the media basic information, the recorded data blocks, and the extension information before the recorded data blocks. The present application solves the problem that an MP4 file cannot be played due to incomplete recording.

The present technology relates to a recording medium, a recording device, a recording method, a reproduction device, and a reproduction method that make it possible to correctly reproduce multi-level code that has been recorded at high density. According to the present invention, a recording medium stores: M-ary multi-level code produced by coding user data into an M-ary (d,k) RLL code for which M is at least 3; and an M-ary specific pattern that repeats a run that is longer than the longest run k of the multi-level code. Reproduction from the recording medium is performed, and the multi-level code is decoded in accordance with the specific pattern. The present technology can be applied, for example, to recording media and recording / reproduction devices that perform recording / reproduction to / from a recording medium.

The present invention discloses a coding and decoding method and a reading and writing method of a fourth-order RLL (1,7) modulation code, which belongs to the field of optical storage technology, comprising: a coding step: dividing user data into 6-bit source data, converting each source data into a 5-bit channel code element according to a coding and decoding table, splicing them in sequence, inserting a merging bit between two adjacent channel code elements to obtain an RLL sequence; a decoding step: removing a merging bit every 5 bits of the RLL sequence to obtain a channel code element, and splicing each signal element according to the coding and decoding table. Channel symbols are converted into 6-bit source data, and the source data are sequentially concatenated to obtain user data. A codec table records the correspondence between 64 types of 6-bit source data and 64 types of 5-bit channel symbols. The channel symbols are 64 of 0000X, 00X0X, 0X00X, X000X, X0X0X, 000X0, 0X0X0, X00X0, 00X00, X0X00, 0X000, and X0000. X ranges from 1 to 3. The present invention can significantly increase the capacity of an optical storage system without changing optical parameters.

An embodiment provides a magnetic disk device and a post-code writing method capable of improving format efficiency. The magnetic disk device of this embodiment includes: a disk having a first area with a first format efficiency and a second area with a second format efficiency lower than the first format efficiency; a head for writing data to and reading data from the disk; and a controller for selecting a first post-code to be written to the first area and a second post-code to be written to the second area from a plurality of post-codes, and writing the selected post-codes to the first area and the second area, respectively.

Embodiments of the present disclosure relate to pulse-based writing for magnetic storage media. The present disclosure describes aspects of pulse-based writing for magnetic storage media. In some aspects, a pulse-based writer of magnetic storage media determines that a string of data bits having a same polarity corresponds to a magnet that is longer than a threshold value associated with the magnetic media writer. The pulse-based writer inserts a transition into the string of data bits to a polarity opposite the same polarity of the string of data bits. The string of data bits, including the inserted transition, is then communicated to the magnetic media writer to cause a write head of the writer to pulse at a time to write the magnet to the magnetic storage media. Various aspects can also implement control signals to mask transitions or control polarity of the magnetic media writer. By doing so, the magnet can be more efficiently written to the magnetic storage media or have less distortion to adjacent tracks.

Semantic communication systems and methods of implementing semantic communication are disclosed. A method includes obtaining a dataset of semantic embeddings. The semantic embeddings include semantic information extracted from multimodal messages using a transformer model. The method also includes using the semantic embeddings to train one or more neural networks, and obtaining binary codewords corresponding to the semantic embeddings for transmission based on training the one or more neural networks.