Patents by Inventor Pi-Hai Liu

Pi-Hai Liu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20100284256
    Abstract: A method for improving readability of an optical disc includes: changing a first control parameter of an optical storage apparatus that accesses the optical disc and obtaining a plurality of associated values of an index corresponding to the readability of the optical disc for respective changed/unchanged values of the first control parameter; setting the first control parameter to be an optimal value out of the changed/unchanged values of the first control parameter according to the index; changing a second control parameter with the first parameter set to be the optimal value to obtaining a plurality of associated values of the index for respective changed/unchanged values of the second control parameter; and setting the second control parameter to be an optimal value according to the index. The control parameters having their individual optimal values are utilized for further control during decoding. In addition, an associated optical storage apparatus is further provided.
    Type: Application
    Filed: May 6, 2009
    Publication date: November 11, 2010
    Inventors: Ming-Tsang Wu, Hao-Hui Yin, Chih-Ching Yu, Tzu-Ching Yang, Ya-Fang Nien, Ying-Feng Huang, Pi-Hai Liu
  • Patent number: 7791994
    Abstract: An apparatus and method for demodulating an input signal modulated from a reference signal and a data signal are disclosed. The apparatus includes a determining unit, a first calculating unit, and a comparing unit. The determining unit is utilized for determining a plurality of first calculating timings of changing different calculating modes according to the input signal. The first calculating unit is coupled to the determining unit and utilized for generating a first calculating result of the input signal according to the first calculating timings and the calculating modes thereof. The comparing unit is coupled to the first calculating unit and utilized for generating a comparing result according to the first calculating result of the input signal and a threshold setting, and for outputting a demodulated data of the input signal according to the comparing result.
    Type: Grant
    Filed: May 29, 2008
    Date of Patent: September 7, 2010
    Assignee: Mediatek Inc.
    Inventors: Yu-Hsuan Lin, Shu-Hung Chou, Pi-Hai Liu
  • Publication number: 20100097909
    Abstract: A signal pattern detecting apparatus, which is capable of detecting a physical mark in a read back signal being read from an optical disc, includes a matching signal generator, a signal comparing device, and a decision circuit. The matching signal generator is utilized for generating a matching signal, capable of being utilized to identify the physical mark, according to a reference clock and a wobble clock. The signal comparing device is electrically connected to the matching signal generator, and utilized for comparing the matching signal with a wobble data signal to generate a comparison signal. The decision circuit is electrically connected to the signal comparing device, and utilized for generating an indication signal according to the comparison signal and a threshold value. Both the wobble data signal and the wobble clock are derived from the read back signal.
    Type: Application
    Filed: December 25, 2009
    Publication date: April 22, 2010
    Inventors: Chun-Nan Chen, Wen-Yi Wu, Pi-Hai Liu
  • Patent number: 7668061
    Abstract: A method utilized for detecting a physical mark in a signal read from an optical disc, including: generating a matching signal capable of being utilized to identify the physical mark according to a reference clock and a wobble clock; generating a comparison signal by comparing the matching signal and a wobble data signal; determining whether a period of which the level of the comparison signal surpass a predetermined level within a predetermined period is greater than a threshold or not; and if the period greater than the threshold, generating an indication signal corresponding to the location of the physical mark. Wherein the wobble data signal and the wobble clock is generated according to the read back signal.
    Type: Grant
    Filed: June 17, 2005
    Date of Patent: February 23, 2010
    Assignee: MediaTek Incorporation
    Inventors: Chun-Nan Chen, Wen-Yi Wu, Pi-Hai Liu
  • Publication number: 20090296545
    Abstract: An apparatus and method for demodulating an input signal modulated from a reference signal and a data signal are disclosed. The apparatus includes a determining unit, a first calculating unit, and a comparing unit. The determining unit is utilized for determining a plurality of first calculating timings of changing different calculating modes according to the input signal. The first calculating unit is coupled to the determining unit and utilized for generating a first calculating result of the input signal according to the first calculating timings and the calculating modes thereof. The comparing unit is coupled to the first calculating unit and utilized for generating a comparing result according to the first calculating result of the input signal and a threshold setting, and for outputting a demodulated data of the input signal according to the comparing result.
    Type: Application
    Filed: May 29, 2008
    Publication date: December 3, 2009
    Inventors: Yu-Hsuan Lin, Shu-Hung Chou, Pi-Hai Liu
  • Patent number: 7623424
    Abstract: An apparatus for identifying the address in pregroove (ADIP) of a Blu-ray disc is described. The apparatus uses a statistical scheme or distance-finding scheme to find the position of a predetermined minimum shift keying (MSK) mark or the first MSK mark, i.e. a bit sync unit, from an ADIP unit to identify data of the ADIP unit. The present invention doesn't have the error propagation effect occurring in the prior art so that the error rate for ADIP identification can be greatly reduced.
    Type: Grant
    Filed: January 26, 2005
    Date of Patent: November 24, 2009
    Assignee: Media Tek Inc.
    Inventors: Chun-Nan Chen, Wen-Yi Wu, Pi-Hai Liu
  • Patent number: 7606340
    Abstract: A phase detection device comprising an analog-digital converter, an interpolator, and a determining unit. The analog-digital converter receives an analog signal and converts the analog signal to a digital signal according to a plurality of digital sampling points. The interpolator generates a plurality of interpolation points according to a predetermined amount of digital sampling points. The determining unit obtains a phase of the ZC point according to the interpolation points or the digital sampling points.
    Type: Grant
    Filed: September 9, 2005
    Date of Patent: October 20, 2009
    Assignee: Mediatek Inc.
    Inventors: Yuh Cheng, Pi-Hai Liu, Meng-Ta Yang
  • Patent number: 7583729
    Abstract: An adaptive equalizer and the related method are disclosed. The adaptive equalizer is capable of adjusting its own equalization coefficients, and includes a reference signal generator for generating a reference signal according to a first reference source, an equalization unit for generating an equalized signal by processing a received signal through a plurality of equalization coefficients, a weighted signal generator for generating a weighted signal according to a second reference source, and a coefficient adapting circuit for adjusting the equalization coefficients according to the reference signal, the equalized signal, the weighted signal, and the received signal.
    Type: Grant
    Filed: August 8, 2005
    Date of Patent: September 1, 2009
    Assignee: MediaTek Inc.
    Inventors: Pi-Hai Liu, Meng-Ta Yang
  • Patent number: 7423561
    Abstract: A modulation method for symbols in a frame of a compact disc includes the steps of receiving a plurality of data words, modulating each data word into a code word of a corresponding data symbol, and providing a plurality of combinations of potential merge bits to be inserted between successive symbols of the frame. At least one combination of candidate merge bits is generated according to the plurality of combinations of potential merge bits, a data symbol immediately preceding the location of the candidate merge bits, and a data symbol immediately succeeding the location of the candidate merge bits. The combination of candidate merge bits which minimizes (optimizes) the absolute cumulative DSV is selected when a subsequent group of possible combinations of candidate merge bits is detected or after a predetermined delay, and the selected combination of candidate merge bits is inserted between the two successive data symbols.
    Type: Grant
    Filed: June 5, 2007
    Date of Patent: September 9, 2008
    Assignee: Mediateck Inc.
    Inventors: Hsin-Cheng Chen, Pi-Hai Liu, Ming-Yang Chao
  • Patent number: 7397396
    Abstract: A modulation system includes an encoder for transferring data words to tentative code words. A DSV control bit generator determines the value of a DSV control bit according to the data words or the tentative code words to optimize the cumulative DSVs corresponding tentative code words, wherein the DSV control bit generator determines the value of a current DSV control bit when at least a subsequent DSV control bit is detected. A final code word generator generates final code words according to the determined DSV control bit and the tentative code words.
    Type: Grant
    Filed: October 18, 2006
    Date of Patent: July 8, 2008
    Assignee: MediaTek Inc.
    Inventors: Hsin-Cheng Chen, Pi-Hai Liu, Ming-Yang Chao
  • Patent number: 7348900
    Abstract: A modulation method for a first data string having a plurality of symbols is disclosed. The method includes: appending a data string to the first data string to form a second data string; and converting the second data string to a code word sequence by converting each of the symbols in the first data string to a code word according to predetermined modulation rules and a symbol set selected from the second data string. Each code word has a first fixed number of bits, each symbol has a second fixed number of bits, and each symbol set has a fixed number of symbols.
    Type: Grant
    Filed: March 7, 2006
    Date of Patent: March 25, 2008
    Assignee: MediaTek Inc.
    Inventors: Pi-Hai Liu, Ming-Yang Chao, Jin-Bin Yang
  • Patent number: 7330137
    Abstract: An encoder and decoder for encoding data bits of a binary source signal into a stream of data bits of a binary channel signal and vice versa includes a conversion table used to map m-bit source words to codeword having a variable code length with a basic code length of n bits and a total code length of n*i bits, i being an integer of at least 1. The conversion table preserves the parity of the m-bit source words over the codeword and limits a characteristic of the codeword specified for each starting bit position in the code word.
    Type: Grant
    Filed: December 12, 2003
    Date of Patent: February 12, 2008
    Assignee: MediaTek Inc.
    Inventor: Pi-Hai Liu
  • Publication number: 20080013431
    Abstract: A method for tuning a write strategy parameter of an optical storage device, includes: writing a segment of data according to a plurality of write strategies; reading the data back and detecting a plurality of lengths, each length corresponding to a pit or a land on an optical storage medium accessed by the optical storage device; performing calculations according to the lengths and a plurality of data types to generate a plurality of calculation results, each of the data types corresponding to at least a specific target pit length or at least a specific target land length; and utilizing the calculation results to determine a proper write strategy.
    Type: Application
    Filed: July 4, 2007
    Publication date: January 17, 2008
    Inventors: CHIH-CHING YU, Pi-Hai Liu, Yuh Cheng
  • Publication number: 20070229327
    Abstract: A modulation method for symbols in a frame of a compact disc includes the steps of receiving a plurality of data words, modulating each data word into a code word of a corresponding data symbol, and providing a plurality of combinations of potential merge bits to be inserted between successive symbols of the frame. At least one combination of candidate merge bits is generated according to the plurality of combinations of potential merge bits, a data symbol immediately preceding the location of the candidate merge bits, and a data symbol immediately succeeding the location of the candidate merge bits. The combination of candidate merge bits which minimizes (optimizes) the absolute cumulative DSV is selected when a subsequent group of possible combinations of candidate merge bits is detected or after a predetermined delay, and the selected combination of candidate merge bits is inserted between the two successive data symbols.
    Type: Application
    Filed: June 5, 2007
    Publication date: October 4, 2007
    Inventors: Hsin-Cheng Chen, Pi-Hai Liu, Ming-Yang Chao
  • Patent number: 7263050
    Abstract: A system, for tuning a plurality of write strategy parameters of an optical storage device, includes: a run-length limited (RLL) meter for detecting a plurality of lengths, each length corresponding to a pit or a land on an optical storage medium accessed by the optical storage device; and a calculation module coupled to the RLL meter for performing calculations according to the lengths to generate a plurality of calculation results; wherein the write strategy parameters are tuned according to the calculation results.
    Type: Grant
    Filed: December 16, 2005
    Date of Patent: August 28, 2007
    Assignee: Mediatek Inc.
    Inventors: Pi-Hai Liu, Yuh Cheng, Chih-Ching Yu, Chih-Hsiung Chu
  • Patent number: 7260050
    Abstract: An apparatus for detecting physical marks from a wobble signal includes a matching value operation unit, a threshold value generator and a physical mark indicator. A wobble signal is converted into a matched signal by the matching value operation unit according to the waveform difference between a normal clock signal or a specific matching reference signal and itself, wherein the matching reference signal needs to highlight the existed physical mark. The physical mark indicator designates a threshold value that depends on the status of the wobble signal, and compares the matched signal with the threshold value to output a physical mark indication signal. The threshold value is selected from at least two different default values. Furthermore, a decoder is employed to convert the physical mark indication signal into wobble data with physical address information.
    Type: Grant
    Filed: October 11, 2004
    Date of Patent: August 21, 2007
    Assignee: Mediatek, Inc.
    Inventors: Pi-Hai Liu, Chun-Nan Chen
  • Patent number: 7245658
    Abstract: A read channel apparatus is disclosed for reading data recorded on an optical storage system. An exemplary sampling device samples an analog read signal generating from the optical storage system to generate a sequence of sample values. A subtractor subtracts an estimated DC offset from the sample values to generate a sequence of DC-removed sample values. An equalizer equalizes DC-removed sample values in accordance with a target spectrum to generate a sequence of equalized sample values. First and second interpolators interpolate the equalized sample values to respectively generate sequences of even-time sample values and odd-time sample values. A data sequence composed of the even-time and the odd-time sample values is substantially synchronized to the baud rate. A timing recovery controller controls the interpolators to synchronize the even-time and odd-time sample values to the baud rate.
    Type: Grant
    Filed: February 13, 2006
    Date of Patent: July 17, 2007
    Assignee: Mediatek, Inc.
    Inventors: Tzu-Pai Wang, Meng-Ta Yang, Pi-Hai Liu
  • Publication number: 20070150798
    Abstract: A method for decoding an error correction code (ECC) block includes: providing a plurality of flags, wherein each flag is utilized to label at least one codeword of the ECC block as an error-free codeword; and detecting whether a flag corresponding to a specific codeword is asserted, and skipping calculating a syndrome of the specific codeword if the flag is asserted.
    Type: Application
    Filed: December 12, 2005
    Publication date: June 28, 2007
    Inventors: Jia-Horng Shieh, Pi-Hai Liu
  • Patent number: 7236108
    Abstract: An apparatus for data recovery includes a multi-level comparison unit, a detection logic unit, and a data composer. The multi-level comparison unit compares an input signal with M different reference signal levels to generate M digital data, the number M being greater than or equal to 2. The detection logic unit is coupled to the multi-level comparison unit, and performs logic operations upon specified lengths over the M digital data obtained from the multi-level comparison unit. The data composer is coupled to the multi-level comparison unit and the detection logic unit. The data composer generates recovered data conforming with a run length encoding constraint based on the M digital data obtained from the multi-level comparison unit and the result obtained from the detection logic unit.
    Type: Grant
    Filed: October 28, 2004
    Date of Patent: June 26, 2007
    Assignee: Mediatek Inc.
    Inventors: Yuh Cheng, Pi-Hai Liu
  • Patent number: 7224295
    Abstract: The present invention provides a method and system for converting an input code into an output code. The method includes: determining a plurality of input code subsets of the input code; converting the input code subsets into a plurality of output code subsets, respectively; and merging the output code subsets to generate the output code. The system includes a splitter, for determining a plurality of input code subsets of the input code; a mapper, coupled to the splitter, for converting the input code subsets into a plurality of output code subsets, respectively; and a merger, coupled to the mapper, for merging the output code subsets to generate the output code.
    Type: Grant
    Filed: March 23, 2006
    Date of Patent: May 29, 2007
    Assignee: Mediatek Inc.
    Inventors: Jia-Horng Shieh, Pi-Hai Liu