Lg Electronics Inc.

Hyung Jin Jeon

Sang On Park

Seong Pyo Hong

A track jump method for an optical recording/reproducing medium is provided. In the track jump method, once a track jump command is input, a track jump operation is held until a falling edge of a header mask signal is detected. The track jump starts at the falling edge of the header mask signal and ends before a rising edge of the header mask signal so that a TZC signal is not influenced by a header during the track jump. Therefore, the track jump can be exactly and stably performed. In particular, when the track jump command is input, a PLL of a wobble signal is inhibited, and a PLL-wobble signal is held to a previous value obtained before the track jump is performed, during the track jump, or a header mask signal is generated using a read channel signal which is not influenced by a wobble period, until a wobble signal becomes stable after a trackjump. During a normal servo, a header mask signal is generated using a PLL-wobble signal to mask a header area. Therefore, a header area coming first after the trackjump is completed can be stably masked, thereby preventing a system from being unstable due to a header during the track jump.

Header mask signal generating track jump method for a recording medium

A track jump method for an optical recording/reproducing medium is provided. In the track jump method, once a track jump command is input, a track jump operation is held until a falling edge of a header mask signal is detected. The track jump starts at the falling edge of the header mask signal and ends before a rising edge of the header mask signal so that a TZC signal is not influenced by a header during the track jump. Therefore, the track jump can be exactly and stably performed. In particular, when the track jump command is input, a PLL of a wobble signal is inhibited, and a PLL-wobble signal is held to a previous value obtained before the track jump is performed, during the track jump, or a header mask signal is generated using a read channel signal which is not influenced by a wobble period, until a wobble signal becomes stable after a track jump. During a normal servo, a header mask signal is generated using a PLL-wobble signal to mask a header area. Therefore, a header area coming first after the track jump is completed can be stably masked, thereby preventing a system from being unstable due to a header during the track jump.

Track jump method for a recording medium

The present invention relates to an apparatus and method for detecting non-recording regions of an optical recording medium for recording data or reproducing the recorded data by detecting header regions of the optical recording medium. For this purpose, in the apparatus for detecting non-recording regions of the optical recording medium having a plurality of header regions of different phases arranged between writable data regions in which the information capable of recognizing a reference frequency is wobbled on tracks, in order to distinguish the data regions by their shapes, the apparatus for detecting non-recording regions of the optical recording medium in accordance with the present invention includes a header region detection unit for detecting the plurality of header regions, a header region verification unit for verifying the detected header regions and outputting verified signals, a wobble-PLL unit for outputting PLL-wobble signals by phase locking upon receipt of wobble signals recorded on the tracks of the optical recording medium, and a counter for outputting header mask signals by counting the number of output pulses of the wobble-PLL unit upon receipt of the PLL-wobble signals on the basis of the verified signals.

Apparatus and method for detecting non-recording regions of an optical recording medium

Method for controlling track jump in an optical recording medium for writing/reading data on/from land/groove tracks having depths different from each other in a direction of a beam incident, including the steps of (1) adjusting an offset of a servo error signal generated by using an optical signal reflected at the optical recording medium consistent to the land track, (2) adjusting an offset of a servo error signal generated by using an optical signal reflected at the optical recording medium consistent to the groove track, (3) selecting the servo error signal having the offset adjusted consistent to the land/groove track in the step (1) or (2) in response to a land/groove switching signal, (4) receiving a track jump command, and determining the track jump command of being an 'N'('N' is an odd numeral) track jump command, and (5) if the track jump command is determined of being an &lsquo;N&rsquo;(&lsquo;N&rsquo; is an odd numeral) track jump command in the step (4), after switching the land/groove switching signal and carrying out an &lsquo;N&rsquo; track jump, carrying out servo by using a servo error signal selected in response to the land/groove switching signal in the step (3).

Method for controlling track jump in optical recording medium

A circuit it for deciding classes resulting from 8.times.8 DCT or 2.times.4.times.8 DCT blocks includes a block forming circuit for converting a digital video signal into a predetermined block structure, a mode deciding section for detecting still/motion of the digital video signal block to generate a mode signal, a DCT section for selectively performing the 8.times.8 DCT or 2.times.4.times.8 DCT upon the block supplied from the block forming circuit according to the mode signal of the mode deciding section, a controlling section for controlling DCT data coefficients output according to the mode signal from mode deciding section, a scanning section for zig-zag scanning data in an 8.times.8 activity detecting pattern upon the output of the 8.times.8 DCT block from the DCT section and zig-zag scanning data in a 2.times.4.times.8 activity detecting pattern upon the output of the 2.times.4.times.8 DCT block under the control of the controlling section, a comparative circuit for comparing the data coefficient values from the scanning section with threshold values of a predetermined number, and a class deciding section for deciding the classes according to the comparison values from the comparative circuit. Thus, the class of corresponding block is decided by using the activity detecting pattern differently produced by the 8.times.8 DCT block and 2.times.4.times.8 DCT block to minimize loss of a horizontal edge of the 2.times.4.times.8 DCT block, thereby preventing degradation of picture quality.

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Seoul, South Korea

Hyung Jin Jeon