Motion video signal processing for recording or reproducing – Local trick play processing – With randomly accessible medium
Reexamination Certificate
1997-12-29
2001-03-13
Tran, Thai (Department: 2715)
Motion video signal processing for recording or reproducing
Local trick play processing
With randomly accessible medium
C386S349000, C386S349000
Reexamination Certificate
active
06201926
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an apparatus for recording a digital picture signal resulting from a compression process using orthogonal transform.
2. Description of the Related Art
A digital picture signal conforming to the MPEG standards results from a compression process using orthogonal transform. Such an MPEG digital picture signal represents a sequence of frames including intra-frames and inter-frames. Here, the intra-frames are generated by an intra-frame encoding process while the inter-frames are generated by an inter-frame predictive encoding process.
There is a digital VTR (video tape recorder) which records a digital picture signal on a magnetic tape. A typical digital picture signal to be recorded results from orthogonal transform implementing data amount compression. An example of such a digital picture signal is an MPEG digital picture signal. As previously indicated, the digital picture signal of this type represents a sequence of frames including intra-frames and inter-frames. Accordingly, on the magnetic tape loaded with the digital picture signal by the digital VTR, there is a mixture of signal segments corresponding to intra-frames and signal segments corresponding to inter-frames. Generally, the positions of intra-frame-corresponding signal segments on the magnetic tape have a given period. A picture can be reproduced from only one signal segment corresponding to an intra-frame while a picture can not be reproduced from only one signal segment corresponding to an inter-frame. Accordingly, a conventional technique for special playback such as high-speed search playback in a VTR of the VHS format can not be applied to special reproduction of picture information from such a digital VTR magnetic tape.
SUMMARY OF THE INVENTION
It is an object of this invention to provide an improved apparatus for recording a digital picture signal.
A first aspect of this invention provides an apparatus for recording a digital picture signal on a recording medium, comprising first means for deleting code words, which correspond to orthogonal-transform-resultant coefficients having order numbers equal to or higher than an order number “n+1”, from code words composing each 1-intra-frame segment of an input digital picture signal to generate special picture data with a frame period NS on the basis of the input digital picture signal; second means for estimating a code amount CF(nmin) of special picture data generated by deleting code words, which correspond to orthogonal-transform-resultant coefficients having order numbers equal to or higher than an order number “nmin+1”, from code words composing a 1-intra-frame segment of the input digital picture signal, where “nmin” denotes a lower limit of an order number “n”; third means for deciding the frame period NS of the special picture data and a target code amount C so that the code amount CF(nmin) estimated by the second means will be equal to or smaller than the target code amount C; fourth means for recording the input digital picture signal on the recording medium; and fifth means for recording the special picture data generated by the first means on predetermined positions in the recording medium.
A second aspect of this invention is based on the first aspect thereof, and provides an apparatus wherein the third means comprises means for deciding whether or not the code amount CF(nmin) estimated by the second means is greater than the target code amount C; means for preventing at least a next 1-intra-frame segment of the input digital picture signal from being used by the first means to generate the special picture data; and means for incrementing the target code amount C by a value equal to a code amount corresponding to the next 1-intra-frame segment of the input digital picture signal.
A third aspect of this invention is based on the first aspect thereof, and provides an apparatus further comprising sixth means for estimating a code amount CF(n) of the special picture data generated by the first means per intra-frame; seventh means for estimating a code amount CF(n+1) of special picture data generated by deleting code words, which correspond to orthogonal-transform-resultant coefficients having order numbers equal to or higher than an order number “n+2”, from code words composing a 1-intra-frame segment of the input digital picture signal; and eighth means for deciding the order number “n” so that the target code amount C will exist between the code amount CF(n) estimated by the sixth means and the code amount CF(n+1) estimated by the seventh means.
A fourth aspect of this invention is based on the first aspect thereof, and provides an apparatus further comprising sixth means for referring to motion vector data in the input digital picture signal, and thereby detecting a degree of motion in a picture represented by the input digital picture signal; and seventh means for decreasing the lower limit “nmin” as the motion degree detected by the sixth means increases.
A fifth aspect of this invention provides an apparatus for processing and recording a digital picture signal representing a sequence of frames including intra-frames and inter-frames, the intra-frames relating to segments of the digital picture signal which result from intra-frame encoding, the inter-frames relating to segments of the digital picture signal which result of inter-frame encoding, the digital picture signal having a sequence of code words related to DCT coefficients resulting from DCT block encoding, the DCT coefficients being arrangement in a given order for every block, the apparatus comprising first means for deleting code words, which correspond to DCT coefficients having arrangement order numbers higher than an arrangement order number “n”, from code words related to each of blocks composing a 1-intra-frame segment of the input digital picture signal to generate special picture data on the basis of the digital picture signal; second means for estimating an amount of the special picture data generated by the first means per intra-frame; third means for controlling the arrangement order number “n” in response to the amount of the special picture data which is estimated by the second means; fourth means for recording the digital picture signal on first areas of a recording medium; and fifth means for recording the special picture data generated by the first means on second areas of the recording medium which differ from the first areas.
A sixth aspect of this invention provides an apparatus for processing and recording a digital picture signal representing a sequence of frames including intra-frames and inter-frames, the intra-frames relating to segments of the digital picture signal which result from intra-frame encoding, the inter-frames relating to segments of the digital picture signal which result from inter-frame encoding, the apparatus comprising first means for generating special picture data on the basis of 1-intra-frame segments of the digital picture signal; second means for estimating an amount of the special picture data generated by the first means per intra-frame; third means for selectively discarding a 1-intra-frame segment of the digital picture signal, and thereby preventing said 1-intra-frame segment of the digital picture signal from being used by the first meas in response to the amount estimated by the second means; fourth means for recording the digital picture signal on first areas of a recording medium; and fifth means for recording the special picture data generated by the first means on second areas of the recording medium which differ from the first areas.
REFERENCES:
patent: 5982987 (1999-11-01), Sakazaki
patent: 6031960 (2000-02-01), Lane
patent: 6064794 (2000-05-01), McLaren et al.
Higurashi Seiji
Teranishi Yasuhiko
Yoshida Yumi
Lowe Hauptman Gopstein Gilman & Berner
Tran Thai
Victor Company of Japan Ltd.
LandOfFree
Apparatus for recording digital picture signal does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus for recording digital picture signal, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus for recording digital picture signal will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2525221