Motion video signal processing for recording or reproducing – Local trick play processing – With randomly accessible medium
Reexamination Certificate
1994-11-18
2001-02-27
Tran, Thai (Department: 2715)
Motion video signal processing for recording or reproducing
Local trick play processing
With randomly accessible medium
C386S349000
Reexamination Certificate
active
06195502
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates generally to record media for recording video signals and, more particularly, to record media for use with playback apparatus to produce stop-motion video displays.
Record media of this particular type have typically been in the form of record discs and have recorded composite signals that contain both a video signal and an audio signal, simultaneously. The composite signal is normally recorded in a succession of substantially circular and concentrically arranged recording tracks on the disc, with each successive frame of the signal being recorded on a separate track. Stop-motion of a selected video frame is normally accomplished by repeatedly scanning a single track. Since the corresponding audio signal would be meaningless if it, too, were repeated successively, it is normally squelched during this stop-motion playback.
One technique for providing playback of an audio signal while displaying a stop-notion video frame is to record the same video signal on a number of successive recording tracks, but with a unique portion of the audio signal recorded on each track. In this manner, the composite signal can be played back from the record disc in a conventional manner, and the video display will appear to be in stop-motion, but will be accompanied by a normal audio signal. While this technique may prove satisfactory in some situations, it can sometimes be unduly wasteful of recording space on the record disc.
It will thus be appreciated that there is a need for a video recording medium, along with apparatus for formatting a composite signal for recording on the medium and apparatus for suitably processing the signal recovered from the medium, wherein the video signal can be played back in a stop-motion fashion, with an accompanying audio signal, while using a minimum number of recording tracks on the medium. The present invention fulfills this need.
SUMMARY OF THE INVENTION
The present invention is embodied in a record medium for recording a specially-formatted composite signal that includes both a video signal, representative of a video frame, and a corresponding audio signal, wherein the medium is suitable for use with special playback apparatus for displaying the video frame, in a repeated fashion, while accompanied by a playback of a corresponding analog audio signal. In accordance with the invention, the audio signal is recorded in a special time-compressed format on a first portion of the medium, and the video signal is recorded on a second portion of the medium, whereby apparatus for playing the record medium can operate to re-create the analog audio signal corresponding to the time-compressed audio signal, while the video frame is being displayed, repeatedly, a prescribed number of times.
More particularly, a record medium in accordance with the present invention is in the form of a record disc having a succession of substantially circular and concentrically arranged recording tracks. The special time-compressed audio signal is recorded on alternate tracks on the disc, and the corresponding frames of the video signal are recorded on the tracks therebetween. The audio signal is preferably in a digital format, and is arranged in a succession of bit packets that are interleaved with conventional periodic video synchronization signals, whereby the recorded audio signal has the appearance of a conventional video signal with a luminance value that alternates between white and black levels. Additionally, the bit rate of the successive bit packets in the recorded digital audio signal is synchronized with the frequency of periodic chrominance burst signals included in the video synchronization signals, thereby further simplifying detection during playback.
The recorded disc is suitable for playback in a slow-motion fashion, wherein each of the recorded video frames is displayed, in a repeated fashion, a prescribed number of times, while, simultaneously, the corresponding digital audio signal is converted back to an original analog format, for playback at its original speed. Thus, a stop-motion video sequence can be achieved, with accompanying audio, while utilizing a minimum number of recording tracks.
Apparatus in accordance with the present invention, for recording the composite signal on the video record disc, includes digitizing means for converting a conventional analog audio signal into a corresponding digital audio signal having a relatively low bit rate, for clocking into a digital memory device. The apparatus further includes means for clocking the digital data out of the memory to produce a succession of bit packets having a relatively high bit rate, along with means for combining the bit packets with periodic synchronization signals to produce the special digital audio signal for recording on the disc. As a result of the increase in bit rate, the original audio information is substantially compressed in time, permitted approximately 13 seconds of audio information to be recorded on a single track.
The digitizing means preferably comprises a delta modulator, whereby special digital synchronization signals for the digital data are not required Also, the digital audio signal is low-pass filtered to limit its bandwidth to approximately that of a conventional video signal. This specially-formatted digital audio signal is then combined, in a serial fashion, with a corresponding video signal, and coupled to a conventional disc mastering machine for recording on the disc.
Apparatus for playing back a video record disc in accordance with the present invention includes means for separating the successive packets of the high bit rate digital audio signal interleaved with the periodic video synchronization signals, along with means for loading the separated packets of data into a digital memory device. The apparatus further includes means for clocking the digital data out of the memory device at a relatively slow bit rate, corresponding to its original non-compressed rate, and means for converting this relatively slow digital signal into a corresponding analog audio signal for playback at its original speed.
Simultaneous with the playback of each audio signal segment, the corresponding video signal, recorded on the adjacent track on the disc, is displayed, in a repeated fashion, a prescribed number of times. Each such video frame can include a special code in its vertical interval, indicating the number of times it is to be scanned by the playback apparatus. Alter this prescribed number of scans, the apparatus performs the same procedure for the next audio/video recording track pair.
REFERENCES:
patent: 3579122 (1971-05-01), Paine et al.
patent: 3789137 (1974-01-01), Newell
patent: 3878560 (1975-04-01), Ramage
patent: 3909512 (1975-09-01), Omori et al.
patent: 3924062 (1975-12-01), Broadbent
patent: 3939302 (1976-02-01), Kihara
patent: 4030129 (1977-06-01), Whitlock
patent: 4044379 (1977-08-01), Halter
patent: 4065794 (1977-12-01), Shutterly
patent: 4065795 (1977-12-01), Shutterly
patent: 4138694 (1979-02-01), Doi et al.
patent: 4141039 (1979-02-01), Yamamoto
patent: 4227213 (1980-10-01), Isobe
patent: 4286290 (1981-08-01), Pyles et al.
patent: 4332022 (1982-05-01), Ceshkovsky et al.
patent: 4583131 (1986-04-01), Dakin
patent: 4613912 (1986-09-01), Shibata et al.
patent: 4809118 (1989-02-01), Nakagawa et al.
patent: 4959734 (1990-09-01), Foster
patent: 2849791 (1979-05-01), None
Intellectual Property Law Citations, First Shepard's Volume through Jun. 1997 Supplement, 1997.
Kenny, “Special Purpose Applications of the Optical Video Disc System,” pp. 327-337 IEEE Transactions on Consumer Electronics/76.
Ludewan, “Extended Audio-Video System” IBM Technical Disclosure Bulletin vol. 19 No. 5 Oct. 1976.
Ludeman, Extended Audio-Video System, IBM Tech Disc Bulletin, vol. 19, No. 5, Oct. 1976, pp. 1546-47.
Discovision Associates
Masaki Keiji
Tran Thai
Wenskay Donald
Wong Steve A.
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