 Video tape recorder for recording/reproducing two-channel component color video signals |
| An object of the present invention is to provide a two-channel video tape recorder capable of ... |
|
| Facsimile data processing apparatus |
| Accordingly, it is an object of the present invention to provide a facsimile data processing ... |
|
| Automatic radio frequency signal level control apparatus for a video cassette recorder |
| It is an object of the present invention to provide an automatic RF signal level control apparatus ... |
|
| Universal signal processor and method of processing |
| Generally speaking, in accordance with the invention, a method for decoding and reconstructing a ... |
|
| Method for preventing error speading while recording compressed image data |
| Accordingly, it is an object of the present invention to provide a compressed image data recording ... |
|
| Continuous speed control system for video tape recorder |
| OF THE ILLUSTRATED EMBODIMENT Video tape editing control systems for cassette helical scan video ... |
|
| Apparatus for threading magnetic tape from a single reel cartridge in a rotary head tape transport |
| According to the present invention, there is provided in a rotary head magnetic tape recorder, ... |
|
|
Digital pulse generator phase-locked to color television video signals and means and method for thereby compensating for tape velocity timing errors
| Details |
Inventors: Heitmann, Jurgen;
Assignee: Robert Bosch GmbH (Stuttgart, DE)
Primary Examiner: Envall, Jr.; Roy N.
Assistant Examiner: Nguyen; Huy
Attorney, Agent or Firm: Frishauf, Holtz, Goodman & Woodward
In playback scanning of oblique tracks the jumps of velocity errors in the transition from one head to another are found to be substantially constant, but the magnitude of the velocity error as a whole is subject to statistical fluctuation and the like. Within a track a velocity error determined for one line is used for correction in the following line, while for the first line the magnitude of a jump from a previous magnetic head changeover in the same sense is utilized. With the help of a value from the last line or next-to-last line of the earlier track, a correction value is provided for the first line of the after next track. A ramp signal is inserted in each horizontal blanking interval ahead of the color synchronization signals, raising the latter to the top of the ramp level. The inserted signals are digitized along with the video signal. Samples of the digital ramp signal which pass through a magnitude window (70-73), which is set for passage of not more than two samples in a narrow range symmetrical with respect to the ramp midpoint, address a PROM which converts those magnitudes into timing error values of the pulse generator which provides sampling rate pulses for the converter that digitizes the video signal. The timing error values are used to correct the phase of that pulse generator. |
|
DETAILED DESCRIPTION What is claimed is: 1.
Method of compensating velocity errors in color television signals reproduced from oblique recording tracks on a magnetic tape, comprising, during reproduction of said signals, the steps of: producing, line by line, first error signals corresponding to velocity errors; utilizing each said first error signals produced with respect to one television line for compensation of the velocity error of the next line of the same track, and producing a second error signal at the beginning of every said oblique track from the difference between a selected pair of previously produced first error signals and using each said second error signal for compensating the velocity error of the first line of the next track following said every oblique track, said pair of selected first error signals consisting of a first error signal produced with respect to the first line of a track and a first error signal produced with respect to one of the two last lines of a track.
2.
Method of compensating velocity errors in color television signals reproduced form oblique recording tracks on a magnetic tape, comprising, during reproduction of said signals, the steps of: producing, line by line, first error signals corresponding to velocity errors; utilizing each said first error signal produced with respect to one television line for compensation of the velocity error of the next line of the same track, and producing a second error signal at the beginning of every said oblique track from the difference between a selected pair of previously produced first error signals and using each said second error signal for compensating the velocity error of the first line of the after-next track following said every oblique track, said pair of selected first error signals consisting of a first error signal produced with respect to the first line of a track and a first error signal produced with respect to one of the two last lines of a track.
3.
Method according to claim 1, wherein said second error signals are produced by forming the difference between a said first error signal produced with respect to the first line of a track and a said first error signal produced with respect to the last line of the last previous track thereto
|
|
TV Signal 
