摘要:
Video signal processing circuitry for compensating a video signal having different average levels in alternate horizontal line intervals, such as in odd and even line intervals during a field or frame interval. A first average detector is operable during alternate ones of the line intervals, for example, during odd line intervals, for detecting the average level of the video signal in such alternate line intervals. A second average detector is operable during the remaining ones of the line intervals, for example, during the even line intervals, for detecting the average level of the video signal in such remaining line intervals. A compensating circuit is responsive to the difference between the detected average levels of the video signal in the alternate and remaining line intervals, respectively, for producing compensating signals. These compensating signals are combined with the video signal so as to minimize the difference between the average level of the video signal in successive line intervals.
摘要:
In an apparatus for reproducing video signals which are recorded as modulations of a carrier on a record medium, such as a magnetic tape, in successive, abutting parallel record tracks, with the signals being recorded in alternating tracks with different first and second azimuth angles, first and second magnetic heads are provided for sequentially scanning the tracks in which signals are recorded with the first and second azimuth angles, respectively, and the first and second magnetic heads having azimuth angles corresponding to the first and second azimuth angles of the respective tracks to be scanned thereby. Each of the magnetic heads is dimensioned and guided in the direction transverse to the direction along the respective track being scanned so as to overlap an adjacent track by a distance .DELTA.W=n.lambda./tan .theta.(n=1,2, . . .), in which .lambda. is the wavelength of the carrier as modulated by synchronizing signal portions of the video signals recorded in such adjacent track, and .theta. is the difference between the first and second azimuth angles of the heads. In this manner, cross-talk from the adjacent track is substantially attenuated.
摘要翻译:在用于再现被记录为诸如磁带的记录介质上的载体的调制的视频信号的装置中,在连续的邻接并行记录轨道中,信号被记录在具有不同的第一和第二方位角的交替轨迹中, 提供第一和第二磁头以分别以第一和第二方位角顺序地扫描记录有信号的轨道,并且第一和第二磁头具有对应于各个轨道的第一和第二方位角的方位角到 被扫描。 每个磁头的尺寸和横向于沿着被扫描的相应轨道的方向被引导,以便使相邻轨道重叠距离DELTA W =nλ/tanθ(n = 1,2,...)。 ),其中λ是通过使记录在这种相邻轨道中的视频信号的信号部分同步来调制的载波的波长,θ是磁头的第一和第二方位角之间的差。 以这种方式,来自相邻轨道的串扰实质上是衰减的。
摘要:
An anti-piracy signal generating circuit for generating anti-piracy signal components on a video signal reproduced by a first video unit, the signal components being interleaved to a frequency f.sub.H in the band of the video signal in accordance with the video signal components and a signal superimposing circuit for superimposing the anti-piracy signal components intermittenly on the luminance signal, first color difference signal, and second color difference signal.
摘要:
A recording and reproducing apparatus wherein the video signal is time base expanded and separated into two channels before being recorded with a two headed recorder on two separate channels of a magnetic medium and wherein during reproduction the two channels from the magnetic medium are supplied to a time base corrector which supplies an output to a channel mixing and time base compressor which converts the two channels into a single output signal. A burst generator inserts burst signals into the two channels before they are recorded.
摘要:
A magnetic recording and/or reproducing apparatus and methods thereof for a composite color TV (television) signal arranged such that a luminance signal and a high band component of a chrominance subcarrier signal of the composite color TV signal are frequency modulated, recorded and reproduced, while a low band component of the chrominance subcarrier signal is frequency down converted to a frequency at a band lower than that of the frequency modulated signal, thus improving resolution of the color signal component.
摘要:
Apparatus for recording and/or reproducing a SECAM composite color television signal in parallel tracks on a record medium. The luminance and chrominance components of the SECAM television signal are separated from each other, and then the luminance component is modulated to a higher frequency range while the chrominance component is frequency-converted to a lower frequency range. These frequency-modified components are recombined and recorded. In frequency-converting the chrominance component, first and second frequency-converting carrier signals are generated, and the phases of these frequency-converting signals are synchronized, or locked, to the incoming SECAM television signal so as to exhibit corresponding phase changes. When these frequency-converting signals are used to frequency-convert the chrominance component of the SECAM television signal, the resultant frequency-converted chrominance components are recorded in at least one track with a substantially constant phase and in the next adjacent track with a frequency-converted sub-carrier which differs from that of the said one track. The recorded frequency-converted sub-carrier frequencies in adjacent tracks are in frequency interleaved relation with respect to each other. In one embodiment of the recording apparatus, the frequencies of the frequency-converting signals differ from each other by n/4fh, wherein n is an integer (preferably 1) and fh is the horizontal line frequency of the SECAM television signal. In this embodiment, the phase of the recorded chrominance subcarrier is constant for all tracks.
摘要:
An apparatus for reproducing a video signal recorded in skewed parallel tracks on a magnetic tape compensates both for cross-track and along-track errors during reproduction at a tape speed different from the tape speed employed during recording by affixing reproducing heads to bi-morph leaves which are skewed with respect to the direction of rotation of a rotating drum to which they are attached. The skew has components in the along-track direction and the across-track direction such that unidirectional motions of the bi-morph leaves simultaneously correct for cross-track and along-track errors.
摘要:
A method and apparatus for recording in successive parallel tracks on a record medium a periodic information signal, such as a video signal having information contained in successive line intervals, a predetermined number of line intervals being included in a field interval and a predetermined number of field intervals being included in a frame interval. Alternate ones of the frame intervals are delayed by a time delay equal to an odd multiple (2n-1) of a line interval. The delayed and undelayed frame intervals are supplied, in sequence, to a recording transducer for recording in successive parallel tracks on the record medium. If the video signal is a SECAM color video signal, then the effect of delaying alternate frame intervals, such as the odd (or even) frame intervals is to align line intervals in adjacent tracks with information representing the same color.Also disclosed are a method and apparatus for reproducing the periodic information signal which had been recorded in the aforementioned manner. These recorded signals are reproduced from the successive parallel tracks to recover the delayed and undelayed frame intervals alternately. The undelayed frame intervals are delayed, during reproduction, by a time delay equal to the aforesaid odd multiple (2n-1) of a line interval, thereby recovering the periodic information signal which appears in successive frame intervals as being undelayed relative to each other. Thus, if, during recording, the odd frame intervals are delayed, then during reproduction, the even frame intervals are delayed so as to equalize the reproduced odd and even frames.
摘要:
A method of and apparatus for recording a video signal in successive parallel tracks on a record medium, and for reproducing the recorded signal. The video signal, which may be the luminance component of a composite color television signal, frequency modulates a carrier to produce a frequency modulated video signal. The phase of the frequency modulated video signal is selectively shifted in selected line intervals and is recorded in parallel tracks such that the phase difference between frequency modulated video signals in at least some adjacently recorded line intervals of successive tracks is an odd multiple of .pi.. In one embodiment, the difference between the phase of alternate line intervals which are recorded in one track and the phase of alternate line intervals which are recorded in the next adjacent track is equal to an odd multiple of .pi.. In accordance with another embodiment, the difference between the phases of successive line intervals which are recorded in the same track is equal to an odd multiple of .pi.. During reproducing, the successive tracks are scanned and the frequency modulated signals recorded therein are reproduced together with a crosstalk component which is picked up by the transducer from an adjacent track, the crosstalk components being out of phase with each other. The reproduced frequency modulated signal is demodulated so as to recover the original video signal and an additional component, the latter being due to the phase shifting of the frequency modulated signal. The additional component then is eliminated from the recorded video signal.
摘要:
In apparatus for recording, or otherwise transmitting, video or other information signals, and in which at least a portion of the signal to be recorded, for example, the luminance component of a color video signal, is frequency modulated and then passed through a filter for limiting the frequency band of the resulting frequency modulated component or signal which is recorded; a signal processor, such as, an automatic gain control or limiter, acts on the frequency modulated output of the filter to eliminate or compensate for amplitude variations that may occur therein by reason of the filter, for example, at portions of the signal where substantial pre-emphasis was applied.