Abstract: A still image transmitting system using a bandwidth compression method (MUSE) for transmitting a video image signal of a wideband used practically in the high definition television system (HDTV) employs a transmitting method such that the number of fields of transmitted image is increased to two times that in the conventional still image mode so that the resolution in the diagonal direction is improved without increasing the transmission bandwidth.

Abstract: A noise reducer of a signal receiving circuit system applying different manners of signal processing to moving video image and still video image regions includes a noise reduction circuit detecting a two-frame difference signal of a received video signal and deducting the two-frame difference signal from the received video signal thereby reducing remaining noise in the still video image region, in which the proportion of the two-frame difference signal to be deducted in the noise reduction circuit is controlled by the noise level of the received video signal and a signal obtained in accordance with a detected quantity of motion in the received video signal.

Abstract: A MUSE-format video signal decoder comprising a first frame memory supplied with an input digital video signal and having a delay time of 1-frame period; a 1-frame difference detector including a first interpolation filter supplied with the input digital video signal, a second interpolation filter supplied with the digital video signal from the first frame memory, a first subtracter for obtaining the difference between the outputs of the first filter and the first frame memory, and a second subtracter for obtaining the difference between the input digital video signal and the output of the second filter, wherein a 1-frame difference signal is produced in accordance with the outputs of the first and second subtracters; and a 2-frame difference detector including first and second bit compressors supplied with the outputs of the first and second subtracters respectively, a second frame memory having a delay time of 1-frame period and supplied with outputs of the first and second bit compressors, and an adder for

Abstract: A signal processing apparatus comprising a plurality of video signal correlation detecting devices for detecting the values of video signal correlations in a plurality of ways with respect to the displayed picture, and intermediate value selecting devices for selecting an intermediate value among the detected values of the plurality of video signal correlations, whereby a changing video signal is processed by utilizing a correlation of a proper way.

Abstract: A sulfur dioxide-containing gas, for example, one obtained by an SO.sub.x and NO.sub.x removing process using ammonia is treated by the use of a reaction apparatus comprising a reducing reaction portion and a composition controlling oxidation reaction portion, provided in the same reactor or reactors adjacent to each other, to convert the composition of the gas into one suitable for the Claus reaction.

Abstract: An SO.sub.2 -containing gas, in particular, pre-stage gas for the Claus reaction to recover sulfur can effectively be purified by removing NH.sub.3 contained therein using a TiO.sub.2 catalyst.

Abstract: A chrominance signal processing circuit having N (N.gtoreq.2) band-pass filters for dividing a chrominance signal into N regions and N signal processing circuits respectively having different noise eliminating characteristics from each other and each being connected in series to a different one of the N band-pass filters, and means for synthesizing the outputs from the N signal processing circuits to obtain a chrominance signal wherein noise and cross color interference are suppressed.

Abstract: A signal processing apparatus comprising a plurality of video signal correlation detecting means for detecting the values of video signal correlations in a plurality of ways with respect to the displayed picture, and intermediate value selecting means for selecting an intermediate value among the detected values of the plurality of video signal correlations, whereby a changing video signal is processed by utilizing a correlation of a proper way.

Abstract: A digital code reader reads the digital key code in a scrambled video signal. The key code represents the scheme used to scramble the signal before broadcasting and is used by the video receiver to unscramble the received signal. To prevent misreading of the key code due to interference such as ghost signals, the reader uses a predetermined property established for the broadcast signal. The change in that property caused by interference in the received signal is determined and a control signal is generated from that determination. A threshold signal is used to reproduce the key code from the received signal by comparison of the levels of the received signal with the level of the threshold signal. The level of the threshold signal is set by the control signal, which depends on the change detected in the predetermined property of the broadcast signal. Thus the level of the threshold signal can be set to enable the reproduced digital information to match the broadcast digital information.

Abstract: An AFT circuit for a television receiver automatically adjusts the frequency of a tuner local oscillator, not only on the basis of an error signal provided from an AFT discriminator, but also on the basis of horizontal synchronizing pulses contained in the video signal to which the receiver is tuned. A synch signal detector detects the presence or absence of the synchronizing pulses. A control circuit provides a control signal to the local oscillator in response to the AFT error signal when the latter is above or below a reference voltage such that the desired frequency is within an AFT capture range. However, when the AFT signal is at the reference voltage, the control circuit provides the control signal based on the presence or absence of the synchronizing pulses, such that when the pulses are present, the local oscillator frequency is raised, but when the pulses are absent, the local oscillator frequency is lowered. Then, when the AFT signal is present, the local oscillator is controlled thereby.