Abstract: An HDTV signal is converted to an NTSC bandwidth by analog encoding changing its conventional serial element format to a parallel element format. The picture elements of several HDTV scan lines are combined by fractal scanning and all simultaneously expressed over the time period of one NTSC scan line as individual frequency components within a given spectrum every component maintaining a constant amplitude corresponding to its original modulation level. The procedure is repeated at the NTSC scan line rate. The encoder controls the number of individual frequency components to achieve an HDTV level of information transmission and the frequency spacing between the individual frequency components to effect a bandwidth compression to NTSC levels. A decoder changes the received parallel element format to a serial element format and uses fractal scanning to separate the combined lines for conventional presentation.

Abstract: A video signal having a given line scan rate is converted to a different line scan rate by analog encoding such that each scan line is divided into a finite number of picture elements and video information corresponding to each picture element is modulated onto one of a series of carrier frequencies for transmission in parallel form. An inexpensive decoder scans the encoded video signal to reconstruct an output video signal having a line scan rate related to the rate of repetition of the encoded video signal scanning cycle.