Video processing in which high frequency luminance components are folded into a mid-band spectrum

A record medium containing stored information representing scanning lines of preprocessed video wherein the medium has been configured by a method comprising the steps of:

• comb filter preprocessing of original full bandwidth video information to establish and promote spectral gaps in a mid-frequency region of the video luminance signal to provide a combed luminance signal,
• folding over high frequency components of the combined luminance signal about a predetermined fold over clock frequency into mid-frequency spectral gaps promoted by the step of comb filter preprocessing of the original full bandwidth video information to generate folded bandwidth luminance signal,
• low pass filtering the folded bandwidth luminance signal so that a resultant filtered/folded bandwidth luminance signal is contained in a spectrum not substantially greater than one half the predetermined fold over clock frequency, and
• recording the resultant filtered/folded bandwidth luminance signal onto said record medium.

Apparatus for processing incoming scanning lines of quadrature modulated color subcarrier television within a video recording and playback machine, the apparatus including a preprocessor in a record path within the machine and a postprocessor within the playback path within the machine,

• the preprocessor including preprocessor bidimensional comb filter means for comb filter processing in the temporal and spatial domains the incoming scanning lines simultaneously for separating chrominance and luminance components and for assuring the presence of spectral gaps between energy groups in the spectrum of the combed luminance component, fold over means for folding over a high frequency luminance spectral region about a predetermined folding frequency in order to insert aliases of the high frequency spectral region into said spectral gaps in a mid-frequency region of said luminance component to create a folded spectrum, low pass filter means for low pass filtering said folded spectrum to limit it to a predetermined bandwidth not substantially greater than one half the predetermined folding frequency, chroma color-under processing means for creating a chroma carrier modulated with the comb filter separated chrominance component at a predetermined low frequency, frequency modulator means for modulating the low pass filtered folded spectrum upon a luminance carrier located above the chroma carrier, and preprocessor combining means for combining said chroma carrier and said luminance carrier into a composite signal for recording onto a storage medium used in conjunction with said video recording and playback machine;
• the postprocessor including spectrum splitting means for separating said chroma carrier and said luminance carrier, FM demodulator means for demodulating said luminance carrier, color-under playback processing means for recovering said quadrature modulated chrominance component from said chroma carrier, unfolding means connected to the FM demodulator means for unfolding the folded spectrum luminance component to create a plurality of aliases, postprocessor bidimensional comb filter means for comb filter processing in the temporal and spatial domains the unfolded luminance component to eliminate unwanted aliases in order to recover the original full bandwidth luminance component, and postprocessor combining means for combining the recovered quadrature modulated chrominance component and the recovered luminance component into a playback television signal.