Patent ID: 7098964

Claim:
Method for slope enhancement of signal transitions in a television picture which is formed from at least one picture signal s(t), the method comprising: generating from the picture signal s(t) a discrete picture signal s(k) having a sequence of picture signal values; filtering the discrete picture signal s(k) using a peaking filter H[z] that provides filtered signal f(k), the filtered signal f(k) having for picture signal values s(x), corresponding signal values f(x); generating a modified picture signal m(k) having a sequence of signal values in response to the picture signal s(k) and the filtered signal f(k) where the step of generating for each signal value m(x) of the modified picture signal m(k) includes selecting a signal value s(x) of the picture signal s(k); for the selected signal value s(x) determining a first local extreme el(x) from a sub-sequence of the picture signal s(k) immediately preceding the selected signal value s(x), and determining a second local extreme er(x) from a subsequence of the picture signal s(k) immediately subsequent to the selected signal value s(x); and selecting the modified picture signal value (m(x)) from one of either the selected signal value s(x), the first local extreme el(x), the second local extreme er(x) or the filtered signal f(k).