| 摘要 |
PURPOSE:To expand the equivalent band of a color signal by generating a coefficient changing in response to a production form of a high frequency signal component of a luminance signal and a color difference signal, generating a component resulting from weighting the coefficient onto the color difference signal and multiplexing the component onto the color difference signal. CONSTITUTION:One of color difference signals I, Q is inputted to LPF circuits 1, 2, in which band limit is implemented to generate a Q signal of 0-0.5MHz and an I signal of 0-1.5MHz. Moreover, a luminance signal Y and the other of the color difference signals I, Q are respectively inputted to a BPF circuit 3 and the frequency component of 0.5-1.5MHz is extracted as high frequency signal components YH, IH, QH and inputted to a discrimination circuit 4 to decide a coefficient K weighted to a high frequency signal component IH depending on a form of production of the signal level. Then the signal K.IH generated by a coefficient multiplier circuit 5 is added to the color difference I signal subject to band limit by an LPF circuit 2 at an adder 6 and the result is inputted to the encoder circuit 7 as a color difference signal I. |
