High-definition television signal processing system for transmitting and receiving a television signal in a manner compatible with the present system

In an apparatus for converting an interlace scanning signal, including a main signal of M scanning lines per frame for a vertically central portion of a screen and an augment signal of not more than (N-M) scanning lines per frame for upper and lower side portions of the screen, into a progressive scanning signal of N scanning lines per frame, a television signal receiving apparatus comprising:

• means for obtaining a first progressive scanning signal of the M per frame scanning lines by superposing fields of the interlace scanning signal;
• first converting means for converting the augment signal of not more than the (N-M) lines per frame into the signal of the M scanning lines per frame;
• removing means for frequency-shifting a signal output from said first converting means to a vertical high-frequency region, and adding the shifted signal to the first progressive scanning signal, thereby removing a mixed non-required moving image signal;
• and
• means for converting a signal obtained by said removing means into a signal of the N scanning lines, thereby converting the signal into the progressive scanning signal of the N scanning lines per frame having the same frame frequency as that of a signal on a transmission side.

A television signal transmission processing apparatus for transmitting a main signal of M (M:

• a natural number) scanning lines per frame for a vertically central portion of a screen, the main signal being obtained by converting a sequential scanning signal having N (N:
• a natural number) scanning lines per frame into a television signal having the M scanning lines, and for transmitting an augment signal of (N-M) scanning lines per frame for upper and lower side portions of the screen, comprising:
• means for obtaining an interframe sum output and an interframe difference output from the progressive scanning signals comprising the N scanning lines per frame by interframe sum average calculation and by interframe difference average calculation, respectively, in units of two frames;
• first band-limiting means for limiting a spatial frequency band of the interframe sum output;
• second band-limiting means for limiting a spatial frequency band of the interframe difference output with a characteristic different from that of said fist band limiting means;
• first scanning line converting means for converting an output from said first band-limiting means into the M scanning lines per frame;
• second scanning line converting means for converting an output from said second band-limiting means into the M scanning lines per frame;
• means for causing sum arithmetic means to receive outputs from said first and second scanning line converting means to generate a first frame signal in units of two frames;
• means for causing difference arithmetic means to receive the outputs from said first and second scanning line converting means to generate a second frame signal in units of two frames;
• means for transmitting the first and second frame signals as an interlace scanning signal of M scanning lines per frame for the central portion of the screen;
• third scanning line converting means for converting an output from said second band-limiting means into the (N-M) scanning lines per frame;
• and
• means for transmitting an output from said third scanning line converting means as the augment signal of the (N-M) interlace scanning lines per frame for the upper and lower side portions of the screen.

In an apparatus for converting an interlace scanning signal, including a main signal of M scanning lines per frame for a vertically central portion of a screen and an augment signal of not more than (N-M) scanning lines per frame for upper and lower side portions of the screen, into a progressive scanning signal of N scanning lines per frame, a television signal receiving apparatus comprising:

• means for obtaining a first progressive scanning signal of the M per frame scanning lines by superposing fields of the interlace scanning signal;
• first scanning line converting means for converting the signal of not more than the (N-M) scanning lines per frame into a signal of the M scanning lines per frame;
• means for frequency-shifting the signal output from said first scanning line converting means to a vertical high-frequency region, and adding the shifted signal to the first progressive scanning signal, thereby removing a mixed non-required moving image signal;
• second scanning line converting means for converting a signal obtained by said removing means into a signal of the N scanning lines;
• third scanning line converting means for converting the signal of not more than the (N-M) scanning lines per frame into a signal of the N scanning lines;
• and
• means for frequency-shifting the signal obtained by said third scanning line converting means to a temporary high-frequency region and adding the shifted signal to the signal obtained by said second scanning line converting means, thereby converting the signal to the progressive scanning signal of the N scanning lines per frame having the same frame frequency as that of an original signal on the transmission side.

In an apparatus for converting an interlace scanning signal, including a main signal of M scanning lines per frame for a vertically central portion of a screen and an augment signal of not more than (N-M) scanning lines per frame for upper and lower side portions of the screen, into a progressive scanning signal of N scanning lines per frame, a television signal receiving apparatus comprising:

• means for obtaining a first progressive scanning signal of the M per frame scanning lines by superposing fields of the interlace scanning signal;
• first scanning line converting means for converting the signal of not more than the (N-M) scanning lines per frame into a signal of the M scanning lines per frame;
• means for frequency-shifting the signal output from said first scanning line converting means to a vertical high-frequency region, and adding the shifted signal to the first progressive scanning signal, thereby removing a mixed non-required moving image signal;
• second scanning line converting means for converting a signal obtained by said removing means into a signal of the N scanning lines;
• third scanning line converting means for converting the signal of not more than the (N-M) lines per frame into a signal of the N scanning lines;
• first adding means for adding a non-inverted output of the signal obtained by said third scanning line converting means to the signal obtained by said second scanning line converting means;
• second adding means for adding an inverted output of the signal obtained by said third scanning line converting means to the signal obtained by said second scanning line converting means;
• and
• means for converting signals obtained by said first and second adding means into a double-speed progressive scanning signal of the N scanning lines per frame.