Video display apparatus with scan conversion and reversion and a video display method using scan conversion and reversion

A video display apparatus comprising:

• a conversion circuit receiving a first video signal of an interlaced scanning system or a progressive scanning system including a first number of scanning lines in each frame and having a first vertical scanning frequency and converting said first video signal to a second video signal of a progressive scanning system including a second number of scanning lines in each frame and having a second vertical scanning frequency, wherein said second vertical scanning frequency is even times said first vertical scanning frequency;
• a scanning line reversion circuit alternately reversing the time base of said second video signal output from said conversion circuit every scanning line and outputting processed said second video signal as a third video signal;
• a display part displaying said third video signal output from said scanning line reversion circuit by bidirectional scanning in synchronization with a vertical synchronizing signal and a horizontal synchronizing signal after conversion by said conversion circuit;
• and
• a second offset circuit displacing said vertical synchronizing signal so that a plurality of fields included in each frame keep interlaced relation.

A video display apparatus comprising:

• a conversion circuit receiving a first video signal of an interlaced scanning system or a progressive scanning system including a first number of scanning lines in each frame and having a first vertical scanning frequency and converting said first video signal to a second video signal of a progressive scanning system including a second number of scanning lines in each frame and having a second vertical scanning frequency, wherein said first video signal is of an interlaced scanning system, said first number is an odd number, said first vertical scanning frequency is even times said second vertical scanning frequency, and each frame includes a plurality of fields;
• a scanning line reversion circuit alternately reversing the time base of said second video signal output from said conversion circuit every scanning line and outputting processed said second video signal as a third video signal;
• a display part displaying said third video signal output from said scanning line reversion circuit by bidirectional scanning in synchronization with a vertical synchronizing signal and a horizontal synchronizing signal after conversion by said conversion circuit;
• and
• a third offset circuit displacing said vertical synchronizing signal so that said plurality of fields of each frame keep interlaced relation.

A video display method comprising steps of:

• receiving a first video signal of an interlaced scanning system or a progressive scanning system including a first number of scanning lines in each frame and having a first vertical scanning frequency and converting said first video signal to a second video signal of a progressive scanning system including a second number of scanning lines in each frame and having a second vertical scanning frequency, wherein said second vertical scanning frequency is equal to said first vertical scanning frequency;
• alternately reversing the time base of said second video signal every scanning line and outputting processed said second video signal as a third video signal;
• and
• displaying said third video signal by bidirectional scanning in synchronization with a vertical synchronizing signal and a horizontal synchronizing signal after conversion.

A video display method comprising steps of:

• receiving a first video signal of an interlaced scanning system or a progressive scanning system including a first number of scanning lines in each frame and having a first vertical scanning frequency and converting said first video signal to a second video signal of a progressive scanning system including a second number of scanning lines in each frame and having a second vertical scanning frequency, wherein said second vertical scanning frequency is even times said first vertical scanning frequency;
• alternately reversing the time base of said second video signal every scanning line and outputting processed said second video signal as a third video signal;
• displaying said third video signal by bidirectional scanning in synchronization with a vertical synchronizing signal and a horizontal synchronizing signal after conversion;
• and
• displacing said vertical synchronizing signal so that a plurality of fields included in each frame keep interlaced relation.

A video display method comprising steps of:

• receiving a first video signal of an interlaced scanning system or a progressive scanning system including a first number of scanning lines in each frame and having a first vertical scanning frequency and converting said first video signal to a second video signal of a progressive scanning system including a second number of scanning lines in each frame and having a second vertical scanning frequency, wherein said first video signal is of an interlaced scanning system, said first number is an odd number, said first vertical scanning frequency is even times said second vertical scanning frequency, and each frame includes a plurality of fields;
• alternately reversing the time base of said second video signal every scanning line and outputting processed said second video signal as a third video signal;
• displaying said third video signal by bidirectional scanning in synchronization with a vertical synchronizing signal and a horizontal synchronizing signal after conversion;
• and
• displacing said vertical synchronizing signal so that said plurality of fields of