Patent ID: 7283174

Claim:
A video signal processing apparatus comprising: video source determining means for inputting a video signal and a delayed video signal, produced by delaying said video signal by an equivalent of two fields, and determining whether a video source of the video signal is a film source; and line doubling means for receiving an input of three video signals, generating a field in which the number of scan lines is increased, and outputting a video signal according to a scanning method out of interlaced scanning and progressive scanning, wherein said video source determining means includes: calculating means for calculating a degree of similarity or a degree of difference between a picture of a field provided by the video signal and a picture of a field provided by the delayed video signal; threshold setting means for outputting a threshold for determining whether the pictures of each field match; comparison means for comparing a calculated value relating to the degree of similarity or the degree of difference outputted from said calculating means and the threshold outputted from said threshold setting means and determining whether the pictures of each field match; signal pattern detecting means for detecting a signal pattern for a compare signal outputted from said comparison means and determining whether the video source is a film source; and state transition means for specifying a state that changes in accordance with a determination result for the video source, the state indicating at least when the video source has been determined to be a film source and when the video source has been determined to not be a film source; wherein the threshold setting means outputs different thresholds based on the state specified by the state transition means.