US 5,327,235 A · Video conversions of video signal formats

Abstract

A digital video signal is real-time converted from a high definition format (such as 1250 lines, 50 field/s, 2:1 interlace, with a 16:9 aspect ratio) to a conventional definition format (such as 525 lines, 60 field/s, 2:1 interlace, with a 4:3 aspect ratio) by compressing the image so that the active area extends across only part of an intermediate field/frame; by writing the pixels of the high definition fields to alternate field stores at the high definition format pixel rate; and by forming the output frames in the conventional definition format by reading, at the conventional definition pixel rate, pixels of at least part of the active portion from the field store which is not being written. Alternatively, a conventional definition format signal is converted to a high definition format by placing each conventional definition field in a portion of a high definition field and then expanding that portion substantially to fill the high definition field. In order to deal with a change in field rate between the input and output video, a standards converter is included in the high definition part of the arrangement.

Claims20

Dependent claims

An apparatus for up-converting a digital video signal from a first format having a first field/frame rate to a second higher-definition format having a second different field/frame rate, comprising:

storage means which can store input fields/frames of pixel data in the first format at said first field/frame rate;
storage control means for controlling said storage means to output the stored pixel data together with dummy data at said first field/frame rate as intermediate fields/frames in a third format having higher definition than said first format, such that the pixel data occupies a continuous active portion of each intermediate field/frame and the dummy data occupies the remainder of that intermediate field or frame;
and
means for processing said intermediate fields/frames by expanding said active portions thereof in vertical and horizonal directions and changing the field/frame rate thereof to said second field/frame rate to produce output fields/frames in said second format such that the pixel data extends across substantially the whole of said output fields/frames in at least one of the vertical and horizontal directions.

1 more element

An apparatus for down-converting a digital video signal from a first format having a first field/frame rate to a second lower-definition format having a second different field/frame rate, comprising:

means for processing the input fields/frames by compressing active portions thereof in vertical and horizonal directions and changing the field/frame rate thereof to said second field/frame rate to produce intermediate fields/frames in a third format having a higher definition than said second format in which said active portions occupy only part of said fields/frames;
storage means which receives said intermediate fields/frames of pixel data in said third format at said second field/frame rate;
storage control means for controlling said storage means to store at least part of said active portion of each intermediate field/frame and to output the stored pixel data in said second format at said second field/frame rate, such that the pixel data of said active portions extends across substantially the whole of the output fields/frames in at least one of the vertical and horizontal directions.

Dependencies are inferred from the claim text.

Video conversions of video signal formats

Life of this patent

Video conversions of video signal formats

Life of this patent

Abstract

Claims20