Image conversion method and image conversion apparatus

An image conversion method for converting an image format of an input image into a different image format of an output image, said method comprising the steps of:

• assuming that the input image is a first interlaced scanning image having a field frequency of m (m:
• integer not less than 2) fields/sec, and performing progressive scanning conversion for converting the first interlaced scanning image into a first progressive scanning image having a frame frequency of m frames/sec;
• and
• performing frame frequency conversion for converting the first progressive scanning image into a second progressive scanning image having a frame frequency of n (n:
• integer not less than 1) frames/sec, by repeating or thinning the first progressive scanning image in frame units, and outputting the second progressive scanning image.

An image conversion method for converting an image format of an input image into a different image format of an output image, said method comprising the steps of:

• assuming that the input image is a first interlaced scanning image having a field frequency of m (m:
• integer not less than 2) fields/sec, and performing progressive scanning conversion for converting the first interlaced scanning image into a first progressive scanning image having a frame frequency of m frames/sec;
• performing frame frequency conversion for converting the first progressive scanning image into a second progressive scanning image having a frame frequency of n (n:
• integer not less than 2) frames/sec, by repeating or thinning the first progressive scanning image in frame units;
• performing interlaced scanning conversion for converting the second progressive scanning image into a second interlaced scanning image having a field frequency of n fields/sec;
• and
• outputting the second progressive scanning image and the second interlaced scanning image simultaneously.

An image conversion method for converting an image format of an input image into a different image format of an output image, said method comprising the steps of:

• assuming that the input image is a first interlaced scanning image having a field frequency of m (m:
• integer not less than 2) fields/sec and an image size of horizontal h pixels×vertical v pixels, and performing progressive scanning conversion for converting the first interlaced scanning image into a first progressive scanning image having a frame frequency of m frames/sec and an image size of horizontal i pixels×vertical w pixels;
• performing frame frequency conversion for converting the first progressive scanning image into a second progressive scanning image having a frame frequency of n (n:
• integer not less than 1) frames/sec and an image size of horizontal i pixels×vertical w pixels, by thinning the first progressive scanning image in frame units;
• and
• performing interlaced scanning conversion for converting the second progressive scanning image into a second interlaced scanning image having a field frequency of 2 n fields/sec and an image size of horizontal i pixels×vertical w pixels.

An image conversion method for converting an image format of an input image into a different image format of an output image, said method comprising the steps of:

• assuming that the input image is a first interlaced scanning image having a field frequency of m (m:
• integer not less than 2) fields/sec and an image size of horizontal h pixels×vertical v pixels, and performing progressive scanning conversion for converting the first interlaced scanning image into a first progressive scanning image having a frame frequency of m frames/sec and an image size of horizontal i pixels×vertical w pixels;
• and
• performing frame frequency conversion for converting the first progressive scanning image into a second progressive scanning image having a frame frequency of n (n:
• integer not less than 1) frames/sec and an image size of horizontal i pixels×vertical w pixels, by repeating or thinning the first progressive scanning image in frame units, and outputting the second progressive scanning image.

An image conversion method for converting an image format of an input image into a different image format of an output image, said method comprising the steps of:

• assuming that the input image is a first interlaced scanning image having a field frequency of m (m:
• integer not less than 2) fields/sec and an image size of horizontal h pixels X vertical v pixels, and performing progressive scanning conversion for converting the first interlaced scanning image into a first progressive scanning image having a frame frequency of m frames/sec and an image size of horizontal i pixels×vertical w pixels;
• performing frame frequency conversion for converting the first progressive scanning image into a second progressive scanning image having a frame frequency of n (n:
• integer not less than 2) frames/sec and an image size of horizontal i pixels×vertical w pixels, by repeating or thinning the first progressive scanning image in frame units;
• performing interlaced scanning conversion for converting the second progressive scanning image into a second interlaced scanning image having a field frequency of n fields/sec and an image size of horizontal i pixels×vertical w pixels;
• and
• outputting the second progressive scanning image and the second interlaced scanning image simultaneously.

An image conversion apparatus for converting an image format of an input image into a different image format of an output image, said apparatus comprising:

• a progressive scanning converter for receiving the input image as a first interlaced scanning image having a field frequency of m (m:
• integer not less than 2) fields/sec, and converting the first interlaced scanning image into a first progressive scanning image having a frame frequency of m frames/sec;
• a frame frequency converter for converting the first progressive scanning image into a second progressive scanning image having a frame frequency of n (n:
• integer not less than 1) frames/second, by thinning the first progressive scanning image in frame units;
• and
• an interlaced scanning converter for converting the second progressive scanning image into a second interlaced scanning image having a field frequency of 2 n fields/sec, and outputting the second interlaced scanning image.

An image conversion apparatus for converting an image format of an input image into a different image format of an output image, said apparatus comprising:

• a progressive scanning converter for receiving the input image as a first interlaced scanning image having a field frequency of m (m:
• integer not less than 2) fields/sec, and converting the first interlaced scanning image into a first progressive scanning image having a frame frequency of m frames/sec;
• and
• a frame frequency converter for converting the first progressive scanning image into a second progressive scanning image having a frame frequency of n (n:
• integer not less than 1) frames/sec, by repeating or thinning the first progressive scanning image in frame units, and outputting the second progressive scanning image.

An image conversion apparatus for converting an image format of an input image into a different image format of an output image, said apparatus comprising:

• a progressive scanning converter for receiving the input image as a first interlaced scanning image having a field frequency of m (m:
• integer not less than 2) fields/sec, and converting the first interlaced scanning image into a first progressive scanning image having a frame frequency of m frames/sec;
• a frame frequency converter for converting the first progressive scanning image into a second progressive scanning image having a frame frequency of n (n:
• integer not less than 2) frames/sec, by repeating or thinning the first progressive scanning image in frame units;
• and
• an interlaced scanning converter for converting the second progressive scanning image into a second interlaced scanning image having a field frequency of n fields/sec, and outputting the second interlaced scanning image simultaneously with the second progressive scanning image.

An image conversion apparatus for converting an image format of an input image into a different image format of an output image, said apparatus comprising:

• a progressive scanning converter for receiving the input image as a first interlaced scanning image having a field frequency of m (m:
• integer not less than 2) fields/sec and an image size of horizontal h pixels×vertical v pixels, and converting the first interlaced scanning image into a first progressive scanning image having a frame frequency of m frames/sec and an image size of horizontal i pixels×vertical w pixels;
• a frame frequency converter for converting the first progressive scanning image into a second progressive scanning image having a frame frequency of n (n:
• integer not less than 1) frames/sec and an image size of horizontal i pixels×vertical w pixels, by thinning the first progressive scanning image in frame units;
• and
• an interlaced scanning converter for converting the second progressive scanning image into a second interlaced scanning image having a field frequency of 2 n fields/sec and an image size of horizontal i pixels×vertical w pixels, and outputting the second interlaced scanning image.

An image conversion apparatus for converting an image format of an input image into a different image format of an output image, said apparatus comprising:

• a progressive scanning converter for receiving the input image as a first interlaced scanning image having a field frequency of m (m:
• integer not less than 2) fields/sec and an image size of horizontal h pixels×vertical v pixels, and converting the first interlaced scanning image into a first progressive scanning image having a frame frequency of m frames/sec and an image size of horizontal i pixels×vertical w pixels;
• and
• a frame frequency converter for converting the first progressive scanning image into a second progressive scanning image having a frame frequency of n (n:
• integer not less than 1) frames/sec and an image size of horizontal i pixels×vertical w pixels, by repeating or thinning the first progressive scanning image in frame units, and outputting the second progressive scanning image.

An image conversion apparatus for converting an image format of an input image into a different image format of an output image, said apparatus comprising:

• a progressive scanning converter for receiving the input image as a first interlaced scanning image having a field frequency of m (m:
• integer not less than 2) fields/sec and an image size of horizontal h pixels×vertical v pixels, and converting the first interlaced scanning image into a first progressive scanning image having a frame frequency of m frames/sec and an image size of horizontal i pixels×vertical w pixels;
• a frame frequency converter for converting the first progressive scanning image into a second progressive scanning image having a frame frequency of n (n:
• integer not less than 2) frames/sec and a screen size of horizontal i pixels×vertical w pixels, by repeating or thinning the first progressive scanning image in frame units;
• and
• an interlaced scanning converter for converting the second progressive scanning image into a second interlaced scanning image having a field frequency of n fields/sec and an image size of horizontal i pixels×vertical w pixels, and outputting the second interlaced scanning image simultaneously with the second progressive scanning image.

An image conversion apparatus for converting an image format of an input image into a different image format of an output image, said apparatus comprising:

• a judgement means for judging the image format of the input image;
• a first image conversion means for, when the image format of the input image is a first image format, converting it into a second image format and outputting the converted image;
• a second image conversion means for, when the image format of the input image is the second image format, converting it into the first image format and outputting the converted image;
• and
• a switching means for selecting either the first image conversion means or the second image conversion means on the basis of the result of the judgement by the judgement means.