Image enlargement device, image enlargement program, memory medium on which an image enlargement program is stored, and display device

An image enlargement device comprising:

• an image enlargement filter that generates a first enlarged image of an input image;
• a first wavelet transform portion that generates, by applying wavelet transform to the first enlarged image, a first sub-band component indicating an image obtained by extracting a low frequency component in a horizontal direction of the first enlarged image and a low frequency component in a vertical direction of the first enlarged image;
• a second sub-band component indicating an image obtained by extracting a high frequency component in a horizontal direction of the first enlarged image;
• a third sub-band component indicating an image obtained by extracting a high frequency component in a vertical direction of the first enlarged image;
• and a fourth sub-band component indicating an image obtained by extracting a high frequency component in a horizontal direction of the first enlarged image and a high frequency component in a vertical direction of the first enlarged image;
• a second wavelet transform portion that generates, by applying the wavelet transform to the first enlarged image, a fifth sub-band component indicating an image obtained by extracting a low frequency component in a horizontal direction of the first enlarged image and a low frequency component in a vertical direction of the first enlarged image;
• a sixth sub-band component indicating an image obtained by extracting a high frequency component in a horizontal direction of the first enlarged image;
• a seventh sub-band component indicating an image obtained by extracting a high frequency component in a vertical direction of the first enlarged image;
• and an eighth sub-band component indicating an image obtained by extracting a high frequency component in a horizontal direction of the first enlarged image and a high frequency component in a vertical direction of the first enlarged image;
• a first inverse wavelet transform portion that regards a predetermined sub-band component and the second sub-band component, the third sub-band component, and the fourth sub-band component, which are output from the first wavelet transform portion, as a wavelet transform image;
• performs inverse wavelet transform, thereby generating a first edge signal;
• a second inverse wavelet transform portion that regards the predetermined sub-band component and the sixth sub-band component, the seventh sub-band component, and the eighth sub-band component, which are output from the second wavelet transform portion, as the wavelet transform image;
• performs the inverse wavelet transform, thereby generating a second edge signal;
• an image enlargement portion that generates a second enlarged image;
• and
• an accentuation process portion that applies an accentuation process to the second enlarged image by using the first edge signal and the second edge signal;
• wherein
• the first wavelet transform portion and the second wavelet transform portion use wavelet transforms different from each other;
• and
• the first inverse wavelet transform portion and the second inverse wavelet transform portion use inverse wavelet transforms different from each other.