Enhancing the tonal and spatial characteristics of digital images using selective spatial filters

A method of enhancing the tonal and spatial characteristics of a digital image, comprising the steps of:

• a) receiving a source digital image in an RGB representation having a red, green and blue digital image channel each digital image channel including a plurality of pixels;
• b) producing a tone scale function that can be used to enhance the tonal characteristics of the source digital image;
• c) classifying the tone scale function into one of two or more categories, wherein the classification categories include expansive and compressive;
• d) transforming the source digital image into a luminance-chrominance representation;
• and
• e) using a first spatial filter, the tone scale function, and the luminance-chrominance representation of the source digital image to produce an enhanced digital image when the tone scale function has been classified as compressive;
• and using a second spatial filter, the tone scale function, and the source digital image to produce the enhanced digital image when the tone scale function has classified as expansive.

A method of enhancing the tonal and spatial characteristics of a digital image, comprising the steps of:

• a) receiving a source digital image including digital image channels each having a plurality of pixels;
• b) producing a tone scale function that can be used to enhance the tonal characteristics of the source digital image;
• c) classifying the tone scale function into one of two or more categories, wherein the classification categories include expansive and compressive;
• and
• d) using the tone scale function, the source digital image, and a first spatial filter to produce an enhanced digital image when the tone scale function has been classified as compressive, and using the tone scale function, the source digital image, and a second noise reduction spatial filter to produce an enhanced digital image when the tone scale function has been classified as expansive.

A method of enhancing the tonal and spatial characteristics of a digital image, comprising the steps of:

• a) receiving a source digital image including a plurality of pixels;
• b) producing a tone scale function that can be used to enhance the tonal characteristics of the source digital image;
• c) classifying the tone scale function into one of two or more categories resulting in an assigned classification category;
• and
• d) using assigned classification category to select one of a plurality of spatial filter;
• and
• e) using the selected spatial filter, the tone scale function, and the source digital image to produce an enhanced digital image.

A method of enhancing the tonal and spatial characteristics of a digital image, comprising the steps of:

• a) receiving a source digital image including a plurality of pixels;
• b) producing a tone scale function that can be used to enhance the tonal characteristics of the source digital image;
• c) analyzing the tone scale function and selecting a spatial filter from a plurality of spatial filters in accordance with the analyzed tone scale function;
• and
• d) using the selected spatial filter, the tone scale function, and the source digital image to produce an enhanced digital image.