Device and method for creating a saliency map of an image

• US 7,853,076 B2
• Filed: 12/14/2004
• Issued: 12/14/2010
• Est. Priority Date: 12/18/2003
• Status: Expired due to Fees

• Current Assignee: Interdigital Vc Holdings, Inc. (InterDigital, Inc.)
• Original Assignee: Thomson Licensing (Vantiva SA)
• Inventors: Francois, Edouard, Thoreau, Dominique, Le Meur, Olivier, Le Callet, Patrick, Barba, Dominique
• Primary Examiner(s): Couso; Jose L
• Application Number:
  US10/583,673
• Publication Number:
  US 20070116361A1
• Time in Patent Office: 2,191 Days
• Field of Search: 382/100, 382/103, 382/128, 382/154, 382/164, 382/166, 382/168, 382/170, 382/171, 382/173, 382/176, 382/181, 382/254, 382/282, 348/135, 348/139, 348154-155, 348/169, 375/240.08, 375/240.19
• US Class Current: 382/166
• CPC Class Codes: G06T 2207/10024 Color image
• CPC Class Codes: G06T 5/73 Deblurring; Sharpening
• CPC Class Codes: G06T 7/262 using transform domain methods, e.g. Fourier domain methods
• CPC Class Codes: G06V 10/451 with interaction between the filter responses, e.g. cortical complex cells
• CPC Class Codes: G06V 10/462 Salient features, e.g. scale invariant feature transforms [SIFT]
• CPC Class Codes: G06V 10/56 relating to colour

Abstract

The invention concerns a device and a method for creating a saliency map of an image. It comprises the steps of:

• • Projection of said image according to the luminance component and if said image is a color image, according to the luminance component and according to the chrominance components,
  • Perceptual sub-bands decomposition of said components according to the visibility threshold of a human eye,
  • Extraction of the salient elements of the sub-bands related to the luminance component,
  • Contour enhancement of said salient elements in each sub-band related to the luminance component,
  • Calculation of a saliency map from the contour enhancement, for each sub-band related to the luminance component.
  • Creation of the saliency map as a function of the saliency maps obtained for each sub-band.

Claims

1. In a computer device, a method for creating a saliency map of an image wherein it comprises the steps of:

Projection of said image according to the luminance component and if said image is a color image, according to the luminance component and according to the chrominance components,

Perceptual sub-bands decomposition, by the computer device, of said components according to the visibility threshold of a human eye,

Extraction of the salient elements of the sub-bands related to the luminance component,

Contour enhancement of said salient elements in each sub-band related to the luminance component,

Calculation, by the computer device, of a saliency map from the contour enhancement, for each sub-band related to the luminance component,

Creation of the saliency map as a function of the saliency maps obtained for each sub-band.

2. Method according to claim 1 wherein it comprises, further to the perceptual sub-bands decomposition by the computer device,

a step of achromatic contrast sensitivity function for the luminance component and if said image is a color image,

a step of chromatic sensitivity function for the chromatic components.

3. Method according to claim 2 wherein it comprises a step of visual masking, further to the step of contrast sensitivity function, for each sub-band of the luminance component and of the chromatic components.

4. Method according to claim 3 wherein, when said image is a color image, it comprises a step of chromatic reinforcement of the luminance sub-bands.

5. Method according to claim 1 wherein the perceptual sub-bands decomposition, by the computer, is obtained by carving-up the frequency domain both in spatial radial frequency and orientation.

6. Method according to claim 5 wherein the perceptual decomposition of the luminance component leads to 17 psycho visual sub-bands distributed on four crowns.

7. Method according to claim 5 wherein the perceptual decomposition of the chromatic components leads to 5 psycho visual sub-bands distributed on two crowns for each chromatic component.

8. Method according to claim 4 wherein the chromatic reinforcement of the luminance component is done on the sub-bands of the second crown and based on the sub-bands of the first crown of the chromatic components.

9. A computer readable medium encoded with a computer program, that when executed by a computer devices comprises the steps of:

Projection of said image according to the luminance component and if said image is a color image, according to the luminance component and according to the chrominance components,

Perceptual sub-bands decomposition, by the computer device of said components according to the visibility threshold of a human eye,

Extraction of the salient elements of the sub-bands related to the luminance component,

Contour enhancement of said salient elements in each sub-band related to the luminance component,

Calculation, by the computer device, of a saliency map from the contour enhancement, for each sub-band related to the luminance component,

Creation of the saliency map as a function of the saliency maps obtained for each sub-band.