Two Stage Detection for Photographic Eye Artifacts

• US 20080240555A1
• Filed: 08/02/2006
• Published: 10/02/2008
• Est. Priority Date: 11/18/2005
• Status: Active Grant

• Current Assignee: FotoNation Limited (Adeia Inc.)
• Original Assignee: DigitalOptics Corporation Europe Limited (Adeia Inc.)
• Inventors: Steinberg, Eran, Ciuc, Mihai, Capata, Adrian, Nanu, Florin, Bigioi, Petronel, Corcoran, Peter, Pososin, Alexei
• Granted Patent: US 7,920,723 B2
• Time in Patent Office: Days
• US Class Current: 382/167
• CPC Class Codes: G06T 2207/30216 Redeye defect
• CPC Class Codes: G06T 7/90 Determination of colour characteristics
• CPC Class Codes: G06V 10/50 by performing operations within image blocks; by using histograms, e.g. histogram of oriented gradients [HoG]; by summing image-intensity values; Projection analysis
• CPC Class Codes: G06V 40/193 Preprocessing; Feature extraction

Abstract

A digital image acquisition device is for acquiring digital images including one or more preview images. A face detector analyzes the one or more preview images to ascertain information relating to candidate face regions therein. A speed-optimized filter produces a first set of candidate red-eye regions based on the candidate face region information provided by the face detector.

Claims

1. A digital image acquisition device, comprising:

(a) an imaging optic and detector for acquiring digital images including one or more preview images and a main image;

(b) a processor;

(c) a face detector module for programming a processor to analyze the one or more preview images to ascertain information relating to candidate face regions therein;

(d) an image generating module for programming the processor to generate a sub-sampled version of the main image; and

(e) a first speed-optimized red-eye filter for programming the processor to produce a first set of candidate red-eye regions in a sub-sampled version of the main image based on the candidate face region information provided by the face detector.

2. The device of claim 1, further comprising an image encoder for encoding said acquired image.

3. The device of claim 1, further comprising an image store memory for storing therein said encoded image in association with said first set of candidate red-eye regions for later image processing of said encoded image.

4. The device of claim 1, further comprising an analysis-optimized red eye filter and an image store memory, wherein the image store memory is for storing therein the main image in association with said first set of candidate red-eye regions for later image processing of a full resolution version of the main image by said analysis-optimized red-eye filter.

5. The device of claim 1, further comprising a display for displaying an image processed by said first speed-optimized red-eye filter.

6. The device of claim 1, further comprising an image compressor for compressing said acquired image.

7. The device of claim 1, further comprising a signal connection for transferring said image to a PC or other microprocessor-based device, or both, for further image processing of said encoded image.

8. The device of claim 1, wherein the face detector comprises a search module for detecting candidate face regions and a tracking module for predicting and confirming candidate face regions.

9. The device of claim 1, wherein the one or more preview images comprises a sub-sampled version of an acquired image.

10. The device of claim 1, wherein the candidate face region information comprises:

(i) a list of one or more candidate face regions;

(ii) a set of data associated with one or more candidate face regions and statistical data derived from a history of the one or more candidate face regions;

or

(iii) a predicted location for one or more candidate face regions;

or

(iv) combinations thereof.

11. A processor-based method for filtering a red eye artefact from an acquired digital image based on program instructions embedded within digital memory, the method comprising:

(a) acquiring one or more preview images;

(b) analyzing the one or more preview images to ascertain information relating to candidate face regions therein;

(c) acquiring a main image;

(d) analyzing a sub-sampled version of the main image; and

(e) producing a first set of candidate red-eye regions in the main image based on the candidate face region information in the one or more preview images provided by the face detector and on the analysis of the sub-sampled version of the main image.

12. The method of claim 11, further comprising encoding said main image.

13. The method of claim 12, further comprising storing said encoded main image in association with said first set of candidate red-eye regions for later image processing of said encoded main image.

14. The method of claim 13, further comprising image processing a full resolution version of the main image with an analysis-optimized red eye filter based only in part on information obtained in the previous analyzing.

15. The method of claim 14, further comprising correcting detected red eye artefacts within the main image, and storing a corrected main image.

16. The method of claim 11, further comprising displaying an image processed according to the analyzing of the sub-sampled version of the main image.

17. The method of claim 11, further comprising transferring the main image to a PC or other microprocessor-based device, or both, for further image processing along with information obtained in the previous analyzing.

18. The method of claim 11, further comprising detecting candidate face regions and predicting and confirming candidate face regions.

19. The method of claim 11, wherein the one or more preview images comprises a sub-sampled version of an acquired image.

20. The method of claim 11, wherein the candidate face region information comprises:

(i) a list of one or more candidate face regions;

(ii) a set of data associated with one or more candidate face regions and statistical data derived from a history of the one or more candidate face regions;

or

(iii) a predicted location for one or more candidate face regions;

or

(iv) combinations thereof.

21. One or more storage devices having program instruction embedded therein for programming a processor to perform the method of any of claims 11-20.