Two stage detection for photographic eye artifacts
View Patent ↗The detection of red-eye defects is enhanced in digital images for embedded image acquisition and processing systems. A two-stage redeye filtering system includes a speed optimized filter that performs initial segmentation of candidate redeye regions and optionally applies a speed-optimized set of falsing/verification filters to determine a first set of confirmed redeye regions for correction. Some of the candidate regions which are rejected during the first stage are recorded and re-analyzed during a second stage by an alternative set of analysis-optimized filters to determine a second set of confirmed redeye regions.
1. A method of processing a digital image comprising: using a processor;
obtaining candidate face regions of an acquired digital image;
filtering the candidate face regions with a first speed optimized filter to produce a first set of candidate red-eye regions;
encoding at least a portion of the acquired digital image; and
storing the encoded portion of the acquired digital image in association with said first set of candidate red-eye regions for later image processing of said encoded image,
wherein the first speed optimized filter is applied upon image acquisition, and a second analysis-optimized filter is applied in a background or playback mode or both.
2. The method of claim 1 , further comprising applying a speed-optimized set of one or more falsing/verification filters.
3. The method of claim 1 , further comprising passing the first set of candidate redeye regions through an analysis-optimized filter.
4. The method of claim 1 , further comprising passing candidate face regions rejected by the filtering through the analysis-optimized filter sometime after the filtering, encoding and storing.
5. A system for processing a digital image, comprising:
(a) an image acquisition subsystem;
(b) a face detector for obtaining candidate face regions of an acquired digital image;
(c) a speed optimized filter for filtering the candidate face regions to produce a first set of candidate red-eye regions;
(d) a processor for encoding at least a portion of the acquired digital image;
(e) a storage device for storing therein the encoded portion of the acquired digital image in association with said first set of candidate red-eye regions for later image processing of said encoded image; and
(f) an analysis optimized filter for filtering the candidate red-eye regions in a background or playback mode or both,
(g) wherein the speed optimized filter is applied upon image acquisition.
6. The system of claim 5 , wherein the analysis-optimized filter for filtering at least initially rejected candidate face regions to produce a second set of candidate red-eye regions.
7. The system of claim 5 , wherein the analysis-optimized filter for confirming one or more of the first set of candidate red eye regions sometime after speed-optimized filtering.
8. One or more non-transitory, processor-readable media having code embedded therein for programming one or more processors to perform a method of processing a digital image, wherein the method comprises:
obtaining candidate face regions of an acquired digital image;
filtering the candidate face regions with a first speed optimized filter to produce a first set of candidate red-eye regions;
encoding at least a portion of the acquired digital image; and
storing the encoded portion of the acquired digital image in association with said first set of candidate red-eye regions for later image processing of said encoded image,
wherein the first speed optimized filter is applied upon image acquisition, and a second analysis-optimized filter is applied in a background or playback mode or both.
9. The one or more non-transitory, processor-readable media of claim 8 , the method further comprising applying a speed-optimized set of one or more falsing/verification filters.
10. The one or more non-transitory, processor-readable media of claim 8 , the method further comprising passing the first set of candidate redeye regions through an analysis-optimized filter.
11. The one or more non-transitory, processor-readable media of claim 8 , the method further comprising passing candidate face regions rejected by the filtering through the analysis-optimized filter sometime after the filtering, encoding and storing.