Fast motion estimation method
View Patent ↗An estimated total camera motion between temporally proximate image frames is computed. A desired component of the estimated total camera motion is determined including distinguishing an undesired component of the estimated total camera motion, and including characterizing vector values of motion between the image frames. A counter is incremented for each pixel group having a summed luminance that is greater than a threshold. A counter may be decremented for pixels that are under a second threshold, or a zero bit may be applied to pixels below a single threshold. The threshold or thresholds is/are determined based on a dynamic luminance range of the sequence. The desired camera motion is computed including representing the vector values based on final values of counts for the image frames. A corrected image sequence is generated including the desired component of the estimated total camera motion, and excluding the undesired component.
1. A digital image stabilization method, comprising:
acquiring a sequence of temporally proximate image frames;
computing an estimated total camera motion between the image frames;
determining a desired component of the estimated total camera motion including distinguishing an undesired component of the estimated total camera motion, and including characterizing vector values of motion between the image frames, including:
determining at least first and second thresholds adapted to said image frames to generate a sign value range {−1, 0, +1}, including calculating said thresholds as percentages of a dynamic luminance range of the sequence;
incrementing (+1) a counter for each pixel group having a summed luminance that is greater than a first threshold;
decrementing (−1) said counter for each pixel group having a summed luminance that is less than a second threshold, wherein the counter is unchanged (0), neither incremented nor decremented, for each pixel group having a summed luminance between the first and second thresholds;
determining final values of counts for the image frames by summing along rows and columns; and
representing the vector values of the desired camera motion based on said final values of counts for the image frames;
(d) generating a corrected image sequence including the desired component of the estimated total camera motion, and excluding the undesired component; and
(e) rendering, storing, displaying, transmitting or transferring the corrected image sequence or a further processed version, or combinations thereof.
2. The method of claim 1 , wherein one or more of the groups of pixels each comprise one or more rows or columns of pixels.
3. The method of claim 1 , wherein one or more of the groups of pixels each comprise a single row or a single column of pixels.
4. The method of claim 1 , wherein the undesired component of the estimated total camera motion comprises a jitter component.
5. The method of claim 4 , further comprising compensating for said jitter component through an image shift/warp function.
6. The method of claim 1 , wherein the desired component of the estimated total camera motion comprises a panning component.
7. The method of claim 6 , wherein the undesired component of the estimated total camera motion comprises a jitter component.
8. The method of claim 1 , comprising generating an integer sign value 1 for a vector element that is above the first threshold.
9. The method of claim 8 , comprising generating an integer sign value −1 for a vector element that is below the second threshold.
10. A digital image acquisition device, comprising optics and a processor for respectively capturing and processing an image, and digital code embedded in one or more storage media including instructions for the processors to perform a digital image stabilization method, wherein the method comprises:
acquiring a sequence of temporally proximate image frames;
computing an estimated total camera motion between the image frames;
determining a desired component of the estimated total camera motion including distinguishing an undesired component of the estimated total camera motion, and including characterizing vector values of motion between the image frames, including:
determining at least first and second thresholds adapted to said image frames to generate a sign value range {−1, 0, +1}, including calculating said thresholds as percentages of a dynamic luminance range of the sequence;
incrementing (+1) a counter for each pixel group having a summed luminance that is greater than a first threshold;
decrementing (−1) said counter for each pixel group having a summed luminance that is less than a second threshold, wherein the counter is unchanged (0), neither incremented nor decremented, for each pixel group having a summed luminance between the first and second thresholds;
determining final values of counts for the image frames by summing along rows and columns; and
representing the vector values of the desired camera motion based on said final values of counts for the image frames;
(d) generating a corrected image sequence including the desired component of the estimated total camera motion, and excluding the undesired component; and
(e) rendering, storing, displaying, transmitting or transferring the corrected image sequence or a further processed version, or combinations thereof.
11. The device of claim 10 , wherein one or more of the groups of pixels each comprise one or more rows or columns of pixels.
12. The device of claim 10 , wherein one or more of the groups of pixels each comprise a single row or a single column of pixels.
13. The device of claim 10 , wherein the undesired component of the estimated total camera motion comprises a jitter component.
14. The device of claim 13 , wherein the method further comprises compensating for said jitter component through an image shift/warp function.
15. The device of claim 10 , wherein the desired component of the estimated total camera motion comprises a panning component.
16. The device of claim 15 , wherein the undesired component of the estimated total camera motion comprises a jitter component.
17. The device of claim 10 , wherein the method further comprises generating an integer sign value 1 for a vector element that is above the first threshold.
18. The device of claim 17 , wherein the method further comprises generating an integer sign value −1 for a vector element that is below the second threshold.
19. One or more non-transitory processor-readable storage media having embedded therein code for programming one or more processors to perform a digital image stabilization method, wherein the method comprises:
acquiring a sequence of temporally proximate image frames;
computing an estimated total camera motion between the image frames;
determining a desired component of the estimated total camera motion including distinguishing an undesired component of the estimated total camera motion, and including characterizing vector values of motion between the image frames, including:
determining at least first and second thresholds adapted to said image frames to generate a sign value range {−1, 0, +1}, including calculating said thresholds as percentages of a dynamic luminance range of the sequence;
incrementing (+1) a counter for each pixel group having a summed luminance that is greater than a first threshold;
decrementing (−1) said counter for each pixel group having a summed luminance that is less than a second threshold, wherein the counter is unchanged (0), neither incremented nor decremented, for each pixel group having a summed luminance between the first and second thresholds;
determining final values of counts for the image frames by summing along rows and columns; and
representing the vector values of the desired camera motion based on said final values of counts for the image frames;
generating a corrected image sequence including the desired component of the estimated total camera motion, and excluding the undesired component; and
rendering, storing, displaying, transmitting or transferring the corrected image sequence or a further processed version, or combinations thereof.
20. The one or more non-transitory processor-readable storage media of claim 19 , wherein one or more of the groups of pixels each comprise one or more rows or columns of pixels.
21. The one or more non-transitory processor-readable storage media of claim 19 , wherein one or more of the groups of pixels each comprise a single row or a single column of pixels.
22. The one or more non-transitory processor-readable storage media of claim 19 , wherein the undesired component of the estimated total camera motion comprises a jitter component.
23. The one or more non-transitory processor-readable storage media of claim 22 , wherein the method further comprises compensating for said jitter component through an image shift/warp function.
24. The one or more non-transitory processor-readable storage media of claim 19 , wherein the desired component of the estimated total camera motion comprises a panning component.
25. The one or more non-transitory processor-readable storage media of claim 24 , wherein the undesired component of the estimated total camera motion comprises a jitter component.
26. The one or more non-transitory processor-readable storage media of claim 19 , wherein the method further comprises generating an integer sign value +1 for a vector element that is above the first threshold.
27. The one or more non-transitory processor-readable storage media of claim 26 , wherein the method further comprises generating an integer sign value −1 for a vector element that is below the second threshold.