Processing 3D image sequences
View Patent ↗Various implementations provide techniques to prevent excessive parallax, depth, or disparity from being passed through to a viewer. In one particular implementation, it is determined that a depth indicator for an object in a stereoscopic image pair of a video sequence is outside of a target range. One or more images of the stereoscopic image pair is modified so that the depth indicator for the object is within the target range. In other implementations, a depth transition between the object and another portion of the video sequence is smoothed. In further implementations, the stereoscopic image pair is replaced with a 2D image pair that includes the object. In yet further implementations, a resulting video sequence includes (i) one or more stereoscopic image pairs having non-zero disparity and for which the depth indicator is within the target range for the entire image pair, and (ii) one or more 2D image pairs.
1. A method comprising:
determining that a depth indicator for an object in a stereoscopic image pair of a video sequence is outside of a target range;
modifying one or more images of the stereoscopic image pair so that the depth indicator for the object is within the target range; and
smoothing a depth transition between the object and another portion of the video sequence, wherein the smoothing is performed until a gradient of the depth indicator is within a target gradient range.
2. The method of claim 1 wherein modifying one or more images of the stereoscopic image pair comprises modifying so that the depth indicator for the object is between zero and a value of the depth indicator for a corresponding object in a previous stereoscopic image pair.
3. The method of claim 1 wherein modifying one or more images of the stereoscopic image pair comprises replacing the stereoscopic image pair with a 2D image pair that includes the object.
4. The method of claim 3 wherein replacing the stereoscopic image pair with the 2D image pair results in a video sequence that includes (i) one or more stereoscopic image pairs having non-zero disparity and for which the depth indicator is within the target range for the entire image pair, and (ii) one or more 2D image pairs.
5. The method of claim 3 further comprising:
determining that the depth indicator is outside of the target range by more than a threshold; and
determining, based on the determination that the threshold is exceeded, to replace the stereoscopic image pair with the 2D image pair.
6. The method of claim 1 wherein smoothing comprises smoothing a depth transition between the object and a region in the stereoscopic image pair.
7. The method of claim 6 wherein the region is adjacent the object.
8. The method of claim 1 wherein smoothing comprises smoothing a depth transition between the object and a corresponding object in a separate image pair of the video sequence.
9. The method of claim 8 wherein the separate image pair occurs prior to the stereoscopic image pair in the video sequence.
10. The method of claim 8 wherein the separate image pair occurs after the stereoscopic image pair in the video sequence.
11. The method of claim 8 wherein the smoothing is performed in the stereoscopic image pair.
12. The method of claim 8 wherein the smoothing is performed in the separate image pair.
13. The method of claim 8 wherein the separate image pair comprises a stereoscopic image pair.
14. The method of claim 8 wherein the separate image pair comprises a 2D image pair.
15. The method of claim 1 wherein smoothing comprises determining a smoothing zone in which the smoothing is performed.
16. The method of claim 15 wherein the smoothing zone comprises a spatial smoothing zone within the stereoscopic image pair and includes a specified width of pixels around the object.
17. The method of claim 16 wherein the spatial smoothing zone is determined with respect to one of the images of the stereoscopic image pair.
18. The method of claim 15 wherein the smoothing zone comprises a temporal smoothing zone and includes one or more stereoscopic image pairs in the video sequence for which the depth indicator of the object is smoothed with respect to a corresponding object in the one or more stereoscopic image pairs.
19. The method of claim 15 wherein smoothing comprises varying the depth indicator linearly throughout the smoothing zone.
20. The method of claim 1 wherein determining that the depth indicator for the object is outside of the target range comprises determining that the depth indicator has exceeded a threshold for at least a predetermined amount of time.
21. An apparatus comprising one or more processors collectively configured for performing:
determining that a depth indicator for an object in a stereoscopic image pair of a video sequence is outside of a target range;
modifying one or more images of the stereoscopic image pair so that the depth indicator for the object is within the target range; and
smoothing a depth transition between the object and another portion of the video sequence, wherein the smoothing is performed until a gradient of the depth indicator is within a target gradient range.
22. An apparatus comprising:
means for determining that a depth indicator for an object in a stereoscopic image pair of a video sequence is outside of a target range;
means for modifying one or more images of the stereoscopic image pair so that the depth indicator for the object is within the target range; and
smoothing a depth transition between the object and another portion of the video sequence, wherein the smoothing is performed until a gradient of the depth indicator is within a target gradient range.