Video filtering for stereo images

• US 7,689,031 B2
• Filed: 12/24/2003
• Issued: 03/30/2010
• Est. Priority Date: 12/30/2002
• Status: Active Grant

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Berretty, Robert-Paul Mario, Ernst, Fabian Edgar
• Primary Examiner(s): Mehta; Bhavesh M
• Assistant Examiner(s): Bloom; Nathan
• Application Number:
  US10/540,672
• Publication Number:
  US 20060078180A1
• Time in Patent Office: 2,288 Days
• Field of Search: 382/154, 345418-424, 345/433, 348/51, 348/53
• US Class Current: 382/154
• CPC Class Codes: H04N 13/261 with monoscopic-to-stereoscopic image conversion

Abstract

An image processing system generates an output image from an input image through a depth-dependent transformation. The images are represented as respective pixel arrays. An input 1110 receives for each input pixel an associated input pixel value and input pixel depth. Each input pixel is associated with a respective reconstruction filter footprint. A video processor create the output pixels by, for each input pixel, transforming 1120 the input pixel to a transformed input pixel as a function of the associated input pixel depth and transforming the associated filter footprint to an transformed filter footprint as a function of the associated input pixel depth. The processor also performs a reconstruction filtering operation 1150 on a plurality of the transformed input pixels using the transformed filter footprints. An output 1160 is used for providing the output image for subsequent rendering.

Claims

1. An image processing system for generating at least one output image associated with an output viewpoint from an input image associated with an input viewpoint through a depth-dependent transformation;

the images being represented as an input pixel array and output pixel array, respectively;

the image processing system including;

an input for receiving the input image, where the input image includes for each input pixel an associated input pixel value and input pixel depth, wherein a pixel being indicated by an x-coordinate and a y-coordinate;

each input pixel being associated with a respective reconstruction filter footprint;

a video processor operative to create output pixels of the output image by;

for each input pixel, transforming the input pixel to a transformed input pixel as a function of the associated input pixel depth and transforming the associated filter footprint to an transformed filter footprint as a function of the associated input pixel depth; and

performing a reconstruction filtering operation on a plurality of the transformed input pixels using the transformed filter footprints; and

an output for providing the output image for subsequent rendering, wherein the video processor is operative to determine which transformed filter footprints are fully not-occluded and the video processor is operative to perform the reconstruction filtering operation based on fully not-occluded transformed filter footprints, wherein the video processor being operative to sequentially process input pixels of a row in a direction opposite from a displacement from the input viewpoint to the output viewpoint along the x-axis;

the processing including;

maintaining an x-coordinate extent that indicates for already processed input pixels with respect to a predetermined start position a furthest x-coordinate already occluded by at least one transformed input pixel, where the furthest x-coordinate is a highest x-coordinate if the processing direction is from left-to-right and a lowest x-coordinate if the processing direction is right-to-left; and

determining that a transformed input pixel is occluded from the output viewpoint if processing of the associate input pixel does not result in increasing the x-coordinate extent.

2. An image processing system as claimed in claim 1, wherein the input is operative to receive a hidden image, where the hidden image includes for each hidden pixel an associated hidden pixel value and hidden pixel depth;

the video processor being operative to determining whether or not an output pixel is de-occluded from the output viewpoint and for a de-occluded output pixel perform the reconstruction filtering on a transformed hidden image pixel.

3. An image processing system as claimed in claim 2, wherein the video processor is operative to determine that an output pixel is de-occluded if the transformed input pixel increases the x-coordinate extent by more than a predetermined threshold.

4. An image processing system as claimed in claim 1, wherein the video processor is operative to perform the reconstruction filtering operation using a box filter or a higher order filter.