De-interlacing device capable of de-interlacing video fields adaptively according to motion ratio and associated method
View Patent ↗A de-interlacing device capable of de-interlacing a video field adaptively and associated method, the device includes a video field detector for detecting a video field and for outputting a motion detection parameter, a motion detector for detecting a motion difference between the video frame and at least one video frame neighboring the video frame, and for determining a motion ratio for the motion difference according to the motion detection parameter, and a de-interlacing unit for de-interlacing the video field according to the motion ratio output from the motion detector.
1. A de-interlacing device capable of de-interlacing a video field adaptively, the de-interlacing device comprising:
a video field detector for detecting the video field to output a motion detection parameter;
a motion detector for detecting a motion difference of the video field and a plurality of adjacent video fields neighboring the video field, and for determining a motion ratio for the motion difference according to a motion ratio function selected on the fly from a plurality of motion ratio functions in response to a value of the motion detection parameter; and
a de-interlacing unit for de-interlacing the video field adaptively according to the motion ratio output from the motion detector.
2. The de-interlacing device of claim 1 wherein the video field detector comprises:
a delayer for delaying a pixel of the video field to generate a delayed pixel;
a subtractor for generating a difference value between a pixel value of said pixel and a pixel value of said delayed pixel;
a comparator for comparing the difference value and a plurality of thresholds to output an edge type; and
a selector for outputting the motion detection parameter according to the edge type.
3. The de-interlacing device of claim 1 wherein the video field detector comprises:
a comparator for comparing a pixel value for each pixel for the video field with a plurality of thresholds to output an edge type; and
a selector for outputting the motion detection parameter according to the edge type.
4. The de-interlacing device of claim 1 wherein the motion detector generates the motion ratio by mapping the motion difference through a motion ratio function defined by the motion detection parameter.
5. The de-interlacing device of claim 1 wherein the motion detection parameter represents a lookup table such that the motion detector maps the motion difference to the motion ratio according to the lookup table.
6. The de-interlacing device of claim 1 wherein the adjacent video fields include three video fields nearest to the video field to be de-interlaced.
7. The de-interlacing device of claim 1 wherein the video field is an odd field.
8. The de-interlacing device of claim 1 wherein the video field is an even field.
9. The de-interlacing device of claim 2 wherein the plurality of thresholds comprises a high threshold and a low threshold.
10. The de-interlacing device of claim 3 wherein the plurality of thresholds comprises a high threshold and a low threshold.
11. The de-interlacing device of claim 4 wherein the motion detection parameter comprises a staffing point, a slope, and a saturation value.
12. The de-interlacing device of claim 5 wherein the lookup table is selected from a group consisting of a high motion lookup table, a medium motion lookup table, and a low motion lookup table.
13. A method of de-interlacing a video field adaptively, the method comprising:
detecting a plurality of pixel values in the video field to output a motion detection parameter;
detecting a motion difference between the video field and a plurality of adjacent video fields neighboring the video field;
determining a motion ratio for the motion difference according to a motion ratio function selected on the fly from a plurality of motion ratio functions in response to a value of the motion detection parameter; and
adaptively de-interlacing the video field according to the motion ratio.
14. The method of claim 13 wherein the step of detecting the pixel values maps the motion difference to the motion ratio utilizing a motion ratio function defined by the motion detection parameter.
15. The method of claim 13 wherein the step of detecting the pixel values maps the motion difference to the motion ratio through a lookup table.
16. The method of claim 13 wherein the adjacent video fields include three video fields nearest to the video field to be de-interlaced.
17. The method of claim 13 wherein the step of detecting the pixel values compares the pixel values with a plurality of thresholds to output an edge type according to the motion detection parameter outputted by the edge type.
18. The method of claim 13 wherein the step of detecting the pixel values comprises the following steps:
delaying a pixel of the video field to generate a delayed pixel;
calculating a difference value between the pixel and the delayed pixel;
comparing the difference value and a plurality of thresholds to output an edge type; and
outputting the motion detection parameter according to the edge type.
19. The method of claim 14 wherein the motion detection parameter comprises a starting point, a slope, and a saturation value.
20. The method of claim 18 wherein the difference value is an absolute difference value which is obtained from the difference of the pixel and the delayed pixel.