Image processing method and associated image processing circuit

1. An image processing method, comprising:

receiving an image signal, wherein the image signal comprises a first frame and a second frame;

determining edges of a foreground in the first frame and the second frame according to at least one motion vector of the first frame and the second frame;

determining an edge of the foreground in an interpolated frame according to the edge of the foreground in the first frame and the edge of the foreground in the second frame; and

directly using one or more motion vectors of a background adjacent to the foreground in the first frame or the second frame to serve as one or more motion vectors of an outer region of the edge of the foreground in the interpolated frame; wherein the one or more motion vectors of the background in the first frame or the second frame is/are movement amount of block(s) relative to a reference frame, and the one or more motion vectors of the outer region of the edge of the foreground in the interpolated frame is/are also the movement amount of the block(s) relative to the reference frame;

wherein the second frame immediately follows the first frame, and the step of directly using the one or more motion vectors of the background adjacent to the foreground in the first frame or the second frame to serve as the one or more motion vectors of the outer region of the edge of the foreground in the interpolated frame comprises:

when the outer region of the edge of the foreground and the background adjacent to the foreground in the first frame correspond to a same location, directly using the one or more motion vectors of the background adjacent to the foreground in the first frame to serve as the one or more motion vectors of the outer region of the edge of the foreground in the interpolated frame.

2. The image processing method of claim 1 , wherein said at least one motion vector comprises a motion vector of a block of the first frame to a block of the second frame, an edge of the block of the first frame serves as the edge of the foreground in the first frame, and an edge of the block of the second frame serves as the edge of the foreground in the second frame.

3. The image processing method of claim 1 , further comprising:

generating the interpolated frame according to the first frame and the second frame; and

the step of directly using the one or more motion vectors of the background adjacent to the foreground in the first frame or the second frame to serve as the one or more motion vectors of the outer region of the edge of the foreground in the interpolated frame comprises:

resetting the one or more motion vectors of the outer region of the edge of the foreground in the interpolated frame as the one or more motion vectors of the background adjacent to the foreground in the first frame.

4. An image processing method, comprising:

receiving an image signal, wherein the image signal comprises a first frame and a second frame;

determining edges of a foreground in the first frame and the second frame according to at least one motion vector of the first frame and the second frame;

determining an edge of the foreground in an interpolated frame according to the edge of the foreground in the first frame and the edge of the foreground in the second frame; and

directly using one or more motion vectors of a background adjacent to the foreground in the first frame or the second frame to serve as one or more motion vectors of an outer region of the edge of the foreground in the interpolated frame; wherein the one or more motion vectors of the background in the first frame or the second frame is/are movement amount of block(s) relative to a reference frame, and the one or more motion vectors of the outer region of the edge of the foreground in the interpolated frame is/are also the movement amount of the block(s) relative to the reference frame;

wherein the second frame immediately follows the first frame, and the step of directly using the one or more motion vectors of the background adjacent to the foreground in the first frame or the second frame to serve as the one or more motion vectors of the outer region of the edge of the foreground in the interpolated frame comprises:

when the outer region of the edge of the foreground and the background adjacent to the foreground in the second frame correspond to a same location, directly using the one or more motion vectors of the background adjacent to the foreground in the second frame to serve as the one or more motion vectors of the outer region of the edge of the foreground in the interpolated frame.

5. An image processing circuit, comprising:

a receiving circuit, configured to receive an image signal, wherein the image signal comprises a first frame and a second frame;

a motion estimation and motion compensation (MEMC) circuit, coupled to the receiving circuit, configured to determine edges of a foreground in the first frame and the second frame according to at least one motion vector of the first frame and the second frame, determine an edge of the foreground in an interpolated frame according to the edge of the foreground in the first frame and the edge of the foreground in the second frame, and directly use one or more motion vectors of a background adjacent to the foreground in the first frame or the second frame to serve as one or more motion vectors of an outer region of the edge of the foreground in the interpolated frame; wherein the one or more motion vectors of the background in the first frame or the second frame is/are movement amount of block(s) relative to a reference frame, and the one or more motion vectors of the outer region of the edge of the foreground in the interpolated frame is/are also the movement amount of the block(s) relative to the reference frame;

wherein the second frame immediately follows the first frame, and when the outer region of the edge of the foreground and the background adjacent to the foreground in the first frame correspond to a same location, the MEMC directly uses the one or more motion vectors of the background adjacent to the foreground in the first frame to serve as the one or more motion vectors of the outer region of the edge of the foreground in the interpolated frame.

6. The image processing circuit of claim 5 , wherein said at least one motion vector comprises a motion vector of a block of the first frame to a block of the second frame, an edge of the block of the first frame serves as the edge of the foreground in the first frame, and an edge of the block of the second frame serves as the edge of the foreground in the second frame.

7. The image processing circuit of claim 5 , wherein the MEMC circuit generates the interpolated frame according to the first frame and the second frame, and resets the one or more motion vectors of the outer region of the edge of the foreground in the interpolated frame as the one or more motion vectors of the background adjacent to the foreground in the first frame.