Video processing method and circuit using thereof

• US 8,693,809 B2
• Filed: 09/01/2011
• Issued: 04/08/2014
• Est. Priority Date: 09/07/2010
• Status: Active Grant

• Current Assignee: Realtek Semiconductor Corp.
• Original Assignee: Realtek Semiconductor Corp.
• Inventors: Yu, Chia-Wei, Yang, Chia-Yu
• Primary Examiner(s): PATEL, KANJIBHAI B
• Application Number:
  US13/223,661
• Publication Number:
  US 20120057074A1
• Time in Patent Office: 950 Days
• Field of Search: 382/254, 382263-264, 382/266, 382/284, 382298-300, 382/305, 382/312, 348/441, 348/581, 348/625, 348/222.1, 348/630, 345/660, 345/665
• US Class Current: 382/298
• CPC Class Codes: H04N 5/142 Edging; Contouring
• CPC Class Codes: H04N 7/0117 involving conversion of the spatial resolution of the incoming video signal for graphics images G09G2340/0407
• CPC Class Codes: H04N 7/0135 involving interpolation processes interpolation-based image scaling G06T3/4007; interpolation for video coding H04N19/587, H04N19/59

Abstract

A video processing method enlarging and enhancing sharpness of input video data includes following steps. First, N sets of pixel row data of the input video data are respectively buffered in N linear buffers, N is a natural number. Next, I sets of enlarged pixel row data are generated by interpolation according to the buffered N sets of pixel row data in the N linear buffers and a currently inputted set of pixel row data, I is a natural number greater than N. Then, I sets of smoothed and enlarged pixel row data are generated according to the buffered N sets of pixel row data in the N linear buffers and the (N+1)^th set of pixel row data. Thereafter, I sets of sharpness-enhanced pixel row data are obtained according to the I sets of enlarged pixel row data and the I sets of smoothed and enlarged pixel row data.

Claims

1. A video processing circuit for enlarging and enhancing sharpness of input video data, the video processing circuit comprising:

N linear buffers for respectively buffering N sets of pixel row data of the input video data, wherein N is a natural number;

a video scaling circuit for generating I sets of enlarged pixel row data by means of interpolation according to the buffered N sets of pixel row data in the N linear buffers and a currently inputted (N+1)th set of pixel row data, wherein I is a natural number greater than N;

a video smoothing circuit for generating I sets of smoothed and enlarged pixel row data according to the buffered N sets of pixel row data in the N linear buffers and the (N+1)th set of pixel row data; and

a blending circuit for obtaining I sets of high-frequency pixel row data according to the I sets of enlarged pixel row data and the I sets of smoothed and enlarged pixel row data, and obtaining I sets of sharpness-enhanced pixel row data by means of blending according to the I sets of enlarged pixel row data and the I sets of high-frequency pixel row data.

2. The video processing circuit according to claim 1, wherein the video smoothing circuit comprises:

(N−

1) vertical smoothing units, each of which generates one set of vertically smoothed pixel row data according to X sets of pixel row data in the N sets of pixel row data and the (N+1)th set of pixel row data, wherein X is a natural number greater than 1; and

a vertical interpolation unit for performing a vertical interpolation operation according to the (N−

1) sets of vertically smoothed pixel row data to obtain I sets of vertically enlarged and smoothed pixel row data.

3. The video processing circuit according to claim 2, wherein each of the I sets of vertically enlarged and smoothed pixel row data comprises M sets of pixel data, M is a natural number greater than 1, and the video smoothing circuit further comprises:

M horizontal smoothing units for generating one set of horizontally smoothed pixel data according to Y sets of pixel data in each of the I sets of vertically enlarged and smoothed pixel row data, wherein Y is a natural number greater than 1; and

a horizontal interpolation unit for performing a horizontal interpolation operation to obtain J sets of enlarged and smoothed pixel data in each of the I sets of smoothed and enlarged pixel row data according to M sets of the horizontally smoothed pixel data, wherein J is a natural number greater than 1.

4. The video processing circuit according to claim 1, wherein the video scaling circuit comprises:

a vertical interpolation unit for performing a vertical interpolation operation according to the N sets of pixel row data and the (N+1)th set of pixel row data to obtain I sets of vertically enlarged pixel row data; and

a horizontal interpolation unit for performing a horizontal interpolation operation according to each of the I sets of vertically enlarged pixel row data to obtain J sets of enlarged pixel data in each of the I sets of enlarged pixel row data, wherein J is a natural number greater than 1.

5. The video processing circuit according to claim 1, wherein the blending circuit comprises:

an operating unit for obtaining the I sets of high-frequency pixel row data, respectively indicating high-frequency components of the I sets of enlarged pixel row data by means of subtraction according to the I sets of enlarged pixel row data and the corresponding I sets of smoothed and enlarged pixel row data; and

a blending unit for obtaining the I sets of sharpness-enhanced pixel row data by means of blending according to I sets of sharpness weighting coefficients, the I sets of high-frequency pixel row data and the corresponding I sets of enlarged pixel row data.

6. The video processing circuit according to claim 5, wherein the blending circuit further comprises:

a video classifying unit for judging whether each of the N sets of pixel row data and the (N+1)th set of pixel row data satisfies a video characteristic condition and accordingly generating I sets of lookup table control signals; and

a lookup table unit for determining the I sets of sharpness weighting coefficients according to the I sets of lookup table control signals, respectively, to perform a selective sharpness-enhancement operation on the I sets of enlarged pixel row data.

7. A video processing method for enlarging and enhancing sharpness of input video data, the video processing method comprising the steps of:

respectively buffering N sets of pixel row data of the input video data in N linear buffers, wherein N is a natural number;

generating I sets of enlarged pixel row data by means of interpolation according to the buffered N sets of pixel row data in the N linear buffers and a currently inputted (N+1)th set of pixel row data, wherein I is a natural number greater than N;

generating I sets of smoothed and enlarged pixel row data according to the buffered N sets of pixel row data in the N linear buffers and the (N+1)th set of pixel row data; and

obtaining I rows of sharpness-enhanced pixel data by means of blending according to the I sets of enlarged pixel row data and the I sets of smoothed and enlarged pixel row data.

8. The method according to claim 7, wherein the step of generating the I sets of smoothed and enlarged pixel row data comprises:

generating (N−

1) sets of vertically smoothed pixel row data according to X sets of pixel row data of the N sets of pixel row data and the (N+1)th set of pixel row data, wherein X is a natural number greater than 1; and

performing a vertical interpolation operation according to the (N−

1) sets of vertically smoothed pixel row data to obtain I sets of vertically enlarged and smoothed pixel row data.

9. The method according to claim 8, wherein the step of generating the I sets of smoothed and enlarged pixel row data comprises:

generating M sets of horizontally smoothed pixel data according to Y sets of pixel data in each of the I sets of vertically enlarged and smoothed pixel row data, wherein M and Y are natural numbers greater than 1; and

performing a horizontal interpolation operation according to the M sets of horizontally smoothed pixel data to obtain J sets of enlarged and smoothed pixel data in each of the I sets of smoothed and enlarged pixel row data, wherein J is a natural number greater than 1.

10. The method according to claim 7, wherein the step of generating the I sets of enlarged pixel row data comprises:

performing a vertical interpolation operation according to the N sets of pixel row data and the (N+1)th set of pixel row data to obtain I sets of vertically enlarged pixel row data; and

performing a horizontal interpolation operation according to each of the I sets of vertically enlarged pixel row data to obtain J sets of enlarged pixel data in each of the I sets of enlarged pixel row data, wherein J is a natural number greater than 1.

11. The method according to claim 7, wherein the step of obtaining the I sets of sharpness-enhanced pixel row data by means of blending comprises:

obtaining I sets of high-frequency pixel row data, respectively indicating high-frequency components of the I sets of enlarged pixel row data, by means of subtraction according to the I sets of enlarged pixel row data and the corresponding I sets of smoothed and enlarged pixel row data; and

obtaining the I sets of sharpness-enhanced pixel row data by means of blending according to I sets of sharpness weighting coefficients, the I sets of high-frequency pixel row data and the corresponding I sets of enlarged pixel row data.

12. The method according to claim 11, wherein the step of obtaining the I sets of sharpness-enhanced pixel row data by means of blending further comprises:

judging whether each of the N sets of pixel row data and the (N+1)th set of pixel row data satisfies a video characteristic condition, and accordingly generating I sets of lookup table control signals; and

determining the I sets of sharpness weighting coefficients according to the I sets of lookup table control signals to perform a selective sharpness-enhancement operation on the I sets of enlarged pixel row data.