CN104715454A - Anti-aliasing graph overlapping algorithm - Google Patents

Abstract

The invention provides an anti-aliasing graph overlapping algorithm. The anti-aliasing graph overlapping algorithm is characterized by including the following steps that a graph anti-aliasing coefficient is obtained; pixels are processed one by one, for the ith pixel in a graph, a formula (1) that Si=Fi*alphai+Mi*(1-alphai) can be obtained based on the anti-aliasing pixel mixing principle, Si is the anti-aliasing graph color (known), Fi is the original graph color (known), Mi is the original background color (known), and alphai is the anti-aliasing mixing coefficient (unknown). The anti-aliasing graph overlapping algorithm resolves the 'fringe effect' generated in the anti-aliasing graph overlapping process, and improves the graph quality and visual effect.

Description

A kind of antialiasing figure superposition algorithm

Technical field

The invention belongs to graph and image processing field, particularly relate to edge antialiasing disposal route during a kind of antialiasing Graphics overlay.

Background technology

Along with the development of graphics technology, the application of digital picture is more and more extensive.Digital picture take pixel as elementary cell, by all target object in pixel composing images.Due to the rectangular element that pixel is very little one by one, time with these rectangular elements composition object, more or less can present zigzag fashion at object edge, and antialiasing just refers to and carries out soften handled to image border, image border is made to seem more level and smooth, closer to the object of reality.Antialiasing improves a kind of conventional method of image quality.

In daily use, the antialiasing figure by generating often can be needed superimposed with other graph images.Antialiasing figure is when generation, and the pixel color of pattern edge can be transformed into the mixed gradient look of graphic color and background color, makes the transition of two kinds of colors look more natural.By antialiasing figure and other imaging importing, if improper to pattern edge processes pixel, these edge pixels will seem very inharmonious (we are referred to as " edge effect ") in newly-generated superimposed image, greatly reduce picture quality, so these edge pixels and new background must be re-started mixing antialiasing.Traditional disposal route mainly deposits shortcoming both ways: one be process effect undesirable; Two is need a large amount of calculating or extra information (as " degree of depth " information).So, in order to better solve " edge effect " problem of antialiasing Graphics overlay, process careful more fast must be carried out to the image of superposition.

Summary of the invention

In order to solve technical matters existing in background technology, the present invention proposes a kind of method of antialiasing Graphics overlay, " edge effect " that produce when solving antialiasing Graphics overlay, improving picture quality and strengthening visual effect.

Technical solution of the present invention is: a kind of antialiasing figure stacking method, is characterized in that: said method comprising the steps of:

1) figure antialiasing coefficient is obtained: pixel is processed one by one, for the pixel of i-th in image, according to the pixel mixing principle of antialiasing, formula (1) can be obtained: S _i=F _iα _i+ M _i(1-α _i) ... ... ... ... ... (1)

S _iantialiasing graphic color (known), F _iformer graphic color (known), M _iformer background color (known), α _iantialiasing mixing constant (the unknown);

2) antialiasing factor alpha is drawn according to formula (1) _icomputing formula:

${\mathrm{\α}}_i=\frac{(S_i-M_i)}{(F_i-M_i)}..............................\left(2\right)$

Each pixel comprises red (R), green (G), blue (B) three color components, antialiasing factor alpha _iequal the antialiasing coefficient value of one-component max (R, G, B) maximum in R, G, B tri-components;

3) the antialiasing factor alpha will calculated _i, be updated in formula (6), (7), (8), calculate the carrying out superposition of antialiasing figure and new background and R, G, B tri-value of colouring component of i-th pixel after antialiasing again; T _{i (R)}=F _{i (R)}α _i+ N _{i (R)}(1-α _i) ... ... ... ... ... (6) T _{i (G)}=F _{i (G)}α _i+ N _{i (G)}(1-α _i) ... ... ... ... ... (7) T _{i (B)}=F _{i (B)}α _i+ N _{i (B)}(1-α _i) ... ... ... ... ... (8)

T _{i (R)}, T _{i (G)}, T _{i (B)}the value (the unknown) of red, green, blue three colouring component of synthetic image after final superposition respectively, N _{i (R)}, N _{i (G)}, N _{i (B)}the value (known) of red, green, blue three colouring component of new background image respectively.

Above-mentioned steps 2) antialiasing factor alpha _iconcrete acquisition pattern be:

2.1) as max (R, G, B)=R, factor alpha _icalculated by formula (3), S _{i (R)}represent the red color component value of antialiasing figure, F _{i (R)}represent the red color component value of former figure, M _{i (R)}represent the red color component value of former background;

${\mathrm{\α}}_i=\frac{(S_{i\left(R\right)}-M_{i\left(R\right)})}{(F_{i\left(R\right)}-M_{i\left(R\right)})}..............................\left(3\right)$

2.2) as max (R, G, B)=G, factor alpha _icalculated by formula (4), S _{i (G)}represent the green component values of antialiasing figure, F _{i (G)}represent the green component values of former figure, M _{i (G)}represent the green component values of former background;

${\mathrm{\α}}_i=\frac{(S_{i\left(G\right)}-M_{i\left(G\right)})}{(F_{i\left(G\right)}-M_{i\left(G\right)})}...........................\left(4\right)$

2.3) as max (R, G, B)=B, factor alpha _icalculated by formula (5), S _{i (B)}represent the blue color component value of antialiasing figure, F _{i (B)}represent the blue color component value of former figure, M _{i (B)}represent the blue color component value of former background.

${\mathrm{\α}}_i=\frac{(S_{i\left(B\right)}-M_{i\left(B\right)})}{(F_{i\left(B\right)}-M_{i\left(B\right)})}...........................\left(5\right)$

The present invention fundamentally solves " edge effect " that antialiasing Graphics overlay brings, and improves picture quality, enhances visual effect.Be applied to certain type helicopter display and control board, the figure drawn for video card in integrated display system and the superposition of other video datas, result of use is good.

Accompanying drawing explanation

Fig. 1 is method flow diagram of the present invention;

Embodiment

See Fig. 1, " edge effect " that produce when the present invention is directed to antialiasing Graphics overlay, proposes a kind of antialiasing figure stacking method.Due to the hybrid processing that antialiasing process and overlap-add procedure are all to pixel color in itself, therefore, antialiasing principle is applied in overlap-add procedure by the core concept of this method exactly, the mixing superposition of figure and former background is regarded in antialiasing process as, antialiasing mixing constant is applied to the mixing overlap-add procedure of figure and new background.For each pixel in figure, calculating at the blend of colors coefficient of former figure when carrying out antialiasing process, then when overlap-add procedure, utilizing this coefficient to re-start antialiasing, being divided into following two steps to carry out:

1) figure antialiasing coefficient is derived: process one by one pixel, for the pixel of i-th in image, according to the pixel mixing principle of antialiasing, can obtain formula (1): S _i=F _iα _i+ M _i(1-α _i) ... ... ... ... ... (1)

S _iantialiasing graphic color (known), F _iformer graphic color (known), M _iformer background color (known), α _iantialiasing mixing constant (the unknown).

According to formula (1), antialiasing factor alpha can be derived _icomputing formula:

${\mathrm{\α}}_i=\frac{(S_i-M_i)}{(F_i-M_i)}..............................\left(2\right)$

Each pixel comprises red (R), green (G), blue (B) three color components, and cause the dominant hue of pixel color to change in order to avoid three look increase and decrease ratio disunities, therefore, this algorithm all processes three looks according to same ratio.Antialiasing factor alpha _iequal the antialiasing coefficient value of one-component max (R, G, B) maximum in R, G, B tri-components.

As max (R, G, B)=R, factor alpha _icalculated by formula (3), S _{i (R)}represent the red color component value of antialiasing figure, F _{i (R)}represent the red color component value of former figure, M _{i (R)}represent the red color component value of former background.

${\mathrm{\α}}_i=\frac{(S_{i\left(R\right)}-M_{i\left(R\right)})}{(F_{i\left(R\right)}-M_{i\left(R\right)})}..............................\left(3\right)$

As max (R, G, B)=G, factor alpha _icalculated by formula (4), S _{i (G)}represent the green component values of antialiasing figure, F _{i (G)}represent the green component values of former figure, M _{i (G)}represent the green component values of former background.

${\mathrm{\α}}_i=\frac{(S_{i\left(G\right)}-M_{i\left(G\right)})}{(F_{i\left(G\right)}-M_{i\left(G\right)})}..............................\left(4\right)$

As max (R, G, B)=B, factor alpha _icalculated by formula (5), S _{i (B)}represent the blue color component value of antialiasing figure, F _{i (B)}represent the blue color component value of former figure, M _{i (B)}represent the blue color component value of former background.

${\mathrm{\α}}_i=\frac{(S_{i\left(B\right)}-M_{i\left(B\right)})}{(F_{i\left(B\right)}-M_{i\left(B\right)})}..............................\left(5\right)$

2) antialiasing is again superposed also with new background

The antialiasing factor alpha that previous step is calculated _i, be updated in formula (6), (7), (8), the carrying out superposition of antialiasing figure and new background can be calculated and R, G, B tri-value of colouring component of i-th pixel after antialiasing again.T _i(R)＝F _i(R)·α _i+N _i(R)·(1-α _i)..............................(6)T _i(G)＝F _i(G)·α _i+N _i(G)·(1-α _i)..............................(7)T _i(B)＝F _i(B)·α _i+N _i(B)·(1-α _i)..............................(8)

T _{i (R)}, T _{i (G)}, T _{i (B)}the value (the unknown) of red, green, blue three colouring component of synthetic image after final superposition respectively, N _{i (R)}, N _{i (G)}, N _{i (B)}the value (known) of red, green, blue three colouring component of new background image respectively.

Claims (2)

1. an antialiasing figure stacking method, is characterized in that: said method comprising the steps of:

1) figure antialiasing coefficient is obtained: pixel is processed one by one, for the pixel of i-th in image, according to the pixel mixing principle of antialiasing, formula (1) can be obtained: S _i=F _iα _i+ M _i(1-α _i) ... ... ... ... ... (1)

S _iantialiasing graphic color (known), F _iformer graphic color (known), M _iformer background color (known), α _iantialiasing mixing constant (the unknown);

2) antialiasing factor alpha is drawn according to formula (1) _icomputing formula:

${\mathrm{\α}}_i=\frac{(S_i-M_i)}{(F_i-M_i)}..............................\left(2\right)$

Each pixel comprises red (R), green (G), blue (B) three color components, antialiasing factor alpha _iequal the antialiasing coefficient value of one-component max (R, G, B) maximum in R, G, B tri-components;

3) the antialiasing factor alpha will calculated _i, be updated in formula (6), (7), (8), calculate the carrying out superposition of antialiasing figure and new background and R, G, B tri-value of colouring component of i-th pixel after antialiasing again; T _i(R)=F _{i (R)}α _i+ N _{i (R)}(1-α _i) ... ... ... ... ... (6) T _{i (G)}=F _{i (G)}α _i+ N _{i (G)}(1-α _i) ... ... ... ... ... (7) T _{i (B)}=F _{i (B)}α _i+ N _{i (B)}(1-α _i) ... ... ... ... ... (8)

T _{i (R)}, T _{i (G)}, T _{i (B)}the value (the unknown) of red, green, blue three colouring component of synthetic image after final superposition respectively, N _{i (R)}, N _{i (G)}, N _{i (B)}the value (known) of red, green, blue three colouring component of new background image respectively.

2. antialiasing figure stacking method according to claim 1, is characterized in that: described step 2) antialiasing factor alpha _iconcrete acquisition pattern be:

2.1) as max (R, G, B)=R, factor alpha _icalculated by formula (3), S _{i (R)}represent the red color component value of antialiasing figure, F _{i (R)}represent the red color component value of former figure, M _{i (R)}represent the red color component value of former background;

${\mathrm{\α}}_i=\frac{(S_{i\left(R\right)}-M_{i\left(R\right)})}{(F_{i\left(R\right)}-M_{i\left(R\right)})}..............................\left(3\right)$

2.2) as max (R, G, B)=G, factor alpha _icalculated by formula (4), S _{i (G)}represent the green component values of antialiasing figure, F _{i (G)}represent the green component values of former figure, M _{i (G)}represent the green component values of former background;

${\mathrm{\α}}_i=\frac{(S_{i\left(G\right)}-M_{i\left(G\right)})}{(F_{i\left(G\right)}-M_{i\left(G\right)})}..............................\left(4\right)$

2.3) as max (R, G, B)=B, factor alpha _icalculated by formula (5), S _{i (B)}represent the blue color component value of antialiasing figure, F _{i (B)}represent the blue color component value of former figure, M _{i (B)}represent the blue color component value of former background

${\mathrm{\α}}_i=\frac{(S_{i\left(B\right)}-M_{i\left(B\right)})}{(F_{i\left(B\right)}-M_{i\left(B\right)})}..............................\left(5\right).$