CN1141841C - 75H2 linear line interpolation and field frequency boosting method for digital TV - Google Patents

Abstract

The present invention discloses a digital TV 75Hz linear line interpolation and field frequency raising method which comprises linear line interpolation and field frequency raising, wherein the linear line interpolation is that 625 scanning lines of a source signal are changed into 833 scanning lines, and the vertical definition of an image is increased. The field frequency raising is that 50Hz field frequency is changed into 75Hz field frequency, and the linear line interpolation uses sampling in the ratio of four to three. An interleaved signals is combined into a sequential signal, and then three new interpolation lines are generated between two lines through linear interpolation. Through the sampling in the ratio of four to three, the sequential signal of which vertical resolution is 833 lines is obtained, and the obtained sequential signal is divided into an odd field and an even field. The field frequency raising uses three kinds of schemes, and through motion compensation algorithm, a filtered sequential video signal can protect the edge characteristic of the image very well. The difference of signals in odd and even fields, which is caused by the movement of the image can be corrected, and consequently the edge faintness of the image is reduced. In the design of the present invention, the complexity of hardware realization is fully considered, and realization cost is lowered.

Description

Interpolation of a kind of Digital Television 75Hz linear rows and field frequency method for improving

One, affiliated field

The invention belongs to and calculate video, television scanning format conversion technical field, specially refer to interpolation of 75Hz linear rows and field frequency method for improving in the Digital Television.

Two, background technology

The scan format conversion is the common issue with that calculating video, high definition TV and the traditional tv under the current network environment exists, and scan format need be changed between different standards, is the very important research field of present digital to television.The scan format that existing HDTV receiver is commonly used has 50Hz line by line, 60Hz line by line, the 100Hz interlacing.50Hz can solve preferably line by line with 60Hz line by line and in the ranks creep and row structure phenomenon, but still has significantly large-area flicker phenomenon.The 100Hz interlace mode has well solved the large-area flicker phenomenon, but row structure and creeping phenomenon are obvious.Under the situation of given bandwidth, line frequency and field frequency are that spatial resolution and this contradiction of temporal resolution are the key factors that influences HDTV picture quality.But also there is not a kind of scheme can well solve image large-area flicker and interline flicker problem simultaneously at present.

Three, summary of the invention

Defective or deficiency at above-mentioned prior art existence, in order to remedy the defective of above algorithm, the object of the present invention is to provide a kind of cost low, be convenient to interpolation of hard-wired Digital Television 75Hz linear rows and field frequency method for improving, can well solve image large-area flicker and interline flicker problem simultaneously.

To achieve these goals, the solution that the present invention adopts is: this Digital Television 75Hz linear rows interpolation and field frequency method for improving, comprise that linear rows interpolation and field frequency promote two parts, it is characterized in that: the linear rows interpolation is two interlace signals that the interlace signal of two 312.5 row are transformed to 416.5 row, increase the vertical definition of image, it is that the 50Hz field frequency is become the 75Hz field frequency that field frequency promotes;

1) linear rows interpolating method:

Linear rows interpolation: the progressive signal that at first two direct interpolations of interlace signal of 312.5 row is synthesized a frame 625 row, between per two row of progressive signal, produce 3 interpolation lines that make new advances then through linear interpolation, then through sampling in 1: 3, promptly obtain the progressive signals that vertical resolution is 833 row, sampling in promptly 4: 3 every two capable modes of getting delegation; Two of odd evens that at last progressive signal that obtains are divided into 416.5 row, two of this odd evens are two of outputs after the linear rows interpolation;

2) field frequency promotes and adopts following method to carry out:

Scheme is 1.:

A, b, four implementations of e, f: interpolation obtains 416.5 two interlace signal A ' 1, the B ' 1 that go through linear rows by A1, B1 two field signals, and A ' 1 is output a field signal, and B ' 1 is output b field signal; Interpolation obtains 416.5 two interlace signal A ' 2, the B ' 2 that go through linear rows for A2, B2 two field signals, and A ' 2 is output e field signal, and B ' 2 is output f field signal;

Two of the implementation that c, d are two: c, d are the interpolation field, A1, A2 two field signals carry out the average computing, adopt 3 * 3 windows, 3 direction (α then, β, γ) 6 point self-adapted motion compensated filterings go the interlacing algorithm to form the frame signal of 625 row, generate 833 frame signals of going by sampling in 4: 3, frame signal is split into 416.5 two interlace signals of odd even of going, get strange field and be output c field signal.B1, B2 two field signals carry out the average computing, adopt 3 * 3 windows, 3 direction (α then, β, γ) 6 point self-adapted motion compensated filterings go the interlacing algorithm to form the frame signal of 625 row, generate the frame signal of 833 row by sampling in 4: 3, frame signal is split into 416.5 two interlace signals of odd even of going, gets the idol field and be output d field signal;

1. can derive other two kinds of field frequency lifting schemes from scheme, specifically be expressed as follows:

Scheme is 2.:

A, b, four implementations of e, f: interpolation obtains 416.5 two interlace signal A ' 1, the B ' 1 that go through linear rows by A1, B1 two field signals, and A ' 1 is output a field signal, and B ' 1 is output b field signal; Interpolation obtains 416.5 two interlace signal A ' 2, the B ' 2 that go through linear rows for A2, B2 two field signals, and A ' 2 is output e field signal, and B ' 2 is output f field signal;

Two implementations of c, d: the c field is by B1 field 3 * 3 windows, 3 direction (α, β, γ) 6 point self-adapted motion compensated filterings go the interlacing algorithm to form the frame signal of 625 row, generate the frame signal of 833 row then through sampling in 4: 3, frame signal is split into 416.5 two interlace signals of odd even of going, gets strange field and obtain c field output signal; The d field is by A2 field 3 * 3 windows, 3 direction (α, beta, gamma) 6 point self-adapted motion compensated filterings go the interlacing algorithm to form the frame signal of 625 row, generate 833 frame signals of going through sampling in 4: 3 then, frame signal is split into 416.5 two interlace signals of odd even of going, gets the idol field and obtain d field output signal;

Scheme is 3.:

A field implementation: the interlace signal that obtains 416.5 row through sampling in 4: 3 by the A1 field signal is output a field signal;

Two implementations of b, c: obtain 416.5 interlace signals of going by the B1 field signal through sampling in 4: 3, this interlace signal while is as the output signal of two of b, c;

Two implementations of d, e: obtain 416.5 interlace signals of going by the A2 field signal through sampling in 4: 3, this interlace signal while is as the output signal of two of d, e;

F field implementation: the interlace signal that obtains 416.5 row through sampling in 4: 3 by the B2 field signal is output f field signal.

Some other characteristics of the present invention are:

Described 3 * 3 windows, 3 directions (α, beta, gamma) 6 point self-adapted motion compensated filterings go the interlacing algorithm to be:

1) establish size and represent with I, and size is N * M for the image that N * M/2 interlaced video image process is interlaced to behind the progressive scanning conversion; Arbitrary position P at image _Ij(wherein, i=1 ..., N, j=1 ..., the I (P of pixel M) _Ij) expression, i wherein, j is respectively the coordinate of row and column; When i is odd number, represent current from strange field signal; When i is even number, represent current from even field signal;

2) establish I (P _Ij) be the image border point, this point must be on the direction of its gradient minimum, promptly in the gray-value variation minimum of image edge direction epigraph: get with an I (P _Ij) be 3 * 3 windows at center, definable I (P _Ij) three directions: α direction, β direction and γ direction, and can obtain an I (P _Ij) at α, the gradient on these three directions of beta, gamma is:

3) absolute value of gradient as from the foregoing, | _αF|, | _βF| and | _γThe direction of f| minimum is exactly that current frame image is at an I (P _Ij) edge direction located;

So adaptive motion compensated filtering goes the output of interlacing algorithm to be defined as: $g\left(P_{\mathrm{ij}}\right)=\frac{1}{2}\{f_{\mathrm{up}}+f_{\mathrm{down}}\}---\left(2\right)$

Perhaps

g(P _ij)＝Med{f _up，f _down} (3)

Wherein

f _Up=I (P _{(i+1) (j-1)}), f _Down=I (P _{(i-1) (j+1})) when | _αF| is a minimum value

f _Up=I (P _{(i) (j-1)}), f _Down=I (P _{(i) (j+1)}) when | _βF| is minimum value (4)

f _Up=I (P _{(i-1) (j-1)}), f _Down=I (P _{(i+1) (j+1)}) when | _γF| is a minimum value

By 3 * 3 windows, 3 direction (α; β; γ) 6 point self-adapted motion compensated filterings remove the progressive video signal behind the interlacing algorithm; can protect the edge of image characteristic well; so just can the modifying factor image motion and cause differences strange, idol two field signals, thus the edge of image blooming reduced.

Sampling algorithm was in described 4: 3:

1) size of establishing image is N * M, and I1, I2, I3, I4 are the line displays of received image signal, and O1, O2, O3, O4, O5 are the line displays of the output image signal after sampling in 4: 3, and L1, L2, L3 insert row; On I1, I2, I3, the I4 of input picture is capable, get I respectively _Ij, I _{I (j+1)}, I _{I (j+2)}, I _{I (j+3)}Four points (wherein, i=1 ..., N, j=1 ..., M); Get L respectively on three insertion row _{I (j+3)}, L _{I (j+6)}, L _{I (j+9)}3 points; Get O respectively on five output row _Ij, O _{I (j+l)}, O _{I (j+2)}, O _{I (j+3)}, O _{I (j+4)}5 points;

2) linear insertion four lines between two row of original image, L1, L2, L3 adopt linear interpolation to draw, and therefore have

L _i(j+3)＝(I _ij+3I _i(j+1))/4

L _i(j+6)＝(I _i(j+1)+I _i(j+2))/2 (5)

L _i(j+9)＝(3I _i(j+2)+I _i(j+3))/4

3) extract delegation every two row in the frame that after linearity is inserted row, obtains, obtain the output image of sampling in final 4: 3; Its pass is:

O _ij＝I _ij (6)

O _i(j+1)＝L _i(j+3)＝(I _ij+3I _i(j+1))/4

O _i(j+2)＝L _i(j+6)＝(I _i(j+1)+I _i(j+2))/2

O _i(j+3)＝L _i(j+9)＝(3I _i(j+2)+I _i(j+3))/4

O _i(j+4)＝I _i(j+3)

The present invention has fully taken into account hard-wired complexity in design, reduced the realization cost.

Four, description of drawings

Fig. 1 is linear rows interpolation principle figure of the present invention;

Fig. 2 is 4: 3 sampling algorithm schematic diagrams;

Fig. 3 is four field storage modes among the present invention;

Fig. 4 is the schematic diagram of field frequency lifting scheme one of the present invention; Fig. 4 (a) is a, b, and e, f four field interpolation schemes, Fig. 4 (b) is a c field interpolation scheme, Fig. 4 (c) is a d field interpolation scheme;

Fig. 5 is the present invention program one the input field and the interpolation relation principle figure of output field;

Fig. 6 is the schematic diagram of field frequency lifting scheme two of the present invention; Fig. 6 (a) is a, b, and e, f four field interpolation schemes, Fig. 6 (b) is a c field interpolation scheme, Fig. 6 (c) is a d field interpolation scheme;

Fig. 7 is the present invention program two the input field and the interpolation relation principle figure of output field;

Fig. 8 is the schematic diagram of field frequency lifting scheme three of the present invention;

Fig. 9 is the present invention program three the input field and the interpolation relation principle figure of output field;

Figure 10 is that the present invention's 3 * 3 windows 3 directions (α, beta, gamma) 6 point self-adapted motion compensated filterings remove interlacing algorithm schematic diagram.

Five, embodiment

The present invention is described in further detail below in conjunction with accompanying drawing.

The designer has provided three implementations of the present invention.But the invention is not restricted to this three kinds of schemes, the algorithm in linear rows interpolation and the field frequency lifting is done a change can derive multiple scheme.In implementation process, the capable interpolation of advanced line linearity is done field frequency then and is promoted.

Figure 1 shows that linear rows interpolation principle figure, the progressive signal that at first two direct interpolations of interlace signal of 312.5 row is synthesized a frame 625 row, between per two row of progressive signal, produce 3 interpolation lines that make new advances then through linear interpolation, then through sampling in 1: 3, promptly obtain the progressive signals that vertical resolution is 833 row, sampling in promptly 4: 3 every two capable modes of getting delegation; Two of odd evens that at last progressive signal that obtains are divided into 416.5 row, two of this odd evens are two of outputs after the linear rows interpolation;

Fig. 2 is 4: 3 sampling algorithm schematic diagrams.I1, I2, I3, I4 are the line displays of received image signal, and O1, O2, O3, O4, O5 are the line displays of the output image signal after sampling in 4: 3, and L1, L2, L3 insert row.

Sampling algorithm was in 4: 3:

1) size of establishing image is N * M, and I1, I2, I3, I4 are the line displays of received image signal, and O1, O2, O3, O4, O5 are the line displays of the output image signal after sampling in 4: 3, and L1, L2, L3 insert row; On I1, I2, I3, the I4 of input picture is capable, get I respectively _Ij, I _{I (j+1)}, I _{I (j+2)}, I _{I (j+3)}Four points (wherein, i=1 ..., N, j=1 ..., M); Get L respectively on three insertion row _{I (j+3)}, L _{I (j+6)}, L _{I (j+9)}3 points; Get O respectively on five output row _Ij, O _{I (j+1)}, O _{I (j+2)}, O _{I (j+3)}, O _{I (j+4)}5 points;

2) linear insertion four lines between two row of original image, L1, L2, L3 adopt linear interpolation to draw, and therefore have

L _i(j+3)＝(I _ij+3I _i(j+1))/4

L _i(j+6)＝(I _i(j+1)+I _i(j+2))/2 (5)

L _i(j+9)＝(3I _i(j+2)+I _i(j+3))/4

3) extract delegation every two row in the frame that after linearity is inserted row, obtains, obtain the output image of sampling in final 4: 3; Its pass is:

O _ij＝I _ij

O _i(j+1)＝L _i(j+3)＝(I _ij+3I _i(j+1))/4

O _i(j+2)＝L _i(j+6)＝(I _i(j+1)+I _i(j+2))/2 (6)

O _i(j+3)＝L _i(j+9)＝(3I _i(j+2)+I _i(j+3))/4

O _i(j+4)＝I _i(j+3)

Fig. 3 is one of 75Hz field frequency lifting scheme.A1, B1, A2, B2 are four former interlacing signals of Phase Alternation Line system, and its location mode in SDRAM (synchronous DRAM) is seen Fig. 3.

Fig. 4 (a) is a field frequency lifting scheme block diagram, and interpolation obtains two interlace signal A ' 1, the B ' 1 of 416.5 row through linear rows by A1, B1 two field signals for four of a, b, e, f, and A ' 1 is output a field signal, and B ' 1 is output b field signal; Interpolation obtains 416.5 two interlace signal A ' 2, the B ' 2 that go through linear rows for A2, B2 two field signals, and A ' 2 is output e field signal, and B ' 2 is output f field signal; Fig. 4 (b) is a c field interpolation scheme, A1, A2 two field signals carry out the average computing, adopt 3 * 3 windows, 3 direction (α then, β, γ) 6 point self-adapted motion compensated filterings go the interlacing algorithm to form the frame signal of 625 row, generate 833 frame signals of going by sampling in 4: 3, frame signal is split into 416.5 two interlace signals of odd even of going, get strange field and be output c field signal.Fig. 4 (c) is a d field interpolation scheme, B1, B2 two field signals carry out the average computing, adopt 3 * 3 windows, 3 direction (α then, β, γ) 6 point self-adapted motion compensated filterings go the interlacing algorithm to form the frame signal of 625 row, generate 833 frame signals of going by sampling in 4: 3, frame signal is split into 416.5 two interlace signals of odd even of going, get the idol field and be output d field signal;

Figure 5 shows that the input and the interpolation time chart of output field.As can be seen from the figure, a, b, c, d, each interpolation frame of e, f of interlacing output are relevant with two interlace signal sources of input.Interpolation algorithm changes along with different.

The designer has provided second scheme of the present invention.Scheme two is that with the difference of scheme one realization of c, d two frames is different, and the implementation method of other frame and scheme one are in full accord.

Fig. 6 (b) is depicted as the implementation of c field in the 75Hz field frequency lifting scheme two, as can be seen, the c field is by B1 field 3 * 3 windows, 3 direction (α, β, γ) 6 point self-adapted motion compensated filterings go the interlacing algorithm to form the frame signal of 625 row, generate the frame signal of 833 row then through sampling in 4: 3, frame signal is split into 416.5 two interlace signals of odd even of going, get strange field and obtain c field output signal; Fig. 6 (c) is depicted as the implementation of d field in the 75Hz field frequency lifting scheme two, the d field is by A2 field 3 * 3 windows, 3 direction (α, β, γ) 6 point self-adapted motion compensated filterings go the interlacing algorithm to form the frame signal of 625 row, generate the frame signal of 833 row then through sampling in 4: 3, frame signal is split into 416.5 two interlace signals of odd even of going, gets the idol field and obtain d field output signal;

Fig. 7 is the input field of scheme two and the interpolation relation of output field, and two of c, d are only relevant with a field signal as can be seen, and all the other are then relevant with two field signals.

What deserves to be explained is that especially for the 3rd scheme of the present invention that the designer provides, this scheme and scheme one and scheme two have bigger difference.

Fig. 8 is that the field frequency of scheme three promotes schematic diagram.The A1 field signal obtains 416.5 interlace signals of going through sampling in 4: 3, is output a field signal; The B1 field signal obtains 416.5 interlace signals of going through sampling in 4: 3, is output b, c field signal; The A2 field signal obtains 416.5 interlace signals of going through sampling in 4: 3, is output d, e field signal; The B2 field signal obtains 416.5 interlace signals of going through sampling in 4: 3, is output f field signal.

Fig. 9 is the present invention program three the input field and the interpolation relation principle figure of output field.Every output signal is only relevant with the field signal in the input field as can be seen.

The interpolation of c, d two field signals need relate to the interlacing processing in 75Hz field frequency lifting scheme one and the scheme two.

Adopt 3 * 3 windows, 3 directions (α, beta, gamma), 6 point self-adapted motion compensated filterings to remove the interlacing algorithm among the present invention.Figure 10 is the schematic diagram of this algorithm.Can protect the edge of image characteristic well by the filtered progressive video signal of movement compensating algorithm.

3 * 3 windows, 3 directions (α, beta, gamma), 6 point self-adapted motion compensated filterings go the interlacing algorithm to be:

1) establish size and represent with I, and size is N * M for the image that N * M/2 interlaced video image process is interlaced to behind the progressive scanning conversion; Arbitrary position P at image _Ij, (wherein, i=1 ..., N, j=1 ..., the I (P of pixel M) _Ij) expression, i wherein, j is respectively the coordinate of row and column; When i is odd number, represent current from strange field signal; When i is even number, represent current from even field signal;

2) establish I (P _Ij) be the image border point, this point must be on the direction of its gradient minimum, promptly in the gray-value variation minimum of image edge direction epigraph; Get with an I (P _Ij) be 3 * 3 windows at center, definable I (P _Ij) three directions: α direction, β direction and γ direction, and can obtain an I (P _Ij) at α, the gradient on these three directions of beta, gamma is:

3) absolute value of gradient as from the foregoing, | _αF|, | _βF| and | _γThe direction of f| minimum is exactly that current frame image is at an I (P _Ij) edge direction located;

So adaptive motion compensated filtering goes the output of interlacing algorithm to be defined as: $g\left(P_{\mathrm{ij}}\right)=\frac{1}{2}\{f_{\mathrm{up}}+f_{\mathrm{down}}\}---\left(2\right)$

Perhaps

g(P _ij)=Med{f _up，f _down} (3)

Wherein

f _Up=I (P _{(i+1) (j-1)}), f _Down=I (P _{(i-1) (j+1)}) when | _αF| is a minimum value

f _Up=I (P _{(i) (j-1)}), f _Down=I (P _{(i) (j+1)}) when | _βF| is minimum value (4)

f _Up=I (P _{(i-1) (j-1)}), f _Down=I (P _{(i+1) (j+1)}) when | _γF| is a minimum value

Formula (2) and (3) are based on such principle: if current some I (P _Ij) gray value and detect the grey value difference of neighborhood inward flange direction when big, the image neighborhood that the current pixel position just is described has motion, then directly get the gray value that detects on the neighborhood inward flange, so just can the modifying factor image motion and cause differences strange, idol two field signals, thus the edge of image blooming reduced.

For the different interlacing algorithms that go, the present invention can corresponding multiple implementation.

Claims (5)

1. Digital Television 75Hz linear rows interpolation and field frequency method for improving, comprise that linear rows interpolation and field frequency promote two parts, it is characterized in that: the linear rows interpolation is two interlace signals that the interlace signal of two 312.5 row are transformed to 416.5 row, increase the vertical definition of image, it is that the 50Hz field frequency is become the 75Hz field frequency that field frequency promotes;

1) linear rows interpolating method:

Linear rows interpolation: the progressive signal that at first two direct interpolations of interlace signal of 312.5 row is synthesized a frame 625 row, between per two row of progressive signal, produce 3 interpolation lines that make new advances then through linear interpolation, then through sampling in 1: 3, promptly obtain the progressive signals that vertical resolution is 833 row, sampling in promptly 4: 3 every two capable modes of getting delegation; Two of odd evens that at last progressive signal that obtains are divided into 416.5 row, two of this odd evens are two of outputs after the linear rows interpolation;

2) field frequency promotes and adopts following method to carry out:

A, b, four implementations of e, f: interpolation obtains 416.5 two interlace signal A ' 1, the B ' 1 that go through linear rows by A1, B1 two field signals, and A ' 1 is output a field signal, and B ' 1 is output b field signal; Interpolation obtains 416.5 two interlace signal A ' 2, the B ' 2 that go through linear rows for A2, B2 two field signals, and A ' 2 is output e field signal, and B ' 2 is output f field signal;

Two of the implementation that c, d are two: c, d are the interpolation field, A1, A2 two field signals carry out the average computing, adopt 3 * 3 windows, 3 direction (α then, β, γ) 6 point self-adapted motion compensated filterings go the interlacing algorithm to form the frame signal of 625 row, generate 833 frame signals of going by sampling in 4: 3, frame signal is split into 416.5 two interlace signals of odd even of going, get strange field and be output c field signal; B1, B2 two field signals carry out the average computing, adopt 3 * 3 windows, 3 direction (α then, β, γ) 6 point self-adapted motion compensated filterings go the interlacing algorithm to form the frame signal of 625 row, generate the frame signal of 833 row by sampling in 4: 3, frame signal is split into 416.5 two interlace signals of odd even of going, gets the idol field and be output d field signal.

2. Digital Television 75Hz linear rows according to claim 1 interpolation and field frequency method for improving is characterized in that, described field frequency promotes and can also adopt following method to carry out:

A, b, four implementations of e, f: interpolation obtains 416.5 two interlace signal A ' 1 that go through linear rows by A1, B1 two field signals, and B ' 1, and A ' 1 is output a field signal, and B ' 1 is output b field signal; Interpolation obtains 416.5 two interlace signal A ' 2, the B ' 2 that go through linear rows for A2, B2 two field signals, and A ' 2 is output e field signal, and B ' 2 is output f field signal;

Two implementations of c, d: the c field is by B1 field 3 * 3 windows, 3 direction (α, β, γ) 6 point self-adapted motion compensated filterings go the interlacing algorithm to form the frame signal of 625 row, generate the frame signal of 833 row then through sampling in 4: 3, frame signal is split into 416.5 two interlace signals of odd even of going, gets strange field and obtain c field output signal; The d field is by A2 field 3 * 3 windows, 3 direction (α, beta, gamma) 6 point self-adapted motion compensated filterings go the interlacing algorithm to form the frame signal of 625 row, generate 833 frame signals of going through sampling in 4: 3 then, frame signal is split into 416.5 two interlace signals of odd even of going, gets the idol field and obtain d field output signal.

3. Digital Television 75Hz linear rows according to claim 1 interpolation and field frequency method for improving is characterized in that, described field frequency promotes and also can also adopt following method to carry out:

A field implementation: the interlace signal that obtains 416.5 row through sampling in 4: 3 by the A1 field signal is output a field signal;

Two implementations of b, c: obtain 416.5 interlace signals of going by the B1 field signal through sampling in 4: 3, this interlace signal while is as the output signal of two of b, c;

Two implementations of d, e: obtain 416.5 interlace signals of going by the A2 field signal through sampling in 4: 3, this interlace signal while is as the output signal of two of d, e;

F field implementation: the interlace signal that obtains 416.5 row through sampling in 4: 3 by the B2 field signal is output f field signal.

4. according to claim 1 or 2 or 3 described Digital Television 75Hz linear rows interpolations and field frequency method for improving, it is characterized in that described 3 * 3 windows, 3 directions (α, beta, gamma) 6 point self-adapted motion compensated filterings go the interlacing algorithm to be:

1) establish size and represent with I, and size is N * M for the image that N * M/2 interlaced video image process is interlaced to behind the progressive scanning conversion; Arbitrary position P at image _Ij(wherein, i=1 ..., N, j=1 ..., the I (P of pixel M) _Ij) expression, i wherein, j is respectively the coordinate of row and column; When i is odd number, represent current from strange field signal; When i is even number, represent current from even field signal;

2) establish I (P _Ij) be the image border point, this point must be on the direction of its gradient minimum, promptly in the gray-value variation minimum of image edge direction epigraph; Get with an I (P _Ij) be 3 * 3 windows at center, definable I (P _Ij) three directions: α direction, β direction and γ direction, and can obtain an I (P _Ij) at α, the gradient on these three directions of beta, gamma is:

3) absolute value of gradient as from the foregoing, | _αF|, | _βF| and | _γThe direction of f| minimum is exactly that current frame image is at an I (P _Ij) edge direction located;

So the output of adaptive motion compensated filter can be defined as: $g\left(P_{\mathrm{ij}}\right)=\frac{1}{2}\{f_{\mathrm{up}}+f_{\mathrm{down}}\}----\left(2\right)$

Perhaps

g(P _ij)＝Med{f _up，f _down} (3)

Wherein

f _Up=I (P _{(i+1) (j-1)}), f _Down=I (P _{(i-1) (j+1)}) when | _αF| is a minimum value

f _Up=I (P _{(i) (j-1)}), f _Down=I (P _{(i) (j+1)}) when | _βF| is minimum value (4)

f _Up=I (P _{(i-1) (j-1)}, f _Down=I (P _{(i+1) (j+1)}) when | _γF| is a minimum value

By 3 * 3 windows, 3 direction (α; β; γ) 6 point self-adapted motion compensated filterings remove the progressive video signal behind the interlacing algorithm; can protect the edge of image characteristic well; so just can the modifying factor image motion and cause differences strange, idol two field signals, thus the edge of image blooming reduced.

5. according to claim 1 or 2 or 3 described Digital Television 75Hz linear rows interpolations and field frequency method for improving, it is characterized in that sampling algorithm was in described 4: 3:

1) size of establishing image is N * M, Il, I2, I3, I4 are the line displays of received image signal, O1, O2, O3, O4, O5 are the line displays of output image signal after sampling in 4: 3, and L1, L2, L3 insert row: get I respectively on I1, I2, I3, the I4 of input picture is capable _Ij, I _{I (j+1)}, I _{I (j+2)}, I _{I (j+3)}Four points (wherein, i=1 ..., N, j=1 ..., M); Get L respectively on three insertion row _{I (j+3)}, L _{I (j+6)}, L _{I (j+9)}3 points; Get O respectively on five output row _Ij, O _{I (j+1)}, O _{I (j+2)}, O _{I (j+3)}, O _{I (j+4)}5 points;

2) linear insertion four lines between two row of original image, L1, L2, L3 adopt linear interpolation to draw, and therefore have

L _i(j+3)＝(I _ij+3I _i(j+1))/4

L _i(j+6)＝(I _i(j+1)+I _i(j+2))/2 (5)

L _i(j+9)＝(3I _i(j+2)+I _i(j+3))/4

3) extract delegation every two row in the frame that after linearity is inserted row, obtains, obtain the output image of sampling in final 4: 3; Its pass is:

O _ij＝I _ij

O _i(j+1)＝L _(j+3)＝(I _ij+3I _i(j+1))/4

O _i(j+2)＝L _i(j+6)＝(I _i(j+1)+I _i(j+2))/2 (6)

O _i(j+3)＝L _i(j+9)＝(3I _i(j+2)+I _i(j+3))/4

O _i(j+4)＝I _i(j+3)

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