CN101711000A - Coding scheme based on acquisition of three primary colors with widest sensible color gamut - Google Patents

Abstract

The invention relates to digital television and wide color gamut theory and technology, in particular to a coding scheme based on the acquisition of three primary colors with the widest sensible color gamut and corresponding to ITU-R BT.1361. The coding scheme based on the acquisition of the three primary colors with the widest sensible color gamut uses an ergodic point taking calculation method which comprises the following steps: taking values at random in a range of -0.25 to 1.33 respectively by gamma correction input signals LR, LG and LB; and comparing a color formed by each group of taken values with a tongue-shaped spectrum curve to obtain all sensible colors; and deducing to obtain the three primary colors with the widest sensible color gamut corresponding to the ITU-R BT.1361 according to the characteristics of a color bar signal, and deducing the coding realization scheme based on the three primary colors with the widest sensible color gamut. The invention is mainly applied to compatible data transmission in a color television system.

Description

But based on the encoding scheme of obtaining the wideest perception colour gamut three primary colors

Technical field

The present invention relates to Digital Television, wide colour gamut theory and technology.Specifically, but relate to corresponding to ITU-R BT.1361 based on the encoding scheme of obtaining the wideest perception colour gamut three primary colors.

Technical background

Along with developing rapidly of modern science and technology and industry, in recent years multiple new display spare and Display Technique continue to bring out, except that traditional cathode ray tube (CRT), LCD (LCD), plasma scope (PDP), digital optical processor (DLP), Liquiid crystal on silicon (lcos) display (LCoS), back light source in LED LCD multiple new display spares such as (LED-LCD) be practicability or succeeded in developing.Aspect display mode, except that direct viewing type, front projection, back projection and laser projection demonstration etc. have also dropped into practicality.These novel high-end display devices and display mode adopt different materials, device and technology based on different principle, and the colour reproduction ability is strengthening, and performance is improving, and some " following type " displays also will emerge in large numbers.Also there has been more and more higher requirement the consumption market to display effect on the other hand, only promotes clearness to satisfy the requirement of people to the true reappearance scene, and the colour reproduction ability is also becoming the important indicator of weighing the display display effect.

At present general television system is still based on the scientific and technological achievement in one's early years, press CRT characteristic selecting system parameter, limit the nature existence, manually can synthesize or calculate the function generation, and can be visually perceived thereby colour gamut width that television system should be transmitted and reappear, make the not enough vision of present colour gamut coverage rate can experience 40% of gamut range.Can not satisfy satellite DTV (Digital Television), wired DTV and ground DTV and start broadcasting, Digital Television is replacing simulated television, and digital television techniques has been used for the requirement of film making and digital camera etc.And progress, computer and the Digital Signal Processing of present age shooting and imaging technique go deep into digital TV field and have made and widen the Digital Television colour gamut and become possibility.Given this, make up the transmission of the principle of wide colour gamut television system, wide colour gamut TV signal and reproduction mode etc., become the hot subject of present international academic community and the new growth point of related industry circle, wide colour gamut TV tech shows for digital tv encoder of future generation, transmission and reception can produce significant impact.

At present, relevant International Standards Organization makes some wide gamut standards in succession.Wherein, ITU-R BT.1361 and IEC61966 series standard are the wide gamut standards towards Digital Video System.The former is a target color gamut with the Pointer colour gamut, regulation red-green-blue gamma correction input signal L _R, L _G, L _BDynamic range be [0.25,1.33], adopt positive and negative asymmetric gamma correction curve to realize compression to wide colour gamut vision signal.The xvYCC color space of latter's standard is unrestricted to the amplitude range of input signal, adopts the gamma correction curve of positive and negative symmetry, realizes wide colour gamut transmission of video signals by the method that enlarges available quantizing range.IEC 61966 has also worked out standard respectively to the color management of video camera, CRT, LCD, PDP etc.

ITU-R BT.1361 is the wide gamut standards at video system, is target color gamut with the Pointer colour gamut, regulation red-green-blue gamma correction input signal L _R, L _G, L _BDynamic range be [0.25,1.33].Obviously as signal L _R, L _G, L _BIn this scope during random value, some color of being constructed will be positioned at outside the tongue type curve of spectrum, is the invisible color of human eye respectively.

Summary of the invention

For overcoming the deficiencies in the prior art, the objective of the invention is to avoid as signal L _R, L _G, L _BIn this scope during random value, some color of being constructed will be positioned at outside the tongue type curve of spectrum, is the invisible color of human eye, but realizes the transmission and the representation of the wideest perception colour gamut of ITU-RBT.1361 respectively.

The technical solution used in the present invention is: use traversal to get a Calculation Method, even red-green-blue gamma correction input signal L _R, L _G, L _BRespectively [0.25,1.33] the interior random value of scope, but relatively obtain all perception colours with whenever getting the colour and the tongue type curve of spectrum that class value structure obtains, and according to the characteristics of color bar signal, but obtain three primary colours of the wideest perception colour gamut of corresponding ITU-R BT.1361 through derivation, but and derive coding implementation based on three primary colours of the wideest aforementioned perception colour gamut.

The described gamma correction input signal L that makes _R, L _G, L _BRandom value in [0.25,1.33] scope respectively, but relatively to obtain all perception colours be to get L with whenever getting the colour that class value structure obtains and the tongue type curve of spectrum _R, L _G, L _BThe traversal step-length be 0.01, test 159 altogether ³Plant colored, detect every kind of colour and whether be positioned at tongue type curve of spectrum institute area surrounded, if, but illustrate that then this colour is a human eye perception colour, write down this colour and calculate its u ' v ' coordinate in three-dimensional color space L*u ' v ', informal voucher and secret note correspond respectively to luminance signal E ' _YMaximum and minimum value, blue and yellow signal corresponds respectively to blue degree signal E ' _CBMaximum and minimum value, red and cyan then corresponds respectively to red degree signal E ' _CRMaximum and minimum value, respectively relatively by scope [0.25,1.33] but the brightness signal value and the carrier chrominance signal value of all aware colors that limit can get its minimum and maximum value, result such as table 1 are listed:

Table 1. luminance and chrominance information maximum, minimum value and corresponding six kinds of colors and chromaticity coordinate thereof

According to the result shown in the table 1, can get blue, red primary and Huang, blue or green complementary color.

But described three primary colours that obtain the wideest perception colour gamut of corresponding ITU-R BT.1361 through derivation are, use traversal to get a Calculation Method and obtain indigo plant, red primary and Huang, blue or green complementary color chromaticity coordinate, adopt mapping method: at first under u ' v ' coordinate system, determine respectively corresponding to " E ' _CB_ max " " blueness ", corresponding to " E ' _CB_ min " " yellow ", corresponding to " E ' _CR_ max " " redness ", corresponding to " E ' _CR_ min " " cyan "; the intersection point of ray " indigo plant-green grass or young crops " and " red-Huang " is " green "; and the intersection point of ray " green-D65 " and " blue-red " is " product look "; thus; can get green primary and the coordinate of complementary color product look in u ' v ' coordinate system thereof; computed information is respectively (0.1038,0.5830) and (0.3594,0.2717), continue to use traversal method, [0.25,1.33] in the scope, find respectively and " green " (0.1038,0.5830), " product look " (0.3594,0.2717) value that chromaticity coordinate is identical, so learn the L of these two kinds of colors _R, L _G, L _BValue.

But described derivation based on the coding implementation of three primary colours of the wideest aforementioned perception colour gamut is, but with the xyz chromaticity coordinate of three primary colours and the light source of the wideest above-mentioned perception colour gamut, the rgb space of derivation to the color space transformation matrix in xyz space as the formula (1):

$\left[\begin{array}{c}X\\ Y\\ Z\end{array}\right]=\left[\begin{array}{ccc}0.4545& 0.3147& 0.1822\\ 0.1665& 0.7857& 0.0478\\ 0.0082& 0.0097& 1.0715\end{array}\right]\left[\begin{array}{c}R\\ G\\ B\end{array}\right]---\left(1\right)$

According to formula (1), brightness and two carrier chrominance signals are:

$\left\{\begin{array}{c}Y=0.1665R+0.7857G+0.0478B\\ R-Y=0.8335R-0.7857G-0.0478B\\ B-Y=-0.1665R-0.7857G+0.9522B\end{array}\right.---\left(2\right)$

With the new three primary colors of gained of the present invention, in the color matching ratio, color bar signal is as shown in table 3:

The new three primary colors color bar signal color matching ratio of table 3.

L _R, L _G, L _BBecome E ' through the gamma correction correspondence _R, E ' _G, E ' _BBased on new three primary colors, usefulness formula (2) coding color bar signal, its brightness and two chrominance component signals are as shown in table 4:

Table 4. is by the new three primary colors color bar signal gained luminance and chrominance information of formula (2) coding

E ' in the table 4 _R-E ' _YThe peak-to-peak value of signal is 1.667, and the present invention determines signal E ' _CRThe compressed coefficient be 1.667;

In like manner, signal E ' _CBThe compressed coefficient be 1.9044;

Based on above-mentioned analysis and formula (2), the present invention adopts to encode shown in coding staff formula (3) and obtains transmission signals E ' _Y, E ' _CB, E ' _CR:

$\left\{\begin{array}{c}{E}_Y^{\′}=0.1665E_R^{\′}+0.7857E_G^{\′}+0.0478E_B^{\′}\\ E_{\mathrm{CR}}^{\′}=0.5E_R^{\′}-0.4713E_G^{\′}-0.0287E_B^{\′}\\ E_{\mathrm{CB}}^{\′}=-0.0874E_R^{\′}-0.4126E_G^{\′}+0.5E_B^{\′}\end{array}\right.---\left(3\right)$

Brightness and chrominance component signal based on the color bar signal of new three primary colors that formula (3) coding obtains are as shown in table 5:

New three primary colors color bar signal formula (3) coding gained brightness of table 5. and chrominance component signal

The present invention presses the luminance signal E ' of table 5 coding _YDynamic range be [0,1], carrier chrominance signal E ' _CB, E ' _CRDynamic range be [0.5,0.5], the conventional linear quantization method that this dynamic range signal can provide with ITU-R BT.709 quantizes E ' _YWill be quantized to [16,235], E ' _CB, E ' _CRWill be quantized to [16,240], compatible transmission in existing vitascan.

The present invention has following technique effect:

The present invention is based on ITU-R BT.1361, obtain the visible maximum gamut of video system human eye in the ITU-R BT.1361 prescribed limit with traversal method, by the color bar signal that constitutes by three primary colors and complementary color thereof, derived new three primary colors that should wide colour gamut, and then provided the brightness, the carrier chrominance signal coding that adopt new three primary colors and realize.

Description of drawings

Fig. 1 ITU-R BT.1361 the wideest attainable colour gamut and with the T.709 contrast of conventional colour gamut of ITU-R B.

Embodiment

The present invention is based on ITU-R BT.1361 standard, but derive the wideest perception colour gamut and coding implementation that should standard.

ITU-R BT.1361 is the wide gamut standards at video system, is target color gamut with the Pointer colour gamut, regulation red-green-blue gamma correction input signal L _R, L _G, L _BDynamic range be [0.25,1.33].Obviously as signal L _R, L _G, L _BIn this scope during random value, some color of being constructed will be positioned at outside the tongue type curve of spectrum, is the invisible color of human eye respectively.

Be the wideest perception colour gamut that obtains scope [0.25,1.33] but define, the present invention uses traversal to get a Calculation Method, even L _R, L _G, L _BRespectively [0.25,1.33] the interior random value of scope, but relatively obtain all perception colours with whenever getting the colour and the tongue type curve of spectrum that class value structure obtains, and according to the characteristics of color bar signal, but obtain three primary colours of the wideest perception colour gamut of corresponding ITU-R BT.1361 through derivation, and derive coding implementation based on new three primary colors.

Use the three primary colors and the encoding scheme thereof of the present invention's proposition, but can realize the transmission and the representation of the wideest perception colour gamut of ITU-R BT.1361.

Further specify the present invention below in conjunction with drawings and Examples.

The present invention gets L in data computation _R, L _G, L _BThe traversal step-length be 0.01, test 159 altogether ³Plant colour, detect every kind of colour and whether be positioned at tongue type curve of spectrum institute area surrounded.If, but illustrate that then this colour is a human eye perception colour, write down this colour and calculate its u ' v ' coordinate in three-dimensional color space L*u ' v '.Test result shows, altogether 159 ³Plant in the test color, but have 81.59% to be the human eye aware colors.

Vitascan is based on the principle of three primary colours and additive color mixture principle, and the delta-shaped region that is limited by three primary colours on the chromatic diagram is the maximum gamut that vitascan can realize.Color bar signal based on this design generally is used for vitascan design and test.Usually color bar signal is by red (R), green (G), blue (B) three primary colours and complementary color (green grass or young crops, product, Huang) thereof and an informal voucher and a secret note composition.In these eight kinds of colors, informal voucher and secret note correspond respectively to luminance signal E ' _YMaximum and minimum value, blue and yellow signal corresponds respectively to blue degree signal E ' _CBMaximum and minimum value, red and cyan then corresponds respectively to red degree signal E ' _CBMaximum and minimum value.Based on above-mentioned analysis, respectively relatively by scope [0.25,1.33] but the brightness signal value and the carrier chrominance signal value of all aware colors that limit can get its minimum and maximum value, result such as table 1 are listed.

Table 1. luminance and chrominance information maximum, minimum value and corresponding six kinds of colors and chromaticity coordinate thereof

Table 1 has provided signal E ' _Y, E ' _CB, E ' _CRMinimum and maximum value, the chromaticity coordinate in the color of their correspondences and the u ' v ' coordinate system thereof.According to the experimental result shown in the table 1, can get blue, red primary and Huang, blue or green complementary color.

For obtaining another green primary, the present invention adopts mapping method.At first under u ' v ' coordinate system, determine respectively corresponding to " E ' _CB_ max " " blueness ", corresponding to " E ' _CB_ min " " yellow ", corresponding to " E ' _CR_ max " " redness ", corresponding to " E ' _CR_ min " " cyan ", the intersection point of ray " indigo plant-green grass or young crops " and " red-Huang " is " green ", and the intersection point of ray " green-D65 " and " blue-red " is " product look ".Like this, can get green primary and the coordinate of complementary color product look in u ' v ' coordinate system thereof, computed information is respectively (0.1038,0.5830) and (0.3594,0.2717).

The delta-shaped region that is limited by above-mentioned gained three primary colors is the ITU-R BT.1361 standard of following, based on the video system of the principle of three primary colours the wideest attainable colour gamut, shown in chain-dotted line triangle among Fig. 1, its colour gamut coverage rate is 60.65%.Also compared the conventional colour gamut that ITU-R BT.709 standard provides among Fig. 1, shown in broken line triangle among Fig. 1, its colour gamut coverage rate is 33.24%.

Because of green and the product chromaticity coordinates that finds in u ' v ' coordinate system with above-mentioned reflection method do not comprise monochrome information, so still can not obtain the L of these two kinds of colors according to its u ' v ' coordinate _R, L _G, L _BValue.For this reason, the present invention continues to use traversal method, in [0.25,1.33] scope, finds respectively and " green " (0.1038,0.5830), the identical value of " product look " (0.3594,0.2717) chromaticity coordinate, so learn the L of these two kinds of colors _R, L _G, L _BValue.The result shows: corresponding with these two kinds of color chromaticity coordinates, a class value is respectively arranged.

In sum, as seen the human eye that the present invention derives meets ITU-R BT.1361 standard, has the peak signal dynamic range, and the color bar signal parameter that characterizes television system primary colours, complementary color and muted color is as shown in table 2.

Table 2. human eye is visible, meet ITU-R BT.1361 standard, have the color bar signal parameter of wide colour gamut

According to the listed the present invention of table 2 derive,, new three primary colors with the wideest perception colour gamut corresponding with ITU-R BT.1361, the present invention further provides a kind of coding implementation method.This method is organized new three primary colors based on this, realizes by following new luminance and chrominance information encoding equtions.

The present invention is light source with D65, with the xyz chromaticity coordinate of above-mentioned new three primary colors and D65, the rgb space of derivation to the color space transformation matrix of XYZ space as the formula (1):

$\left[\begin{array}{c}X\\ Y\\ Z\end{array}\right]=\left[\begin{array}{ccc}0.4545& 0.3147& 0.1822\\ 0.1665& 0.7857& 0.0478\\ 0.0082& 0.0097& 1.0715\end{array}\right]\left[\begin{array}{c}R\\ G\\ B\end{array}\right]---\left(1\right)$

According to formula (1), brightness and two carrier chrominance signals are:

$\left\{\begin{array}{c}Y=0.1665R+0.7857G+0.0478B\\ R-Y=0.8335R-0.7857G-0.0478B\\ B-Y=-0.1665R-0.7857G+0.9522B\end{array}\right.---\left(2\right)$

With the new three primary colors of gained of the present invention, in the color matching ratio, color bar signal is as shown in table 3:

The new three primary colors color bar signal color matching ratio of table 3.

L _R, L _G, L _BBecome E ' through gamma correction _R, E ' _G, E ' _BBased on new three primary colors, usefulness formula (2) coding color bar signal, its brightness and two chrominance component signals are as shown in table 4:

Table 4. is by the new three primary colors color bar signal gained luminance and chrominance information of formula (2) coding

E ' in the table 4 _R-E ' _YThe peak-to-peak value of signal is 1.667, and the present invention determines signal E ' _CRThe compressed coefficient be 1.667.In like manner, signal E ' _CBThe compressed coefficient be 1.9044.

Based on above-mentioned analysis and formula (2), the present invention adopts to encode shown in coding staff formula (3) and obtains transmission signals E ' _Y, E ' _CR, E ' _CB:

$\left\{\begin{array}{c}{E}_Y^{\′}=0.1665E_R^{\′}+0.7857E_G^{\′}+0.0478E_B^{\′}\\ E_{\mathrm{CR}}^{\′}=0.5E_R^{\′}-0.4713E_G^{\′}-0.0287E_B^{\′}\\ E_{\mathrm{CB}}^{\′}=-0.0874E_R^{\′}-0.4126E_G^{\′}+0.5E_B^{\′}\end{array}\right.---\left(3\right)$

Brightness and chrominance component signal based on the color bar signal of new three primary colors that formula (3) coding obtains are as shown in table 5:

New three primary colors color bar signal formula (3) coding gained brightness of table 5. and chrominance component signal

The present invention presses the luminance signal E ' of table 5 coding _YDynamic range be [0,1], carrier chrominance signal E ' _CR, E ' _CBDynamic range be [0.5,0.5].This dynamic range signal can quantize E ' with the conventional linear quantization method that ITU-R BT.709 provides _YWill be quantized to [16,235], E ' _CR, E ' _CBWill be quantized to [16,240], compatible transmission in existing vitascan.

Beneficial effect

Existing general conventional colour gamut and human eye visual gamut are far apart, ITU-R BT.1361 is the wide gamut standards towards Digital Video System, with the Pointer colour gamut is target color gamut, the dynamic range of regulation gamma correction input signal is [0.25,1.33], adopt the compression of positive and negative asymmetric gamma correction curve realization to wide colour gamut vision signal.The present invention is based on ITU-R BT.1361, obtain the visible maximum gamut of video system human eye in the ITU-R BT.1361 prescribed limit with traversal method, by the color bar signal that constitutes by three primary colors and complementary color thereof, derived new three primary colors that should wide colour gamut, and then provided the brightness, the carrier chrominance signal coding that adopt new three primary colors and realize.

New three primary colors that employing the present invention proposes and brightness, carrier chrominance signal encoding equtions, the colour gamut coverage rate of digital television system transmission colour gamut is doubled approximately, carry to 60.65% by 33.24% of existing conventional colour gamut, realize that but ITU-R BT.1361 allows the maximum perception colour gamut of dynamic range of signals, and make the luminance and chrominance information of coding be able to compatible transmission in existing vitascan.

The three primary colors of digital color TV systems are defined as the three primary colors that the present invention proposes, and its chromaticity coordinate is as shown in table 2.Carry out gamma correction to importing wide colour gamut colour TV signal by the gamma correction method that ITU-R BT.1361 stipulates, right back-pushed-type (3) carries out the analog component signal coding to the primary colour signal after proofreading and correct, obtain luminance and chrominance information, again through traditional digital coding, can be in existing vitascan compatible transmission makes the gamut range maximum of the colour TV signal that receiving terminal obtains can reach 60.65%.

Claims (4)

1. but one kind based on the encoding scheme of obtaining the wideest perception colour gamut three primary colors, it is characterized in that, uses traversal to get a Calculation Method, even red-green-blue gamma correction input signal L _R, L _G, L _BRespectively [0.25,1.33] the interior random value of scope, but relatively obtain all perception colours with whenever getting the colour and the tongue type curve of spectrum that class value structure obtains, and according to the characteristics of color bar signal, but obtain three primary colours of the wideest perception colour gamut of corresponding ITU-R BT.1361 through derivation, but and derive coding implementation based on three primary colours of the wideest aforementioned perception colour gamut.

2. but according to claim 1ly it is characterized in that the described red-green-blue gamma correction input signal L that makes based on the encoding scheme of obtaining the wideest perception colour gamut three primary colors _R, L _G, L _BRandom value in [0.25,1.33] scope respectively, but relatively to obtain all perception colours be to get L with whenever getting the colour that class value structure obtains and the tongue type curve of spectrum _R, L _G, L _BThe traversal step-length be 0.01, test 159 altogether ³Plant colour, detect every kind of colour and whether be positioned at tongue type curve of spectrum institute area surrounded, if, but illustrate that then this colour is a human eye perception colour, write down this colour and calculate it at three-dimensional color space L ^*U ' v ' coordinate among u ' v ', informal voucher and secret note correspond respectively to luminance signal E ' _YMaximum and minimum value, blue and yellow signal corresponds respectively to blue degree signal E ' _CBMaximum and minimum value, red and cyan then corresponds respectively to red degree signal E ' _CRMaximum and minimum value, respectively relatively by scope [0.25,1.33] but the brightness signal value and the carrier chrominance signal value of all aware colors that limit can get its minimum and maximum value, result such as table 1 are listed:

Table 1. luminance and chrominance information maximum, minimum value and corresponding six kinds of colors and chromaticity coordinate thereof

According to the result shown in the table 1, can get blue, red primary and Huang, blue or green complementary color.

3. but according to claim 1 based on the encoding scheme of obtaining the wideest perception colour gamut three primary colors, it is characterized in that, but described three primary colours that obtain the wideest perception colour gamut of corresponding ITU-R BT.1361 through derivation are, use traversal to get a Calculation Method and obtain indigo plant, red primary and Huang, blue or green complementary color chromaticity coordinate, adopt mapping method: at first under u ' v ' coordinate system, determine respectively corresponding to " E ' _{CB_max}" " blueness ", corresponding to " E ' _{CB_min}" " yellow ", corresponding to " E ' _{CR_max}" " redness ", corresponding to " E ' _{CR_min}" " cyan "; the intersection point of ray " indigo plant-green grass or young crops " and " red-Huang " is " green "; and the intersection point of ray " green-D65 " and " blue-red " is " product look "; thus; can get green primary and the coordinate of complementary color product look in u ' v ' coordinate system thereof; computed information is respectively (0.1038,0.5830) and (0.3594,0.2717), continue to use traversal method, [0.25,1.33] in the scope, find respectively and " green " (0.1038,0.5830), " product look " (0.3594,0.2717) value that chromaticity coordinate is identical, so learn the L of these two kinds of colors _R, L _G, L _BValue.

4. but according to claim 1 based on the encoding scheme of obtaining the wideest perception colour gamut three primary colors, it is characterized in that, but described derivation based on the coding implementation of three primary colours of the wideest aforementioned perception colour gamut is, but with the xyz chromaticity coordinate of three primary colours and the light source of the wideest above-mentioned perception colour gamut, the rgb space of derivation to the color space transformation matrix of XYZ space as the formula (1):

$\left[\begin{array}{c}X\\ Y\\ Z\end{array}\right]=\left[\begin{array}{ccc}0.4545& 0.3147& 0.1822\\ 0.1665& 0.7857& 0.0478\\ 0.0082& 0.0097& 1.0715\end{array}\right]\left[\begin{array}{c}R\\ G\\ B\end{array}\right]---\left(1\right)$

According to formula (1), brightness and two carrier chrominance signals are:

$\left\{\begin{array}{c}Y=0.1665R+0.7857G+0.0478B\\ R-Y=0.8335R-0.7857G-0.0478B\\ B-Y=-0.1665R-0.7857G+0.9522B\end{array}\right.---\left(2\right)$

With the new three primary colors of gained of the present invention, in the color matching ratio, color bar signal is as shown in table 3:

The new three primary colors color bar signal color matching ratio of table 3.

L _R, L _G, L _BBecome E ' through the gamma correction correspondence _R, E ' _G, E ' _BBased on new three primary colors, usefulness formula (2) coding color bar signal, its brightness and two chrominance component signals are as shown in table 4:

Table 4. is by the new three primary colors color bar signal gained luminance and chrominance information of formula (2) coding

E ' in the table 4 _R-E ' _YThe peak-to-peak value of signal is 1.667, and the present invention determines signal E ' _CRThe compressed coefficient be 1.667;

In like manner, signal E ' _CBThe compressed coefficient be 1.9044;

Based on above-mentioned analysis and formula (2), the present invention adopts to encode shown in coding staff formula (3) and obtains transmission signals E ' _Y, E ' _CB, E ' _CR:

$\left\{\begin{array}{c}{E}_Y^{\′}={0.1665E}_R^{\′}+0.7857E_G^{\′}+0.0478E_B^{\′}\\ E_{\mathrm{CR}}^{\′}=0.5E_R^{\′}-0.4713E_G^{\′}-0.0287E_B^{\′}\\ E_{\mathrm{CB}}^{\′}=-{0.0874E}_R^{\′}-{0.4126E}_G^{\′}+{0.5E}_B^{\′}\end{array}\right.---\left(3\right)$

Brightness and chrominance component signal based on the color bar signal of new three primary colors that formula (3) coding obtains are as shown in table 5:

New three primary colors color bar signal formula (3) coding gained brightness of table 5. and chrominance component signal

Press the luminance signal E ' of table 5 coding _YDynamic range be [0,1], carrier chrominance signal E ' _CB, E ' _CRDynamic range be [0.5,0.5], the conventional linear quantization method that this dynamic range signal can provide with ITU-R BT.709 quantizes E ' _YWill be quantized to [16,235], E ' _CB, E ' _CRWill be quantized to [16,240], compatible transmission in existing vitascan.

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