CN115083360B - Field sequence time color mixing algorithm - Google Patents
Field sequence time color mixing algorithm Download PDFInfo
- Publication number
- CN115083360B CN115083360B CN202110260064.5A CN202110260064A CN115083360B CN 115083360 B CN115083360 B CN 115083360B CN 202110260064 A CN202110260064 A CN 202110260064A CN 115083360 B CN115083360 B CN 115083360B
- Authority
- CN
- China
- Prior art keywords
- value
- field
- scale value
- gray scale
- gray
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
- G09G3/36—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals
- G09G3/3607—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals for displaying colours or for displaying grey scales with a specific pixel layout, e.g. using sub-pixels
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
- G09G3/3406—Control of illumination source
- G09G3/3413—Details of control of colour illumination sources
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
- G09G3/36—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Control Of Indicators Other Than Cathode Ray Tubes (AREA)
Abstract
The invention discloses a field sequence time color mixing algorithm, which specifically comprises the following steps: s1, calculating EL and EH in a current field sequence; s2, judging whether the EL or the EH is accepted, if so, calculating Rd, and converting the Rd serving as an image data gray level value into a gray level voltage; otherwise, entering S3; s3, adjusting T5, and calculating EL1, EH1 and Rd1; s4, judging whether the EL1 and the EH1 are accepted, and if so, converting the Rd1 serving as an image data gray level value into a gray level voltage; otherwise, entering S5; and S5, adjusting T4, calculating Rd2, and converting the Rd2 serving as an image data gray level value into a gray level voltage. According to the passively input gray scale value, the gray scale value of the current field, the backlight duration and the relative position of the backlight starting moment are adjusted to form an equivalent gray scale value, and if the equivalent gray scale value is close to or equal to the target gray scale value, the smaller the error is, the less obvious or no color cast phenomenon is; through the process, the equivalent gray-scale value can be close to or equal to the target gray-scale value, so that the color cast is greatly reduced.
Description
Technical Field
The invention belongs to the technical field of liquid crystal display, and particularly relates to a field sequence time color mixing algorithm.
Background
In the field sequential time color mixing, because the imaging has a time sequence, at least 3 sub-field arrangements are needed for finishing the imaging of the same frame of the space color mixing phase, the data of RGB three fields is prepared according to the theoretical data, and then the backlight of the RGB three fields is carried out, and the three fields are in one-to-one correspondence with each other.
However, since under the field sequential display logic, the time of each frame of picture, if 180HZ is taken as an example, is only 5.56 milliseconds per frame; taking 240HZ as an example, only 4.17 milliseconds; in such a short time, if the liquid crystal scanning drive is implemented to implement data transfer and then backlight illumination is performed, the backlight illumination time may be short. In addition, in the case where the backlight illumination time is short, a very high demand is imposed on a driving chip for liquid crystal.
If the conventional backlight method is adopted, i.e. the backlight is normally bright, the following situation occurs: the row of pixels which have realized the data transmission keeps the state of the previous frame before realizing the data transmission; but its color is already the data of the present frame. However, since the data transfer of the liquid crystal is time-critical, the liquid crystal pixels perform the data transfer from the first row to the last row, each row performing the data transfer at a different time point. Therefore, the following problems inevitably occur: although the backlight is normally bright, the brightness increases; the time of the data obtained in each line is different, so that the data of the picture of the previous frame receives the illumination of the current frame, and then the illumination of the current frame is received after the data of the current frame is finished; as a result, the total illumination time of the frame is extended, but is divided into two time segments, and the data of the two time segments are different, wherein the first half is the data of the previous frame, and the second half is the data of the next frame; the data of this frame also affects the image of the next frame.
Disclosure of Invention
In order to solve the above problems, the present invention provides a field sequential temporal color mixing algorithm, which greatly reduces the color cast phenomenon while satisfying the requirements of high refresh rate and high brightness, thereby improving the display quality of images and video imaging.
The technical scheme adopted by the invention is as follows:
a field sequence time color mixing algorithm is implemented according to the following steps:
s1, calculating EL and EH in a current field sequence;
s2, judging whether the EL or the EH is accepted, if so, calculating a Rd, and converting the Rd serving as an image data gray level value into a gray level voltage; otherwise, entering S3;
s3, adjusting T5, and calculating EL1, EH1 and Rd1;
s4, judging whether the EL1 and the EH1 are accepted, and if so, converting the Rd1 serving as an image data gray-scale value into a gray-scale voltage; otherwise, entering S5;
s5, adjusting T4, calculating Rd2, and converting the Rd2 serving as an image data gray-scale value into a gray-scale voltage;
wherein EL and EH are respectively the percentage of dark part and the percentage of bright part in the area which can not be represented in the gray scale; rd is the adjusted digital gray scale value of a certain primitive in a certain pixel; t5 is translation time of the subfield backlight starting moment; EL1, EH1, and Rd1 are the percentage of dark portion, the percentage of bright portion, and the digital gray scale value of a certain element in a certain pixel in the area that cannot be represented after T5 adjustment; EL2, EH2, and Rd2 are the percentage of dark portion, the percentage of bright portion, and the digital gray scale value of a certain primitive in a certain pixel in the area that cannot be represented after T4 adjustment; t4 is the time for increasing or decreasing the backlight of the current sub-field relative to the duration of each field of backlight; t5 is the subfield backlight start time shift time.
Preferably, the S1-S5 are repeated three times until the R, G, and B fields of the current frame are completed.
Preferably, EL and EH in the current field sequence are calculated in S1, specifically, by the following formula:
in the above formula, rd is the current digital gray scale value of a certain primitive of a certain pixel in a certain field; bd is the digital gray-scale value of the previous element of the pixel corresponding to the previous field of the corresponding Rd, and T1 is the duration of each field of backlight in the field sequence; t3 is the data transmission time for completing one line; t4 is the time for increasing or decreasing the backlight of the current sub-field relative to T1; d is the range of the whole gray scale value; m is the current row number.
Preferably, in S2, it is determined whether the EL or the EH is accepted, if yes, rd is calculated, and the Rd is converted into a gray scale voltage as an image data gray scale value, specifically:
s21, determining EL according to needs by users Target And EH Target ；
S22, judging that EL is less than or equal to EL Target Or EH ≦ EH Target If yes, entering S23; otherwise, entering S3;
s23, calculating Rd according to the following formula;
converting the Rd serving as an image data gray scale value into a gray scale voltage;
wherein R is the target gray scale value to be reduced.
Preferably, in S23, when the value of Rd is greater than the maximum value of the entire gray-scale value, the value of Rd is set as the maximum value of the range; and when the value of the Rd is smaller than the minimum value of the whole gray scale value range, the value of the Rd is taken as the minimum value of the range.
Preferably, adjusting T5 in S3, and calculating EL1, EH1, and Rd1, specifically:
s31, let T5= T2/2, then m' = m/2;
s32, calculating EL1 and EH1 according to the following formulas;
s33, calculating Rd1 according to the following formula;
in addition, in the step, when the value of the Rd1 is larger than the maximum value of the range of the whole gray scale value, the value of the Rd1 is made to be the maximum value of the range; and when the value of the Rd1 is smaller than the minimum value of the whole gray scale value range, the value of the Rd1 is taken as the minimum value of the range.
Preferably, in S4, determining whether the EL1 and the EH1 are accepted includes:
if EL 1. Ltoreq. EL Target Or EH 1. Ltoreq. EH Target If yes, the EL1 and the EH1 are judged to be accepted, otherwise, the EL1 and the EH1 are judged not to be accepted.
Preferably, adjusting T4 in S5 specifically includes:
s51, traversing all pixels of the current field, and calculating an equivalent gray-scale value R' of the current field according to the following formula;
in the above formula, rd2 is the current digital gray scale value of a certain primitive of a certain pixel in a certain field; bd is the digital gray-scale value of the previous element of the pixel corresponding to the previous field of the corresponding Rd, and T1 is the duration of each field of backlight in the field sequence; t3 is the data transmission time for completing one line; m is the current row number;
s52, calculating a difference ED between the equivalent gray-scale value and the theoretical gray-scale value according to the following formula;
ED＝|R’-R|；
in the above formula, R is the target gray scale value, and R' is the equivalent gray scale value;
s53, adjusting T4 according to ED in S52.
Preferably, in S53, T4 is adjusted according to ED in S52, specifically:
when ED =0, then T4=0, i.e. no adjustment of T4 is needed;
conversely, T4 is calculated according to the following formula:
preferably, the calculating T4 according to the formula specifically includes:
finding out the corresponding pixel when ED is maximum, and calculating EL and EH according to the following formula;
determining formula according to EL and EH size
The parameters in (1) are specifically:
when EH > EL, then Bd =0, rd = r = d; at the moment, the actual maximum error of the local field image is EH;
when EH < EL, then Bd = D, rd = R =0; the actual maximum error of the local field image is EL;
when EH = EL, the Rd1 is used as the image data gray-scale value to be converted into a gray-scale voltage.
Preferably, rd2 is calculated in S5, specifically, the calculation is performed according to the following formula:
in addition, in the step, when the value of Rd2 is larger than the maximum value of the whole gray scale value range, the value of Rd2 is made to be the maximum value of the range; and when the value of the Rd2 is smaller than the minimum value of the whole gray scale value range, the value of the Rd2 is taken as the minimum value of the range.
Compared with the prior art, the gray scale value of the current field, the backlight duration and the relative position of the backlight starting moment are adjusted according to the passively input gray scale value, so that an equivalent gray scale value is formed, and if the equivalent gray scale value is close to or equal to the target gray scale value, the smaller the error is, the less obvious or no color cast phenomenon is; through the process, the equivalent gray-scale value can be close to or equal to the target gray-scale value, so that the color cast is greatly reduced;
in addition, the translation of the backlight starting time is calculated according to the physical characteristics of the hardware platform, such as data transmission time, liquid crystal turning time, resolution ratio and the like, the backlight of the starting time is not moved, and the data transmission starting time is translated. Both of them change the relative position of the backlight starting time and the starting time of the data transmission to achieve the purpose of reducing color cast.
Drawings
FIG. 1 is a flowchart of a field sequential temporal color mixing algorithm according to an embodiment of the present invention;
FIG. 2 is a flowchart of adjusting T4 in a field sequential temporal color mixing algorithm according to an embodiment of the present invention;
fig. 3 is an image of Bd versus the gray level of the current field in a certain pixel in the field sequential temporal color mixing algorithm according to the embodiment of the present invention;
FIG. 4 is a graph of T4 versus EL and EH in a field sequential temporal blending algorithm according to an embodiment of the present invention;
FIG. 5 is a schematic diagram of the backlight illumination of the field when the m/2 th row of data transmission is completed in the field sequential temporal color mixing algorithm according to the embodiment of the present invention;
fig. 6 is a graph of the relationship between T4 and EL and EH when the m/2 th row of data is transmitted in the field sequential temporal color mixing algorithm according to the embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
In the description of the present invention, it is to be understood that the terms "vertical", "lateral", "longitudinal", "front", "rear", "left", "right", "upper", "lower", "horizontal", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description of the present invention, and do not mean that the device or member to which the present invention is directed must have a specific orientation or position, and thus, cannot be construed as limiting the present invention.
In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
The embodiment of the invention provides a field sequential time color mixing algorithm, which is implemented according to the following steps as shown in fig. 1:
s1, calculating EL and EH in a current field sequence;
s2, judging whether the EL or the EH is accepted, if so, calculating Rd, and converting the Rd serving as an image data gray level value into a gray level voltage; otherwise, entering S3;
s3, adjusting T5, and calculating EL1, EH1 and Rd1;
s4, judging whether the EL1 and the EH1 are accepted, and if so, converting the Rd1 serving as an image data gray-scale value into a gray-scale voltage; otherwise, entering S5;
s5, adjusting T4, calculating Rd2, and converting the Rd2 serving as an image data gray scale value into a gray scale voltage;
wherein EL and EH are respectively the percentage of dark part and the percentage of bright part in the area which can not be represented in the gray scale; rd is the adjusted digital gray scale value of a certain primitive in a certain pixel; t5 is translation time of the subfield backlight starting moment; EL1, EH1, and Rd1 are the percentage of dark portion, the percentage of bright portion, and the digital gray scale value of a certain element in a certain pixel in the area that cannot be represented after T5 adjustment; EL2, EH2, and Rd2 are the percentage of dark portion, the percentage of bright portion, and the digital gray scale value of a certain primitive in a certain pixel in the area that cannot be represented after T4 adjustment; t4 is the time for increasing or decreasing the backlight of the current sub-field relative to the duration of each field of backlight; t5 is the subfield backlight start time shift time.
Thus, in this embodiment, the gray scale value of the current field, the backlight duration and the relative position of the backlight start time are adjusted according to the passively input gray scale value to form an equivalent gray scale value, and if the equivalent gray scale value is close to or equal to the target gray scale value, the smaller the error is, the less obvious or no color cast phenomenon occurs; through the process, the equivalent gray-scale value can be close to or equal to the target gray-scale value, so that the color cast is greatly reduced.
Since each frame includes R, G and B fields, the S1-S5 are repeated three times until the R, G and B fields of the current frame are completed.
In a specific embodiment:
in S1, EL and EH in the current field sequence are calculated, specifically, the calculation is performed by the following formula:
in the above formula, rd is the current digital gray scale value of a certain primitive of a certain pixel in a certain field; bd is the digital gray-scale value of the previous element of the pixel corresponding to the previous field of the corresponding Rd, and T1 is the duration of each field of backlight in the field sequence; t3 is the data transmission time for completing one line; t4 is the time for increasing or decreasing the backlight of the current sub-field relative to T1; d is the range of the whole gray scale value; m is the current row number.
In a specific embodiment:
and S2, judging whether the EL or the EH is accepted or not, if so, calculating Rd, and converting the Rd into gray scale voltage as an image data gray scale value, specifically:
s21, determining EL according to needs by users Target And EH Target ；
S22, judging that EL is less than or equal to EL Target Or EH ≦ EH Target If yes, entering S23; otherwise, entering S3;
s23, calculating Rd according to the following formula;
converting the Rd serving as an image data gray scale value into a gray scale voltage;
wherein R is the target gray scale value to be reduced.
In addition, in S23, when the value of Rd is greater than the maximum value of the entire gray scale value, the value of Rd is set to be the maximum value of the range; when the value of the Rd is smaller than the minimum value of the whole gray scale value range, the value of the Rd is made to be the minimum value of the range;
for example, the value of the range D of the whole gray level value is D e [0,255]; if Rd >255, let Rd =255; if Rd <0, let Rd =0.
In a specific embodiment:
in S3, adjusting T5, and calculating EL1, EH1, and Rd1, specifically:
s31, let T5= T2/2, then m' = m/2;
s32, calculating EL1 and EH1 according to the following formulas;
s33, calculating Rd1 according to the following formula;
in the above formula, T4=0 since T4 is not adjusted;
in addition, in the step, when the value of the Rd1 is larger than the maximum value of the range of the whole gray scale value, the value of the Rd1 is made to be the maximum value of the range; and when the value of the Rd1 is smaller than the minimum value of the whole gray scale value range, the value of the Rd1 is taken as the minimum value of the range.
In a specific embodiment:
in S4, determining whether the EL1 and the EH1 are accepted, specifically:
if EL 1. Ltoreq. EL Target Or EH 1. Ltoreq. EH Target If yes, the EL1 and the EH1 are judged to be accepted, otherwise, the EL1 and the EH1 are judged not to be accepted.
In a specific embodiment:
adjusting T4 in S5, and paying attention to influence the refresh rate of the effective picture; as T4 increases, EL and EH will decrease, and the effective picture refresh rate decreases; t4 decreases (may be negative), EL and EH will increase, but the effective picture refresh rate increases.
EL and EH are errors in two most extreme cases, and the actual value can be determined according to the picture content, so as to determine T4 of the field, and dynamically adjust the T1 time of each sub-field in an effective picture of one frame.
Therefore, the specific process of adjusting T4 is shown in fig. 2, and specifically includes:
s51, traversing all pixels of the current field, and calculating an equivalent gray-scale value R' of the current field according to the following formula;
in the above formula, rd2 is the current digital gray scale value of a certain primitive of a certain pixel in a certain field; bd is the digital gray-scale value of the previous element of the pixel corresponding to the previous field of the corresponding Rd, and T1 is the duration of each field of backlight in the field sequence; t3 is the data transmission time for completing one line; m is the current row number;
s52, calculating a difference ED between the equivalent gray-scale value and the theoretical gray-scale value according to the following formula;
ED＝|R’-R|；
in the above formula, R is the target gray scale value, and R' is the equivalent gray scale value;
s53, adjusting T4 according to ED in S52.
More specifically, in S53, adjusting T4 according to ED in S52 specifically includes:
when ED =0, then T4=0, i.e. no adjustment of T4 is required;
conversely, T4 is calculated according to the following formula:
more specifically, the calculating T4 according to the formula specifically includes:
finding out the corresponding pixel when ED is maximum, and calculating EL and EH according to the following formula;
determining formula according to EL and EH size
The parameters in (1) are specifically:
when EH > EL, then Bd =0, rd = r = d; at the moment, the actual maximum error of the local field image is EH;
when EH < EL, then Bd = D, rd = R =0; the actual maximum error of the local field image is EL;
when EH = EL, the Rd1 is used as the image data gray-scale value to be converted into a gray-scale voltage.
More specifically, rd2 is calculated in S5, specifically, according to the following formula:
in addition, in the step, when the value of Rd2 is larger than the maximum value of the whole gray scale value range, the value of Rd2 is made to be the maximum value of the range; and when the value of the Rd2 is smaller than the minimum value of the whole gray scale value range, the value of the Rd2 is taken as the minimum value of the range.
In the above formula, T4 is the adjusted time.
Assuming that the maximum range of D is 255, in the process of adjusting T4, if EH > EL, bd =0, r =255, rd =255, and then T4 is calculated according to the formula; if T4< T6, then after adjusting T4, R' = R can also be made while the target parameters are met; if T4> T6, some pixel equivalent gray-scale values R' cannot restore the target value R while satisfying the target parameter, and the worst deviation is EH.
If EL > EH, bd =255, R =0, rd =0, and then T4 is calculated according to the formula; at this time, T4< T6, then after adjusting T4, R' = R can be also made while the target parameters are satisfied; if T4> T6, then some pixel equivalent gray-scale values R' cannot restore the target value R when the target parameters are satisfied, and the worst deviation is EL.
T6 is the acceptable longest duration of each field of backlight in the field sequence;
the target parameters are, for example, a target resolution, a subfield refresh rate (converted to T1), a transmission time T2 (transmission time for completing one field of data), T3 (transmission time for completing one line of data), and the like.
The field sequential temporal color mixing algorithm provided by the embodiment is based on the following principle:
knowing the target color a, which is a ' after color cast, R ' = R, G ' = G, B ' = B is necessary in order for a ' = a after compensation; now consider how to make R' = R under R field, other G field, B field methods are the same.
Due to the existence of T3, in a certain pixel of a certain row, the gray-scale value Bd of the previous field has influence on the equivalent gray-scale value R' of the current field, and the influence variable is controlled by the time of T3 m. Similarly, the gray level value Rd of the current field also has an effect on the equivalent gray level value R' of the current field, and the influencing variables are controlled by the time sum Rd of T1-T3 × m (as shown in fig. 3), so as to establish a description relation:
specifically, in a certain pixel in a certain row, according to (1), the only variable is Rd, and the value range Bd = Rd = R '∈ [0,255], so that it cannot be guaranteed that R' = R is definitely caused by adjusting the value of Rd. In order to make R' characterize R as much as possible, the variable subfield illumination time T4 is increased, thus establishing the descriptive relation as follows:
specifically, in a certain pixel on a certain row, according to (2), under the condition that Bd is known, appropriate values of Rd and T4 can be always found, so that R' = R. However, once T4 is determined for this pixel, other pixels have only one variable of Rd in the (2) calculation, so that R' cannot represent the value range of R, and there is a deviation of some pixels from the target color ED after the (2) compensation.
Because ED is present, it is necessary to find out what extreme case ED is the largest, and how to reduce this value in the extreme case so that R' characterizes the range of values of R as much as possible in the entire R field.
Looking carefully at (2), at Bd =255 (passive input brightest), the target R =0 (desired darkest), necessarily requiring Rd =0, then there is
Looking carefully at (2), at Bd =0 (darkest passive input), the target R =255 (brightest desired), necessarily requiring that Rd =255 be as bright as possible
Looking carefully at (3) and (4), when m is the last line of a given resolution, there is one pixel "brightest passively input but desired darkest" and another pixel "darkest passively input but desired brightest" (Bd = Rd = 255), where EL and EH are maximized, and EL = EH.
For example, if the resolution is 1920 × 1080, the subfield refresh rate is 180hz, t1=5.56ms, t3=2us, and t4=0, then EL = EH =38.8%. I.e. at m =1080, the two most extreme cases mentioned above occur. The compensated equivalent gray scale value R' cannot represent the gray scale value of 38.8% of the bright part and the gray scale value of 38.8% of the dark part of the target R.
To decrease EL = EH, this is achieved by increasing the time of T4; when T4= ∞, EL = EH =0, however this reduces the refresh rate of the image; in resolution 1920 × 1080, if T4=1.1ms, then EL = EH =32.4%.
The relationship between T4 and EL/EH can be as shown in FIG. 4, where the longer T4, the slower the EL or EH drop, and the lower the improvement efficiency.
In both extremes, to make EL and EH more efficient, the backlight start time can be shifted as a whole such that in (1), T3 m decreases and T1-T3 m increases so that R' is closer to R. The subfield backlight start time is shifted by time T5= T2/2, when the line data transmission of the (m/2) th line is physically completed, the backlight illumination of the field is started (as in fig. 5), gd in fig. 5 is the digital gray scale value of the next field corresponding to Rd relative to the pixel next primitive, and EL and EH are lowest (as in fig. 6).
When T5= T2/2, the equivalent gray-scale value R' is physically influenced by the gray-scale value Gd passively input for the next field from 1 to m/2 lines. Physically from (m/2+1) to m rows, the equivalent gray level value R' is affected by the gray level value Bd passively input in the previous field. So equivalent gray level value R 'of one field'
It needs to be divided into two parts of calculation, namely the (1-m/2) th line and the (m/2+1-m) th line physically. According to the formula (2), the description relation is established as follows
In summary, in order to make R 'close to or equal to R, relevant variables such as Bd, rd, gd, T1, T3, T4, T5 are used, and the degree indexes EH and EL for evaluating the reduction of R' to R are minimized by the algorithm of the present embodiment, thereby obtaining an optimal imaging effect.
In the embodiment, by adjusting the gray scale value of the original data of the current field, the translation of the backlight starting time, the backlight duration and other variables, the equivalent gray scale value can be close to or equal to the target gray scale value, so that the imaging color cast is greatly reduced;
the backlight starting time translation related to the embodiment calculates the translation time according to physical characteristics such as data transmission time, liquid crystal turning time, resolution ratio and the like; also relates to the starting time of the translation data transmission, wherein the backlight is still; both of them change the relative position of the backlight starting time and the starting time of the data transmission to achieve the purpose of reducing color cast;
the present embodiment can substantially reduce or even eliminate the color cast phenomenon without reducing hardware parameters such as brightness, refresh rate, etc.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (11)
1. A field sequence time color mixing algorithm is characterized by being implemented according to the following steps:
s1, calculating EL and EH in a current field sequence;
s2, judging whether the EL or the EH is accepted, if so, calculating Rd, and converting the Rd serving as an image data gray level value into a gray level voltage; otherwise, entering S3;
s3, adjusting T5, and calculating EL1, EH1 and Rd1;
s4, judging whether the EL1 and the EH1 are accepted, and if so, converting the Rd1 serving as an image data gray-scale value into a gray-scale voltage; otherwise, entering S5;
s5, adjusting T4, calculating Rd2, and converting the Rd2 serving as an image data gray scale value into a gray scale voltage;
wherein EL and EH are respectively the percentage of dark part and the percentage of bright part in the area which cannot be represented in the gray scale; rd is the digital gray scale value of a certain primitive in a certain pixel; t5 is translation time of the subfield backlight starting moment; EL1, EH1, and Rd1 are the percentage of dark portion, the percentage of bright portion, and the digital gray scale value of a certain element in a certain pixel in the area that cannot be represented after T5 adjustment; EL2, EH2, and Rd2 are the percentage of dark portion, the percentage of bright portion, and the digital gray scale value of a certain primitive in a certain pixel in the area that cannot be represented after T4 adjustment; t4 is the time the current sub-field backlight is increased or decreased with respect to the duration of each field backlight.
2. The field sequential temporal color mixing algorithm of claim 1, wherein the S1-S5 is repeated three times until the R, G and B fields of the current frame are completed.
3. A field sequential temporal color mixing algorithm according to claim 1 or 2, wherein the EL and EH in the current field sequence are calculated in S1, specifically, by the following formula:
in the above formula, rd is the current digital gray scale value of a certain primitive of a certain pixel in a certain field; bd is the digital gray-scale value of the previous element of the pixel corresponding to the previous field of the corresponding Rd, and T1 is the duration of each field of backlight in the field sequence; t3 is the data transmission time for completing one line; t4 is the time for increasing or decreasing the backlight of the current sub-field relative to T1; d is the range of the whole gray scale value; m is the current row number.
4. The field sequential temporal color mixing algorithm according to claim 3, wherein in S2, it is determined whether the EL or EH is accepted, if so, rd is calculated, and the Rd is converted into a grayscale voltage as an image data grayscale value, specifically:
s21, determining EL according to needs by users Target And EH Target ；
S22, judging that EL is less than or equal to EL Target Or EH ≦ EH Target If yes, entering S23; otherwise, entering S3;
s23, calculating Rd according to the following formula;
converting the Rd serving as an image data gray scale value into a gray scale voltage;
wherein R is the target gray scale value to be reduced.
5. The field sequential temporal color mixing algorithm of claim 4, wherein in S23, when the value of Rd is greater than the maximum value of the range of the entire gray scale value, let the value of Rd be the maximum value of the range; and when the value of the Rd is smaller than the minimum value of the whole gray scale value range, the value of the Rd is taken as the minimum value of the range.
6. The field sequential temporal color mixing algorithm according to claim 5, wherein adjusting T5 in S3 calculates EL1, EH1, and Rd1, specifically:
s31, let T5= T2/2, then m' = m/2;
s32, calculating EL1 and EH1 according to the following formulas;
s33, calculating Rd1 according to the following formula;
in addition, in the step, when the value of the Rd1 is larger than the maximum value of the range of the whole gray scale value, the value of the Rd1 is made to be the maximum value of the range; and when the value of the Rd1 is smaller than the minimum value of the whole gray scale value range, the value of the Rd1 is taken as the minimum value of the range.
7. The field sequential temporal color mixing algorithm according to claim 6, wherein the determining in S4 whether the EL1 and the EH1 are accepted is specifically:
if EL 1. Ltoreq. EL Target Or EH 1. Ltoreq. EH Target If yes, the EL1 and the EH1 are judged to be accepted, otherwise, the EL1 and the EH1 are judged not to be accepted.
8. The field sequential temporal color mixing algorithm according to claim 1, wherein adjusting T4 in S5 specifically comprises:
s51, traversing all pixels of the current field, and calculating an equivalent gray-scale value R' of the current field according to the following formula;
in the above formula, rd2 is the current digital gray scale value of a certain primitive of a certain pixel in a certain field; bd is the digital gray-scale value of the previous element of the pixel corresponding to the previous field of the corresponding Rd, and T1 is the duration of each field of backlight in the field sequence; t3 is the data transmission time for completing one line; m is the current row number;
s52, calculating a difference ED between the equivalent gray-scale value and the theoretical gray-scale value according to the following formula;
ED＝|R’-R|；
in the above formula, R is the target gray scale value, and R' is the equivalent gray scale value;
s53, adjusting T4 according to ED in S52.
9. The field sequential temporal color mixing algorithm according to claim 8, wherein in S53, T4 is adjusted according to ED in S52, specifically:
when ED =0, then T4=0, i.e. no adjustment of T4 is needed;
conversely, T4 is calculated according to the following formula:
10. a field sequential temporal color mixing algorithm as claimed in claim 9, wherein the field sequential temporal color mixing algorithm is applied to the field sequential temporal color mixing algorithm
Calculating T4 according to a formula, specifically:
finding out the corresponding pixel when ED is maximum, and calculating EL and EH according to the following formula;
determining formula according to EL and EH size
The parameters in (1) are specifically:
when EH > EL, then Bd =0, rd = r = d; at the moment, the actual maximum error of the local field image is EH;
when EH < EL, then Bd = D, rd = R =0; the actual maximum error of the local field image is EL;
when EH = EL, the Rd1 is used as the image data gray-scale value to be converted into a gray-scale voltage.
11. The field sequential temporal color mixing algorithm according to claim 10, wherein the Rd2 is calculated in S5, specifically, according to the following formula:
in addition, in the step, when the value of Rd2 is larger than the maximum value of the whole gray scale value range, the value of Rd2 is made to be the maximum value of the range; and when the value of the Rd2 is smaller than the minimum value of the whole gray scale value range, the value of the Rd2 is taken as the minimum value of the range.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110260064.5A CN115083360B (en) | 2021-03-10 | 2021-03-10 | Field sequence time color mixing algorithm |
| PCT/CN2021/102004 WO2022188296A1 (en) | 2021-03-10 | 2021-06-24 | Field-sequential temporal color mixing algorithm |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110260064.5A CN115083360B (en) | 2021-03-10 | 2021-03-10 | Field sequence time color mixing algorithm |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115083360A CN115083360A (en) | 2022-09-20 |
| CN115083360B true CN115083360B (en) | 2023-04-07 |
Family
ID=83227353
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110260064.5A Active CN115083360B (en) | 2021-03-10 | 2021-03-10 | Field sequence time color mixing algorithm |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN115083360B (en) |
| WO (1) | WO2022188296A1 (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007093651A (en) * | 2005-09-27 | 2007-04-12 | Hitachi Displays Ltd | Liquid crystal display device |
| CN101494039A (en) * | 2009-02-27 | 2009-07-29 | 福建华映显示科技有限公司 | Apparatus and method for adjusting white balance of color sequence method display |
| CN108810507A (en) * | 2018-06-15 | 2018-11-13 | 京东方科技集团股份有限公司 | A kind of gamut conversion method and gamut converter, display device |
| CN110400545A (en) * | 2018-04-25 | 2019-11-01 | 咸阳彩虹光电科技有限公司 | A kind of picture element matrix display methods and device |
| CN111883038A (en) * | 2020-07-28 | 2020-11-03 | 惠科股份有限公司 | Method for determining gray-scale value of pixel, display panel and computer-readable storage medium |
Family Cites Families (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3766274B2 (en) * | 2000-12-21 | 2006-04-12 | 株式会社東芝 | Time-division color display device and display method |
| JP2002221702A (en) * | 2001-01-26 | 2002-08-09 | Casio Comput Co Ltd | Field sequential liquid crystal display device |
| JP3878030B2 (en) * | 2002-02-22 | 2007-02-07 | 富士通株式会社 | Image display device and image display method |
| US6784898B2 (en) * | 2002-11-07 | 2004-08-31 | Duke University | Mixed mode grayscale method for display system |
| US20080224973A1 (en) * | 2007-03-16 | 2008-09-18 | Tpo Displays Corp. | Color Sequential Backlight Liquid Crystal Displays and Related Methods |
| CN100464219C (en) * | 2007-03-28 | 2009-02-25 | 友达光电股份有限公司 | Color sequential display device with back-light time delay control and its controlling method |
| CN101414441A (en) * | 2007-10-19 | 2009-04-22 | 陈国平 | Color liquid crystal display device driven by field sequence and drive method thereof |
| TWI402813B (en) * | 2008-11-21 | 2013-07-21 | Chunghwa Picture Tubes Ltd | Color sequential display device |
| CN101923837A (en) * | 2009-12-10 | 2010-12-22 | 浙江贝力生科技有限公司 | Method and system for automatically adjusting white balance of gray scale of liquid crystal display dark field |
| CN103185975B (en) * | 2011-12-29 | 2016-02-03 | 上海天马微电子有限公司 | Liquid crystal display panel and driving method |
| CN104036733B (en) * | 2013-03-04 | 2017-04-26 | 刘鸿达 | Display control method of display apparatus |
| WO2014188533A1 (en) * | 2013-05-22 | 2014-11-27 | Ｎｅｃディスプレイソリューションズ株式会社 | Display device, display system, image output device, and method for controlling display device |
| CN105280144A (en) * | 2014-06-12 | 2016-01-27 | 宏祐图像科技(上海)有限公司 | Overdrive technology for reducing color cast effect |
| CN104134431B (en) * | 2014-07-14 | 2016-07-27 | 京东方科技集团股份有限公司 | Field sequential display device and driving method thereof |
| CN105895054A (en) * | 2016-05-17 | 2016-08-24 | 深圳天珑无线科技有限公司 | Adjustment method of output brightness, adjustment method of Gamma curve and display device |
| CN105895040B (en) * | 2016-06-03 | 2018-12-28 | 深圳市华星光电技术有限公司 | A kind of color offset compensating method |
| CN112397036B (en) * | 2019-08-14 | 2022-05-24 | 京东方科技集团股份有限公司 | Time schedule controller, liquid crystal display device and display driving method |
-
2021
- 2021-03-10 CN CN202110260064.5A patent/CN115083360B/en active Active
- 2021-06-24 WO PCT/CN2021/102004 patent/WO2022188296A1/en active Application Filing
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007093651A (en) * | 2005-09-27 | 2007-04-12 | Hitachi Displays Ltd | Liquid crystal display device |
| CN101494039A (en) * | 2009-02-27 | 2009-07-29 | 福建华映显示科技有限公司 | Apparatus and method for adjusting white balance of color sequence method display |
| CN110400545A (en) * | 2018-04-25 | 2019-11-01 | 咸阳彩虹光电科技有限公司 | A kind of picture element matrix display methods and device |
| CN108810507A (en) * | 2018-06-15 | 2018-11-13 | 京东方科技集团股份有限公司 | A kind of gamut conversion method and gamut converter, display device |
| CN111883038A (en) * | 2020-07-28 | 2020-11-03 | 惠科股份有限公司 | Method for determining gray-scale value of pixel, display panel and computer-readable storage medium |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115083360A (en) | 2022-09-20 |
| WO2022188296A1 (en) | 2022-09-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112767867B (en) | Display panel and brightness compensation method and device thereof | |
| US8237688B2 (en) | Contrast control apparatus and contrast control method and image display | |
| US11763754B2 (en) | Grayscale data compensation method and apparatus and driver chip | |
| US8063863B2 (en) | Picture display apparatus and method | |
| US11114046B2 (en) | Display device and method for driving the same, driving apparatus, and computer-readable medium | |
| US9007295B2 (en) | Dynamic contrast ratio processing method and apparatus of liquid crystal displaying apparatus | |
| US8044978B2 (en) | Image display apparatus and high quality image providing method thereof | |
| US20230222950A1 (en) | Gamma correction method for display panel, gamma correction apparatus, and display apparatus | |
| CN107610669A (en) | Image gray-scale level luminance compensation method and device | |
| CN108962126A (en) | Display panel driving method and system and display device comprising same | |
| JP4756176B2 (en) | Liquid crystal display driving apparatus and method | |
| US7924254B2 (en) | Backlight processing system and method thereof | |
| KR100691553B1 (en) | Video signal processing circuit and television receiver | |
| US7576711B2 (en) | Contrast compensating apparatus for PDP module and method thereof | |
| US8305396B2 (en) | Method and apparatus for correcting color of display device | |
| CN115083360B (en) | Field sequence time color mixing algorithm | |
| JP3698710B1 (en) | Gradation improvement circuit and display system | |
| US20040109091A1 (en) | Apparatus and method for adaptive brightness control | |
| CN112565645A (en) | Visual angle image compensation method and circuit system | |
| US7729022B2 (en) | Method for processing image | |
| US20110242139A1 (en) | Display driver | |
| KR102666134B1 (en) | Display device | |
| US8587728B2 (en) | System and method for using partial interpolation to undertake 3D gamma adjustment of microdisplay having dynamic iris control | |
| TWI694434B (en) | Adjustment method of display apparatus with dual cells | |
| CN118135972A (en) | Data voltage compensation method, data voltage compensation device and display device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |