CN115499633A - Color correction method and system based on Mini3DLUT - Google Patents
Color correction method and system based on Mini3DLUT Download PDFInfo
- Publication number
- CN115499633A CN115499633A CN202211155785.0A CN202211155785A CN115499633A CN 115499633 A CN115499633 A CN 115499633A CN 202211155785 A CN202211155785 A CN 202211155785A CN 115499633 A CN115499633 A CN 115499633A
- Authority
- CN
- China
- Prior art keywords
- lut
- cube
- nodes
- color
- code
- 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.)
- Granted
Links
- 238000012937 correction Methods 0.000 title claims abstract description 97
- 238000000034 method Methods 0.000 title claims abstract description 38
- 239000003086 colorant Substances 0.000 claims description 15
- 238000004364 calculation method Methods 0.000 claims description 14
- 230000009021 linear effect Effects 0.000 claims description 14
- 239000007787 solid Substances 0.000 claims description 10
- 101710139363 Mini-ribonuclease 3 Proteins 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 abstract description 18
- 230000008859 change Effects 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- 238000013507 mapping Methods 0.000 description 5
- 230000008569 process Effects 0.000 description 5
- 230000009471 action Effects 0.000 description 3
- 238000007781 pre-processing Methods 0.000 description 3
- 238000010276 construction Methods 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000004075 alteration Effects 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000009022 nonlinear effect Effects 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N9/00—Details of colour television systems
- H04N9/64—Circuits for processing colour signals
- H04N9/73—Colour balance circuits, e.g. white balance circuits or colour temperature control
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N17/00—Diagnosis, testing or measuring for television systems or their details
- H04N17/04—Diagnosis, testing or measuring for television systems or their details for receivers
Landscapes
- Engineering & Computer Science (AREA)
- Multimedia (AREA)
- Signal Processing (AREA)
- Health & Medical Sciences (AREA)
- Biomedical Technology (AREA)
- General Health & Medical Sciences (AREA)
- Facsimile Image Signal Circuits (AREA)
- Color Image Communication Systems (AREA)
- Image Processing (AREA)
Abstract
The invention provides a color correction method and a system based on Mini 3DLUT. The invention mainly simplifies the three-dimensional space representation of the 3D LUT, and can greatly reduce the time for constructing the correction table in mass production on the premise of ensuring the color correction quality through a small number of nodes of the Mini3D LUT, thereby improving the mass production efficiency and realizing the accurate color correction of each playing device.
Description
Technical Field
The invention belongs to the technical field of display, and relates to a method and a system for performing color correction by utilizing a Mini3D LUT.
Background
In the display industry, there are a wide variety of playback devices, with different playback devices having different color spaces.
In order to ensure that the display effect of the image or the film is not affected by the playing device, the manufacturer needs to map the color space between the devices. At present, 3DLUT is widely used to implement color space mapping, and its implementation principle is simple, and the problem of color variation is accurately handled in a control mode of full-three-dimensional color space. Thus 3D LUTs are suitable for accurate color correction work, which are capable of handling both simple gamma values, color range and tracking errors, and correcting advanced non-linear properties, color crosstalk, hue, saturation, brightness, etc.
The 3D LUT, which is the most accurate of the current stereo color space correction systems, accomplishes the mapping of the color space by dividing the color space into regular cubes and constructing a three-dimensional look-up table for the vertices of all the cubes. Usually, the three channels of RGB are equally divided into N nodes, so that N × N nodes can be formed, and the input between the nodes is calculated by an interpolation algorithm. Common nodes for 3D LUTs are 5 × 5 × 5,9 × 9 × 9, 17 × 17 × 17, 33 × 33 × 33, 65 × 65 × 65, and the like. The current process of constructing a 3D LUT takes a long time and is not suitable for mass production. Generally, for the same batch of playing devices, manufacturers use one or more devices to be calibrated before mass production to obtain a common 3DLUT. The method completes the construction of the 3D LUT before mass production, and the 3D LUT is only required to be stored in the same batch of equipment chips without constructing a dedicated correction table for each playing equipment during mass production, thereby greatly saving mass production time and improving mass production efficiency. But this is only applicable to the case where the same batch of playback devices have the same or similar color space. If there is a large difference in the color space of the same batch of playback devices, this approach cannot achieve accurate color correction.
In order to ensure the quality of color correction, manufacturers need to construct a dedicated 3D LUT for each playing device in the mass production process for the playing devices of the same batch with larger color difference, and the construction process is time-consuming, resulting in extremely low mass production efficiency.
Disclosure of Invention
The invention provides a color correction method based on Mini3DLUT, which comprises the following steps:
selecting the number of nodes N multiplied by N required by a 3D LUT, wherein N is the number of equally dividing three channels of RGB;
simplifying the nodes of the three-dimensional color space, and reducing the number of the simplified nodes to M;
thirdly, adding nodes of the cube where the interested color is located, wherein the number of the added nodes is K;
performing color correction on the M + K nodes, and constructing a correction output table, namely a Mini3D LUT;
and step five, selecting and storing a corresponding correction table, and finishing correction output on the input color by a chip algorithm.
Further, the RGB three channels N are equally divided, thereby being capable of dividing (N-1) x (N-1) regular cubes, and only at least 1 node in each color channel direction is reserved in each cube for simplification.
Furthermore, only 1 node of each cube in each color channel direction is reserved in each cube, and the connection lines of three nodes in three color channel directions form an equilateral triangle or a right-angled triangle.
Furthermore, only four nodes are reserved in each cube, the four nodes are connected to form a triangular pyramid, and four faces of the triangular pyramid are three right-angled triangles plus one equilateral triangle, or four right-angled triangles, or four equilateral triangles.
Further, the input color is (R, G, B), and the position index of the cube is defined as follows: index is the code number of the cube, (0,0,0) is located in the cube with index =0, the code number of any cube adjacent to the code number 0 is index =1, the code numbers of the cubes are increased one by one in the long side direction of the cuboid composed of the code numbers 0 and 1, after the code number is increased to N-2, the cube adjacent to the code number 0 and not 1 is marked with the code number N-1, the code numbers of the cubes are increased one by one in the increasing direction of 0-N-2, after all the marked code numbers of the cubes in the short side direction of the cuboid are ended, the cube adjacent to the code number 0 and not 1 is marked with the code number N-1 x (N-1), and the code numbers of the cubes are increased one by one in the marking mode of 0-1 x (N-1) -1 until the cubes are marked to (N-1) x (N-1) -1.
Further, preprocessing input colors (R, G, B), obtaining a cube index through calculation, obtaining the position of the cube according to the index, obtaining correction output at a reserved node by using a Mini3D LUT according to a geometric relation formed by connecting lines of nodes reserved in the cube, and obtaining correction output 3D_LUT' at eight nodes of the cube through linear calculation of a relation expandJ fuc between corrected points and uncorrected points.
Further, the Mini3D LUT is used for calculating correction output at all uncorrected points through linear calculation expand _ fuc of the solid geometry, all node correction table 3D LUT 'is reconstructed, and the Mini3D LUT is expanded into a 3D LUT' through the linear calculation of the solid geometry
3D_LUT′＝expand_fuc(Mini_3D_LUT)。
Further, when N =5, the cube position is obtained by calculation for the input color (R, G, B) by increasing the code number in the R direction, then increasing the code number in the G direction, and finally increasing the code number in the B direction
Further, in the fifth step, a Mini3D LUT output table is selected and stored, when the playing device works, the chip algorithm calculates the output value of the uncorrected node in real time, and then the correction output is completed through interpolation operation.
Further, in the fifth step, a 3D LUT' output table is selected and saved, when the playback device is operating, the chip calculates an index of the cube where the chip is located according to the input color, and outputs a 3d _lut ″ according to the correction of the cube at the index, and the correction output is completed through interpolation operation.
The invention also provides a color correction system based on the Mini3DLUT, which comprises a node simplifying unit, a correction table output unit and a chip correction algorithm unit,
the node simplifying unit is used for simplifying the three-dimensional image according to the NxNxN nodes adopted by the 3D LUT, and ensures that at least 3 nodes are arranged in each color cube on the change of three channels; for some situations that colors are not good in performance, nodes of cubes where the colors are located need to be increased;
the correction output unit is used for carrying out color correction on the simplified nodes, constructing a Mini3D LUT and outputting the Mini3D LUT or an expanded 3D LUT' according to user selection;
and the chip correction algorithm unit calculates a correction output 3D _LUTcorresponding to the cubic node according to the input color and the stored Mini3D LUT or 3D LUT', calculates an output color by interpolation operation, and finishes color correction.
The invention has the technical effects of simplifying the three-dimensional space representation of the 3D LUT, and greatly reducing the time for constructing the correction table in mass production on the premise of ensuring the color correction quality through a small number of nodes of the Mini3D LUT, thereby improving the mass production efficiency and realizing the accurate color correction of each playing device.
Drawings
FIG. 1 is a flow chart of the method of the present invention;
FIG. 2 is a simplified node element according to embodiment 4 of the present invention;
FIG. 3 is a simplified node element according to embodiment 5 of the present invention;
FIG. 4 is a simplified node element according to embodiment 6 of the present invention;
FIG. 5 is a simplified node element according to embodiment 7 of the present invention;
FIG. 6 shows an example of cube codes of example 9 of the present invention;
FIG. 7 shows a basic cell in which colors are input according to embodiment 9 of the present invention;
fig. 8 shows a system of a Mini3D LUT according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1-3, the present invention provides a color correction method based on Mini 3DLUT.
Example 1
Firstly, selecting the number of nodes N multiplied by N required by a 3D LUT according to the color space characteristics of playing equipment and customer standards, wherein N is the number of equally dividing three channels of RGB;
simplifying the node number N used by the 3D LUT, using the simplified node to represent the whole color space, and reducing the simplified node number to M;
if the requirement on certain colors is higher or the color change amplitude in certain color spaces is large, increasing the number of nodes of the corresponding cube, wherein the number of the increased nodes is K;
only M + K nodes need to be subjected to color correction during mass production, and a Mini3D LUT is constructed;
the playing device corrects the input color in real time through a chip, and the chip correction algorithms include two types:
the method comprises the following steps: the method comprises the steps that a Mini3D LUT is stored in a chip of playing equipment, when the playing equipment works, a chip algorithm of the playing equipment obtains a cube to which the playing equipment belongs through calculation on input colors, correction output of uncorrected nodes in the cube is calculated through linear operation of the Mini3D LUT and solid geometry, and finally color output is calculated through interpolation operation to achieve color correction;
the second method comprises the following steps: in the preprocessing, a Mini3D LUT is expanded into a 3D LUT ' through linear calculation of solid geometry, the 3D LUT ' is similar to an original 3D LUT, then the 3D LUT ' is stored in a playing device chip, when the playing device works, a chip algorithm of the playing device calculates input colors to judge which cube the input colors are in, the correction output of the cube nodes is obtained, the output of the input colors is calculated through interpolation operation, and color correction is achieved.
Example 2
The number of nodes required for the 3D LUT is selected N × N.
And selecting the appropriate 3D LUT node number N multiplied by N according to the characteristics of the color space of the playing device. If the color space of the playing device has a great change in color, a larger number of nodes needs to be set, and vice versa; if the standard required by the client is high and the color mapping is strictly required, a larger number of nodes needs to be set, and vice versa. The more the number of nodes, the more accurate the color space mapping, the better the correction effect, but the longer the correction process takes, the lower the mass production efficiency. Therefore, the color characteristics of the playing device and the customer requirements need to be comprehensively considered, and the appropriate number of nodes needs to be selected.
Example 3
The nodes of the stereoscopic color space are simplified.
The RGB three channels are equally divided into N nodes, thereby obtaining a regular cube divided into (N-1) × (N-1) × (N-1). If the correction output at least 1 node in the direction of each color channel in the three color channels in the cube is reserved, the color correction information of the space can be accurately represented, the number of the nodes in the simplified stereoscopic color space is recorded as M, because the color correction is carried out in the linear domain of the color, the color output is close to the linear output, the correction output at the M simplified nodes can be utilized, the correction output of other uncorrected nodes can be obtained through the linear calculation of the solid geometry, and therefore, a 3D LUT 'can be reconstructed by utilizing a Mini3D LUT, the 3D LUT' is similar to the original 3D LUT, and the color correction effect is close to the 3D LUT.
There are many methods for node simplification, and the present invention lists several methods for node simplification, taking N =5 as an example.
Example 4
Referring to fig. 2, a 2 × 2 × 2 cube is used as a basic unit, and each face of the 2 × 2 × 2 cube retains one correction node, so that only three nodes are present in each cube in the basic unit, and the number of nodes can be greatly reduced. By the simplified node method of this embodiment, the number of 125 nodes when 3D LUT n =5 can be reduced to 36, and the Mini3D LUT is 28.8% of the number of 3D LUT nodes.
Example 5
Referring to fig. 3, a 2 × 2 × 2 cube is used as a basic unit, and the method for simplifying nodes as shown in the figure can realize that only three nodes exist in each cube in the basic unit, thereby greatly reducing the number of nodes. By the simplified node method, the number of 125 nodes when the 3D LUT n =5 can be reduced to 44, and the Mini3D LUT is 35.2% of the number of the 3D LUT nodes.
Example 6
Referring to fig. 4, a 2 × 2 × 2 cube is used as a basic unit, and the method for simplifying nodes as shown in the figure can realize that only three nodes exist in each cube in the basic unit, thereby greatly reducing the number of nodes. By the simplified node method, the number of 125 nodes when the 3D LUT n =5 can be reduced to 38, and the Mini3D LUT is 30.4% of the number of the 3D LUT nodes.
Example 7
Referring to fig. 5, a 2 × 2 × 2 cube is used as a basic unit, and the method for simplifying nodes as shown in the figure can realize that only four nodes exist in each cube, so that the number of nodes can be greatly reduced. By the simplified node method, the number of 125 nodes when the 3D LUT n =5 can be reduced to 44, and the Mini3D LUT is 35.2% of the number of the 3D LUT nodes.
Example 8
The nodes of the cube where certain colors are located are added.
The corrected output table after reducing the nodes can accurately complete the color mapping. If the customer has additional stringent requirements for certain important colors, the correction output at the nodes within the cube where these colors are located can be increased, such as grayscale, red, blue, green, etc.; if a color space has a large color change, the correction output of the cube nodes in the space can be increased, and the number of the increased nodes is recorded as K.
Example 9
And selecting and storing the Mini3D LUT, calculating the output value of the uncorrected node in real time by a chip algorithm, and finishing correction output by interpolation operation.
(1) The Mini3D LUT is stored in a chip of the playback device, and when the playback device is in operation, the chip needs to correct the input color. Taking N =5, inputting (R, G, B), taking the simplified manner of embodiment 4 as an example, the position index of the cube is defined as follows, (0,0,0) is located in the cube with index =0, the index is increased according to the R direction, then the index is increased according to the G direction, and finally the index is increased according to the B direction, referring to fig. 6, the position of the cube is obtained by calculating the input color (R, G, B)
(2) And obtaining the position of the cube according to the index, obtaining the correction output at the reserved node by using a Mini3D LUT according to the geometric relationship formed by the connecting lines of the nodes reserved in the cube, and obtaining the correction output 3D_LUT' at eight nodes of the cube by linearly calculating the relationship expand _ fuc between the corrected points and the uncorrected points through the solid geometry.
As can be seen from FIG. 7, mini _3d _lut (R4, G4, B4), mini _3d _lut (R10, G10, B10), mini _3d _lut (R12, G12, B12), mini _3d _lut (R14, G14, B14), mini _3d _lut (R16, G16, B16), mini _3d _lut (R22, G22, B22) are retained and have been corrected, and all node correction outputs of this basic unit can be obtained by the linear relationship of the solid geometry:
3d_lut′(R4,G4,B4)＝mini_3d_lut(R4,G4,B4)
3d_lut′(R10,G10,B10)＝mini_3d_lut(R10,G10,B10)
3d_lut′(R12,G12,B12)＝mini_3d_lut(R12,G12,B12)
3d_lut′(R14,G14,B14)＝mini_3d_lut(R14,G14,B14)
3d_lut′(R16,G16,B16)＝mini_3d_lut(R16,G16,B16)
3d_lut′(R22,G22,B22)＝mini_3d_lut(R22,G22,B22)
3d_lut′(R13,G13,B13)
＝(3d_lut′(R14,G14,B14)+3d_lut′(R12,G12,B12))/2
3d_lut′(R1,G1,B1)
＝3d_lut′(R10,G10,B10)+3d_lut′(R4,G4,B4)-3d_lut′(R13,G13,B13)
3d_lut′(R3,G3,B3)
＝3d_lut′(R12,G12,B12)+3d_lut′(R4,G4,B4)-3d_lut′(R13,G13,B13)
3d_lut′(R9,G9,B9)
＝3d_lut′(R12,G12,B12)+3d_lut′(R10,G10,B10)-3d_lut′(R13,G13,B13)
3d_lut′(R15,G15,B15)
＝3d_lut′(R12,G12,B12)+3d_lut′(R16,G16,B16)-3d_lut′(R13,G13,B13)
3d_lut′(R21,G21,B21)
＝3d_lut′(R12,G12,B12)+3d_lut′(R22,G22,B22)-3d_lut′(R13,G13,B13)
3d_lut′(R7,G7,B7)
＝3d_lut′(R4,G4,B4)+3d_lut′(R16,G16,B16)-3d_lut′(R13,G13,B13)
3d_lut′(R25,G25,B25)
＝3d_lut′(R22,G22,B22)+3d_lut′(R16,G16,B16)-3d_lut′(R13,G13,B13)
3d_lut′(R19,G19,B19)
＝3d_lut′(R22,G22,B22)+3d_lut′(R10,G10,B10)-3d_lut′(R13,G13,B13)
3d_lut′(R23,G23,B23)
＝3d_lut′(R22,G22,B22)+3d_lut′(R14,G14,B14)-3d_lut′(R13,G13,B13)
3d_lut′(R11,G11,B11)
＝3d_lut′(R10,G10,B10)+3d_lut′(R14,G14,B14)-3d_lut′(R13,G13,B13)
3d_lut′(R5,G5,B5)
＝3d_lut′(R4,G4,B4)+3d_lut′(R14,G14,B14)-3d_lut′(R13,G13,B13)
3d_lut′(R17,G17,B17)
＝3d_lut′(R16,G16,B16)+3d_lut′(R14,G14,B14)-3d_lut′(R13,G13,B13)
3d_lut′(R0,G0,B0)
＝3d_lut′(R3,G3,B3)+3d_lut′(R9,G9,B9)-3d_lut′(R12,G12,B12)
3d_lut′(R2,G2,B2)
＝3d_lut′(R5,G5,B5)+3d_lut′(R11,G11,B11)-3d_lut′(R14,G14,B14)
3d_lut′(R6,G6,B6)
＝3d_lut′(R3,G3,B3)+3d_lut′(R15,G15,B15)-3d_lut′(R12,G12,B12)
3d_lut′(R8,G8,B8)
＝3d_lut′(R5,G5,B5)+3d_lut′(R17,G17,B17)-3d_lut′(R14,G14,B14)
3d_lut′(R18,G18,B18)
＝3d_lut′(R9,G9,B9)+3d_lut′(R21,G21,B21)-3d_lut′(R12,G12,B12)
3d_lut′(R20,G20,B20)
＝3d_lut′(R23,G23,B23)+3d_lut′(R11,G11,B11)-3d_lut′(R14,G14,B14)
3d_lut′(R24,G24,B24)
＝3d_lut′(R21,G21,B21)+3d_lut′(R15,G15,B15)-3d_lut′(R12,G12,B12)
3d_lut′(R26,G26,B26)
＝3d_lut′(R23,G23,B23)+3d_lut′(R17,G17,B17)-3d_lut′(R14,G14,B14)
the solid geometry calculation only refers to one basic unit, is not limited to the method, and can be performed by using the basic unit together with the correction output of the adjacent basic unit.
(3) From the corrected output at the eight nodes of this cube (denoted as 3d _lut "), the color output is calculated by the interpolation operation used (denoted as inter _ func). At present, there are many mature interpolation algorithms, such as three-dimensional linear interpolation algorithm
(R out ,G out ,B out )＝inter_func(R,G,B,3D_LUT″)。
Example 10
And (4) selecting and saving the 3D LUT', and finishing correction output by a chip algorithm through interpolation operation.
Saving the 3D LUT' in the chip of the playback device, needs to complete:
(1) In the preprocessing, the Mini3D LUT is expanded into a 3D LUT' by linear calculation of solid geometry, and the calculation method is the same as that of embodiment 9, but is not limited thereto
3D_LUT′＝expand_fuc(Mini_3D_LUT)
(2) Storing the 3D LUT' in a playing device chip;
(3) When the player works, the chip needs to calculate the index of the cube it is in through the input color (same as embodiment 9)
(4) With the corrected output at this cube node, 3D _LUT ", the color output is calculated by the interpolation operation used (denoted inter _ func). At present, there are many mature interpolation algorithms, such as three-dimensional linear interpolation algorithm
(R out ,G out ,B out )＝inter_func(R,G,B,3D_LUT″)
By comparing example 9 with example 10, it is found that the correction table required to be saved in example 9 is small, but the chip algorithm requires much processing to be completed; while the embodiment 10 needs to store a large correction table, the chip algorithm needs to perform less processing.
Example 11
A system for implementing the Mini3D LUT as shown in fig. 8 includes a node simplification unit, a correction table output unit, and a chip correction algorithm unit.
The node simplifying unit is used for simplifying the three-dimensional image according to the NxNxN nodes adopted by the 3D LUT, and ensures that at least 3 nodes are arranged in each color cube on the change of three channels; for some colors to perform poorly, the nodes of the cube where the colors are located need to be increased.
And the correction output unit is used for carrying out color correction on the simplified nodes, constructing a Mini3D LUT and outputting the Mini3D LUT or an expanded 3D LUT' according to user selection.
And the chip correction algorithm unit calculates a correction output 3D _LUTcorresponding to the cubic node according to the input color and the stored Mini3D LUT or 3D LUT', calculates an output color by interpolation operation, and finishes color correction.
The main innovation point of the invention is that the three-dimensional space representation of the 3D LUT is simplified, and the time for constructing the correction table in mass production can be greatly reduced through a small number of nodes of the Mini3D LUT on the premise of ensuring the color correction quality, so that the mass production efficiency is improved, and the accurate color correction is realized for each playing device.
On the premise of ensuring the color correction effect, the time for constructing the 3D LUT in mass production is reduced and the mass production efficiency is improved by reducing the number of nodes in the color space. Since color correction is usually performed in a linear color space, and the correction tables are close to linearity, especially the correction outputs at close nodes, we can delete some nodes and represent the whole 3D LUT by a simplified correction output table Mini3D LUT.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (10)
1. A color correction method based on Mini3DLUT is characterized by comprising the following steps:
selecting the number of nodes N multiplied by N required by a 3D LUT, wherein N is the number of equally dividing three channels of RGB;
simplifying the nodes of the three-dimensional color space, and reducing the number of the simplified nodes to M;
thirdly, adding nodes of the cube where the interested color is located, wherein the number of the added nodes is K;
performing color correction on the M + K nodes, and constructing a correction output table, namely Mini 3DLUT;
and step five, selecting and storing a corresponding correction table, and finishing correction output on the input color by a chip algorithm.
2. The Mini3 DLUT-based color correction method of claim 1, wherein the three RGB channels are divided into N equal parts, so that (N-1) x (N-1) regular cubes can be divided, and each cube is simplified by only retaining at least 1 node in each color channel direction.
3. The color correction method based on Mini3DLUT of claim 2, wherein only 1 node in each color channel direction is reserved in each cube, and the connection lines of three nodes in three color channel directions form an equilateral triangle or a right triangle.
4. The color correction method according to claim 2, wherein only four nodes are reserved in each cube, the four nodes are connected to form a triangular pyramid, and four faces of the triangular pyramid are either three right-angled triangles plus one equilateral triangle, four right-angled triangles, or four equilateral triangles.
5. The color correction method based on Mini3DLUT of claim 2, wherein the input color is (R, G, B), and the position index of the cube is defined as follows: the index is the code of a cube, the code of the cube in which (0,0,0) is located is index =0, the code of any cube adjacent to the code 0 is index =1, the codes of the cubes are increased one by one in the long side direction of the cuboid composed of the codes 0 and 1, after the codes are increased to N-2, the cube adjacent to the code 0 and not adjacent to the code 1 is continuously marked with the code N-1, the codes of the cubes are increased one by one in the increasing direction of 0-N-2, after all the codes of the cubes in the short side direction of the cuboid are marked, the cube adjacent to the code 0 and not adjacent to the code 1 and not adjacent to the code N-1 is continuously marked with the code (N-1) x (N-1), and the codes of the cubes are increased one by one in the marking mode of 0 to (N-1) x (N-1) -1 until the cubes are marked to (N-1) x (N-1) -1.
6. The color correction method based on Mini3DLUT of claim 5, wherein the input colors (R, G, B) are preprocessed, cube index is obtained by calculation, the position of the cube is obtained according to the index, then the correction output at the reserved node is obtained by utilizing Mini3D LUT according to the geometric relationship formed by the connecting lines of the nodes reserved in the cube, and the correction output 3D_LUT' at eight nodes of the cube is obtained by linearly calculating the relationship expand _ fuc between the corrected point and the uncorrected point according to the solid geometry between the corrected point and the uncorrected point.
7. The color correction method based on Mini3DLUT of claim 6, wherein the Mini3D LUT is used to calculate the correction output at all uncorrected points by stereo geometry linear calculation expand _ fuc, reconstruct all node correction table 3D LUT ', and expand the Mini3D LUT into 3D LUT' expressed as
3D_LUT′＝expand_fuc(Mini_3D_LUT)。
8. The color correction method of claim 7, wherein when N =5, the code is increased in the R direction, then in the G direction, and finally in the B direction, and the cube position is obtained by calculation for the input color (R, G, B)
9. The color correction method based on Mini3DLUT of claim 6, wherein in the fifth step, a Mini3D LUT output table is selected and stored, when the playing device works, the output value of the uncorrected node is calculated in real time by a chip algorithm, and then the correction output is completed by interpolation operation.
10. The color correction method based on Mini3DLUT of claim 7, wherein in the fifth step, the output table of 3D LUT' is selected and saved, when the playback device is in operation, the chip calculates the index of the cube where the chip is located by the input color, and completes the correction output by interpolation operation according to the correction output of the cube at the index, namely, 3D _LUT ".
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211155785.0A CN115499633B (en) | 2022-09-23 | 2022-09-23 | Color correction method and system based on Mini 3DLUT |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211155785.0A CN115499633B (en) | 2022-09-23 | 2022-09-23 | Color correction method and system based on Mini 3DLUT |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115499633A true CN115499633A (en) | 2022-12-20 |
| CN115499633B CN115499633B (en) | 2024-05-28 |
Family
ID=84469544
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211155785.0A Active CN115499633B (en) | 2022-09-23 | 2022-09-23 | Color correction method and system based on Mini 3DLUT |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115499633B (en) |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005072850A (en) * | 2003-08-22 | 2005-03-17 | Noritsu Koki Co Ltd | Adjusting method of three dimensional lut and color conversion system equipped with three dimensional lut |
| JP2006019899A (en) * | 2004-06-30 | 2006-01-19 | Seiko Epson Corp | Color converting apparatus and color converting method |
| JP2007251709A (en) * | 2006-03-17 | 2007-09-27 | Fujitsu Ltd | Color correction method, color correction apparatus, and color correction program |
| US20090161183A1 (en) * | 2007-12-20 | 2009-06-25 | Xerox Corporation | Optimal node placement for multi-dimensional profile luts for arbitrary media and halftones using parameterized minimization |
| US20090161126A1 (en) * | 2007-12-20 | 2009-06-25 | Xerox Corporation | Method for upsampling color correction tables, an apparatus for creating an upsampled color corretion table, and a program for upsampling color correction tables |
| US20110222080A1 (en) * | 2010-03-15 | 2011-09-15 | Vishal Monga | Methods, systems and apparatus for jointly optimizing node locations and corresponding output values of a color look-up-table (lut) |
| CN111770320A (en) * | 2020-07-14 | 2020-10-13 | 深圳市洲明科技股份有限公司 | Color correction method and device, color correction equipment and storage medium |
| CN112017105A (en) * | 2020-08-13 | 2020-12-01 | 深圳市洲明科技股份有限公司 | Color correction FPGA implementation device and method, color correction device and storage medium |
| WO2022040889A1 (en) * | 2020-08-24 | 2022-03-03 | 华为技术有限公司 | Display method and apparatus, and electronic device |
-
2022
- 2022-09-23 CN CN202211155785.0A patent/CN115499633B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005072850A (en) * | 2003-08-22 | 2005-03-17 | Noritsu Koki Co Ltd | Adjusting method of three dimensional lut and color conversion system equipped with three dimensional lut |
| JP2006019899A (en) * | 2004-06-30 | 2006-01-19 | Seiko Epson Corp | Color converting apparatus and color converting method |
| JP2007251709A (en) * | 2006-03-17 | 2007-09-27 | Fujitsu Ltd | Color correction method, color correction apparatus, and color correction program |
| US20090161183A1 (en) * | 2007-12-20 | 2009-06-25 | Xerox Corporation | Optimal node placement for multi-dimensional profile luts for arbitrary media and halftones using parameterized minimization |
| US20090161126A1 (en) * | 2007-12-20 | 2009-06-25 | Xerox Corporation | Method for upsampling color correction tables, an apparatus for creating an upsampled color corretion table, and a program for upsampling color correction tables |
| US20110222080A1 (en) * | 2010-03-15 | 2011-09-15 | Vishal Monga | Methods, systems and apparatus for jointly optimizing node locations and corresponding output values of a color look-up-table (lut) |
| CN111770320A (en) * | 2020-07-14 | 2020-10-13 | 深圳市洲明科技股份有限公司 | Color correction method and device, color correction equipment and storage medium |
| WO2022012330A1 (en) * | 2020-07-14 | 2022-01-20 | 深圳市洲明科技股份有限公司 | Color correction method and apparatus, color correction device, and storage medium |
| CN112017105A (en) * | 2020-08-13 | 2020-12-01 | 深圳市洲明科技股份有限公司 | Color correction FPGA implementation device and method, color correction device and storage medium |
| WO2022040889A1 (en) * | 2020-08-24 | 2022-03-03 | 华为技术有限公司 | Display method and apparatus, and electronic device |
Non-Patent Citations (2)
| Title |
|---|
| 王京生: "色彩管理在4K影视制作中的应用", 《现代电视技术》, 15 June 2016 (2016-06-15), pages 108 - 112 * |
| 贾庆轩;徐卉;宋荆洲;高欣;孙汉旭;: "基于投影仪-相机系统的多投影颜色校正技术", 系统仿真学报, no. 05, 8 May 2013 (2013-05-08) * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115499633B (en) | 2024-05-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5327509A (en) | Compressed image system for texture patterns | |
| CN111770320B (en) | Color correction method and device, color correction equipment and storage medium | |
| KR20040011760A (en) | Method for color correction | |
| KR20100027169A (en) | Method of creating a gamut boundary descriptor preserving the discontinuities of an actual gamut surface | |
| KR101518357B1 (en) | Method and system for predictive scaling of colour mapped images | |
| JP4016234B2 (en) | Image processing method and image processing apparatus | |
| CN115499633B (en) | Color correction method and system based on Mini 3DLUT | |
| WO2003101084A1 (en) | Color conversion method and color conversion device | |
| JP3171081B2 (en) | Image processing device | |
| JP2002152534A (en) | Method and apparatus for converting three-dimensional signal | |
| EP0923048B1 (en) | Apparatus for tetrahedral and pruned tetrahedral interpolation | |
| EP0923049B1 (en) | Apparatus for tetrahedral and pruned tetrahedral interpolation | |
| JP3912903B2 (en) | Data conversion method and apparatus | |
| Kang | Comparisons of three-dimensional interpolation techniques by simulations | |
| Chuang | Derived equivalence in 𝑆𝐿₂ (𝑝²) | |
| US5966474A (en) | Non-symmetric radial and non-symmetric pruned radial interpolation | |
| JP2528463B2 (en) | Color separation image correction method and apparatus | |
| US6028683A (en) | Common pruned radial and pruned tetrahedral interpolation hardware implementation | |
| JP4089728B2 (en) | Multidimensional interpolator | |
| JP3611890B2 (en) | Color conversion device | |
| JPH04196676A (en) | Method of estimating color | |
| JP2521182B2 (en) | Color correction device | |
| JPH01190456A (en) | Color separation image correction apparatus | |
| JP4001938B2 (en) | Multidimensional interpolation method | |
| JP2739345B2 (en) | Color correction method |
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 | ||
| CB02 | Change of applicant information |
Address after: Room 1905, building 4, No. 209, Zhuyuan Road, high tech Zone, Suzhou City, Jiangsu Province 215000 Applicant after: Sunrise Microelectronics (Suzhou) Co.,Ltd. Address before: Room 1905, building 4, No. 209, Zhuyuan Road, high tech Zone, Suzhou City, Jiangsu Province 215000 Applicant before: Sheng Microelectronics (Suzhou) Co.,Ltd. |
|
| CB02 | Change of applicant information | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |