CN106570928A - Image-based re-lighting method - Google Patents
Image-based re-lighting method Download PDFInfo
- Publication number
- CN106570928A CN106570928A CN201610998904.7A CN201610998904A CN106570928A CN 106570928 A CN106570928 A CN 106570928A CN 201610998904 A CN201610998904 A CN 201610998904A CN 106570928 A CN106570928 A CN 106570928A
- Authority
- CN
- China
- Prior art keywords
- image
- training
- artificial neural
- neural network
- pixel
- 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
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T15/00—3D [Three Dimensional] image rendering
- G06T15/10—Geometric effects
- G06T15/20—Perspective computation
- G06T15/205—Image-based rendering
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06N—COMPUTING ARRANGEMENTS BASED ON SPECIFIC COMPUTATIONAL MODELS
- G06N3/00—Computing arrangements based on biological models
- G06N3/02—Neural networks
- G06N3/04—Architecture, e.g. interconnection topology
- G06N3/045—Combinations of networks
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06N—COMPUTING ARRANGEMENTS BASED ON SPECIFIC COMPUTATIONAL MODELS
- G06N3/00—Computing arrangements based on biological models
- G06N3/02—Neural networks
- G06N3/08—Learning methods
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Computing Systems (AREA)
- General Health & Medical Sciences (AREA)
- Artificial Intelligence (AREA)
- Computational Linguistics (AREA)
- Data Mining & Analysis (AREA)
- Evolutionary Computation (AREA)
- Biomedical Technology (AREA)
- Molecular Biology (AREA)
- Biophysics (AREA)
- General Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Mathematical Physics (AREA)
- Software Systems (AREA)
- Health & Medical Sciences (AREA)
- Geometry (AREA)
- Computer Graphics (AREA)
- Image Analysis (AREA)
Abstract
The present invention discloses an image-based re-lighting method and belongs to the computer graphics field. In order to achieve re-lighting as accurately as possible with as few samples as possible, quantitative random sampling is performed repeatedly in the spaces of image samples and image pixels, and training is performed through using an artificial neural network until the training accuracy of all pixels reaches a set threshold value; and provided that the artificial neural network has a requirement for minimum samples in training, the Bagging algorithm of ensemble learning is utilized to perform averaging processing on pixel training samples when the pixel training samples are insufficient. The method of the present invention is tested in a simulated three-dimensional scene, and a test result indicates that the image-based re-lighting method has the advantages of less training time and high robustness as well as fewer image samples, high speed, excellent real-time performance and high PSNR (peak signal to noise ratio) of a reconstructed scene image under the same relative error accuracy compared with the prior art.
Description
Technical field
The present invention relates to a kind of heavy illumination method based on image, belongs to machine learning and graphics field.
Background technology
Illumination again (Image-based Relighting, IBR) based on image, also referred to as image-based rending
(Image-based Rendering), its objective is the image from capture, calculates and obtains optical transport matrix and draw out new
Light conditions under scene image.Its sharpest edges are the geological informations without the need for scene, render and do not receive scene complexity shadow
Ring, and can also show the various lighting effects such as reflection, refraction, scattering.Therefore, IBR has become at once graphics since the proposition
Field focus of attention.
IBR generally requires to obtain image pattern by intensive sampling, considerably increases working strength and memory space.Can
Using machine learning method, by the sampling of small sample, accurately realize based on the illumination again of image as far as possible, be urgent need to resolve
Problem.
The content of the invention
The technical problem to be solved is to provide a kind of heavy illumination method based on image.By image pattern by
It is cumulative plus, pixel space stochastical sampling, three-layer neural network be trained and Bagging integrated study thoughts comprehensive fortune
With it is achieved thereby that small sample, high-precision heavy lighting effect.
The present invention is employed the following technical solutions to solve above-mentioned technical problem:
The present invention provides a kind of heavy illumination method based on image, it is characterised in that including step in detail below:
Step 1:Gather one group of scene data, including spot light LigX, LigY coordinate and its corresponding fixing
The image set ImageSet of viewpoint output, is calculated mean value ImgAvg_s of the image set ImageSet in tri- passages of R, G, B
R、ImgAvg_G、ImgAvg_B;
Step 2:The stochastical sampling in image set ImageSet, constitutes image subset of the image pattern number for ImageNum
ImageSubset;
Step 3:The stochastical sampling in the pixel space of image subset ImageSubset, obtains the instruction of artificial neural network
Practice sample set, specially:
(1) stochastical sampling in the pixel space of image subset ImageSubset, constitutes pixel point set, wherein, hits
For PixNum, the coordinate of pixel is [Px, Py];
(2) training sample set includes two parts of input and the output for corresponding to artificial neural network respectively, wherein, input
Part include Px, Py, LigX, LigY, ImgAvg_R, ImgAvg_G, ImgAvg_B, output par, c be [LigX, LigY] with
The image rgb value of [Px, Py] corresponding position;
Step 4:It is trained using the training sample set pair artificial neural network of step 3, after the completion of training, will be relatively flat
Square error is less than or equal to preset first threshold value δ1Pixel be labeled as the artificial neural network that the training is completed;
Step 5, in step 4 stochastical sampling again in unlabelled pixel, trains again artificial neural network, until
The pixel that training sample is concentrated all is labeled or unlabelled pixel is unsatisfactory for the most sample that artificial neural network is trained
This requirement;It is integrated using Bagging when the smallest sample that unlabelled pixel is unsatisfactory for artificial neural network training is required
The thought of study, unlabelled pixel together decides on its output by all neutral nets;
Step 6:With the artificial neural network test chart image set ImageSet for training, if measuring accuracy reaches default second
Threshold value δ2, then the artificial neural network for training, execution step 7 are preserved;Otherwise, increase image pattern number ImageNum, return
2;
Step 7:Scene under reconstructing light source at an arbitrary position with the neutral net for training.
As the further prioritization scheme of the present invention, hits PixNum >=Pix in the step 3min, wherein,TminIt is the smallest sample number of artificial neural network training need, a is coefficient and a >=1).
As the further prioritization scheme of the present invention, entered using training sample set pair artificial neural network in the step 4
Before row training, training sample set is normalized.
Used as the further prioritization scheme of the present invention, the artificial neural network structure in the step 4 is 7 input sections
Point, 2 hidden layers, 3 output nodes, wherein, the nodes of two hidden layers are identical, input node be respectively Px, Py, LigX,
LigY、ImgAvg_R、ImgAvg_G、ImgAvg_B;Output node is respectively [LigX, LigY] and [Px, Py] corresponding position image
Rgb value;The nodes N of hidden layerhideDetermined by experiment.
As the further prioritization scheme of the present invention, the smallest sample number T of artificial neural network training needmin=b [(7+
1)×Nhide+(Nhide+1)×Nhide+(Nhide+ 1) × 3], wherein, b is coefficient and b >=10.
As the further prioritization scheme of the present invention, the relative square error of pixel in step 4
Wherein,Represent the actual rgb value of the ith pixel point of jth image, Ij(Pixi) represent ANN
The rgb value of the ith pixel point of the jth image of network prediction output.
As the further prioritization scheme of the present invention, when unlabelled pixel is unsatisfactory for artificial neural network in step 5
When the smallest sample of training is required, using the thought of Bagging integrated studies, the output of unlabelled pixel is by training
The output simple average of all artificial neural networks draws.
As the further prioritization scheme of the present invention, relative mean square error in the step 6
As the further prioritization scheme of the present invention, increase image pattern number ImageNum in step 6 according to actual needs.
Used as the further prioritization scheme of the present invention, image pattern number ImageNum increases by 20.
The present invention adopts above technical scheme compared with prior art, with following technique effect:The present invention is in simulation
Tested in two three-dimensional scenics, as a result shown, compared with prior art, not only the training time is few, and robustness is strong;In phase
Under same relative error precision, image pattern again needed for illumination is less, and the PSNR values for reconstructing scene image are higher.
Description of the drawings
Fig. 1 is method of the present invention flow chart.
When Fig. 2 is the training error of the Dragon and Mitsuba scenes that the present invention and prior art is respectively adopted and training
Between comparison diagram, wherein, (a) be Dragon scenes training error, (b) be Mitsuba scenes training error, (c)
The training time of Dragon scenes, (d) be Mitsuba scenes training time.
Specific embodiment
Technical scheme is described in further detail below in conjunction with the accompanying drawings:
A kind of heavy illumination method based on image of the present invention, as shown in figure 1, including:
Step 1:Gather one group of scene data (Dagon, Mitsuba), including spot light LigX, LigY coordinate and
Its corresponding image set ImageSet in fixed view output;Image set is calculated in the mean value of tri- passages of R, G, B, is obtained
ImgAvg_R、ImgAvg_G、ImgAvg_B;Contextual data is specifically as shown in table 1.
The contextual data of table 1
Scene | Distribution of light sources | Picture size |
Dragon | 31×31 | 64×48 |
Mitsuba | 21×21 | 64×48 |
Step 2:The stochastical sampling in image set ImageSet, constitutes image subset ImageSubset, and image pattern number is
ImageNum。
Step 3:The stochastical sampling in pixel of the image subset as ImageSubset, obtaining artificial neural network needs
Training sample set;
(1) in image subset as the pixel space stochastical sampling of ImageSubset, pixel point set is constituted, hits is
PixNum, the coordinate of pixel is [Px, Py];
(2) training sample set is constituted by being input into, exporting two parts, wherein input attribute include LigX, LigY, Px, Py,
ImgAvg_R, ImgAvg_G, ImgAvg_B, output attribute is the image rgb value of [LigX, LigY] and [Px, Py] corresponding position.
Step 4:It is trained using training sample set pair artificial neural network, after the completion of training, will be with respect to square error
RSE≤predetermined threshold value δ1Pixel be labeled as the artificial neural network that the training is completed.
Step 5:In step 4 stochastical sampling again in unlabelled pixel, trains again artificial neural network, until
The pixel that training sample is concentrated all is labeled or unlabelled pixel is unsatisfactory for the most sample that artificial neural network is trained
This requirement;When the smallest sample that unmarked pixel is unsatisfactory for artificial neural network training is required, using Bagging integrated studies
Thought, by all neutral nets together decide on its output.
Step 6:With the artificial neural network test chart image set ImageSet for training, if measuring accuracy reaches default threshold
Value δ2, then the artificial neural network for training is preserved;Otherwise, increase image pattern number ImageNum, restart from step 2.
Step 7:With the scene under the artificial neural network reconstruct any light source position for training.Stochastical sampling and training
The image set ImagesetTest of Imageset equivalent amounts, with the neutral net reconstruct scene for training.
As shown in Fig. 2 with Ren et al. in " Image Based Relighting Using Neural
Networks.ACM Transactions on Graphics, 2015.34 (4) " technology in text is compared.Wherein, in Fig. 2
A () and (b) is respectively the training error figure of Dragon and Mitsuba scenes, be (c) respectively Dragon and Mitsuba fields with (d)
The training time schematic diagram of scape.By Fig. 2 it will be apparent that, it is (empty in figure using the method for the present invention with the increase of image pattern number
Shown in line), RMSE is substantially fast than what Ren method declined, and also just meaning needs less sample to reach identical precision;Same
Training time required for the method for the present invention is also below Ren methods.
Table 2 is that the test data to two scenes of Dragon and Mitsuba carries out scene reconstruction result, is shown using less
Image can obtain RMSE value lower than Ren method.
The scene reconstruction result of table 3
The above, the only specific embodiment in the present invention, but protection scope of the present invention is not limited thereto, and appoints
What be familiar with the people of the technology disclosed herein technical scope in, it will be appreciated that the conversion expected or replacement, all should cover
The present invention include within the scope of, therefore, protection scope of the present invention should be defined by the protection domain of claims.
Claims (10)
1. a kind of heavy illumination method based on image, it is characterised in that including step in detail below:
Step 1:Gather one group of scene data, including LigX, LigY coordinate of spot light and its corresponding in fixed view
The image set ImageSet of output, be calculated image set ImageSet tri- passages of R, G, B mean value ImgAvg_R,
ImgAvg_G、ImgAvg_B;
Step 2:The stochastical sampling in image set ImageSet, constitutes image subset of the image pattern number for ImageNum
ImageSubset;
Step 3:The stochastical sampling in the pixel space of image subset ImageSubset, obtains the training sample of artificial neural network
This collection, specially:
(1) stochastical sampling in the pixel space of image subset ImageSubset, constitutes pixel point set, wherein, hits is
PixNum, the coordinate of pixel is [Px, Py];
(2) training sample set includes two parts of input and the output for corresponding to artificial neural network respectively, wherein, importation
Including Px, Py, LigX, LigY, ImgAvg_R, ImgAvg_G, ImgAvg_B, output par, c is [LigX, LigY] and [Px, Py]
The image rgb value of corresponding position;
Step 4:It is trained using the training sample set pair artificial neural network of step 3, after the completion of training, will be with respect to a square mistake
Difference is less than or equal to preset first threshold value δ1Pixel be labeled as the artificial neural network that the training is completed;
Step 5, in step 4 stochastical sampling again in unlabelled pixel, trains again artificial neural network, until training
The whole labeled or unlabelled pixels of pixel in sample set are unsatisfactory for the smallest sample of artificial neural network training will
Ask;When the smallest sample that unlabelled pixel is unsatisfactory for artificial neural network training is required, using Bagging integrated studies
Thought, unlabelled pixel by all neutral nets together decide on its output;
Step 6:With the artificial neural network test chart image set ImageSet for training, if measuring accuracy reaches default Second Threshold
δ2, then the artificial neural network for training, execution step 7 are preserved;Otherwise, increase image pattern number ImageNum, return 2;
Step 7:Scene under reconstructing light source at an arbitrary position with the neutral net for training.
2. a kind of heavy illumination method based on image according to claim 1, it is characterised in that sample in the step 3
Number PixNum >=Pixmin, wherein,TminIt is the smallest sample number of artificial neural network training need, a
It is coefficient and a >=1).
3. a kind of heavy illumination method based on image according to claim 1, it is characterised in that utilize in the step 4
Before training sample set pair artificial neural network is trained, training sample set is normalized.
4. a kind of heavy illumination method based on image according to claim 1, it is characterised in that the people in the step 4
Artificial neural networks structure is 7 input nodes, 2 hidden layers, 3 output nodes, wherein, the nodes of two hidden layers are identical, defeated
Ingress is respectively Px, Py, LigX, LigY, ImgAvg_R, ImgAvg_G, ImgAvg_B;Output node is [LigX, LigY]
With the image rgb value of [Px, Py] corresponding position;The nodes N of hidden layerhideDetermined by experiment.
5. a kind of heavy illumination method based on image according to claim 1 or 2 or 4, it is characterised in that ANN
The smallest sample number T of network training needmin=b [(7+1) × Nhide+(Nhide+1)×Nhide+(Nhide+ 1) × 3], wherein, b is
Coefficient and b >=10.
6. a kind of heavy illumination method based on image according to claim 1, it is characterised in that pixel in step 4
With respect to square errorWherein,Represent the of jth image
The actual rgb value of i pixel, Ij(Pixi) represent that the jth of neural network prediction output opens the ith pixel point of image
Rgb value.
7. a kind of heavy illumination method based on image according to claim 1, it is characterised in that when unmarked in step 5
Pixel be unsatisfactory for artificial neural network training smallest sample require when, using the thought of Bagging integrated studies, do not mark
The output of the pixel of note is drawn by the output simple average of all artificial neural networks for training.
8. a kind of heavy illumination method based on image according to claim 1, it is characterised in that the phase in the step 6
To mean square error
9. a kind of heavy illumination method based on image according to claim 1, it is characterised in that according to reality in step 6
Need to increase image pattern number ImageNum.
10. a kind of heavy illumination method based on image according to claim 9, it is characterised in that image pattern number
ImageNum increases by 20.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201610998904.7A CN106570928B (en) | 2016-11-14 | 2016-11-14 | A kind of heavy illumination method based on image |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201610998904.7A CN106570928B (en) | 2016-11-14 | 2016-11-14 | A kind of heavy illumination method based on image |
Publications (2)
Publication Number | Publication Date |
---|---|
CN106570928A true CN106570928A (en) | 2017-04-19 |
CN106570928B CN106570928B (en) | 2019-06-21 |
Family
ID=58541876
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201610998904.7A Expired - Fee Related CN106570928B (en) | 2016-11-14 | 2016-11-14 | A kind of heavy illumination method based on image |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN106570928B (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107909640A (en) * | 2017-11-06 | 2018-04-13 | 清华大学 | Face weight illumination method and device based on deep learning |
CN108765540A (en) * | 2018-04-26 | 2018-11-06 | 河海大学 | A kind of heavy illumination method based on image and integrated study |
CN110033055A (en) * | 2019-04-19 | 2019-07-19 | 中共中央办公厅电子科技学院(北京电子科技学院) | A kind of complex object image weight illumination method based on the parsing of semantic and material with synthesis |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20140293010A1 (en) * | 2009-11-18 | 2014-10-02 | Quang H. Nguyen | System for executing 3d propagation for depth image-based rendering |
CN104700109A (en) * | 2015-03-24 | 2015-06-10 | 清华大学 | Method and device for decomposing hyper-spectral intrinsic images |
CN105447906A (en) * | 2015-11-12 | 2016-03-30 | 浙江大学 | Method for calculating lighting parameters and carrying out relighting rendering based on image and model |
-
2016
- 2016-11-14 CN CN201610998904.7A patent/CN106570928B/en not_active Expired - Fee Related
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20140293010A1 (en) * | 2009-11-18 | 2014-10-02 | Quang H. Nguyen | System for executing 3d propagation for depth image-based rendering |
CN104700109A (en) * | 2015-03-24 | 2015-06-10 | 清华大学 | Method and device for decomposing hyper-spectral intrinsic images |
CN105447906A (en) * | 2015-11-12 | 2016-03-30 | 浙江大学 | Method for calculating lighting parameters and carrying out relighting rendering based on image and model |
Non-Patent Citations (1)
Title |
---|
PEIRAN REN等: "Image Based Relighting Using Neural Networks", 《ACM TRANSACTIONS ON GRAPHICS》 * |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107909640A (en) * | 2017-11-06 | 2018-04-13 | 清华大学 | Face weight illumination method and device based on deep learning |
CN107909640B (en) * | 2017-11-06 | 2020-07-28 | 清华大学 | Face relighting method and device based on deep learning |
CN108765540A (en) * | 2018-04-26 | 2018-11-06 | 河海大学 | A kind of heavy illumination method based on image and integrated study |
CN108765540B (en) * | 2018-04-26 | 2022-04-12 | 河海大学 | Relighting method based on image and ensemble learning |
CN110033055A (en) * | 2019-04-19 | 2019-07-19 | 中共中央办公厅电子科技学院(北京电子科技学院) | A kind of complex object image weight illumination method based on the parsing of semantic and material with synthesis |
Also Published As
Publication number | Publication date |
---|---|
CN106570928B (en) | 2019-06-21 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN111292264B (en) | Image high dynamic range reconstruction method based on deep learning | |
Malu et al. | Learning photography aesthetics with deep cnns | |
Cao et al. | Ancient mural restoration based on a modified generative adversarial network | |
CN109961434A (en) | Non-reference picture quality appraisement method towards the decaying of level semanteme | |
CN109472193A (en) | Method for detecting human face and device | |
CN109711401A (en) | A kind of Method for text detection in natural scene image based on Faster Rcnn | |
CN108764250A (en) | A method of extracting essential image with convolutional neural networks | |
DE102021105249A1 (en) | MICROTRAINING FOR ITERATIVE REFINEMENT OF A NEURAL NETWORK WITH FEW ADAPTATIONS | |
CN110992366A (en) | Image semantic segmentation method and device and storage medium | |
CN110532914A (en) | Building analyte detection method based on fine-feature study | |
CN106570928A (en) | Image-based re-lighting method | |
CN111161278A (en) | Deep network aggregation-based fundus image focus segmentation method | |
Liu et al. | CT-UNet: Context-transfer-UNet for building segmentation in remote sensing images | |
CN110503078A (en) | A kind of remote face identification method and system based on deep learning | |
Fu et al. | A blind medical image denoising method with noise generation network | |
CN114973086A (en) | Video processing method and device, electronic equipment and storage medium | |
CN113763300A (en) | Multi-focus image fusion method combining depth context and convolution condition random field | |
Cui et al. | Remote sensing image recognition based on dual-channel deep learning network | |
CN116740547A (en) | Digital twinning-based substation target detection method, system, equipment and medium | |
CN114863450B (en) | Image processing method, device, electronic equipment and storage medium | |
CN113593007B (en) | Single-view three-dimensional point cloud reconstruction method and system based on variation self-coding | |
CN114972937A (en) | Feature point detection and descriptor generation method based on deep learning | |
CN114385883B (en) | Contour enhancement method for approximately simulating chapping method in style conversion | |
Zeng et al. | 3D plants reconstruction based on point cloud | |
Li et al. | Compact twice fusion network for edge detection |
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 | ||
CF01 | Termination of patent right due to non-payment of annual fee | ||
CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20190621 Termination date: 20211114 |