Low-light image enhancement method and system based on multi-mode cooperation, storage medium and equipment
By employing a multimodal collaborative low-light image enhancement method, utilizing shallow feature extraction, a dual-branch encoder network, and a state-space feature module, the modal differences and cross-scale issues in low-light image enhancement are addressed, achieving highly efficient image enhancement results.
Patent Information
- Application Number
- CN202511637497.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-10
- Publication Date
- 2026-02-06
AI Technical Summary
Existing low-light image enhancement methods suffer from problems such as ineffective elimination of modal differences, insufficient cross-scale feature interaction, weak long-range dependency modeling ability, and insufficient integration of modal advantages, resulting in poor image enhancement effects.
A low-light image enhancement method based on multimodal collaboration is adopted. Through a shallow feature extraction module, a dual-branch encoder-decoder network, an inconsistent weight learning module, a hierarchical cross-scale fusion module, and a state space feature module, the feature collaboration enhancement of low-light images and infrared images is achieved, including channel attention, pixel attention, cross-scale feature interaction, and adaptive weighted fusion.
It significantly improves the signal-to-noise ratio and brightness uniformity of images, restores details in dark areas, reduces modal conflicts and noise interference, meets the needs of real-time applications, and reduces deployment costs.
Smart Images

Figure CN121481869A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of computer vision and image processing technology, specifically relating to a low-light image enhancement method, system, storage medium, and device based on multimodal collaboration. Background Technology
[0002] In low-light environments, images are prone to problems such as insufficient brightness, loss of detail, and noise interference, which seriously affect the accuracy of subsequent image analysis (such as object detection and semantic segmentation). Traditional low-light image enhancement methods mostly rely on single-modal (visible light) processing, such as Retinex theoretical decomposition and histogram equalization. Although these methods can improve brightness, they are prone to introducing artifacts and color distortion, and it is difficult to recover details in dark areas.
[0003] With the development of deep learning, multimodal enhancement techniques (combining visible light and infrared images) have become a research hotspot. Infrared images are unaffected by low-light environments and can provide stable structural information, complementing the texture details of visible light images. However, existing multimodal low-light enhancement methods still have the following problems: 1. Modal differences are not effectively eliminated: The imaging principles of visible light and infrared images are different, and there are inherent differences in feature distribution. Existing methods often directly fuse features, resulting in noise or modal conflicts in the fusion results. 2. Insufficient cross-scale feature interaction: Low-light enhancement needs to take into account both global structure and local details, but existing cross-scale fusion is mostly single-scale interaction, which cannot achieve the hierarchical aggregation and optimization of features at different scales. 3. Weak ability to model long-range dependencies: Traditional methods rely on CNNs (which are insufficient for modeling long-range dependencies) or Transformers (which have high computational complexity), making it difficult to achieve a balance between efficiency and performance; 4. Modal advantages are not fully combined: Existing fusion strategies are mostly simple weighted or fixed rule fusion, which cannot adaptively balance the anti-interference ability of infrared images and the texture richness of visible light images; To address this, we propose a low-light image enhancement method, system, storage medium, and device based on multimodal collaboration. Summary of the Invention
[0004] The purpose of this invention is to provide a low-light image enhancement method, system, storage medium, and device based on multimodal collaboration to solve the problems mentioned in the background art.
[0005] To achieve the above objectives, the present invention provides the following technical solution: a low-light image enhancement method based on multimodal collaboration, comprising the following steps: Step 1: Obtain the low-light image and the corresponding infrared image. Input the two types of images into the shallow feature extraction module respectively. Through convolution operation combined with the synergistic enhancement of channel attention and pixel attention, the corresponding low-light shallow features and infrared shallow features are obtained. Step 2: Input the low-light shallow layer features and infrared shallow layer features into the dual-branch encoder-decoder network respectively. The encoder-decoder network, which is composed of stacked residual dual attention blocks, extracts the encoder features and decoder features of each branch step by step. Step 3: Eliminate the feature differences between low-light mode and infrared mode through the inconsistent weight learning module, and then perform multi-scale interaction and aggregation of encoder features and decoder features of the same scale through the hierarchical cross-scale fusion module to obtain cross-scale feature sequence. Step 4: Adaptively weightedly fuse the low-light cross-scale features and infrared cross-scale features corresponding to the cross-scale feature sequence using a complementary collaborative strategy to obtain weighted fused features; Step 5: Input the weighted fusion features into the state space feature module, use the Mamba state space modeling mechanism to perform bidirectional information interaction and feature enhancement, and output the enhanced fusion features; Step 6: Input the enhanced fusion features into the reconstruction decoder, and after stepwise upsampling and convolutional fusion processing, obtain the final low-light enhanced image.
[0006] Preferably, the specific implementation process of the shallow feature extraction module in step 1 is as follows: 1.1 Perform a 3×3 convolution operation on the input low-light image or infrared image to obtain the initial features. The calculation formula for the initial features is shown in formula (1): (1); Where I represents the input low-light image or infrared image; This represents a 3×3 convolution operation; This represents the initial features extracted by convolution; 1.2. The initial features are input into the channel attention module, and then processed sequentially through global average pooling, ReLU activation function, and Sigmoid activation function to generate channel weighted coefficients. The channel weighted features are obtained by element-wise multiplication. The initial feature input channel attention module is calculated by global average pooling as shown in formula (2): (2); Among them, z c This represents the channel feature vector obtained after global average pooling (GAP). Each element is a real number, and the dimension is B rows × C columns, where B represents the batch size and C represents the number of channels. GAP stands for Global Average Pooling Operation; The formula for calculating the channel weighting coefficient is shown in formula (3): (3); in, Represents the ReLU activation function; This represents the Sigmoid activation function; , r represents the compression factor; The formula for calculating the channel weighted feature by multiplying element by element is shown in formula (4). (4); Among them, s c This represents the channel weighting coefficients output by the channel attention module; This represents the element-wise multiplication operator; F (c) Indicates channel weighting characteristics; 1.3 Input the channel-weighted features into the pixel attention module, generate a pixel attention map through 7×7 convolution operation and Sigmoid activation function, and obtain the pixel enhancement features by element-wise multiplication. The calculation formula of the pixel enhancement features is shown in formula (5): (5); Among them, M s This represents the pixel attention map output by the pixel attention module. F s Indicates pixel enhancement features; The calculation formula for the pixel attention map is shown in formula (6): (6); Conv 7×7 (・) represents a 7×7 convolution operation; AugPool(・) indicates average pooling; MaxPool(・) represents maximum pooling. H and W represent the height and width of the feature map; R B×1×H×W This indicates that the pixel attention map is a real tensor with dimensions B batch × 1 single channel × H feature map height × W feature map width; 1.4. Pixel enhancement features are used as shallow compensation features and output. The shallow compensation features corresponding to the low-light image are called low-light shallow features. The shallow compensation features corresponding to the infrared image are infrared shallow features. The final formula for calculating the shallow compensation feature is shown in formula (7): (7); Where PA(・) represents the processing procedure of the pixel attention module; CA(・) represents the processing procedure of the channel attention module.
[0007] Preferably, in step 3, the specific implementation steps of the hierarchical cross-scale fusion module are as follows: 3.1 For the encoder features and decoder features of the nth layer, first perform element-wise addition, and then perform layer normalization to obtain the mixed features. The calculation formula for the mixed features is shown in formula (8): (8); Where n represents the feature level, n∈{1,2,3}; Represents the features of the nth layer encoder; Represents the features of the nth layer decoder; LN(・) denotes the layer normalization operation; This represents the hybrid feature resulting from the fusion of encoder and decoder features; 3.2. For the mixed features, average pooling downsampling is applied to scales s∈{1,2,4} respectively. Query vector, key vector, and value vector are constructed through linear mapping. Relative position bias is introduced to calculate the attention matrix. The interaction output of scale s is obtained by weighting the value vector based on the attention matrix. The calculation formula for the interaction output of scale s is shown in formula (9): (9); This represents the feature interaction output at the nth scale s; Let represent the attention matrix at the nth scale s; This represents the value vector of the nth scale s; s represents the downsampling scale, s∈{1,2,4}; The formula for calculating the attention matrix is shown in formula (10): (10); Softmax(・) represents the normalization function; This represents the query vector at the nth level scale s; Represents the key vector at the nth scale s; express and Feature Dimensions Indicates relative position offset; The calculation formulas for the query vector, key vector, and value vector are shown in formulas (11), (12), and (13): (11); (12); (13); Linear(・) represents a linear mapping operation; 3.3. Weighted aggregation of the interactive outputs at different scales, combined with residual connections and layer normalization, yields cross-scale features. The calculation formula for cross-scale features is shown in formula (14): (14); C n This represents the cross-scale fusion feature of the nth layer; O n This represents a weighted aggregation of interactive outputs at different scales. The calculation formula for the weighted aggregation of interactive outputs at different scales is shown in formula (15): (15); , and These represent the interactive outputs corresponding to scales s=1, 2, and 4, respectively. , and This represents the learnable weighted coefficients, and + + =1; 3.4 By stacking the cross-scale features from layers 1 to 3 layer by layer, a cross-scale feature sequence {C1, C2, C3} is formed. The low-light branch corresponds to the cross-scale feature sequence. Infrared branch corresponds to cross-scale feature sequence .
[0008] Preferably, the specific implementation steps of the complementary and cooperative strategy in step 4 are as follows: 4.1 Low-light cross-scale features of the nth layer in the cross-scale feature sequence With infrared cross-scale features First, scale alignment and channel number unification are performed, and then the features are restored to the original spatial dimension through the mapping function. The calculation formula of the feature dimension restoration mapping function is shown in formula (16): (16); This represents the feature dimension restoration mapping function; This represents a 1×1 convolution operation; 4.2 Low-light features after dimensionality restoration With infrared features After channel concatenation, pixel-level gate weights are generated by 3×3 convolution and Sigmoid activation function. The formula for calculating the pixel-level gate weights is shown in formula (17): (17); W g Indicates the parameters of the 3×3 convolution kernel; This represents the convolution operation; g n Represents pixel-level gating weights; 4.3 Calculate the weighted fusion features of the nth layer using the weighted fusion formula. The weighted fusion formula is shown in formula (18): (18); This represents the weighted fusion feature of the nth layer; This represents the element-wise multiplication operator; This represents learnable complementary parameters.
[0009] Preferably, the specific implementation steps of the state space feature module in step 5 are as follows: 5.1 Weighted fusion features Flatten and rearrange into a token sequence X∈R B×T×D The input representation is obtained through linear transformation, then the linearly transformed input representation is Z=XW in ; Where X represents the token sequence feature after flattening and rearranging, B is the batch size, T is the number of tokens, and D is the feature dimension; W in Represents the parameters of the linear transformation matrix; 5.2. A bidirectional state-space model is used to model the linear transformation input representation Z. The modeling formulas are shown in formulas (19) and (20): Forward scan: (19); Backward scan: (20); in, , , Represents the learnable state space parameters of the forward scan; , , Represents the learnable state-space parameters for backward scanning; h t Represents the hidden state at time t; Z t Let Z be the feature sequence of the t-th token; This indicates the output features at time t during the forward scan; This indicates the output features at time t during the backward scan; 5.3 Concatenating the forward output sequence With backward output sequence After linear transformation, the bidirectional fused output is obtained. The calculation formula for the bidirectional fused output is shown in formula (21): (twenty one); W out This indicates the parameters of the output linear transformation matrix; Y represents the output feature after bidirectional fusion; 5.4. The bidirectional fusion output feature Y is sequentially input into the channel attention module and the pixel attention module for secondary enhancement. Combined with the residual connection, the enhanced fusion feature is obtained. The calculation formula of the enhanced fusion feature is shown in formula (22): (twenty two); F enhanced This represents the final enhanced fusion feature.
[0010] Preferably, the specific implementation steps of image reconstruction in step 6 are as follows: 6.1 First, convert the enhanced fused features from token sequence format to feature map format to ensure that the features can adapt to the input requirements of subsequent upsampling and convolution operations; 6.2 First-level upsampling and fusion: The feature map is upsampled using a transposed convolution with a kernel size of 3×3, a stride of 2, and padding of 1, which doubles the height and width of the feature map and halves the number of channels. The upsampled features are then residually concatenated with the intermediate features of the corresponding scale output by the encoding and decoding network, and then processed by layer normalization and ReLU activation function to obtain the first-level fusion optimized features. 6.3 Second-level upsampling and fusion: Repeat the transposed convolution upsampling with the same parameters as in step 6.2 on the features output from the first level, so that the height and width of the feature map are expanded to twice their original size again, and the number of channels is halved again; perform residual connection between the upsampled features and the intermediate features at the corresponding scale, and after layer normalization and ReLU activation function processing, obtain the second-level fused and optimized features; 6.4 Third-level upsampling and fusion: The features output from the second level are upsampled by transposed convolution with the same parameters as the first two levels, which further expands the height and width of the feature map to twice the original size, while the number of channels is halved. The upsampled features are then residually connected with the intermediate features at the corresponding scale. After layer normalization and ReLU activation, the optimized features of the third level fusion are obtained. 6.5 Channel Mapping and Output: First, the features after the third-level fusion are optimized for detail through 3×3 convolution, and a 32-channel feature map is output. Then, the 32-channel features are mapped to a 3-channel RGB image format through 1×1 convolution, and finally a low-light enhanced image with the same size as the original input image is obtained.
[0011] A low-light image enhancement system based on multimodal collaboration, applied to a low-light image enhancement method based on multimodal collaboration, includes: The feature extraction module receives the low-light image and the corresponding infrared image, and performs convolution operation and channel attention and pixel attention co-enhancement through the shallow feature extraction module to output low-light shallow features and infrared shallow features. The encoding and decoding module constructs a dual-branch encoder-decoder network based on residual dual attention blocks, performs multi-scale feature extraction on low-light shallow features and infrared shallow features respectively, and outputs the encoder features and decoder features of each branch. The modality fusion module eliminates modal feature differences through the inconsistent weight learning module, then achieves multi-scale feature interaction aggregation through the hierarchical cross-scale fusion module, and finally performs adaptive weighted fusion through a complementary collaborative strategy to output weighted fusion features. The feature enhancement module performs Mamba bidirectional state space modeling and attention enhancement on the weighted fused features through the state space feature module, and outputs the enhanced fused features. The image reconstruction module is configured to perform stepwise upsampling, residual fusion, and channel mapping processing on the enhanced fusion features through a reconstruction decoder, and output the final low-light enhanced image.
[0012] A computer-readable storage medium storing a computer program that, when executed by a processor, implements all steps of a low-light image enhancement method based on multimodal collaboration.
[0013] An electronic device includes a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements a low-light image enhancement method based on multimodal collaboration.
[0014] Preferably, the electronic device further includes: The image acquisition unit is configured to acquire low-light images and corresponding infrared images in low-light environments; The data processing unit is configured to execute the computer program as the processor to perform low-light enhancement processing on the image acquired by the image acquisition unit. The image output unit is configured to receive the low-light enhanced image output by the data processing unit and display or store it.
[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. Improved modal fusion accuracy, completely resolving modal conflicts and noise interference issues: This invention achieves precise optimization of modality fusion through the synergistic effect of an inconsistent weight learning module and a complementary collaborative strategy: The inconsistent weight learning module learns by modeling the distribution differences between the two modal features and adaptively adjusting the feature weights to eliminate modal conflicts, thus laying a clean feature foundation for subsequent fusion. The complementary and collaborative strategy enables pixel-level gating weights and complementary interaction terms to dynamically balance the advantages of infrared images in resisting low-light interference and the advantages of visible light images in terms of texture details according to the scene, and to actively explore the collaborative information of the two modes, avoiding the waste of advantages caused by single weighted fusion. The signal-to-noise ratio of the enhanced image is significantly improved, the noise suppression rate in the modal conflict region is improved by more than 30%, while the structural stability of the infrared image and the texture richness of the visible light image are fully preserved. 2. Full utilization of cross-scale features, taking into account both global structure and local detail restoration: The hierarchical cross-scale fusion module of this invention constructs a complete technical approach of same-scale fusion, cross-scale interaction, and global aggregation through a multi-scale cross-attention mechanism. First, the features of the encoder and decoder at the same scale are mixed and normalized to ensure the consistency of single-scale features; Then, through multi-scale (1x, 2x, 4x) downsampling and cross-attention interaction, precise coupling of features at different scales is achieved; Finally, by stacking layers one by one, a cross-scale feature sequence is formed, allowing global structural information and local detail information to fully complement each other at each level. The brightness uniformity of the enhanced image is improved by more than 25%, and the recovery rate of dark details (such as textures and edges in low-light environments) is improved by 40%, avoiding the problems of overexposure in bright areas and loss of dark details in existing methods. 3. Highly efficient long-range dependency modeling, balancing performance and inference efficiency: The state-space feature module of this invention introduces the Mamba state-space modeling mechanism to achieve efficient modeling of long-range dependencies: A bidirectional state-space model is used to perform forward and backward scanning of the fused features, fully capturing long-distance feature associations and improving the robustness of feature representation; By combining channel attention and pixel attention for secondary enhancement, the accuracy of local features is preserved while strengthening long-range dependencies; It improves the recovery accuracy of long-range structures (such as distant outlines and continuous textures in low-light scenes) by 20%, while the inference time of a single image is controlled within 50ms, meeting the needs of real-time scenarios such as security monitoring and autonomous driving. 4. End-to-end process optimization reduces application barriers and deployment costs: This invention employs a complete end-to-end technology encompassing shallow feature extraction, deep encoding / decoding, modality fusion, feature enhancement, and image reconstruction. No additional preprocessing or post-processing steps are required; simply input low-light and infrared images to output enhanced results. The operation is convenient. The modules work together in a deep collaboration to form a closed loop of feature extraction, optimization, fusion, enhancement and reconstruction, avoiding feature loss between modules; The network parameters are reasonably designed, the model size is moderate, and it can be deployed on edge devices (such as embedded cameras and vehicle terminals).
[0016] Deployment costs are reduced by 40%, it is compatible with different hardware platforms, and it can run stably without the need for professional personnel to debug, significantly improving the feasibility of technology implementation. It can be widely used in nighttime security monitoring, vehicle vision systems, mobile device shooting, low-light enhancement of medical images, etc., providing high-quality input for subsequent vision tasks and promoting the application of computer vision technology in low-light environments. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of the method flow of the present invention; Figure 2 This is a schematic diagram of a low-light image in a specific application embodiment of the present invention; Figure 3 This is a schematic diagram of the actual exposure of a low-light image in a specific application embodiment of the present invention; Figure 4 This is a schematic diagram of a low-light image processed by the present invention to enhance the low-light image in a specific application embodiment of the present invention. Detailed Implementation
[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0019] Please see Figure 1 The low-light image enhancement method based on multimodal collaboration provided by this invention includes the following steps: Step 1: Obtain the low-light image and the corresponding infrared image. Input the two types of images into the shallow feature extraction module respectively. Through convolution operation combined with the synergistic enhancement of channel attention and pixel attention, the corresponding low-light shallow features and infrared shallow features are obtained. The specific implementation process of the shallow feature extraction module in step 1 is as follows: 1.1 Perform a 3×3 convolution operation on the input low-light image or infrared image to obtain the initial features. The calculation formula for the initial features is shown in formula (1): (1); Where I represents the input low-light image or infrared image; This represents a 3×3 convolution operation; This represents the initial features extracted by convolution; 1.2. The initial features are input into the channel attention module, and then processed sequentially through global average pooling, ReLU activation function, and Sigmoid activation function to generate channel weighted coefficients. The channel weighted features are obtained by element-wise multiplication. The initial feature input channel attention module is calculated by global average pooling as shown in formula (2): (2); Among them, z c This represents the channel feature vector obtained after global average pooling (GAP). Each element is a real number, and the dimension is B rows × C columns, where B represents the batch size and C represents the number of channels. GAP stands for Global Average Pooling Operation; The formula for calculating the channel weighting coefficient is shown in formula (3): (3); in, Represents the ReLU activation function; This represents the Sigmoid activation function; , r represents the compression factor; The formula for calculating the channel weighted feature by multiplying element by element is shown in formula (4). (4); Among them, s c This represents the channel weighting coefficients output by the channel attention module; This represents the element-wise multiplication operator; F (c) Indicates channel weighting characteristics; 1.3 Input the channel-weighted features into the pixel attention module, generate a pixel attention map through 7×7 convolution operation and Sigmoid activation function, and obtain the pixel enhancement features by element-wise multiplication. The calculation formula of the pixel enhancement features is shown in formula (5): (5); Among them, M s This represents the pixel attention map output by the pixel attention module. F s Indicates pixel enhancement features; The calculation formula for the pixel attention map is shown in formula (6): (6); Conv 7×7 (・) represents a 7×7 convolution operation; AugPool(・) indicates average pooling; MaxPool(・) represents maximum pooling. H and W represent the height and width of the feature map; R B×1×H×W This indicates that the pixel attention map is a real tensor with dimensions B batch × 1 single channel × H feature map height × W feature map width; 1.4. Pixel enhancement features are used as shallow compensation features and output. The shallow compensation features corresponding to the low-light image are called low-light shallow features. The shallow compensation features corresponding to the infrared image are infrared shallow features. The final formula for calculating the shallow compensation feature is shown in formula (7): (7); Where PA(・) represents the processing procedure of the pixel attention module; CA(・) represents the processing procedure of the channel attention module; Step 2: Input the low-light shallow layer features and infrared shallow layer features into the dual-branch encoder-decoder network respectively. The encoder-decoder network, which is composed of stacked residual dual attention blocks, extracts the encoder features and decoder features of each branch step by step. Step 3: Eliminate the feature differences between low-light mode and infrared mode through the inconsistent weight learning module, and then perform multi-scale interaction and aggregation of encoder features and decoder features of the same scale through the hierarchical cross-scale fusion module to obtain cross-scale feature sequence. The specific implementation steps of the hierarchical cross-scale fusion module in step 3 are as follows: 3.1 For the encoder features and decoder features of the nth layer, first perform element-wise addition, and then perform layer normalization to obtain the mixed features. The calculation formula for the mixed features is shown in formula (8): (8); Where n represents the feature level, n∈{1,2,3}; Represents the features of the nth layer encoder; Represents the features of the nth layer decoder; LN(・) denotes the layer normalization operation; This represents the hybrid feature resulting from the fusion of encoder and decoder features; 3.2. For the mixed features, average pooling downsampling is applied to scales s∈{1,2,4} respectively. Query vector, key vector, and value vector are constructed through linear mapping. Relative position bias is introduced to calculate the attention matrix. The interaction output of scale s is obtained by weighting the value vector based on the attention matrix. The calculation formula for the interaction output of scale s is shown in formula (9): (9); This represents the feature interaction output at the nth scale s; Let represent the attention matrix at the nth scale s; This represents the value vector of the nth scale s; s represents the downsampling scale, s∈{1,2,4}; The formula for calculating the attention matrix is shown in formula (10): (10); Softmax(・) represents the normalization function; This represents the query vector at the nth level scale s; Represents the key vector at the nth scale s; express and Feature Dimensions Indicates relative position offset; The calculation formulas for the query vector, key vector, and value vector are shown in formulas (11), (12), and (13): (11); (12); (13); Linear(⋅) represents a linear mapping operation; 3.3. Weighted aggregation of the interactive outputs at different scales, combined with residual connections and layer normalization, yields cross-scale features. The calculation formula for cross-scale features is shown in formula (14): (14); C n This represents the cross-scale fusion feature of the nth layer; O n This represents a weighted aggregation of interactive outputs at different scales. The calculation formula for the weighted aggregation of interactive outputs at different scales is shown in formula (15): (15); , and These represent the interactive outputs corresponding to scales s=1, 2, and 4, respectively. , and This represents the learnable weighted coefficients, and + + =1; 3.4 By stacking the cross-scale features from layers 1 to 3 layer by layer, a cross-scale feature sequence {C1, C2, C3} is formed. The low-light branch corresponds to the cross-scale feature sequence. Infrared branch corresponds to cross-scale feature sequence ; Step 4: Adaptively weightedly fuse the corresponding low-light cross-scale features and infrared cross-scale features in the cross-scale feature sequence using a complementary collaborative strategy to obtain weighted fused features; The specific implementation steps of the complementary and cooperative strategy in step 4 are as follows: 4.1 Low-light cross-scale features of the nth layer in the cross-scale feature sequence With infrared cross-scale features First, scale alignment and channel number unification are performed, and then the features are restored to the original spatial dimension through the mapping function. The calculation formula of the feature dimension restoration mapping function is shown in formula (16): (16); This represents the feature dimension restoration mapping function; This represents a 1×1 convolution operation; 4.2 Low-light features after dimensionality restoration With infrared features After channel concatenation, pixel-level gate weights are generated by 3×3 convolution and Sigmoid activation function. The formula for calculating the pixel-level gate weights is shown in formula (17): (17); W g Indicates the parameters of the 3×3 convolution kernel; This represents the convolution operation; g n Represents pixel-level gating weights; 4.3 Calculate the weighted fusion features of the nth layer using the weighted fusion formula. The weighted fusion formula is shown in formula (18): (18); This represents the weighted fusion feature of the nth layer; This represents the element-wise multiplication operator; Indicates learnable complementary parameters; Step 5: Input the weighted fusion features into the state space feature module, use the Mamba state space modeling mechanism to perform bidirectional information interaction and feature enhancement, and output the enhanced fusion features; The specific implementation steps of the state space feature module in step 5 are as follows: 5.1 Weighted fusion features Flatten and rearrange into a token sequence X∈R B×T×D The input representation is obtained through linear transformation, then the linearly transformed input representation is Z=XW in ; Where X represents the token sequence feature after flattening and rearranging, B is the batch size, T is the number of tokens, and D is the feature dimension; W in Represents the parameters of the linear transformation matrix; 5.2. A bidirectional state-space model is used to model the linear transformation input representation Z. The modeling formulas are shown in formulas (19) and (20): Forward scan: (19); Backward scan: (20); in, , , Represents the learnable state space parameters of the forward scan; , , Represents the learnable state-space parameters for backward scanning; h t Represents the hidden state at time t; Z t Let Z be the feature sequence of the t-th token; This indicates the output features at time t during the forward scan; This indicates the output features at time t during the backward scan; 5.3 Concatenating the forward output sequence With backward output sequence After linear transformation, the bidirectional fused output is obtained. The calculation formula for the bidirectional fused output is shown in formula (21): (twenty one); W out This indicates the parameters of the output linear transformation matrix; Y represents the output feature after bidirectional fusion; 5.4. The bidirectional fusion output feature Y is sequentially input into the channel attention module and the pixel attention module for secondary enhancement. Combined with the residual connection, the enhanced fusion feature is obtained. The calculation formula of the enhanced fusion feature is shown in formula (22): (twenty two); F enhanced This represents the final enhanced fusion feature; Step 6: Input the enhanced fusion features into the reconstruction decoder, and after stepwise upsampling and convolutional fusion processing, obtain the final low-light enhanced image; The specific steps for image reconstruction in step 6 are as follows: 6.1 First, convert the enhanced fused features from token sequence format to feature map format to ensure that the features can adapt to the input requirements of subsequent upsampling and convolution operations; 6.2 First-level upsampling and fusion: The feature map is upsampled using a transposed convolution with a kernel size of 3×3, a stride of 2, and padding of 1, which doubles the height and width of the feature map and halves the number of channels. The upsampled features are then residually concatenated with the intermediate features of the corresponding scale output by the encoding and decoding network, and then processed by layer normalization and ReLU activation function to obtain the first-level fusion optimized features. 6.3 Second-level upsampling and fusion: Repeat the transposed convolution upsampling with the same parameters as in step 6.2 on the features output from the first level, so that the height and width of the feature map are expanded to twice their original size again, and the number of channels is halved again; perform residual connection between the upsampled features and the intermediate features at the corresponding scale, and after layer normalization and ReLU activation function processing, obtain the second-level fused and optimized features; 6.4 Third-level upsampling and fusion: The features output from the second level are upsampled by transposed convolution with the same parameters as the first two levels, which further expands the height and width of the feature map to twice the original size, while the number of channels is halved. The upsampled features are then residually connected with the intermediate features at the corresponding scale. After layer normalization and ReLU activation, the optimized features of the third level fusion are obtained. 6.5 Channel Mapping and Output: First, the features after the third-level fusion are optimized for detail through 3×3 convolution, and a 32-channel feature map is output. Then, the 32-channel features are mapped to a 3-channel RGB image format through 1×1 convolution, and finally a low-light enhanced image with the same size as the original input image is obtained.
[0020] This embodiment provides a low-light image enhancement system based on multimodal collaboration, applied to a low-light image enhancement method based on multimodal collaboration, including: The feature extraction module receives the low-light image and the corresponding infrared image, and performs convolution operation and channel attention and pixel attention co-enhancement through the shallow feature extraction module to output low-light shallow features and infrared shallow features. The encoding and decoding module constructs a dual-branch encoder-decoder network based on residual dual attention blocks, performs multi-scale feature extraction on low-light shallow features and infrared shallow features respectively, and outputs the encoder features and decoder features of each branch. The modality fusion module eliminates modal feature differences through the inconsistent weight learning module, then achieves multi-scale feature interaction aggregation through the hierarchical cross-scale fusion module, and finally performs adaptive weighted fusion through a complementary collaborative strategy to output weighted fusion features. The feature enhancement module performs Mamba bidirectional state space modeling and attention enhancement on the weighted fused features through the state space feature module, and outputs the enhanced fused features. The image reconstruction module is configured to perform stepwise upsampling, residual fusion, and channel mapping processing on the enhanced fusion features through a reconstruction decoder, and output the final low-light enhanced image.
[0021] This embodiment provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements all the steps of a low-light image enhancement method based on multimodal collaboration.
[0022] This embodiment provides an electronic device, including a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements a low-light image enhancement method based on multimodal collaboration. Also includes: The image acquisition unit is configured to acquire low-light images and corresponding infrared images in low-light environments; The data processing unit is configured to execute a computer program as a processor to perform low-light enhancement processing on the image acquired by the image acquisition unit. The image output unit is configured to receive the low-light enhanced image output by the data processing unit and display or store it.
[0023] Specific application examples of the present invention: like Figure 2 As shown, it is a low-light image. After processing by the method of this invention, the target exposure image is obtained, i.e. Figure 4 As shown, it can be seen from the visual effect that... Figure 4 Significant illumination enhancement was achieved, not only restoring visible information in dark areas but also providing excellent enhancement in texture and detail, comparable to the actual exposed image. Figure 3 Compared to (as shown), there is almost no significant difference. This invention can be used to obtain reliable target exposure images, providing support for subsequent high-level vision tasks such as target detection and semantic segmentation.
[0024] In summary, this invention employs a shallow feature extraction module, a hierarchical cross-scale fusion module, a complementary collaborative fusion module, and a state space feature module to jointly construct the IMENet network, thereby fully utilizing and collaboratively modeling the multimodal information of low-light and infrared images. During the enhancement process, this invention can not only effectively utilize the compensation effect of infrared mode on low-light mode, but also extract global and local information at different levels through cross-scale interaction, thus enhancing the restoration effect of low-light images. This invention introduces a complementary and collaborative mechanism to avoid the common problems of detail loss and noise amplification in the process of single-modal enhancement, so that the enhanced image performs better in terms of brightness balance, texture detail fidelity and noise suppression. Furthermore, through state space modeling, this invention enhances the long-range dependency modeling capability while maintaining structural information, making the feature representation after cross-modal fusion more stable and robust. This invention, by reconstructing the decoder and convolutional mapping to output the enhanced image, can obtain low-light enhancement results with normal exposure and good restoration effect, providing more reliable input for subsequent high-level vision tasks such as object detection and semantic segmentation.
[0025] This invention addresses the technical challenges of existing low-light image enhancement methods in areas such as modal fusion, cross-scale feature utilization, and long-range dependency modeling, based on multimodal synergy. Compared to existing technologies, it offers the following significant advantages: I. Improved precision in modal fusion, completely resolving modal conflicts and noise interference issues: Existing multimodal enhancement methods often directly fuse low-light visible light and infrared features, failing to effectively address the feature distribution conflicts caused by the differences in the imaging principles of the two modalities, and easily introducing fusion noise and artifacts; This invention achieves precise optimization of modality fusion through the synergistic effect of an inconsistent weight learning module and a complementary collaborative strategy: The inconsistent weight learning module learns by modeling the distribution differences between the two modal features and adaptively adjusting the feature weights to eliminate modal conflicts, thus laying a clean feature foundation for subsequent fusion. The complementary and collaborative strategy enables pixel-level gating weights and complementary interaction terms to dynamically balance the advantages of infrared images in resisting low-light interference and the advantages of visible light images in terms of texture details according to the scene, and to actively explore the collaborative information of the two modes, avoiding the waste of advantages caused by single weighted fusion. The signal-to-noise ratio of the enhanced image is significantly improved, the noise suppression rate in the modal conflict region is improved by more than 30%, while the structural stability of the infrared image and the texture richness of the visible light image are fully preserved. II. Full utilization of cross-scale features, taking into account both global structure and local detail restoration: Low-light image enhancement requires the simultaneous restoration of global brightness balance and local detail clarity. Existing methods mostly employ single-scale fusion or simple cross-scale stitching, which cannot achieve step-by-step feature optimization. The hierarchical cross-scale fusion module of this invention constructs a complete technical approach of same-scale fusion, cross-scale interaction, and global aggregation through a multi-scale cross-attention mechanism. First, the features of the encoder and decoder at the same scale are mixed and normalized to ensure the consistency of single-scale features; Then, through multi-scale (1x, 2x, 4x) downsampling and cross-attention interaction, precise coupling of features at different scales is achieved; Finally, by stacking layers one by one, a cross-scale feature sequence is formed, allowing global structural information and local detail information to fully complement each other at each level. The brightness uniformity of the enhanced image is improved by more than 25%, and the recovery rate of dark details (such as textures and edges in low-light environments) is improved by 40%, avoiding the problems of overexposure in bright areas and loss of dark details in existing methods. III. High efficiency in long-range dependency modeling, balancing performance and inference efficiency: In traditional low-light enhancement methods, CNNs struggle to model long-range feature associations. While Transformers can solve this problem, their computational complexity is high (quadratic complexity), making them unsuitable for real-time applications. The state-space feature module of this invention introduces the Mamba state-space modeling mechanism to achieve efficient modeling of long-range dependencies: A bidirectional state-space model is used to perform forward and backward scanning of the fused features, fully capturing long-distance feature associations and improving the robustness of feature representation; By combining channel attention and pixel attention for secondary enhancement, the accuracy of local features is preserved while strengthening long-range dependencies; It improves the recovery accuracy of long-range structures (such as distant outlines and continuous textures in low-light scenes) by 20%, while the inference time of a single image is controlled within 50ms, meeting the needs of real-time scenarios such as security monitoring and autonomous driving. IV. End-to-end process optimization to reduce application barriers and deployment costs: Some existing multimodal enhancement methods rely on preprocessing steps such as Retinex decomposition and illuminance estimation, which are cumbersome and prone to introducing preprocessing errors, increasing the application threshold. This invention employs a complete end-to-end technology encompassing shallow feature extraction, deep encoding / decoding, modality fusion, feature enhancement, and image reconstruction. No additional preprocessing or post-processing steps are required; simply input low-light and infrared images to output enhanced results. The operation is convenient. The modules work together in a deep collaboration to form a closed loop of feature extraction, optimization, fusion, enhancement and reconstruction, avoiding feature loss between modules; The network parameters are reasonably designed, the model size is moderate, and it can be deployed on edge devices (such as embedded cameras and vehicle terminals).
[0026] Deployment costs are reduced by 40%, it is compatible with different hardware platforms, and it can run stably without the need for professional personnel to debug, significantly improving the feasibility of technology implementation. It can be widely used in nighttime security monitoring, vehicle vision systems, mobile device shooting, low-light enhancement of medical images, etc., providing high-quality input for subsequent vision tasks and promoting the application of computer vision technology in low-light environments.
[0027] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A low-light image enhancement method based on multi-modal collaboration, characterized in that, The method comprises the following steps: Step 1, obtaining a low-light image and a corresponding infrared image, inputting the two types of images into a shallow feature extraction module respectively, and obtaining corresponding low-light shallow features and infrared shallow features through convolution operation combined with synergistic enhancement of channel attention and pixel attention; Step 2, inputting the low-light shallow features and the infrared shallow features into a double-branch encoder-decoder network respectively, and gradually extracting the encoder features and the decoder features of each branch by the encoder-decoder network composed of residual double attention block stacking; Step 3, eliminating the feature difference between the low-light mode and the infrared mode through an inconsistent weight learning module, and then performing multi-scale interaction and aggregation on the encoder features and the decoder features of the same scale through a hierarchical cross-scale fusion module to obtain a cross-scale feature sequence; Step 4, using a complementary synergy strategy to adaptively weight and fuse corresponding low-light cross-scale features and infrared cross-scale features in the cross-scale feature sequence to obtain a weighted fusion feature; Step 5, inputting the weighted fusion feature into a state space feature module, performing bidirectional information interaction and feature enhancement by using a Mamba state space modeling mechanism, and outputting an enhanced fusion feature; Step 6, inputting the enhanced fusion feature into a reconstruction decoder, performing gradual upsampling and convolution fusion processing to obtain a final low-light enhanced image.
2. The low-light image enhancement method based on multi-modal collaboration according to claim 1, characterized in that: The specific implementation process of the shallow feature extraction module in step 1 is as follows: 1.1, performing convolution operation on the input low-light image or infrared image to obtain initial features, and a calculation formula of the initial features is shown as formula (1): Convolution operation, get the initial features, the calculation formula of the initial features is shown as formula (1): (1); Wherein, I represents the input low-light image or infrared image; denotes convolution operation; denotes the initial feature extracted by convolution; 1.2, input the initial feature into the channel attention module, and generate the channel weighting coefficient through global average pooling, ReLU activation function and Sigmoid activation function in turn, and obtain the channel weighted feature by element-wise multiplication: Wherein, the initial feature is input into the channel attention module, and the calculation formula of the global average pooling is as shown in formula (2): (2); wherein z c represents a channel feature vector obtained after global average pooling GAP, each element of which is a real number and the dimension of which is , B represents batch size, and C represents channel number; GAP represents the global average pooling operation; The calculation formula of the channel weighting coefficient is as shown in formula (3): (3); wherein, denotes a ReLU activation function; denotes a sigmoid activation function; , , r represents the compression factor; The calculation formula of the channel weighted feature obtained by element-wise multiplication is as shown in formula (4) (4); wherein s c represents the channel weighting coefficients output by the channel attention module; represents an element-wise multiplication operator; F (c) representing a channel weighting feature; 1.
3. Input the channel-weighted features into the pixel attention module, and then... Convolution operations and the Sigmoid activation function generate pixel attention maps. Pixel enhancement features are obtained by element-wise multiplication. The calculation formula for pixel enhancement features is shown in formula (5): (5); wherein M s represents the pixel attention map output by the pixel attention module; F s representing a pixel enhancement feature; The calculation formula of the pixel attention map is as shown in formula (6): (6); denotes convolution operation; denotes an average pooling process; denotes a max-pooling process; H and W represent the height and width of the feature map; representing the pixel attention map is a real tensor; 1.4, the pixel enhancement feature is taken as a shallow layer compensation feature and output, the shallow layer compensation feature corresponding to the low light image is a low light shallow layer feature , the shallow layer compensation feature corresponding to the infrared image is an infrared shallow layer feature , and the calculation formula of the final shallow layer compensation feature is shown in formula (7): (7); wherein, represents the processing procedure of the pixel attention module; represents the processing procedure of the channel attention module.
3. The low-light image enhancement method based on multi-modal collaboration according to claim 2, characterized in that: In step 3, the specific implementation steps of the hierarchical cross-scale fusion module are as follows: 3.1, for the encoder features and the decoder features of the nth layer, first perform element-wise addition operation, and then perform layer normalization processing to obtain mixed features, and the calculation formula of the mixed features is as shown in formula (8): (8); wherein n represents a feature level, ; represents the n-th layer encoder feature; represents the nth layer decoder feature; Presentation layer normalization operations; represents the hybrid feature after the fusion of the encoder feature and the decoder feature; 3.
2. Apply different scales to the mixed features. Average pooling downsampling is used to construct query vector, key vector and value vector respectively through linear mapping. The attention matrix is calculated by introducing relative position bias. The interaction output of scale s is obtained by weighting the value vector based on the attention matrix. The calculation formula of the interaction output of scale s is shown in formula (9): (9); a characteristic interaction output representing a scale s of the n-th layer; an attention matrix representing a scale s of the n-th layer; a vector representing the value of the scale s of the n-th layer; s denotes a down-sampling scale, ; The calculation formula of the attention matrix is as shown in formula (10): (10); denotes a normalization function; query vector representing the scale s of the n-th layer; a key vector representing the scale s of the n-th layer; representing with characteristic dimensions; represents a relative position bias; The calculation formula of the query vector, the key vector and the value vector is as shown in formula (11), (12) and (13): (11); (12); (13); denotes a linear mapping operation; 3.3, weight and aggregate the interaction outputs of different scales, and then combine residual connection and layer normalization processing to obtain cross-scale features, and the calculation formula of the cross-scale features is as shown in formula (14): (14); C n is the cross-scale fusion feature of the nth layer; O n represents an interaction output weighted aggregation of different scales; The calculation formula of the weight aggregation of the interaction outputs of different scales is as shown in formula (15): (15); , and denote the interaction outputs corresponding to scales s = 1, 2, 4, respectively; 、 and denote learnable weighting coefficients, and + + = 1; 3.4, forming a cross-scale feature sequence by layer-by-layer stacking of the cross-scale features of the first to third layers , the low light branch corresponds to the cross-scale feature sequence , the infrared branch corresponds to the cross-scale feature sequence .
4. The low-light image enhancement method based on multi-modal collaboration according to claim 3, characterized in that: The specific implementation steps of the complementary synergy strategy in step 4 are as follows: 4.1, low-light cross-scale feature of the n-th layer in the cross-scale feature sequence with the infrared cross-scale feature , and then the feature is restored to the original spatial dimension through a mapping function. The calculation formula of the feature dimension restoration mapping function is shown in equation (16): (16); representing a feature dimension reduction mapping function; denotes convolution operation; 4.2, low-light features after dimension reduction with infrared features channel concatenation, and convolution operation and sigmoid activation function to generate pixel-level gating weights, and the calculation formula of the pixel-level gating weights is shown in equation (17): (17); W g indicates convolution kernel parameters; denotes a convolution operation; g n represents a pixel-level gating weight; 4.3, calculate the nth layer weighted fusion feature by the weighted fusion formula, and the weighted fusion formula is as shown in formula (18): (18); represents the n-th layer weighted fused feature; represents an element-wise multiplication operator; denote learnable complementary parameters.
5. The low-light image enhancement method based on multi-modal collaboration according to claim 4, characterized in that: The specific implementation steps of the state space feature module in step 5 are as follows: 5.1, the weighted fused features flattened and reordered into a token sequence , the linearly transformed input representation Z = XW in ; Wherein, X represents the flattened and rearranged token sequence feature, B is the batch size, T is the token number, and D is the feature dimension; W in denotes a linear transformation matrix parameter; 5.2, the linear transformation input representation Z is modeled using a bidirectional state space model, and the modeling formulas are shown in formulas (19) and (20): Forward scan: (19); Backward scan: (20); wherein, , , denote the learnable state space parameters for the forward scan; , , denote the learnable state space parameters for the backward scan; h t denotes the hidden state at time t; Z t is the t-th token feature sequence for the input representation Z; represents the output feature at time t for the forward scan; represents the output characteristic at time t of the backward scan; 5.3, concatenating the forward output sequence with the backward output sequence , and then linearly transforming to obtain the bidirectional fused output, the calculation formula of the bidirectional fused output is shown as formula (21): (21); W out represents an output linear transformation matrix parameter; Y represents the output feature after bidirectional fusion; 5.4, the bidirectional fusion output feature Y is sequentially input into the channel attention module and the pixel attention module for secondary enhancement, and the enhanced fusion feature is obtained through residual connection, and the calculation formula of the enhanced fusion feature is shown in formula (22): (22); F enhanced denotes the final enhanced fused feature.
6. The low-light image enhancement method based on multi-modal collaboration according to claim 5, characterized in that: The specific implementation steps of the image reconstruction in step 6 are as follows: 6.1, first convert the enhanced fusion feature from the token sequence format to the feature map format to ensure that the feature can adapt to the input requirements of the subsequent upsampling and convolution operation; 6.2, first level upsampling and fusion: upsampling is performed on the feature map using transpose convolution with a kernel size of 2, a step size of 2, and padding of 1, so that the height and width of the feature map are both expanded to twice the original size, and the number of channels is halved; the upsampled feature is connected in residual with the corresponding scale intermediate feature output by the encoder-decoder network, and then sequentially processed by layer normalization and ReLU activation function to obtain the first level fused and optimized feature; 6.3, second level upsampling and fusion: perform the same parameter transpose convolution upsampling on the first level output feature as in step 6.2 to expand the height and width of the feature map to 2 times the original size, and continue to halve the channel number; the upsampling feature is connected with the corresponding scale intermediate feature through residual connection, and after layer normalization and ReLU activation function processing, the second level fusion optimized feature is obtained; 6.4, third level upsampling and fusion: perform the same parameter transpose convolution upsampling on the second level output feature as in the previous two levels to further expand the height and width of the feature map to 2 times the original size, and halve the channel number synchronously; the upsampling feature is connected with the corresponding scale intermediate feature through residual connection, and after layer normalization and ReLU activation function processing, the third level fusion optimized feature is obtained; 6.5, Channel mapping and output: first through Convolution optimizes the details of the third-level fused features, and outputs a 32-channel feature map; then through Convolution maps the 32-channel features to a 3-channel RGB image format, and finally obtains a low-light enhancement image consistent with the size of the original input image.
7. A low-light image enhancement system based on multi-modal collaboration, applied to the low-light image enhancement method based on multi-modal collaboration in any one of claims 1-6, characterized in that, including: The feature extraction module receives the low-light image and the corresponding infrared image, performs convolution operation and channel attention and pixel attention cooperative enhancement through the shallow feature extraction module, and outputs low-light shallow feature and infrared shallow feature; The encoding and decoding module constructs a dual-branch encoder-decoder network based on residual double attention blocks to extract multi-scale features from low-light shallow features and infrared shallow features, and outputs encoder features and decoder features of each branch; The modal fusion module eliminates the modal feature difference through the inconsistent weight learning module, and then realizes multi-scale feature interaction and aggregation through the hierarchical cross-scale fusion module, and finally performs adaptive weighted fusion through the complementary cooperation strategy to output the weighted fusion feature; The feature enhancement module performs Mamba bidirectional state space modeling and attention enhancement on the weighted fusion feature through the state space feature module to output the enhanced fusion feature; The image reconstruction module performs step-by-step upsampling, residual fusion and channel mapping processing on the enhanced fusion feature through the reconstruction decoder to output the final low-light enhanced image.
8. A computer-readable storage medium, characterized in that, The storage medium has a computer program stored thereon, and the computer program is executed by the processor to realize all steps of the low-light image enhancement method based on multi-modal cooperation in any one of claims 1-6.
9. An electronic device, comprising: The application also discloses a low-light image enhancement method based on multi-modal cooperation.
10. The electronic device of claim 9, wherein: The application further discloses a low-light image enhancement device. An image acquisition unit acquires a low-light image and a corresponding infrared image in a low-light environment. A data processing unit performs low-light enhancement processing on the images acquired by the image acquisition unit. An image output unit receives the low-light enhanced images output by the data processing unit and displays or stores the images.