The principle of ptychography is applied in known plain text attack on the double random phase encoding （DRPE） system. We find that with several pairs of plain texts and cipher texts, the model of attack on DRPE can...The principle of ptychography is applied in known plain text attack on the double random phase encoding （DRPE） system. We find that with several pairs of plain texts and cipher texts, the model of attack on DRPE can be converted to the model of ptyehographical imaging. Owing to the inherent merits of the ptyehographical imaging, the DRPE system can be breached totally in a fast and nearly perfect way, which is unavailable for currently existing attack methods. Further, since the decryption keys can be seen as an object to be imaged from the perspective of imaging, the ptychographical technique may be a kind of new direction to further analysis of the security of other encryption systems based on double random keys.展开更多
Full-color imaging is essential in digital pathology for accurate tissue analysis.Utilizing advanced optical modulation and phase retrieval algorithms,Fourier ptychographic microscopy(FPM)offers a powerful solution fo...Full-color imaging is essential in digital pathology for accurate tissue analysis.Utilizing advanced optical modulation and phase retrieval algorithms,Fourier ptychographic microscopy(FPM)offers a powerful solution for high-throughput digital pathology,combining high resolution,large field of view,and extended depth of field(DOF).However,the full-color capabilities of FPM are hindered by coherent color artifacts and reduced computational efficiency,which significantly limits its practical applications.Color-transferbased FPM(CFPM)has emerged as a potential solution,theoretically reducing both acquisition and reconstruction threefold time.Yet,existing methods fall short of achieving the desired reconstruction speed and colorization quality.In this study,we report a generalized dual-color-space constrained model for FPM colorization.This model provides a mathematical framework for model-based FPM colorization,enabling a closed-form solution without the need for redundant iterative calculations.Our approach,termed generalized CFPM(gCFPM),achieves colorization within seconds for megapixel-scale images,delivering superior colorization quality in terms of both colorfulness and sharpness,along with an extended DOF.Both simulations and experiments demonstrate that gCFPM surpasses state-of-the-art methods across all evaluated criteria.Our work offers a robust and comprehensive workflow for high-throughput full-color pathological imaging using FPM platforms,laying a solid foundation for future advancements in methodology and engineering.展开更多
Fourier ptychographic microscopy(FPM)is an innovative computational microscopy approach that enables high-throughput imaging with high resolution,wide field of view,and quantitative phase imaging(QPI)by simultaneously...Fourier ptychographic microscopy(FPM)is an innovative computational microscopy approach that enables high-throughput imaging with high resolution,wide field of view,and quantitative phase imaging(QPI)by simultaneously capturing bright-field and dark-field images.However,effectively utilizing dark-field intensity images,including both normally exposed and overexposed data,which contain valuable high-angle illumination information,remains a complex challenge.Successfully extracting and applying this information could significantly enhance phase reconstruction,benefiting processes such as virtual staining and QPI imaging.To address this,we introduce a multi-exposure image fusion(MEIF)framework that optimizes dark-field information by incorporating it into the FPM preprocessing workflow.MEIF increases the data available for reconstruction without requiring changes to the optical setup.We evaluate the framework using both feature-domain and traditional FPM,demonstrating that it achieves substantial improvements in intensity resolution and phase information for biological samples that exceed the performance of conventional high dynamic range(HDR)methods.This image preprocessing-based information-maximization strategy fully leverages existing datasets and offers promising potential to drive advancements in fields such as microscopy,remote sensing,and crystallography.展开更多
Two mainstream approaches for solving inverse sample reconstruction problems in programmable illumination computational microscopy rely on either deep models or physical models.Solutions based on physical models posse...Two mainstream approaches for solving inverse sample reconstruction problems in programmable illumination computational microscopy rely on either deep models or physical models.Solutions based on physical models possess strong generalization capabilities while struggling with global optimization of inverse problems due to a lack of sufficient physical constraints.In contrast,deep-learning methods have strong problem-solving abilities,but their generalization ability is often questioned because of the unclear physical principles.In addition,conventional deep models are difficult to apply to some specific scenes because of the difficulty in acquiring high-quality training data and their limited capacity to generalize across different scenarios.To combine the advantages of deep models and physical models together,we propose a hybrid framework consisting of three subneural networks(two deep-learning networks and one physics-based network).We first obtain a result with rich semantic information through a light deeplearning neural network and then use it as the initial value of the physical network to make its output comply with physical process constraints.These two results are then used as the input of a fusion deeplearning neural work that utilizes the paired features between the reconstruction results of two different models to further enhance imaging quality.The proposed hybrid framework integrates the advantages of both deep models and physical models and can quickly solve the computational reconstruction inverse problem in programmable illumination computational microscopy and achieve better results.We verified the feasibility and effectiveness of the proposed hybrid framework with theoretical analysis and actual experiments on resolution targets and biological samples.展开更多
Fourier ptychographic microscopy(FPM)is a newly developed imaging technique which stands out by virtue of its high-resolution and wide FOV.It improves a microscope's imaging perfor-mance beyond the diffraction lim...Fourier ptychographic microscopy(FPM)is a newly developed imaging technique which stands out by virtue of its high-resolution and wide FOV.It improves a microscope's imaging perfor-mance beyond the diffraction limit of the employed optical components by illuminating the sample with oblique waves of different incident angles,similar to the concept of synthetic aperture.We propose to use an objective lens with high-NA to generate oblique illuminating waves in FPM.We demonstrate utilizing an objective lens with higher NA to iluminate the sample leads to better resolution by simulations,in which a resolution of 0.28 pum is achieved by using a high-NA illuminating objective lens(NA=1.49)and a low-NA collecting objective lens(NA=0.2)in coherent imaging(λ=488 nm).We then deeply study FPM's exact relevance of convergence speed to spatial spectrum overlap in frequency domain.The simulation results show that an overlap of about 60%is the optimal choice to acquire a high-quality recovery(520*520 pixels)with about 2 min's computing time.In addition,we testify the robustness of the algorithm of FPM to additive noises and its suitability for phase objects,which further proves FPM's potential application in biomedical imaging.展开更多
Fourier ptychographic microscopy(FPM)is a promising technique for achieving high-resolution and large fieldof-view imaging,which is particularly suitable for pathological applications,such as imaging hematoxylin and e...Fourier ptychographic microscopy(FPM)is a promising technique for achieving high-resolution and large fieldof-view imaging,which is particularly suitable for pathological applications,such as imaging hematoxylin and eosin(H&E)stained tissues with high space-bandwidth and reduced artifacts.However,current FPM implementations require either precise system calibration and high-quality raw data,or significant computational loads due to iterative algorithms,which limits the practicality of FPM in routine pathological examinations.In this work,latent wavefront denoting the unobservable exiting wave at the surface of the sensor is introduced.A latent wavefront physical model optimized with variational expectation maximization(VEM)is proposed to tackle the inverse problem of FPM.The VEM-FPM alternates between solving a non-convex optimization problem as the main task for the latent wavefront in the spatial domain and merging together their Fourier spectrum in the Fourier plane as an intermediate product by solving a convex closed-formed Fourier space optimization.The VEM-FPM approach enables a stitching-free,full-field reconstruction for Fourier ptychography over a 5.3 mm×5.3 mm field of view,using a 2.5×objective with a numerical aperture(NA)of 0.08.The synthetic aperture achieves a resolution equivalent to 0.53 NA at 532 nm wavelength.The execution speed of VEM-FPM is twice as fast as that of state-of-the-art feature-domain methods while maintaining comparable reconstruction quality.展开更多
Diffraction intensities of the 3D ptychographic iterative engine(3PIE)were written as a set of linear equations of the selfcorrelations of Fourier components of all sample slices,and an effective computing method was ...Diffraction intensities of the 3D ptychographic iterative engine(3PIE)were written as a set of linear equations of the selfcorrelations of Fourier components of all sample slices,and an effective computing method was developed to solve these linear equations for the transmission functions of all sample slices analytically.With both theoretical analysis and numerical simulations,this study revealed the underlying physics and mathematics of 3PIE and demonstrated for the first time,to our knowledge,that 3PIE can generate mathematically unique reconstruction even with noisy data.展开更多
The properties of a series of phase measurement techniques,including interferometry,the Hartmann–Shack wavefront sensor,the knife-edge technique,and coherent diffraction imaging,are summarized and their performance i...The properties of a series of phase measurement techniques,including interferometry,the Hartmann–Shack wavefront sensor,the knife-edge technique,and coherent diffraction imaging,are summarized and their performance in high power laser applications is compared.The advantages,disadvantages,and application ranges of each technique are discussed.展开更多
Quantitative phase imaging(QPI)has emerged as a valuable tool for biomedical research thanks to its unique capabilities for quantifying optical thickness variation of living cells and tissues.Among many QPI methods,Fo...Quantitative phase imaging(QPI)has emerged as a valuable tool for biomedical research thanks to its unique capabilities for quantifying optical thickness variation of living cells and tissues.Among many QPI methods,Fourier ptychographic microscopy(FPM)allows long-term label-free observation and quantitative analysis of large cell populations without compromising spatial and temporal resolution.However,high spatio-temporal resolution imaging over a long-time scale(from hours to days)remains a critical challenge:optically inhomogeneous structure of biological specimens as well as mechanical perturbations and thermal fluctuations of the microscope body all result in time-varying aberration and focus drifts,significantly degrading the imaging performance for long-term study.Moreover,the aberrations are sample-and environmentdependent,and cannot be compensated by a fixed optical design,thus necessitating rapid dynamic correction in the imaging process.Here,we report an adaptive optical QPI method based on annular illumination FPM.In this method,the annular matched illumination configuration(i.e.,the illumination numerical aperture(NA)strictly equals to the objective NA),which is the key for recovering low-frequency phase information,is further utilized for the accurate imaging aberration characterization.By using only 6 low-resolution images captured with 6 different illumination angles matching the NA of a 10x,0.4 NA objective,we recover high-resolution quantitative phase images(synthetic NA of 0.8)and characterize the aberrations in real time,restoring the optimum resolution of the system adaptively.Applying our method to live-cell imaging,we achieve diffraction-limited performance(full-pitch resolution of 655 nm at a wavelength of 525 nm)across a wide field of view(1.77mm2)over an extended period of time.展开更多
X-ray ptychographic tomography is a nondestructive method for three dimensional(3D)imaging with nanometer-sized resolvable features.The size of the volume that can be imaged is almost arbitrary,limited only by the pen...X-ray ptychographic tomography is a nondestructive method for three dimensional(3D)imaging with nanometer-sized resolvable features.The size of the volume that can be imaged is almost arbitrary,limited only by the penetration depth and the available scanning time.Here we present a method that rapidly accelerates the imaging operation over a given volume through acquiring a limited set of data via large angular reduction and compensating for the resulting ill-posedness through deeply learned priors.The proposed 3D reconstruction method“RAPID”relies initially on a subset of the object measured with the nominal number of required illumination angles and treats the reconstructions from the conventional two-step approach as ground truth.It is then trained to reproduce equal fidelity from much fewer angles.After training,it performs with similar fidelity on the hitherto unexamined portions of the object,previously not shown during training,with a limited set of acquisitions.In our experimental demonstration,the nominal number of angles was 349 and the reduced number of angles was 21,resulting in a×140 aggregate speedup over a volume of 4.48×93.18×3.92μm^(3) and with(14 nm)^(3) feature size,i.e.-10^(8) voxels.RAPID’s key distinguishing feature over earlier attempts is the incorporation of atrous spatial pyramid pooling modules into the deep neural network framework in an anisotropic way.We found that adjusting the atrous rate improves reconstruction fidelity because it expands the convolutional kernels’range to match the physics of multi-slice ptychography without significantly increasing the number of parameters.展开更多
The usage of full-color imaging in digital pathology produces significant results.Compared with a grayscale image or a pseudocolor image containing contrast information,a full-color image can identify and detect the t...The usage of full-color imaging in digital pathology produces significant results.Compared with a grayscale image or a pseudocolor image containing contrast information,a full-color image can identify and detect the target object better with color texture information.Fourier ptychographic microscopy(FPM)is a high-throughput computational imaging technique that breaks the tradeoff between high resolution(HR)and a large field of view.It also eliminates the artifacts of scanning and stitching in digital pathology and improves its imaging efficiency.However,the conventional full-color digital pathology based on FPM is still time-consuming because of the repeated experiments with tri-wavelengths.A color transfer FPM approach termed“CFPM”was reported.The color texture information of a low-resolution full-color pathologic image is directly transferred to the HR grayscale FPM image captured by only a single wavelength.Both of the color space of FPM based on the standard CIE-XYZ color model and the display based on the standard RGB color space were established.Different FPM colorization schemes were analyzed and compared with 30 biological samples.Three types of evaluation approaches were provided,including the root-mean-square error(RMSE),the difference maps,and the image histogram cosine similarity.The average RMSE values of the conventional method and CFPM compared with the ground truth were 5.3%and 5.7%,respectively.Therefore,the reconstruction time is significantly reduced by 2/3 with the sacrifice of precision of only 0.4%.The CFPM method is also compatible with advanced fast FPM approaches to further reduce computation time.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 61575197 and 61307018the K.C.Wong Education Foundation,the President Fund of University of Chinese Academy of Sciencesthe Fusion Funds of Research and Education of Chinese Academy of Sciences
文摘The principle of ptychography is applied in known plain text attack on the double random phase encoding （DRPE） system. We find that with several pairs of plain texts and cipher texts, the model of attack on DRPE can be converted to the model of ptyehographical imaging. Owing to the inherent merits of the ptyehographical imaging, the DRPE system can be breached totally in a fast and nearly perfect way, which is unavailable for currently existing attack methods. Further, since the decryption keys can be seen as an object to be imaged from the perspective of imaging, the ptychographical technique may be a kind of new direction to further analysis of the security of other encryption systems based on double random keys.
基金supported by the National Natural Science Foundation of China(Grant Nos.12104500 and 82430062)the Key Research and Development Projects of Shaanxi Province(Grant No.2023-YBSF-263),the Shenzhen Engineering Research Centre(Grant No.XMHT20230115004)the Shenzhen Science and Technology Innovation Commission(Grant No.KCXFZ20201221173207022).
文摘Full-color imaging is essential in digital pathology for accurate tissue analysis.Utilizing advanced optical modulation and phase retrieval algorithms,Fourier ptychographic microscopy(FPM)offers a powerful solution for high-throughput digital pathology,combining high resolution,large field of view,and extended depth of field(DOF).However,the full-color capabilities of FPM are hindered by coherent color artifacts and reduced computational efficiency,which significantly limits its practical applications.Color-transferbased FPM(CFPM)has emerged as a potential solution,theoretically reducing both acquisition and reconstruction threefold time.Yet,existing methods fall short of achieving the desired reconstruction speed and colorization quality.In this study,we report a generalized dual-color-space constrained model for FPM colorization.This model provides a mathematical framework for model-based FPM colorization,enabling a closed-form solution without the need for redundant iterative calculations.Our approach,termed generalized CFPM(gCFPM),achieves colorization within seconds for megapixel-scale images,delivering superior colorization quality in terms of both colorfulness and sharpness,along with an extended DOF.Both simulations and experiments demonstrate that gCFPM surpasses state-of-the-art methods across all evaluated criteria.Our work offers a robust and comprehensive workflow for high-throughput full-color pathological imaging using FPM platforms,laying a solid foundation for future advancements in methodology and engineering.
基金supported by the National Natural Science Foundation of China(Grant No.12104500)the Key Research and Development Projects of Shaanxi Province of China(Grant No.2023-YBSF-263).
文摘Fourier ptychographic microscopy(FPM)is an innovative computational microscopy approach that enables high-throughput imaging with high resolution,wide field of view,and quantitative phase imaging(QPI)by simultaneously capturing bright-field and dark-field images.However,effectively utilizing dark-field intensity images,including both normally exposed and overexposed data,which contain valuable high-angle illumination information,remains a complex challenge.Successfully extracting and applying this information could significantly enhance phase reconstruction,benefiting processes such as virtual staining and QPI imaging.To address this,we introduce a multi-exposure image fusion(MEIF)framework that optimizes dark-field information by incorporating it into the FPM preprocessing workflow.MEIF increases the data available for reconstruction without requiring changes to the optical setup.We evaluate the framework using both feature-domain and traditional FPM,demonstrating that it achieves substantial improvements in intensity resolution and phase information for biological samples that exceed the performance of conventional high dynamic range(HDR)methods.This image preprocessing-based information-maximization strategy fully leverages existing datasets and offers promising potential to drive advancements in fields such as microscopy,remote sensing,and crystallography.
基金supported by the National Natural Science Foundation of China(Grant No.62275020).
文摘Two mainstream approaches for solving inverse sample reconstruction problems in programmable illumination computational microscopy rely on either deep models or physical models.Solutions based on physical models possess strong generalization capabilities while struggling with global optimization of inverse problems due to a lack of sufficient physical constraints.In contrast,deep-learning methods have strong problem-solving abilities,but their generalization ability is often questioned because of the unclear physical principles.In addition,conventional deep models are difficult to apply to some specific scenes because of the difficulty in acquiring high-quality training data and their limited capacity to generalize across different scenarios.To combine the advantages of deep models and physical models together,we propose a hybrid framework consisting of three subneural networks(two deep-learning networks and one physics-based network).We first obtain a result with rich semantic information through a light deeplearning neural network and then use it as the initial value of the physical network to make its output comply with physical process constraints.These two results are then used as the input of a fusion deeplearning neural work that utilizes the paired features between the reconstruction results of two different models to further enhance imaging quality.The proposed hybrid framework integrates the advantages of both deep models and physical models and can quickly solve the computational reconstruction inverse problem in programmable illumination computational microscopy and achieve better results.We verified the feasibility and effectiveness of the proposed hybrid framework with theoretical analysis and actual experiments on resolution targets and biological samples.
基金the National Basic Research Program of China(973 Program)(No.2015CB352003)the National Natural Science Foundation of China(No.61335003,61377013,61378051 and 61427818)+1 种基金NSFC of Zhejiang province LR16F050001,Innovation Joint Research Center for iCPS(2015XZZX005-01)Open Foundation of the State Key Laboratory of Modern Optical Instrumentation.
文摘Fourier ptychographic microscopy(FPM)is a newly developed imaging technique which stands out by virtue of its high-resolution and wide FOV.It improves a microscope's imaging perfor-mance beyond the diffraction limit of the employed optical components by illuminating the sample with oblique waves of different incident angles,similar to the concept of synthetic aperture.We propose to use an objective lens with high-NA to generate oblique illuminating waves in FPM.We demonstrate utilizing an objective lens with higher NA to iluminate the sample leads to better resolution by simulations,in which a resolution of 0.28 pum is achieved by using a high-NA illuminating objective lens(NA=1.49)and a low-NA collecting objective lens(NA=0.2)in coherent imaging(λ=488 nm).We then deeply study FPM's exact relevance of convergence speed to spatial spectrum overlap in frequency domain.The simulation results show that an overlap of about 60%is the optimal choice to acquire a high-quality recovery(520*520 pixels)with about 2 min's computing time.In addition,we testify the robustness of the algorithm of FPM to additive noises and its suitability for phase objects,which further proves FPM's potential application in biomedical imaging.
基金National Natural Science Foundation of China(62235009)。
文摘Fourier ptychographic microscopy(FPM)is a promising technique for achieving high-resolution and large fieldof-view imaging,which is particularly suitable for pathological applications,such as imaging hematoxylin and eosin(H&E)stained tissues with high space-bandwidth and reduced artifacts.However,current FPM implementations require either precise system calibration and high-quality raw data,or significant computational loads due to iterative algorithms,which limits the practicality of FPM in routine pathological examinations.In this work,latent wavefront denoting the unobservable exiting wave at the surface of the sensor is introduced.A latent wavefront physical model optimized with variational expectation maximization(VEM)is proposed to tackle the inverse problem of FPM.The VEM-FPM alternates between solving a non-convex optimization problem as the main task for the latent wavefront in the spatial domain and merging together their Fourier spectrum in the Fourier plane as an intermediate product by solving a convex closed-formed Fourier space optimization.The VEM-FPM approach enables a stitching-free,full-field reconstruction for Fourier ptychography over a 5.3 mm×5.3 mm field of view,using a 2.5×objective with a numerical aperture(NA)of 0.08.The synthetic aperture achieves a resolution equivalent to 0.53 NA at 532 nm wavelength.The execution speed of VEM-FPM is twice as fast as that of state-of-the-art feature-domain methods while maintaining comparable reconstruction quality.
基金This work was supported by the National Natural Science Foundation of China(No.61827816).
文摘Diffraction intensities of the 3D ptychographic iterative engine(3PIE)were written as a set of linear equations of the selfcorrelations of Fourier components of all sample slices,and an effective computing method was developed to solve these linear equations for the transmission functions of all sample slices analytically.With both theoretical analysis and numerical simulations,this study revealed the underlying physics and mathematics of 3PIE and demonstrated for the first time,to our knowledge,that 3PIE can generate mathematically unique reconstruction even with noisy data.
基金supported by the One Hundred Talents Project of the Chinese Academy of Sciences,China (Grant No.1204341-XR0)
文摘The properties of a series of phase measurement techniques,including interferometry,the Hartmann–Shack wavefront sensor,the knife-edge technique,and coherent diffraction imaging,are summarized and their performance in high power laser applications is compared.The advantages,disadvantages,and application ranges of each technique are discussed.
基金supported by the National Natural Science Foundation of China(61905115,62105151,62175109,U21B2033,62105156)Leading Technology of Jiangsu Basic Research Plan(BK20192003),Youth Foundation of Jiangsu Province(BK20190445,BK20210338)+1 种基金Fundamental Research Funds for the Central Universities(30920032101)Open Research Fund of Jiangsu Key Laboratory of Spectral Imaging&Intelligent Sense(JSGP202105,JSGP202201).
文摘Quantitative phase imaging(QPI)has emerged as a valuable tool for biomedical research thanks to its unique capabilities for quantifying optical thickness variation of living cells and tissues.Among many QPI methods,Fourier ptychographic microscopy(FPM)allows long-term label-free observation and quantitative analysis of large cell populations without compromising spatial and temporal resolution.However,high spatio-temporal resolution imaging over a long-time scale(from hours to days)remains a critical challenge:optically inhomogeneous structure of biological specimens as well as mechanical perturbations and thermal fluctuations of the microscope body all result in time-varying aberration and focus drifts,significantly degrading the imaging performance for long-term study.Moreover,the aberrations are sample-and environmentdependent,and cannot be compensated by a fixed optical design,thus necessitating rapid dynamic correction in the imaging process.Here,we report an adaptive optical QPI method based on annular illumination FPM.In this method,the annular matched illumination configuration(i.e.,the illumination numerical aperture(NA)strictly equals to the objective NA),which is the key for recovering low-frequency phase information,is further utilized for the accurate imaging aberration characterization.By using only 6 low-resolution images captured with 6 different illumination angles matching the NA of a 10x,0.4 NA objective,we recover high-resolution quantitative phase images(synthetic NA of 0.8)and characterize the aberrations in real time,restoring the optimum resolution of the system adaptively.Applying our method to live-cell imaging,we achieve diffraction-limited performance(full-pitch resolution of 655 nm at a wavelength of 525 nm)across a wide field of view(1.77mm2)over an extended period of time.
基金funded by the Intelligence Advanced Research Projects Activity,Office of the Director of National Intelligence(IARPA-ODNI)under contract FA8650-17-C-9113.
文摘X-ray ptychographic tomography is a nondestructive method for three dimensional(3D)imaging with nanometer-sized resolvable features.The size of the volume that can be imaged is almost arbitrary,limited only by the penetration depth and the available scanning time.Here we present a method that rapidly accelerates the imaging operation over a given volume through acquiring a limited set of data via large angular reduction and compensating for the resulting ill-posedness through deeply learned priors.The proposed 3D reconstruction method“RAPID”relies initially on a subset of the object measured with the nominal number of required illumination angles and treats the reconstructions from the conventional two-step approach as ground truth.It is then trained to reproduce equal fidelity from much fewer angles.After training,it performs with similar fidelity on the hitherto unexamined portions of the object,previously not shown during training,with a limited set of acquisitions.In our experimental demonstration,the nominal number of angles was 349 and the reduced number of angles was 21,resulting in a×140 aggregate speedup over a volume of 4.48×93.18×3.92μm^(3) and with(14 nm)^(3) feature size,i.e.-10^(8) voxels.RAPID’s key distinguishing feature over earlier attempts is the incorporation of atrous spatial pyramid pooling modules into the deep neural network framework in an anisotropic way.We found that adjusting the atrous rate improves reconstruction fidelity because it expands the convolutional kernels’range to match the physics of multi-slice ptychography without significantly increasing the number of parameters.
基金This work was supported by the National Natural Science Foundation of China(Grant No.81427802).
文摘The usage of full-color imaging in digital pathology produces significant results.Compared with a grayscale image or a pseudocolor image containing contrast information,a full-color image can identify and detect the target object better with color texture information.Fourier ptychographic microscopy(FPM)is a high-throughput computational imaging technique that breaks the tradeoff between high resolution(HR)and a large field of view.It also eliminates the artifacts of scanning and stitching in digital pathology and improves its imaging efficiency.However,the conventional full-color digital pathology based on FPM is still time-consuming because of the repeated experiments with tri-wavelengths.A color transfer FPM approach termed“CFPM”was reported.The color texture information of a low-resolution full-color pathologic image is directly transferred to the HR grayscale FPM image captured by only a single wavelength.Both of the color space of FPM based on the standard CIE-XYZ color model and the display based on the standard RGB color space were established.Different FPM colorization schemes were analyzed and compared with 30 biological samples.Three types of evaluation approaches were provided,including the root-mean-square error(RMSE),the difference maps,and the image histogram cosine similarity.The average RMSE values of the conventional method and CFPM compared with the ground truth were 5.3%and 5.7%,respectively.Therefore,the reconstruction time is significantly reduced by 2/3 with the sacrifice of precision of only 0.4%.The CFPM method is also compatible with advanced fast FPM approaches to further reduce computation time.
