Remote Sensing

Remote Sensing and In-Situ Characterization of Desert Dust Outbreaks: From Sources to Climate Impact

edited by

Alejandro Rodríguez-Gómez

,

Alessia Sannino

and

Constantino Muñoz-Porcar

submission deadline 31 Dec 2026 | Viewed by 376 | Submission Open

Keywords: remote sensing; desert dust; atmospheric aerosols; climate change; sensing techniques; dust outbreak; health effects; nutrient transport; trace elements transport

(This special issue belongs to the Section Environmental Remote Sensing)

Image Formation, Super-Resolution, Deblurring, and Feature Enhancement for Satellite Remote Sensing

edited by Yesheng Gao and

Penghui Huang

submission deadline 31 Dec 2026 | 1 articles | Viewed by 373 | Submission Open

Keywords: satellite remote sensing; image super-resolution; image deblurring; feature enhancement; multi-sensor data fusion; image reconstruction; motion compensation; ground/air moving target indication; spaceborne synthetic/inverse synthetic aperture radar

(This special issue belongs to the Section Remote Sensing Image Processing)

Hydro-Geoinformatics and Advanced Remote Sensing Technologies for Sustainable Agriculture

edited by

Jisung Geba Chang

and

Jeonghwan Park

submission deadline 31 Dec 2026 | Viewed by 367 | Submission Open

Keywords: precision agriculture; sustainable agricultural management; hydro-geoinformatics and ai; phenological mapping; crop pattern analysis and crop yield prediction; soil–water–crop dynamics; soil moisture estimation; multisource data fusion (polarimetric SAR, LiDAR, multi-/hyper-spectral)

(This special issue belongs to the Section Remote Sensing in Agriculture and Vegetation)

Application of Multi-Sensor Remote Sensing to Investigate Water Energy Balance Process

edited by Linan Guo, Yanhong Wu and

Junfeng Xiong

submission deadline 31 Dec 2026 | Viewed by 351 | Submission Open

Keywords: water energy balance; thermodynamic processes; climate change; data assimilation; remote sensing in water environments; water resources

(This special issue belongs to the Section Environmental Remote Sensing)

Remote Sensing of Solar Radiation Absorbed by Land Surfaces (Second Edition)

edited by

,

,

and

submission deadline 31 Dec 2026 | Viewed by 350 | Submission Open

Keywords: land surface albedo; incoming solar radiation; aerosols, clouds, BRDF; photovoltaic; radiative forcing; validation; climate change/mitigation; earth radiation budget; applications of radiation products

(This special issue belongs to the Section Environmental Remote Sensing)

Integrated Retrieval of Atmospheric Temperature and Humidity by Hyperspectral Microwave Radiometers

edited by

Jieying He

and

Gang Ma

submission deadline 31 Dec 2026 | Viewed by 339 | Submission Open

Keywords: hyperspectral microwave radiometer; integrated retrieval; temperature and humidity profile; calibration and validation; end-to-end simulation/OSSE; data assimilation impact

(This special issue belongs to the Section Atmospheric Remote Sensing)

Deep Learning-Driven Remote Sensing Images Interpretation and Multi-Source Collaborative Detection

edited by

,

,

and

submission deadline 31 Dec 2026 | Viewed by 336 | Submission Open

Keywords: deep learning; remote sensing interpretation; multi-source data fusion; multi-source collaborative detection; object detection; land use/land cover classification; change detection; multi-sensor integration

(This special issue belongs to the Section Remote Sensing Image Processing)

Recent Advances in Multi-Platform SAR for Surface and Structural Deformation Monitoring

edited by

Seung Kuk Lee

and

Sang-Hoon Hong

submission deadline 31 Dec 2026 | Viewed by 326 | Submission Open

Keywords: InSAR (interferometric SAR); surface deformation monitoring; multi-platform SAR; Ground-based radar (GBSAR); UAV-SAR

(This special issue belongs to the Section Environmental Remote Sensing)

Advances in Mapping of Nearshore Bio-Geomorphology with Uncrewed Platforms

edited by

Evangelos Alevizos

submission deadline 31 Dec 2026 | Viewed by 326 | Submission Open

Keywords: coastal seafloor; drone; geomorphology; seafloor mapping; multi-temporal; benthic habitats; bathymetry; bedforms; biogenic reefs

High-Resolution Remote Sensing Applications in Precision Geoscience and Infrastructure Planning

edited by

Nikola Kranjčić

submission deadline 31 Dec 2026 | 1 articles | Viewed by 323 | Submission Open

Keywords: high-resolution remote sensing; precision geoscience; infrastructure planning; UAV remote sensing; LiDAR; digital elevation models; SAR and InSAR; geospatial data integration

(This special issue belongs to the Section Engineering Remote Sensing)

Multi-Source Remote Sensing Data Fusion for Crop Yield Prediction Through AI and Agro-Hydrological Advances

edited by Aparna Ravindra Phalke,

,

,

and

submission deadline 31 Dec 2026 | Viewed by 314 | Submission Open

Keywords: remote sensing; multi-source data fusion; crop monitoring; crop yield prediction; evapotranspiration (ET); irrigation mapping; agro-hydrological modeling; machine learning; computer vision; time-series analysis

(This special issue belongs to the Section Remote Sensing in Agriculture and Vegetation)

Satellite Remote Sensing of Ocean Waves and Marine Dynamics

edited by

Honglei Zheng

,

Ali Khenchaf

and Yunhua Wang

submission deadline 31 Dec 2026 | Viewed by 311 | Submission Open

Keywords: satellite remote sensing; ocean waves; marine dynamics; wave parameter retrieval; synthetic aperture radar (SAR); radar altimetry; GNSS reflectometry (GNSS-R); ocean surface monitoring

(This special issue belongs to the Section Ocean Remote Sensing)

Multi-Platform Remote Sensing for Geological Cartography and Disaster Assessment

edited by

Yun Yang

and Yuancheng Huang

submission deadline 31 Dec 2026 | Viewed by 259 | Submission Open

Keywords: multi-platform remote sensing; geological cartography; geohazards; cryospheric hazards; glacier surges; landslides; GLOFs; active tectonics; InSAR; LiDAR; UAV/drone; optical and SAR data fusion; artificial intelligence; machine learning; deep learning; small-sample learning; change detection; deformation monitoring; disaster risk assessment; early warning; climate change adaptation; sustainable development

(This special issue belongs to the Section Remote Sensing in Geology, Geomorphology and Hydrology)

Multi-Source Remote Sensing for Cryosphere Change and Its Cascading Effects

edited by Wenfeng Chen,

Francesca Baldacchino

and

Yuzhe Wang

submission deadline 31 Dec 2026 | Viewed by 250 | Submission Open

Keywords: cryosphere change; multi-source remote sensing; glacier mass balance; glacial lake; snow cover; permafrost degradation; cryospheric interactions; cascading hazards; hydrological response; multi-sensor data fusion; deep learning

(This special issue belongs to the Section Remote Sensing in Geology, Geomorphology and Hydrology)

Hyperspectral Remote Sensing for Complex Scene Understanding and Practical Applications

edited by

Degang Wang

, Lina Zhuang,

Lifeng Wang

and

Marina Ljubenovic

submission deadline 31 Dec 2026 | Viewed by 217 | Submission Open

Keywords: hyperspectral remote sensing; hyperspectral image processing; remote sensing applications; subpixel information extraction; feature extraction; classification; change detection; anomaly detection; object detection

(This special issue belongs to the Section Remote Sensing Image Processing)

Explainable and Trustworthy AI for Earth Observation Applications and Geospatial Science

edited by

Taskin Kavzoglu

and

Ismail Colkesen

submission deadline 31 Dec 2026 | Viewed by 214 | Submission Open

Keywords: explainable AI (XAI); trustworthy AI; geospatial AI (GeoAI); physics-informed AI; deep learning; interpretable deep learning

(This special issue belongs to the Section AI Remote Sensing)

Calibration in Hyperspectral Remote Sensing: Bridging Theory and Application

edited by Yaokai Liu, Qijin Han and

Shuang Wang

submission deadline 31 Dec 2026 | Viewed by 206 | Submission Open

Keywords: hyperspectral remote sensing; radiometric calibration; spectral calibration; parameter inversion; atmospheric correction; mineral exploration; vegetation biophysical parameters; data fusion; uncertainty quantification

Next-Generation GPR Imaging and AI-Powered Subsurface Geospatial Analysis

edited by

Feifei Hou

,

Jian Dong

and

Xianghuan Luo

submission deadline 31 Dec 2026 | Viewed by 191 | Submission Open

Keywords: ground-penetrating radar; GPR imaging; subsurface geospatial analysis; artificial intelligence; deep learning; subsurface target detection; non-destructive testing; infrastructure inspection; multimodal data fusion

(This special issue belongs to the Section Engineering Remote Sensing)

Spatiotemporal Deformation Monitoring with InSAR: New Advances, New Datasets, and New Applications in the NISAR Era

edited by

Jeremy Maurer

,

David Bekaert

, Rishabh Dutta and Sanaz Vajedian

submission deadline 31 Dec 2026 | Viewed by 188 | Submission Open

Keywords: InSAR; NISAR; deformation monitoring; SAR; cloud computing; InSAR applications

(This special issue belongs to the Section Remote Sensing in Geology, Geomorphology and Hydrology)

AI-Driven Multi-Source Remote Sensing Data Optimization for Atmospheric Aerosol and Cloud Quantitative Monitoring

edited by Weizhen Hou and

Qian Liu

submission deadline 31 Dec 2026 | Viewed by 187 | Submission Open

Keywords: aerosol optical depth; cloud properties; multi-source remote sensing; spatiotemporal data; machine learning; applications in climate; air quality and environment

(This special issue belongs to the Section Atmospheric Remote Sensing)

Advances in Semantic Segmentation of High-Resolution Remote Sensing

edited by

Chenbin Liang

, Yunyun Dong,

Ranyu Yin

and Zhihao Wang

submission deadline 31 Dec 2026 | Viewed by 178 | Submission Open

Keywords: high-resolution remote sensing imagery (HRRSI); semantic segmentation; robust pattern recognition; multi-modal fusion; large multi-modal models; intelligent interpretation

(This special issue belongs to the Section Remote Sensing Image Processing)

Lidar Remote Sensing of Clouds and Aerosols

edited by Haofei Wang and Guangyao Dai

submission deadline 31 Dec 2026 | Viewed by 166 | Submission Open

Keywords: lidar remote sensing; vertical structure of clouds and aerosols; cloud and aerosol interaction; stratospheric and boundary layer aerosols; active–passive sensor fusion; lidar data quality assessment; lidar design and simulation; atmospheric radiation transfer simulation

(This special issue belongs to the Section Atmospheric Remote Sensing)

Multi-Scale Remote Sensing for Environmental Situational Awareness: From Satellite to Drone

edited by

Massimiliano Lega

submission deadline 31 Dec 2026 | Viewed by 165 | Submission Open

Keywords: multi-scale remote sensing; environmental situational awareness; UAV and drone remote sensing; satellite earth observation; data fusion and sensor integration; environmental monitoring; harmful algal blooms and water quality; environmental forensic engineering; machine learning for remote sensing; operational monitoring frameworks

(This special issue belongs to the Section Environmental Remote Sensing)

Remote Sensing, Image Semantic Segmentation, and Feature Extraction

edited by

Zhen Wang

submission deadline 31 Dec 2026 | Viewed by 143 | Submission Open

Keywords: remote sensing; semantic segmentation; feature extraction; deep learning; multimodal data; domain adaptation; high-resolution imagery; earth observation; dataset; image analysis

(This special issue belongs to the Section Remote Sensing Image Processing)

Advanced Vegetation Monitoring and Dynamics by Remote Sensing Techniques

edited by

Tomáš Mikita

submission deadline 31 Dec 2026 | Viewed by 117 | Submission Open

Keywords: remote sensing; vegetation dynamics; terrestrial laser scanning (TLS); multi-sensor data fusion; forest inventory; biomass estimation; time-series analysis; ecosystem monitoring

(This special issue belongs to the Section Forest Remote Sensing)

LiDAR and Terrestrial Laser Scanning for Environmental Monitoring, Agricultural Analysis, and Environmental Infrastructure Analytics

edited by

Mostafa Arastounia

submission deadline 31 Dec 2026 | Viewed by 117 | Submission Open

Keywords: terrestrial laser scanning ; LiDAR; ecosystem and environment monitoring; agricultural analysis; change detection; forest resource assessment; tree morphology and classification; infrastructure analytics; surveying mapping and monitoring; digital twin

(This special issue belongs to the Section Environmental Remote Sensing)

Efficient Representation Learning in Hyperspectral Remote Sensing: Dimensionality Reduction Methods and Intelligent Interpretation Applications

edited by

Xiaodi Shang

,

Xudong Sun

and

Xiaopeng Wang

submission deadline 31 Dec 2026 | Viewed by 115 | Submission Open

Keywords: hyperspectral remote sensing; dimensionality reduction; representation learning; intelligent interpretation; machine learning; deep learning; image classification; target detection; band selection; feature extraction

(This special issue belongs to the Section Remote Sensing Image Processing)

Multi-Platform Remote Sensing for Bathymetric Mapping and Aquatic Monitoring

edited by

Mariusz Specht

and Oktawia Specht

submission deadline 31 Dec 2026 | Viewed by 103 | Submission Open

Keywords: bathymetric mapping; aquatic monitoring; remote sensing; earth observation; UAV; USV; LiDAR; multi-platform remote sensing; multi-source data fusion; artificial intelligence

(This special issue belongs to the Section Ocean Remote Sensing)

Monitoring and Assessment of Ecohydrological Evolution of River–Lake–Wetland Systems Based on Remote Sensing Big Data

edited by

Yanfeng Wu

and

Hsiang-te Kung

submission deadline 10 Jan 2027 | 4 articles | Viewed by 5420 | Submission Open

Keywords: remote sensing big data; ecohydrological evolution; river–lake–coastal wetland systems; ecological monitoring; hydrological assessment; machine learning; data analytics

(This special issue belongs to the Section Biogeosciences Remote Sensing)

Advanced Remote Sensing for Next-Generation Smart Agriculture: Innovations, Integration, and Applications

edited by

Fenghua Yu

,

Hao Yang

, Qiaomin Chen and

Xiaobo Sun

submission deadline 14 Jan 2027 | 5 articles | Viewed by 9181 | Submission Open

Keywords: smart agriculture; remote sensing; Unmanned Aerial Vehicles (UAVs); satellite imagery; Hyperspectral & Multispectral Imaging; LiDAR; Artificial Intelligence (AI); crop monitoring; yield prediction

(This special issue belongs to the Section Remote Sensing in Agriculture and Vegetation)

Remote Sensing Applications in Urban Environment and Climate

edited by

Jia Hu

,

Yuyu Zhou

, Ying-Bao Yang and Zhengyuan Zhu

submission deadline 15 Jan 2027 | 6 articles | Viewed by 16282 | Submission Open

Keywords: land use/cover change; urban climate; urban sustainability; urban extreme events; environmental inequality; human–environmental interactions; urban ecology; building energy use

(This special issue belongs to the Section Urban Remote Sensing)

Microwave Remote Sensing on Ocean Observation

edited by

Yanlei Du

and

Ali Khenchaf

submission deadline 15 Jan 2027 | 6 articles | Viewed by 5784 | Submission Open

Keywords: ocean dynamic parameter retrieval; detection of marine dynamic phenomena and artificial targets; advanced forward modeling of ocean scattering and emission; data fusion and reconstruction of multi-source ocean products; deep learning/artificial intelligence in ocean remote sensing; scatterometer/radiometer/SAR/GNSS-reflectometry; scale effect analysis; Polarization theory and Polarimetric SAR applications in ocean remote sensing

(This special issue belongs to the Section Ocean Remote Sensing)

GIS and RS for Spatial Documentation, Analysis and Interpretation in Multi-Scale Archaeological Applications

edited by

Jie He

,

Fulong Chen

and

Massimiliano Pepe

submission deadline 15 Jan 2027 | 3 articles | Viewed by 4598 | Submission Open

Keywords: GIS; remote sensing; archaeological space; archaeological application; multiple scales; archaeological documentation; spatial analysis; spatial interpretation and narrative

(This special issue belongs to the Section Remote Sensing for Geospatial Science)

Vision–Language Multimodal Learning for Remote Sensing and Geospatial Artificial Intelligence

edited by

,

,

,

and

submission deadline 15 Jan 2027 | 4 articles | Viewed by 2989 | Submission Open

Keywords: vision–language multimodal learning; geospatial artificial intelligence; multimodal alignment; multimodal large language models; earth observation

(This special issue belongs to the Section Remote Sensing Image Processing)

Advances in Remote Sensing of the Polar Ice with High Frequency (HF) to L-Band Radar

edited by

Shinan Lang

,

Xiangbin Cui

,

Bo Zhao

and Pedro Fidel Espín-López

submission deadline 15 Jan 2027 | 1 articles | Viewed by 2501 | Submission Open

Keywords: ice sounding radar; system design; signal processing; Antarctic; Arctic; mountain glaciers; subglacial conditions; snow cover; sea ice; satellite and aerial cryosphere

(This special issue belongs to the Section Engineering Remote Sensing)

Recent Advances in InSAR for Deformation Monitoring and Earth Surface Process Analysis

edited by

Hongyu Liang

,

Songbo Wu

and

Bochen Zhang

submission deadline 15 Jan 2027 | 6 articles | Viewed by 2272 | Submission Open

Keywords: InSAR ; deformation monitoring; earth surface processes; time-series analysis; natural hazards; geohazards; infrastructure health monitoring

(This special issue belongs to the Section Remote Sensing in Geology, Geomorphology and Hydrology)

Revolutionizing Earth Observation: Convolutional Neural Networks Innovations in Remote Sensing and Environmental Monitoring

edited by

Antonio Mazza

, Massimiliano Gargiulo,

Sergio Vitale

and

Matteo Ciotola

submission deadline 15 Jan 2027 | Viewed by 1282 | Submission Open

Keywords: artificial intelligence; deep learning; convolutional Neural Networks (CNNs); generative Adversarial Networks (GANs); earth observation; remote sensing; image processing; data fusion; super resolution

(This special issue belongs to the Section Earth Observation Data)

Deep Learning-Driven Cloud and Haze Mitigation: Advancements in Remote Sensing Image Restoration

edited by Jie Han,

Zhen Ye

and

Huifang Li

submission deadline 15 Jan 2027 | 1 articles | Viewed by 702 | Submission Open

Keywords: deep learning; dehazing; cloud removal; image restoration; multi-modal fusion; restoration quality; remote sensing

(This special issue belongs to the Section Remote Sensing Image Processing)

Urban Sprawl and Urban Sustainability: High-Resolution Remote-Sensing Image Analytics

edited by

Runyu Fan

,

Xuecao Li

and

Yan Zhang

submission deadline 15 Jan 2027 | Viewed by 513 | Submission Open

Keywords: remote sensing; deep learning; multi-sensor/ multi-modal data fusion; image classification; change detection; time-series image analysis; semantic segmentation; urban sustainability

(This special issue belongs to the Section Remote Sensing Image Processing)

Earthquake Fault Traces, Surface Deformation, and Secondary Hazards Revealed by High-Resolution Remote Sensing Data

edited by Peng Liang, Kang Li,

Wenqian Yao

and Jihong Liu

submission deadline 15 Jan 2027 | Viewed by 442 | Submission Open

Keywords: active fault; surface rupture; tectonic geomorphology; seismic hazard; machine learning; UAV; LIDAR; InSAR; high-resolution satellite imagery

(This special issue belongs to the Section Remote Sensing in Geology, Geomorphology and Hydrology)

Landslide Deformation Monitoring and Prediction with Multi-Source Remote Sensing

edited by Ryan Kromer

submission deadline 15 Jan 2027 | 1 articles | Viewed by 393 | Submission Open

Keywords: landslide deformation; multi-source remote sensing; InSAR; UAV-based sensing; data fusion; 4D deformation monitoring

(This special issue belongs to the Section Earth Observation for Emergency Management)

HF Radar Remote Sensing from Coastal to Offshore Platforms: Monitoring Marine Environments and Detecting Surface Targets

edited by

Yingwei Tian

,

Weimin Huang

, Haijian Zhang and Jiurui Zhao

submission deadline 15 Jan 2027 | Viewed by 355 | Submission Open

Keywords: HF radar; target detection and tracking; sea state inversion; data quality control and evaluation; offshore platforms; multi-source data fusion

(This special issue belongs to the Section Ocean Remote Sensing)

Observation of Optical and Radiative Properties of Atmospheric Aerosols by Ground-Based Remote Sensing Measurements

edited by

Disong Fu

, Kai Wu, Hongrong Shi and

Yu Zheng

submission deadline 20 Jan 2027 | 4 articles | Viewed by 4363 | Submission Open

Keywords: atmospheric aerosols; ground-based remote sensing; aerosol optical properties; radiative transfer modeling; lidar measurements; radiative forcing; sun photometry; long-term monitoring; data validation

(This special issue belongs to the Section Atmospheric Remote Sensing)

Machine Learning for Remote-Sensing Data Processing and Analysis

edited by Maria Kaselimi,

Olga Sykioti

,

Konstantinos Koutroumbas

and

Yongzhi Wang

submission deadline 20 Jan 2027 | 2 articles | Viewed by 2063 | Submission Open

Keywords: machine learning and deep learning for satellite, UAV and aerial-image analysis; data fusion of multispectral, hyperspectral, SAR, LiDAR and other sensors; change detection, segmentation, classification and object detection; generative AI, foundation models and self-supervised learning for remote sensing; interpretable, explainable and physics-informed machine learning; spatiotemporal modeling and prediction; AI-driven environmental monitoring and climate applications; applications in precision agriculture, urban analytics, water resources, forestry and natural-hazard assessment, including wildfires and earthquakes; machine learning for geoscience applications, including mineral and ore deposits exploration, mine-land monitoring, open-pit mine management and safety, mine recovery and geochemical pattern analysis; benchmark datasets, open-source tools and reproducibility in remote-sensing ML

(This special issue belongs to the Section Remote Sensing Image Processing)

Artificial Intelligence-Based Remote Sensing for Weather and Climate

edited by Fan Meng and Yangang Liu

submission deadline 20 Jan 2027 | 3 articles | Viewed by 1507 | Submission Open

Keywords: machine learning; deep learning; satellite meteorology; weather forecasting; climate change; tropical cyclones; data assimilation; atmospheric remote sensing; extreme weather events; physics-informed AI

(This special issue belongs to the Section Atmospheric Remote Sensing)

Multimodal Learning for Intelligent Remote Sensing Interpretation

edited by Wenkai Zhang, Yue Zhang and

Chen Wang

submission deadline 20 Jan 2027 | 1 articles | Viewed by 829 | Submission Open

Keywords: AI algorithm; VLM models; cross-modal retrieval; visual grounding; image caption; object detection and recognition; semantic segmentation; multi-modal change-detection; spatio-temporal semantic understanding

(This special issue belongs to the Section Remote Sensing Image Processing)

Foundation Models and Intelligent Agents for Remote Sensing

edited by

Xue Yang

,

Hongjie He

and

Yue Zhou

submission deadline 20 Jan 2027 | Viewed by 570 | Submission Open

Keywords: foundation models; intelligent agents; multi-modal large language models (MLLMs); remote sensing interpretation; geospatial reasoning; spatiotemporal analysis

(This special issue belongs to the Section Remote Sensing Image Processing)

Cutting-Edge Algorithms and Characteristic Geo-Applications with Remote Sensing

edited by Xuanwen Tao,

Mercedes E. Paoletti

and

Juan M. Haut

submission deadline 20 Jan 2027 | Viewed by 370 | Submission Open

Keywords: remote sensing; hyperspectral image; image classification; feature extraction; artificial intelligence; image processing

(This special issue belongs to the Section Remote Sensing Image Processing)

Robust and Trustworthy AI for SAR and Multi-Modal Remote Sensing Change Detection

edited by Muhammad Shahzad,

Mohamed Ihmeida

,

Faisal Saeed

and

Wadii Boulila

submission deadline 20 Jan 2027 | Viewed by 243 | Submission Open

Keywords: deep learning for remote sensing; multi-modal remote sensing; SAR-optical fusion; speckle-robust deep learning; SAR image change detection

(This special issue belongs to the Section AI Remote Sensing)

Integrating Artificial Intelligence and Remote Sensing for Wildfire Detection, Monitoring and Management

edited by

Arnick Abdollahi

submission deadline 25 Jan 2027 | 2 articles | Viewed by 5758 | Submission Open

Keywords: artificial intelligence; wildfire; bushfire risk modelling and reduction; earth and space science informatics; environmental assessment and monitoring; photogrammetry and remote sensing; natural hazards; image processing; machine learning

(This special issue belongs to the Section Environmental Remote Sensing)

Journal Menu

Journal Browser

Special Issues

Further Information

Guidelines

MDPI Initiatives

Follow MDPI