Update README.md

README.md

@@ -24,7 +24,7 @@ size_categories:
 
 ### 1.1. Overview
 
-This dataset provides a curated collection of multi-sensor, multi-temporal image patches focusing exclusively on agricultural land across China in 2021. It features Sentinel-1 (Synthetic Aperture Radar, SAR) and Sentinel-2 (Optical) imagery, standardized to a uniform pixel dimension 264*264 and a consistent Coordinate Reference System (CRS) for time-series analysis. The data acquisition is governed by a rigorous workflow designed to maximize geometric and temporal consistency across four key seasonal stages.
+This dataset provides a curated collection of multi-sensor, multi-temporal image patches focusing exclusively on agricultural land across China in 2021. The dataset contains Sentinel-1 (Synthetic Aperture Radar, SAR) and Sentinel-2 (Optical) imagery covering China where cropland pixel percentage is no less than 80%. Sentinel-2 images are in area of 2640 m * 2640 m. Pixel dimension are slightly greater than 264 * 264 dependding on their geolocation. Sentinel-1 images are standardized to a uniform pixel dimension 264*264 and a consistent Coordinate Reference System (CRS) for time-series analysis. The data acquisition is governed by a rigorous workflow designed to maximize geometric and temporal consistency across four key seasonal stages.
 
 ### 1.2. Data Sources