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从ESA Sentinel-2产品加载python中的rgb图像并使用opencv保存

sentinel2 snap-python opencv python

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Ioannis Nasios · 技术社区 · 8 年前

从ESA快照来看,对于RGB图像,我们应该将波段4放入红色通道,将波段3放入绿色通道,将波段2放入蓝色通道。我们怎么能把这些带着巨蟒的带子 numpy 数组,这样我们就可以做我们想要的任何图像处理,然后在磁盘上保存一个RGB图像?

from snappy import Product
from snappy import ProductIO
import numpy as np
import cv2

product = ProductIO.readProduct(path_to_product)

width = product.getSceneRasterWidth()
height = product.getSceneRasterHeight()

# Natural colors 
red = product.getBand('B4')
green = product.getBand('B3')
blue = product.getBand('B2')

例如,以下是上述变量之一的类型(其他变量相同):

type(red)
# org.esa.snap.core.datamodel.Band

如何从这些数据中获取numpy数组,然后将它们保存到磁盘上作为JPG图像?

1 回复 | 直到 8 年前

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desertnaut SKZI 8 年前

#Read in channel's pixels    
red_pixels = np.zeros(width * height, np.float32)
red.readPixels(0, 0, width, height, red_pixels)

green_pixels = np.zeros(width * height, np.float32)
green.readPixels(0, 0, width, height, green_pixels)

blue_pixels = np.zeros(width * height, np.float32)
blue.readPixels(0, 0, width, height, blue_pixels)

#Reshape to image dimensions
red_pixels.shape =  height, width
green_pixels.shape =  height, width
blue_pixels.shape =  height, width

#Combine into a RGB image
rgb=np.zeros((height,width,3))
rgb[...,0] = red_pixels
rgb[...,1] = green_pixels
rgb[...,2] = blue_pixels

numpy

rgb2 = ((np.clip(rgb.copy(),0,1))*255).astype('uint8')
#Reverse Red-Blue Channels as open cv will reverse again upon writing image on disk
cv2.imwrite('image_name.jpg',rgb2[...,::-1])