I have a satellite image of 7-channels (Basically I have seven .tif files, one for each band). And I have a .csv file with coordinates of points-of-interest that are in the region shot by the satellite. I want to cut small portions of the image in the surroundings of each coordinate point. How could I do that?
As I don't have a full working code right now, it really doesn't matter the size of those small portions of image. For the explanation of this question let's say that I want them to be 15x15 pixels. So for the moment, my final objective is to obtain a lot of 15x15x7 vectors, one for every coordinate point that I have in the .csv file. And that is what I am stucked with. (the "7" in the "15x15x7" is because the image has 7 channels)
Just to give some background in case it's relevant: I will use those vectors later to train a CNN model in keras.
This is what I did so far: (I am using jupyter notebook, anaconda environment)
imported gdal, numpy, matplotlib, geopandas, among other libraries.
Opened the .gif files using gdal, converted them into arrays
Opened the .csv file using pandas.
Created a numpy array called "imagen" of shape (7931, 7901, 3) that will host the 7 bands of the satellite image (in form of numbers). At this point I just need to know which rows and colums of the array "imagen" correspond to each coordinate point. In other words I need to convert every coordinate point into a pair of numbers (row,colum). And that is what I am stucked with.
After that, I think that the "cutting part" will be easy.
#I import libraries
from osgeo import gdal_array
import numpy as np
import matplotlib.pyplot as plt
import pandas as pd
import geopandas
from geopandas import GeoDataFrame
from shapely.geometry import Point
#I access the satellite images (I just show one here to make it short)
b1 = r"E:\Imágenes Satelitales\2017\226_86\1\LC08_L1TP_226086_20170116_20170311_01_T1_sr_band1.tif"
band1 = gdal.Open(b1, gdal.GA_ReadOnly)
#I open the .csv file
file_svc = "C:\\Users\\Administrador\Desktop\DeepLearningInternship\Crop Yield Prediction\Crop Type Classification model - CNN\First\T28_Pringles4.csv"
df = pd.read_csv(file_svc)
print(df.head())
That prints something like this:
Lat1 Long1 CropingState
-37.75737 -61.14537 Barbecho
-37.78152 -61.15872 Verdeo invierno
-37.78248 -61.17755 Barbecho
-37.78018 -61.17357 Campo natural
-37.78850 -61.18501 Campo natural
#I create the array "imagen" (I only show one channel here to make it short)
imagen = (np.zeros(7931*7901*7, dtype = np.float32)).reshape(7931,7901,7)
imagen[:,:,0] = band1.ReadAsArray().astype(np.float32)
#And then I can plot it:
plt.imshow(imagen[:,:,0], cmap = 'hot')
plt.plot()
Which plots something like this:
I want to transform those (-37,-61) into something like (2230,1750). But I haven't figured it how yet. Any clues?