ee.Image.arrayMask

יוצרת תמונה של מערך שבו כל פיקסל עם ערך מערך מוסתר על ידי פיקסל אחר עם ערך מערך, ומשאירה רק את הרכיבים שבהם המסכה שונה מאפס. אם לתמונת המסכה יש פס אחד, היא תוחל על כל הפסים של 'input'. אחרת, מספר הפסים שלהן צריך להיות זהה.

שימושהחזרות
Image.arrayMask(mask)תמונה
ארגומנטסוגפרטים
זה: inputתמונהמערך תמונות למסכה.
maskתמונהמערך של תמונות להוספת מסכה.

דוגמאות

עורך הקוד (JavaScript)

// A function to print arrays for a selected pixel in the following examples.
function sampArrImg(arrImg) {
  var point = ee.Geometry.Point([-121, 42]);
  return arrImg.sample(point, 500).first().get('array');
}

// Create a 1D array image with length 6.
var arrayImg1D = ee.Image([0, 1, 2, 4, 0, 5]).toArray();
print('1D array image (pixel)', sampArrImg(arrayImg1D));
// [0, 1, 2, 4, 0, 5]

// Create a mask using a relational operator to mask values greater than 2.
var mask1D = arrayImg1D.lte(2);
print('1D mask for greater than value 2 (pixel)', sampArrImg(mask1D));
// [1, 1, 1, 0, 1, 0]

var arrayImg1DMask = arrayImg1D.arrayMask(mask1D);
print('1D array image mask (pixel)', sampArrImg(arrayImg1DMask));
// [0, 1, 2, 0]

// Self mask the 1D array image. Value zero will be masked out.
var arrayImg1DselfMask = arrayImg1D.arrayMask(arrayImg1D);
print('1D array image self mask (pixel)', sampArrImg(arrayImg1DselfMask));
// [1, 2, 4, 5]

// Create a 2D array image.
var arrayImg2D = arrayImg1D.arrayReshape(ee.Image([2, 3]).toArray(), 2);
print('2D 2x3 array image (pixel)', sampArrImg(arrayImg2D));
// [[0, 1, 2],
//  [4, 0, 5]]

// Slice out a row to use as a column mask.
var rowAsMaskForCols = arrayImg2D.arraySlice(0, 1, 2);
print('2D mask for cols (pixel)', sampArrImg(rowAsMaskForCols));
// [[4, 0, 5]]

var arrayImg2DMaskCols = arrayImg2D.arrayMask(rowAsMaskForCols);
print('2D array image cols masked (pixel)', sampArrImg(arrayImg2DMaskCols));
// [[0, 2],
//  [4, 5]]

// Slice out a column to use as a row mask.
var colAsMaskForRows = arrayImg2D.arraySlice(1, 1, 2);
print('2D mask for rows (pixel)', sampArrImg(colAsMaskForRows));
// [[1],
//  [0]]

var arrayImg2DMaskRows = arrayImg2D.arrayMask(colAsMaskForRows);
print('2D array image rows masked (pixel)', sampArrImg(arrayImg2DMaskRows));
// [[0, 1, 2]]

הגדרת Python

מידע על Python API ועל שימוש ב-geemap לפיתוח אינטראקטיבי מופיע בדף Python Environment.

import ee
import geemap.core as geemap

Colab (Python)

# A function to print arrays for a selected pixel in the following examples.
def samp_arr_img(arr_img):
  point = ee.Geometry.Point([-121, 42])
  return arr_img.sample(point, 500).first().get('array')

# Create a 1D array image with length 6.
array_img_1d = ee.Image([0, 1, 2, 4, 0, 5]).toArray()
print('1D array image (pixel):', samp_arr_img(array_img_1d).getInfo())
# [0, 1, 2, 4, 0, 5]

# Create a mask using a relational operator to mask values greater than 2.
mask_1d = array_img_1d.lte(2)
print(
    '1D mask for greater than value 2 (pixel):',
    samp_arr_img(mask_1d).getInfo()
)
# [1, 1, 1, 0, 1, 0]

array_img1d_mask = array_img_1d.arrayMask(mask_1d)
print('1D array image mask (pixel):', samp_arr_img(array_img1d_mask).getInfo())
# [0, 1, 2, 0]

# Self mask the 1D array image. Value zero will be masked out.
array_img_1d_self_mask = array_img_1d.arrayMask(array_img_1d)
print(
    '1D array image self mask (pixel):',
    samp_arr_img(array_img_1d_self_mask).getInfo()
)
# [1, 2, 4, 5]

# Create a 2D array image.
array_img_2d = array_img_1d.arrayReshape(ee.Image([2, 3]).toArray(), 2)
print('2D 2x3 array image (pixel):', samp_arr_img(array_img_2d).getInfo())
# [[0, 1, 2],
#  [4, 0, 5]]

# Slice out a row to use as a column mask.
row_as_mask_for_cols = array_img_2d.arraySlice(0, 1, 2)
print('2D mask for cols (pixel):', samp_arr_img(row_as_mask_for_cols).getInfo())
# [[4, 0, 5]]

array_img_2d_mask_cols = array_img_2d.arrayMask(row_as_mask_for_cols);
print(
    '2D array image cols masked (pixel):',
    samp_arr_img(array_img_2d_mask_cols).getInfo()
)
# [[0, 2],
#  [4, 5]]

# Slice out a column to use as a row mask.
col_as_mask_for_rows = array_img_2d.arraySlice(1, 1, 2)
print('2D mask for rows (pixel):', samp_arr_img(col_as_mask_for_rows).getInfo())
# [[1],
#  [0]]

array_img_2d_mask_rows = array_img_2d.arrayMask(col_as_mask_for_rows)
print(
    '2D array image rows masked (pixel):',
    samp_arr_img(array_img_2d_mask_rows).getInfo()
)
# [[0, 1, 2]]