Pengumuman: Semua project nonkomersial yang terdaftar untuk menggunakan Earth Engine sebelum
15 April 2025 harus
memverifikasi kelayakan nonkomersial untuk mempertahankan akses Earth Engine.
ui.Chart.image.histogram
Tetap teratur dengan koleksi
Simpan dan kategorikan konten berdasarkan preferensi Anda.
Membuat Diagram dari gambar. Menghitung dan memetakan histogram nilai band di wilayah gambar yang ditentukan.
- Sumbu X: Bucket histogram (nilai rentang).
- Sumbu Y: Frekuensi (jumlah piksel dengan nilai rentang dalam bucket).
Menampilkan diagram.
Penggunaan | Hasil |
---|
ui.Chart.image.histogram(image, region, scale, maxBuckets, minBucketWidth, maxRaw, maxPixels) | ui.Chart |
Argumen | Jenis | Detail |
---|
image | Gambar | Gambar untuk membuat histogram. |
region | Fitur|FeatureCollection|Geometri, opsional | Wilayah yang akan dikurangi. Jika tidak ada, gunakan seluruh gambar. |
scale | Nomor, opsional | Skala piksel yang digunakan saat menerapkan peredam histogram, dalam meter. |
maxBuckets | Nomor, opsional | Jumlah maksimum bucket yang akan digunakan saat membuat histogram; akan dibulatkan ke atas menjadi pangkat 2. |
minBucketWidth | Nomor, opsional | Lebar bucket histogram minimum, atau null untuk mengizinkan pangkat 2 apa pun. |
maxRaw | Nomor, opsional | Jumlah nilai yang akan diakumulasikan sebelum membuat histogram awal. |
maxPixels | Nomor, opsional | Jika ditentukan, menggantikan jumlah maksimum piksel yang diizinkan dalam pengurangan histogram. Nilai defaultnya adalah 1e6. |
Contoh
Code Editor (JavaScript)
// Define a MODIS surface reflectance composite.
var modisSr = ee.ImageCollection('MODIS/006/MOD09A1')
.filter(ee.Filter.date('2018-06-01', '2018-09-01'))
.select(['sur_refl_b01', 'sur_refl_b02', 'sur_refl_b06'])
.mean();
// Define a region to calculate histogram for.
var histRegion = ee.Geometry.Rectangle([-112.60, 40.60, -111.18, 41.22]);
// Define the chart and print it to the console.
var chart =
ui.Chart.image.histogram({image: modisSr, region: histRegion, scale: 500})
.setSeriesNames(['Red', 'NIR', 'SWIR'])
.setOptions({
title: 'MODIS SR Reflectance Histogram',
hAxis: {
title: 'Reflectance (scaled by 1e4)',
titleTextStyle: {italic: false, bold: true},
},
vAxis:
{title: 'Count', titleTextStyle: {italic: false, bold: true}},
colors: ['cf513e', '1d6b99', 'f0af07']
});
print(chart);
Kecuali dinyatakan lain, konten di halaman ini dilisensikan berdasarkan Lisensi Creative Commons Attribution 4.0, sedangkan contoh kode dilisensikan berdasarkan Lisensi Apache 2.0. Untuk mengetahui informasi selengkapnya, lihat Kebijakan Situs Google Developers. Java adalah merek dagang terdaftar dari Oracle dan/atau afiliasinya.
Terakhir diperbarui pada 2025-07-26 UTC.
[null,null,["Terakhir diperbarui pada 2025-07-26 UTC."],[[["\u003cp\u003eGenerates a chart displaying the frequency distribution of pixel values within a specified image region.\u003c/p\u003e\n"],["\u003cp\u003eThe chart plots histograms for each band of the image, showing the number of pixels with values falling within specific ranges (buckets).\u003c/p\u003e\n"],["\u003cp\u003eUsers can customize the chart by defining the region, scale, and bucket parameters, as well as the maximum number of input values and pixels used in the calculation.\u003c/p\u003e\n"],["\u003cp\u003eThe chart is rendered with customizable axes, titles, and color options for each band.\u003c/p\u003e\n"],["\u003cp\u003e\u003ccode\u003eui.Chart.image.histogram()\u003c/code\u003e returns a \u003ccode\u003eui.Chart\u003c/code\u003e object, allowing for further manipulation and display within the Earth Engine Code Editor.\u003c/p\u003e\n"]]],["This code generates a histogram chart from an image, plotting band values against their frequency. It utilizes `ui.Chart.image.histogram` with arguments like `image`, `region`, and `scale` to define the data and spatial parameters. Optional settings include `maxBuckets`, `minBucketWidth`, `maxRaw`, and `maxPixels`. The x-axis represents histogram buckets (band value), while the y-axis shows frequency (pixel count). The example demonstrates its application with MODIS surface reflectance data, defining a region and customizing chart appearance.\n"],null,["# ui.Chart.image.histogram\n\n\u003cbr /\u003e\n\nGenerates a Chart from an image. Computes and plots histograms of the values of the bands in the specified region of the image.\n\n\u003cbr /\u003e\n\n- X-axis: Histogram buckets (of band value).\n\n- Y-axis: Frequency (number of pixels with a band value in the bucket).\n\nReturns a chart.\n\n| Usage | Returns |\n|------------------------------------------------------------------------------------------------------------------------------|----------|\n| `ui.Chart.image.histogram(image, `*region* `, `*scale* `, `*maxBuckets* `, `*minBucketWidth* `, `*maxRaw* `, `*maxPixels*`)` | ui.Chart |\n\n| Argument | Type | Details |\n|------------------|------------------------------------------------|-----------------------------------------------------------------------------------------------------------|\n| `image` | Image | The image to generate a histogram from. |\n| `region` | Feature\\|FeatureCollection\\|Geometry, optional | The region to reduce. If omitted, uses the entire image. |\n| `scale` | Number, optional | The pixel scale used when applying the histogram reducer, in meters. |\n| `maxBuckets` | Number, optional | The maximum number of buckets to use when building a histogram; will be rounded up to a power of 2. |\n| `minBucketWidth` | Number, optional | The minimum histogram bucket width, or null to allow any power of 2. |\n| `maxRaw` | Number, optional | The number of values to accumulate before building the initial histogram. |\n| `maxPixels` | Number, optional | If specified, overrides the maximum number of pixels allowed in the histogram reduction. Defaults to 1e6. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\n// Define a MODIS surface reflectance composite.\nvar modisSr = ee.ImageCollection('MODIS/006/MOD09A1')\n .filter(ee.Filter.date('2018-06-01', '2018-09-01'))\n .select(['sur_refl_b01', 'sur_refl_b02', 'sur_refl_b06'])\n .mean();\n\n// Define a region to calculate histogram for.\nvar histRegion = ee.Geometry.Rectangle([-112.60, 40.60, -111.18, 41.22]);\n\n// Define the chart and print it to the console.\nvar chart =\n ui.Chart.image.histogram({image: modisSr, region: histRegion, scale: 500})\n .setSeriesNames(['Red', 'NIR', 'SWIR'])\n .setOptions({\n title: 'MODIS SR Reflectance Histogram',\n hAxis: {\n title: 'Reflectance (scaled by 1e4)',\n titleTextStyle: {italic: false, bold: true},\n },\n vAxis:\n {title: 'Count', titleTextStyle: {italic: false, bold: true}},\n colors: ['cf513e', '1d6b99', 'f0af07']\n });\nprint(chart);\n```"]]