OnnxCatalog.DnnFeaturizeImage 方法
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
Create DnnImageFeaturizerEstimator,該工具會將預先訓練好的 DNN 模型應用於 中 DnnImageModelSelector ,來裝飾一張影像。
public static Microsoft.ML.Transforms.Onnx.DnnImageFeaturizerEstimator DnnFeaturizeImage(this Microsoft.ML.TransformsCatalog catalog, string outputColumnName, Func<Microsoft.ML.Transforms.Onnx.DnnImageFeaturizerInput,Microsoft.ML.Data.EstimatorChain<Microsoft.ML.Transforms.ColumnCopyingTransformer>> modelFactory, string inputColumnName = default);
static member DnnFeaturizeImage : Microsoft.ML.TransformsCatalog * string * Func<Microsoft.ML.Transforms.Onnx.DnnImageFeaturizerInput, Microsoft.ML.Data.EstimatorChain<Microsoft.ML.Transforms.ColumnCopyingTransformer>> * string -> Microsoft.ML.Transforms.Onnx.DnnImageFeaturizerEstimator
<Extension()>
Public Function DnnFeaturizeImage (catalog As TransformsCatalog, outputColumnName As String, modelFactory As Func(Of DnnImageFeaturizerInput, EstimatorChain(Of ColumnCopyingTransformer)), Optional inputColumnName As String = Nothing) As DnnImageFeaturizerEstimator
參數
- catalog
- TransformsCatalog
變身者的目錄。
- outputColumnName
- String
由 的 inputColumnName轉換所產生的欄位名稱。
- modelFactory
- Func<DnnImageFeaturizerInput,EstimatorChain<ColumnCopyingTransformer>>
在 上的 DnnImageModelSelector 一個擴充方法會產生一條兩 OnnxScoringEstimator 條鏈(一條用於預處理,一條用預訓練的影像 DNN),並將特定模型與該擴充方法一起包含在套件中。
- inputColumnName
- String
要變換的欄位名稱。
若設為 null,則 的值 outputColumnName 將作為來源。
傳回
範例
using System.IO;
using System.Linq;
using Microsoft.ML;
using Microsoft.ML.Data;
namespace Samples.Dynamic
{
public static class DnnFeaturizeImage
{
public static void Example()
{
// Create a new ML context, for ML.NET operations. It can be used for
// exception tracking and logging, as well as the source of randomness.
var mlContext = new MLContext();
// Downloading a few images, and an images.tsv file, which contains a
// list of the files from the dotnet/machinelearning/test/data/images/.
// If you inspect the fileSystem, after running this line, an "images"
// folder will be created, containing 4 images, and a .tsv file
// enumerating the images.
var imagesDataFile = Microsoft.ML.SamplesUtils.DatasetUtils
.GetSampleImages();
// Preview of the content of the images.tsv file, which lists the images
// to operate on
//
// imagePath imageType
// tomato.bmp tomato
// banana.jpg banana
// hotdog.jpg hotdog
// tomato.jpg tomato
var data = mlContext.Data.CreateTextLoader(new TextLoader.Options()
{
Columns = new[]
{
new TextLoader.Column("ImagePath", DataKind.String, 0),
new TextLoader.Column("Name", DataKind.String, 1),
}
}).Load(imagesDataFile);
var imagesFolder = Path.GetDirectoryName(imagesDataFile);
// Installing the Microsoft.ML.DNNImageFeaturizer packages copies the models in the
// `DnnImageModels` folder.
// Image loading pipeline.
var pipeline = mlContext.Transforms.LoadImages("ImageObject",
imagesFolder, "ImagePath")
.Append(mlContext.Transforms.ResizeImages("ImageObject", imageWidth:
224, imageHeight: 224))
.Append(mlContext.Transforms.ExtractPixels("Pixels", "ImageObject"))
.Append(mlContext.Transforms.DnnFeaturizeImage("FeaturizedImage",
m => m.ModelSelector.ResNet18(mlContext, m.OutputColumn, m
.InputColumn), "Pixels"));
var transformedData = pipeline.Fit(data).Transform(data);
var FeaturizedImageColumnsPerRow = transformedData.GetColumn<float[]>(
"FeaturizedImage").ToArray();
// Preview of FeaturizedImageColumnsPerRow for the first row,
// FeaturizedImageColumnsPerRow[0]
//
// 0.696136236
// 0.2661711
// 0.440882325
// 0.157903448
// 0.0339231342
// 0
// 0.0936501548
// 0.159010679
// 0.394427955
}
}
}