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ImageClassifier

public final class ImageClassifier

Performs classification on images.

The API expects a TFLite model with optional, but strongly recommended, TFLite Model Metadata..

The API supports models with one image input tensor and one classification output tensor. To be more specific, here are the requirements.

  • Input image tensor (kTfLiteUInt8/kTfLiteFloat32)
    • image input of size [batch x height x width x channels].
    • batch inference is not supported (batch is required to be 1).
    • only RGB inputs are supported (channels is required to be 3).
    • if type is kTfLiteFloat32, NormalizationOptions are required to be attached to the metadata for input normalization.
  • Output score tensor (kTfLiteUInt8/kTfLiteFloat32)
    • with N classes of either 2 or 4 dimensions, such as [1 x N] or [1 x 1 x 1 x N]
    • the label file is required to be packed to the metadata. See the example of creating metadata for an image classifier. If no label files are packed, it will use index as label in the result.

An example of such model can be found on TensorFlow Hub..

Nested Classes

class ImageClassifier.ImageClassifierOptions Options for setting up an ImageClassifier. 

Public Methods

List<Classifications>
classify(TensorImage image)
Performs actual classification on the provided TensorImage.
List<Classifications>
classify(TensorImage image, ImageProcessingOptions options)
Performs actual classification on the provided TensorImage with ImageProcessingOptions.
List<Classifications>
classify(MlImage image)
Performs actual classification on the provided MlImage.
List<Classifications>
classify(MlImage image, ImageProcessingOptions options)
Performs actual classification on the provided MlImage with ImageProcessingOptions.
static ImageClassifier
createFromBuffer(ByteBuffer modelBuffer)
Creates an ImageClassifier instance with a model buffer and the default ImageClassifier.ImageClassifierOptions.
static ImageClassifier
static ImageClassifier
createFromFile(Context context, String modelPath)
Creates an ImageClassifier instance from the default ImageClassifier.ImageClassifierOptions.
static ImageClassifier
createFromFile(File modelFile)
Creates an ImageClassifier instance from the default ImageClassifier.ImageClassifierOptions.
static ImageClassifier
static ImageClassifier

Inherited Methods

Public Methods

public List<Classifications> classify (TensorImage image)

Performs actual classification on the provided TensorImage.

ImageClassifier supports the following TensorImage color space types:

Parameters
image a UINT8 TensorImage object that represents an RGB or YUV image
Throws
IllegalArgumentException if the color space type of image is unsupported

public List<Classifications> classify (TensorImage image, ImageProcessingOptions options)

Performs actual classification on the provided TensorImage with ImageProcessingOptions.

ImageClassifier supports the following options:

ImageClassifier supports the following TensorImage color space types:

Parameters
image a UINT8 TensorImage object that represents an RGB or YUV image
options
Throws
IllegalArgumentException if the color space type of image is unsupported

public List<Classifications> classify (MlImage image)

Performs actual classification on the provided MlImage.

Parameters
image an MlImage object that represents an image
Throws
IllegalArgumentException if the storage type or format of the image is unsupported

public List<Classifications> classify (MlImage image, ImageProcessingOptions options)

Performs actual classification on the provided MlImage with ImageProcessingOptions.

ImageClassifier supports the following options:

Parameters
image a MlImage object that represents an image
options configures options including ROI and rotation
Throws
IllegalArgumentException if the storage type or format of the image is unsupported

public static ImageClassifier createFromBuffer (ByteBuffer modelBuffer)

Creates an ImageClassifier instance with a model buffer and the default ImageClassifier.ImageClassifierOptions.

Parameters
modelBuffer a direct ByteBuffer or a MappedByteBuffer of the classification model
Throws
IllegalArgumentException if the model buffer is not a direct ByteBuffer or a MappedByteBuffer
IllegalStateException if there is an internal error
RuntimeException if there is an otherwise unspecified error

public static ImageClassifier createFromBufferAndOptions (ByteBuffer modelBuffer, ImageClassifier.ImageClassifierOptions options)

Creates an ImageClassifier instance with a model buffer and ImageClassifier.ImageClassifierOptions.

Parameters
modelBuffer a direct ByteBuffer or a MappedByteBuffer of the classification model
options
Throws
IllegalArgumentException if the model buffer is not a direct ByteBuffer or a MappedByteBuffer
IllegalStateException if there is an internal error
RuntimeException if there is an otherwise unspecified error

public static ImageClassifier createFromFile (Context context, String modelPath)

Creates an ImageClassifier instance from the default ImageClassifier.ImageClassifierOptions.

Parameters
context
modelPath path of the classification model with metadata in the assets
Throws
IOException if an I/O error occurs when loading the tflite model
IllegalArgumentException if an argument is invalid
IllegalStateException if there is an internal error
RuntimeException if there is an otherwise unspecified error

public static ImageClassifier createFromFile (File modelFile)

Creates an ImageClassifier instance from the default ImageClassifier.ImageClassifierOptions.

Parameters
modelFile the classification model File instance
Throws
IOException if an I/O error occurs when loading the tflite model
IllegalArgumentException if an argument is invalid
IllegalStateException if there is an internal error
RuntimeException if there is an otherwise unspecified error

public static ImageClassifier createFromFileAndOptions (Context context, String modelPath, ImageClassifier.ImageClassifierOptions options)

Parameters
context
modelPath path of the classification model with metadata in the assets
options
Throws
IOException if an I/O error occurs when loading the tflite model
IllegalArgumentException if an argument is invalid
IllegalStateException if there is an internal error
RuntimeException if there is an otherwise unspecified error

public static ImageClassifier createFromFileAndOptions (File modelFile, ImageClassifier.ImageClassifierOptions options)

Creates an ImageClassifier instance.

Parameters
modelFile the classification model File instance
options
Throws
IOException if an I/O error occurs when loading the tflite model
IllegalArgumentException if an argument is invalid
IllegalStateException if there is an internal error
RuntimeException if there is an otherwise unspecified error