1 /* Copyright 2017 The TensorFlow Authors. All Rights Reserved. 2 3 Licensed under the Apache License, Version 2.0 (the "License"); 4 you may not use this file except in compliance with the License. 5 You may obtain a copy of the License at 6 7 http://www.apache.org/licenses/LICENSE-2.0 8 9 Unless required by applicable law or agreed to in writing, software 10 distributed under the License is distributed on an "AS IS" BASIS, 11 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 See the License for the specific language governing permissions and 13 limitations under the License. 14 ==============================================================================*/ 15 16 package org.tensorflow.lite; 17 18 import java.io.File; 19 import java.nio.ByteBuffer; 20 import java.util.Arrays; 21 import java.util.Map; 22 // Use Android annotation instead 23 import android.support.annotation.NonNull; 24 // import org.checkerframework.checker.nullness.qual.NonNull; 25 26 /** 27 * Driver class to drive model inference with TensorFlow Lite. 28 * 29 * <p>Note: If you don't need access to any of the "experimental" API features below, prefer to use 30 * InterpreterApi and InterpreterFactory rather than using Interpreter directly. 31 * 32 * <p>A {@code Interpreter} encapsulates a pre-trained TensorFlow Lite model, in which operations 33 * are executed for model inference. 34 * 35 * <p>For example, if a model takes only one input and returns only one output: 36 * 37 * <pre>{@code 38 * try (Interpreter interpreter = new Interpreter(file_of_a_tensorflowlite_model)) { 39 * interpreter.run(input, output); 40 * } 41 * }</pre> 42 * 43 * <p>If a model takes multiple inputs or outputs: 44 * 45 * <pre>{@code 46 * Object[] inputs = {input0, input1, ...}; 47 * Map<Integer, Object> map_of_indices_to_outputs = new HashMap<>(); 48 * FloatBuffer ith_output = FloatBuffer.allocateDirect(3 * 2 * 4); // Float tensor, shape 3x2x4. 49 * ith_output.order(ByteOrder.nativeOrder()); 50 * map_of_indices_to_outputs.put(i, ith_output); 51 * try (Interpreter interpreter = new Interpreter(file_of_a_tensorflowlite_model)) { 52 * interpreter.runForMultipleInputsOutputs(inputs, map_of_indices_to_outputs); 53 * } 54 * }</pre> 55 * 56 * <p>If a model takes or produces string tensors: 57 * 58 * <pre>{@code 59 * String[] input = {"foo", "bar"}; // Input tensor shape is [2]. 60 * String[] output = new String[3][2]; // Output tensor shape is [3, 2]. 61 * try (Interpreter interpreter = new Interpreter(file_of_a_tensorflowlite_model)) { 62 * interpreter.runForMultipleInputsOutputs(input, output); 63 * } 64 * }</pre> 65 * 66 * <p>Orders of inputs and outputs are determined when converting TensorFlow model to TensorFlowLite 67 * model with Toco, as are the default shapes of the inputs. 68 * 69 * <p>When inputs are provided as (multi-dimensional) arrays, the corresponding input tensor(s) will 70 * be implicitly resized according to that array's shape. When inputs are provided as {@code Buffer} 71 * types, no implicit resizing is done; the caller must ensure that the {@code Buffer} byte size 72 * either matches that of the corresponding tensor, or that they first resize the tensor via {@link 73 * #resizeInput(int, int[])}. Tensor shape and type information can be obtained via the {@link 74 * Tensor} class, available via {@link #getInputTensor(int)} and {@link #getOutputTensor(int)}. 75 * 76 * <p><b>WARNING:</b>{@code Interpreter} instances are <b>not</b> thread-safe. A {@code Interpreter} 77 * owns resources that <b>must</b> be explicitly freed by invoking {@link #close()} 78 * 79 * <p>The TFLite library is built against NDK API 19. It may work for Android API levels below 19, 80 * but is not guaranteed. 81 */ 82 public final class Interpreter extends InterpreterImpl implements InterpreterApi { 83 84 /** An options class for controlling runtime interpreter behavior. */ 85 public static class Options extends InterpreterImpl.Options { Options()86 public Options() { 87 } 88 Options(InterpreterApi.Options options)89 public Options(InterpreterApi.Options options) { 90 super(options); 91 } 92 Options(InterpreterImpl.Options options)93 Options(InterpreterImpl.Options options) { 94 super(options); 95 } 96 97 @Override setNumThreads(int numThreads)98 public Options setNumThreads(int numThreads) { 99 super.setNumThreads(numThreads); 100 return this; 101 } 102 103 @Override setUseNNAPI(boolean useNNAPI)104 public Options setUseNNAPI(boolean useNNAPI) { 105 super.setUseNNAPI(useNNAPI); 106 return this; 107 } 108 109 /** 110 * Sets whether to allow float16 precision for FP32 calculation when possible. Defaults to false 111 * (disallow). 112 * 113 * @deprecated Prefer using <a 114 * href="https://github.com/tensorflow/tensorflow/blob/5dc7f6981fdaf74c8c5be41f393df705841fb7c5/tensorflow/lite/delegates/nnapi/java/src/main/java/org/tensorflow/lite/nnapi/NnApiDelegate.java#L127">NnApiDelegate.Options#setAllowFp16(boolean 115 * enable)</a>. 116 */ 117 @Deprecated setAllowFp16PrecisionForFp32(boolean allow)118 public Options setAllowFp16PrecisionForFp32(boolean allow) { 119 this.allowFp16PrecisionForFp32 = allow; 120 return this; 121 } 122 123 @Override addDelegate(Delegate delegate)124 public Options addDelegate(Delegate delegate) { 125 super.addDelegate(delegate); 126 return this; 127 } 128 129 /** 130 * Advanced: Set if buffer handle output is allowed. 131 * 132 * <p>When a {@link Delegate} supports hardware acceleration, the interpreter will make the data 133 * of output tensors available in the CPU-allocated tensor buffers by default. If the client can 134 * consume the buffer handle directly (e.g. reading output from OpenGL texture), it can set this 135 * flag to false, avoiding the copy of data to the CPU buffer. The delegate documentation should 136 * indicate whether this is supported and how it can be used. 137 * 138 * <p>WARNING: This is an experimental interface that is subject to change. 139 */ setAllowBufferHandleOutput(boolean allow)140 public Options setAllowBufferHandleOutput(boolean allow) { 141 this.allowBufferHandleOutput = allow; 142 return this; 143 } 144 145 @Override setCancellable(boolean allow)146 public Options setCancellable(boolean allow) { 147 super.setCancellable(allow); 148 return this; 149 } 150 151 /** 152 * Experimental: Enable an optimized set of floating point CPU kernels (provided by XNNPACK). 153 * 154 * <p>Enabling this flag will enable use of a new, highly optimized set of CPU kernels provided 155 * via the XNNPACK delegate. Currently, this is restricted to a subset of floating point 156 * operations. Eventually, we plan to enable this by default, as it can provide significant 157 * peformance benefits for many classes of floating point models. See 158 * https://github.com/tensorflow/tensorflow/blob/master/tensorflow/lite/delegates/xnnpack/README.md 159 * for more details. 160 * 161 * <p>Things to keep in mind when enabling this flag: 162 * 163 * <ul> 164 * <li>Startup time and resize time may increase. 165 * <li>Baseline memory consumption may increase. 166 * <li>May be ignored if another delegate (eg NNAPI) have been applied. 167 * <li>Quantized models will not see any benefit. 168 * </ul> 169 * 170 * <p>WARNING: This is an experimental interface that is subject to change. 171 */ setUseXNNPACK(boolean useXNNPACK)172 public Options setUseXNNPACK(boolean useXNNPACK) { 173 this.useXNNPACK = useXNNPACK; 174 return this; 175 } 176 } 177 178 /** 179 * Initializes an {@code Interpreter}. 180 * 181 * @param modelFile a File of a pre-trained TF Lite model. 182 * @throws IllegalArgumentException if {@code modelFile} does not encode a valid TensorFlow Lite 183 * model. 184 */ Interpreter(@onNull File modelFile)185 public Interpreter(@NonNull File modelFile) { 186 this(modelFile, /*options = */ null); 187 } 188 189 /** 190 * Initializes an {@code Interpreter} and specifies options for customizing interpreter behavior. 191 * 192 * @param modelFile a file of a pre-trained TF Lite model 193 * @param options a set of options for customizing interpreter behavior 194 * @throws IllegalArgumentException if {@code modelFile} does not encode a valid TensorFlow Lite 195 * model. 196 */ Interpreter(@onNull File modelFile, Options options)197 public Interpreter(@NonNull File modelFile, Options options) { 198 this(new NativeInterpreterWrapperExperimental(modelFile.getAbsolutePath(), options)); 199 } 200 201 /** 202 * Initializes an {@code Interpreter} with a {@code ByteBuffer} of a model file. 203 * 204 * <p>The ByteBuffer should not be modified after the construction of a {@code Interpreter}. The 205 * {@code ByteBuffer} can be either a {@code MappedByteBuffer} that memory-maps a model file, or a 206 * direct {@code ByteBuffer} of nativeOrder() that contains the bytes content of a model. 207 * 208 * @throws IllegalArgumentException if {@code byteBuffer} is not a {@code MappedByteBuffer} nor a 209 * direct {@code ByteBuffer} of nativeOrder. 210 */ Interpreter(@onNull ByteBuffer byteBuffer)211 public Interpreter(@NonNull ByteBuffer byteBuffer) { 212 this(byteBuffer, /* options= */ null); 213 } 214 215 /** 216 * Initializes an {@code Interpreter} with a {@code ByteBuffer} of a model file and a set of 217 * custom {@link Interpreter.Options}. 218 * 219 * <p>The {@code ByteBuffer} should not be modified after the construction of an {@code 220 * Interpreter}. The {@code ByteBuffer} can be either a {@code MappedByteBuffer} that memory-maps 221 * a model file, or a direct {@code ByteBuffer} of nativeOrder() that contains the bytes content 222 * of a model. 223 * 224 * @throws IllegalArgumentException if {@code byteBuffer} is not a {@code MappedByteBuffer} nor a 225 * direct {@code ByteBuffer} of nativeOrder. 226 */ Interpreter(@onNull ByteBuffer byteBuffer, Options options)227 public Interpreter(@NonNull ByteBuffer byteBuffer, Options options) { 228 this(new NativeInterpreterWrapperExperimental(byteBuffer, options)); 229 } 230 Interpreter(NativeInterpreterWrapperExperimental wrapper)231 private Interpreter(NativeInterpreterWrapperExperimental wrapper) { 232 super(wrapper); 233 wrapperExperimental = wrapper; 234 signatureKeyList = getSignatureKeys(); 235 } 236 237 /** 238 * Runs model inference based on SignatureDef provided through {@code signatureKey}. 239 * 240 * <p>See {@link Interpreter#run(Object, Object)} for more details on the allowed input and output 241 * data types. 242 * 243 * <p>WARNING: This is an experimental API and subject to change. 244 * 245 * @param inputs A map from input name in the SignatureDef to an input object. 246 * @param outputs A map from output name in SignatureDef to output data. This may be empty if the 247 * caller wishes to query the {@link Tensor} data directly after inference (e.g., if the 248 * output shape is dynamic, or output buffer handles are used). 249 * @param signatureKey Signature key identifying the SignatureDef. 250 * @throws IllegalArgumentException if {@code inputs} is null or empty, if {@code outputs} or 251 * {@code signatureKey} is null, or if an error occurs when running inference. 252 */ runSignature( @onNull Map<String, Object> inputs, @NonNull Map<String, Object> outputs, String signatureKey)253 public void runSignature( 254 @NonNull Map<String, Object> inputs, 255 @NonNull Map<String, Object> outputs, 256 String signatureKey) { 257 checkNotClosed(); 258 if (signatureKey == null && signatureKeyList.length == 1) { 259 signatureKey = signatureKeyList[0]; 260 } 261 if (signatureKey == null) { 262 throw new IllegalArgumentException( 263 "Input error: SignatureDef signatureKey should not be null. null is only allowed if the" 264 + " model has a single Signature. Available Signatures: " 265 + Arrays.toString(signatureKeyList)); 266 } 267 wrapper.runSignature(inputs, outputs, signatureKey); 268 } 269 270 /** 271 * Same as {@link #runSignature(Map, Map, String)} but doesn't require passing a signatureKey, 272 * assuming the model has one SignatureDef. If the model has more than one SignatureDef it will 273 * throw an exception. 274 * 275 * <p>WARNING: This is an experimental API and subject to change. 276 */ runSignature( @onNull Map<String, Object> inputs, @NonNull Map<String, Object> outputs)277 public void runSignature( 278 @NonNull Map<String, Object> inputs, @NonNull Map<String, Object> outputs) { 279 checkNotClosed(); 280 runSignature(inputs, outputs, null); 281 } 282 283 /** 284 * Gets the Tensor associated with the provdied input name and signature method name. 285 * 286 * <p>WARNING: This is an experimental API and subject to change. 287 * 288 * @param inputName Input name in the signature. 289 * @param signatureKey Signature key identifying the SignatureDef, can be null if the model has 290 * one signature. 291 * @throws IllegalArgumentException if {@code inputName} or {@code signatureKey} is null or empty, 292 * or invalid name provided. 293 */ getInputTensorFromSignature(String inputName, String signatureKey)294 public Tensor getInputTensorFromSignature(String inputName, String signatureKey) { 295 checkNotClosed(); 296 if (signatureKey == null && signatureKeyList.length == 1) { 297 signatureKey = signatureKeyList[0]; 298 } 299 if (signatureKey == null) { 300 throw new IllegalArgumentException( 301 "Input error: SignatureDef signatureKey should not be null. null is only allowed if the" 302 + " model has a single Signature. Available Signatures: " 303 + Arrays.toString(signatureKeyList)); 304 } 305 return wrapper.getInputTensor(inputName, signatureKey); 306 } 307 308 /** 309 * Gets the list of SignatureDef exported method names available in the model. 310 * 311 * <p>WARNING: This is an experimental API and subject to change. 312 */ getSignatureKeys()313 public String[] getSignatureKeys() { 314 checkNotClosed(); 315 return wrapper.getSignatureKeys(); 316 } 317 318 /** 319 * Gets the list of SignatureDefs inputs for method {@code signatureKey}. 320 * 321 * <p>WARNING: This is an experimental API and subject to change. 322 */ getSignatureInputs(String signatureKey)323 public String[] getSignatureInputs(String signatureKey) { 324 checkNotClosed(); 325 return wrapper.getSignatureInputs(signatureKey); 326 } 327 328 /** 329 * Gets the list of SignatureDefs outputs for method {@code signatureKey}. 330 * 331 * <p>WARNING: This is an experimental API and subject to change. 332 */ getSignatureOutputs(String signatureKey)333 public String[] getSignatureOutputs(String signatureKey) { 334 checkNotClosed(); 335 return wrapper.getSignatureOutputs(signatureKey); 336 } 337 338 /** 339 * Gets the Tensor associated with the provdied output name in specifc signature method. 340 * 341 * <p>Note: Output tensor details (e.g., shape) may not be fully populated until after inference 342 * is executed. If you need updated details *before* running inference (e.g., after resizing an 343 * input tensor, which may invalidate output tensor shapes), use {@link #allocateTensors()} to 344 * explicitly trigger allocation and shape propagation. Note that, for graphs with output shapes 345 * that are dependent on input *values*, the output shape may not be fully determined until 346 * running inference. 347 * 348 * <p>WARNING: This is an experimental API and subject to change. 349 * 350 * @param outputName Output name in the signature. 351 * @param signatureKey Signature key identifying the SignatureDef, can be null if the model has 352 * one signature. 353 * @throws IllegalArgumentException if {@code outputName} or {@code signatureKey} is null or 354 * empty, or invalid name provided. 355 */ getOutputTensorFromSignature(String outputName, String signatureKey)356 public Tensor getOutputTensorFromSignature(String outputName, String signatureKey) { 357 checkNotClosed(); 358 if (signatureKey == null && signatureKeyList.length == 1) { 359 signatureKey = signatureKeyList[0]; 360 } 361 if (signatureKey == null) { 362 throw new IllegalArgumentException( 363 "Input error: SignatureDef signatureKey should not be null. null is only allowed if the" 364 + " model has a single Signature. Available Signatures: " 365 + Arrays.toString(signatureKeyList)); 366 } 367 return wrapper.getOutputTensor(outputName, signatureKey); 368 } 369 370 /** 371 * Advanced: Resets all variable tensors to the default value. 372 * 373 * <p>If a variable tensor doesn't have an associated buffer, it will be reset to zero. 374 * 375 * <p>WARNING: This is an experimental API and subject to change. 376 */ resetVariableTensors()377 public void resetVariableTensors() { 378 checkNotClosed(); 379 wrapperExperimental.resetVariableTensors(); 380 } 381 382 /** 383 * Advanced: Interrupts inference in the middle of a call to {@link Interpreter#run}. 384 * 385 * <p>A cancellation flag will be set to true when this function gets called. The interpreter will 386 * check the flag between Op invocations, and if it's {@code true}, the interpreter will stop 387 * execution. The interpreter will remain a cancelled state until explicitly "uncancelled" by 388 * {@code setCancelled(false)}. 389 * 390 * <p>WARNING: This is an experimental API and subject to change. 391 * 392 * @param cancelled {@code true} to cancel inference in a best-effort way; {@code false} to 393 * resume. 394 * @throws IllegalStateException if the interpreter is not initialized with the cancellable 395 * option, which is by default off. 396 * @see Interpreter.Options#setCancellable(boolean). 397 */ setCancelled(boolean cancelled)398 public void setCancelled(boolean cancelled) { 399 wrapper.setCancelled(cancelled); 400 } 401 402 NativeInterpreterWrapperExperimental wrapperExperimental; 403 String[] signatureKeyList; 404 } 405