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Diffstat (limited to 'tensorflow/contrib/lite/examples/ios/simple/RunModelViewController.mm')
-rw-r--r-- | tensorflow/contrib/lite/examples/ios/simple/RunModelViewController.mm | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/tensorflow/contrib/lite/examples/ios/simple/RunModelViewController.mm b/tensorflow/contrib/lite/examples/ios/simple/RunModelViewController.mm new file mode 100644 index 0000000000..965d830105 --- /dev/null +++ b/tensorflow/contrib/lite/examples/ios/simple/RunModelViewController.mm @@ -0,0 +1,219 @@ +// Copyright 2015 Google Inc. All rights reserved. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +#import "RunModelViewController.h" + +#include <fstream> +#include <iostream> +#include <pthread.h> +#include <unistd.h> +#include <queue> +#include <sstream> +#include <string> + +#include "tensorflow/contrib/lite/kernels/register.h" +#include "tensorflow/contrib/lite/model.h" +#include "tensorflow/contrib/lite/string_util.h" +#include "tensorflow/contrib/lite/tools/mutable_op_resolver.h" + +#include "ios_image_load.h" + +#define LOG(x) std::cerr +#define CHECK(x) if (!(x)) { LOG(ERROR) << #x << "failed"; exit(1); } + +NSString* RunInferenceOnImage(); + +@interface RunModelViewController () +@end + +@implementation RunModelViewController { +} + +- (IBAction)getUrl:(id)sender { + NSString* inference_result = RunInferenceOnImage(); + self.urlContentTextView.text = inference_result; +} + +@end + +// Returns the top N confidence values over threshold in the provided vector, +// sorted by confidence in descending order. +static void GetTopN( + const float* prediction, + const int prediction_size, + const int num_results, const float threshold, + std::vector<std::pair<float, int> >* top_results) { + // Will contain top N results in ascending order. + std::priority_queue<std::pair<float, int>, + std::vector<std::pair<float, int> >, + std::greater<std::pair<float, int> > > top_result_pq; + + const long count = prediction_size; + for (int i = 0; i < count; ++i) { + const float value = prediction[i]; + + // Only add it if it beats the threshold and has a chance at being in + // the top N. + if (value < threshold) { + continue; + } + + top_result_pq.push(std::pair<float, int>(value, i)); + + // If at capacity, kick the smallest value out. + if (top_result_pq.size() > num_results) { + top_result_pq.pop(); + } + } + + // Copy to output vector and reverse into descending order. + while (!top_result_pq.empty()) { + top_results->push_back(top_result_pq.top()); + top_result_pq.pop(); + } + std::reverse(top_results->begin(), top_results->end()); +} + +NSString* FilePathForResourceName(NSString* name, NSString* extension) { + NSString* file_path = [[NSBundle mainBundle] pathForResource:name ofType:extension]; + if (file_path == NULL) { + LOG(FATAL) << "Couldn't find '" << [name UTF8String] << "." + << [extension UTF8String] << "' in bundle."; + } + return file_path; +} + +NSString* RunInferenceOnImage() { + std::string graph; + const int num_threads = 1; + std::string input_layer_type = "float"; + std::vector<int> sizes = {1, 224, 224, 3}; + + NSString* graph_path = FilePathForResourceName(@"mobilenet_v1_1.0_224", @"tflite"); + + std::unique_ptr<tflite::FlatBufferModel> model(tflite::FlatBufferModel::BuildFromFile([graph_path UTF8String])); + if (!model) { + LOG(FATAL) << "Failed to mmap model " << graph; + } + LOG(INFO) << "Loaded model " << graph; + model->error_reporter(); + LOG(INFO) << "resolved reporter"; + +#ifdef TFLITE_CUSTOM_OPS_HEADER + tflite::MutableOpResolver resolver; + RegisterSelectedOps(&resolver); +#else + tflite::ops::builtin::BuiltinOpResolver resolver; +#endif + + std::unique_ptr<tflite::Interpreter> interpreter; + tflite::InterpreterBuilder(*model, resolver)(&interpreter); + if (!interpreter) { + LOG(FATAL) << "Failed to construct interpreter"; + } + + if (num_threads != -1) { + interpreter->SetNumThreads(num_threads); + } + + int input = interpreter->inputs()[0]; + + if (input_layer_type != "string") { + interpreter->ResizeInputTensor(input, sizes); + } + + if (interpreter->AllocateTensors() != kTfLiteOk) { + LOG(FATAL) << "Failed to allocate tensors!"; + } + + // Read the label list + NSString* labels_path = FilePathForResourceName(@"labels", @"txt"); + std::vector<std::string> label_strings; + std::ifstream t; + t.open([labels_path UTF8String]); + std::string line; + while(t){ + std::getline(t, line); + label_strings.push_back(line); + } + t.close(); + + // Read the Grace Hopper image. + NSString* image_path = FilePathForResourceName(@"grace_hopper", @"jpg"); + int image_width; + int image_height; + int image_channels; + std::vector<uint8_t> image_data = LoadImageFromFile([image_path UTF8String], &image_width, &image_height, &image_channels); + const int wanted_width = 224; + const int wanted_height = 224; + const int wanted_channels = 3; + const float input_mean = 127.5f; + const float input_std = 127.5f; + assert(image_channels >= wanted_channels); + uint8_t* in = image_data.data(); + float* out = interpreter->typed_tensor<float>(input); + for (int y = 0; y < wanted_height; ++y) { + const int in_y = (y * image_height) / wanted_height; + uint8_t* in_row = in + (in_y * image_width * image_channels); + float* out_row = out + (y * wanted_width * wanted_channels); + for (int x = 0; x < wanted_width; ++x) { + const int in_x = (x * image_width) / wanted_width; + uint8_t* in_pixel = in_row + (in_x * image_channels); + float* out_pixel = out_row + (x * wanted_channels); + for (int c = 0; c < wanted_channels; ++c) { + out_pixel[c] = (in_pixel[c] - input_mean) / input_std; + } + } + } + + if (interpreter->Invoke() != kTfLiteOk) { + LOG(FATAL) << "Failed to invoke!"; + } + + float* output = interpreter->typed_output_tensor<float>(0); + const int output_size = 1000; + const int kNumResults = 5; + const float kThreshold = 0.1f; + std::vector<std::pair<float, int> > top_results; + GetTopN(output, output_size, kNumResults, kThreshold, &top_results); + + std::stringstream ss; + ss.precision(3); + for (const auto& result : top_results) { + const float confidence = result.first; + const int index = result.second; + + ss << index << " " << confidence << " "; + + // Write out the result as a string + if (index < label_strings.size()) { + // just for safety: theoretically, the output is under 1000 unless there + // is some numerical issues leading to a wrong prediction. + ss << label_strings[index]; + } else { + ss << "Prediction: " << index; + } + + ss << "\n"; + } + + LOG(INFO) << "Predictions: " << ss.str(); + + std::string predictions = ss.str(); + NSString* result = @""; + result = [NSString stringWithFormat: @"%@ - %s", result, + predictions.c_str()]; + + return result; +} |