MNN/tools/train/source/demo/ImageDatasetDemo.cpp

102 lines
3.3 KiB
C++

//
// ImageDatasetDemo.cpp
// MNN
//
// Created by MNN on 2019/11/20.
// Copyright © 2018, Alibaba Group Holding Limited
//
#include <iostream>
#include "DataLoader.hpp"
#include "DemoUnit.hpp"
#include "ImageDataset.hpp"
#include "RandomSampler.hpp"
#include "Sampler.hpp"
#include "Transform.hpp"
#include "TransformDataset.hpp"
#ifdef MNN_USE_OPENCV
#include <opencv2/opencv.hpp> // use opencv to show pictures
using namespace cv;
#endif
using namespace std;
using namespace MNN;
using namespace MNN::Train;
/*
* this is an demo for how to use the ImageDataset and DataLoader
*/
class ImageDatasetDemo : public DemoUnit {
public:
// this function is an example to use the lambda transform
// here we use lambda transform to normalize data from 0~255 to 0~1
static Example func(Example example) {
// // an easier way to do this
auto cast = _Cast(example.first[0], halide_type_of<float>());
example.first[0] = _Multiply(cast, _Const(1.0f / 255.0f));
return example;
}
virtual int run(int argc, const char* argv[]) override {
if (argc != 3) {
cout << "usage: ./runTrainDemo.out ImageDatasetDemo path/to/images/ path/to/image/txt\n" << endl;
cout << "the ImageDataset read stored images as input data.\n"
"use 'pathToImages' and a txt file to construct a ImageDataset.\n"
"the txt file should use format as below:\n"
" image1.jpg label1,label2,...\n"
" image2.jpg label3,label4,...\n"
" ...\n"
"the ImageDataset would read images from:\n"
" pathToImages/image1.jpg\n"
" pathToImages/image2.jpg\n"
" ...\n"
<< endl;
return 0;
}
std::string pathToImages = argv[1];
std::string pathToImageTxt = argv[2];
auto converImagesToFormat = CV::RGB;
int resizeHeight = 224;
int resizeWidth = 224;
std::vector<float> scales = {1/255.0f, 1/255.0f, 1/255.0f};
std::shared_ptr<ImageDataset::ImageConfig> config(ImageDataset::ImageConfig::create(converImagesToFormat, resizeHeight, resizeWidth, scales));
bool readAllImagesToMemory = false;
auto dataset = ImageDataset::create(pathToImages, pathToImageTxt, config.get(), readAllImagesToMemory);
const int batchSize = 1;
const int numWorkers = 1;
auto dataLoader = dataset.createLoader(batchSize, true, false, numWorkers);
const size_t iterations =dataLoader->iterNumber();
for (int i = 0; i < iterations; i++) {
auto trainData = dataLoader->next();
auto data = trainData[0].first[0]->readMap<float_t>();
auto label = trainData[0].second[0]->readMap<int32_t>();
cout << "index: " << i << " label: " << int(label[0]) << endl;
#ifdef MNN_USE_OPENCV
// only show the first picture in the batch
Mat image = Mat(resizeHeight, resizeWidth, CV_32FC(3), (void*)data);
imshow("image", image);
waitKey(-1);
#endif
}
// this will reset the sampler's internal state
dataLoader->reset();
return 0;
}
};
DemoUnitSetRegister(ImageDatasetDemo, "ImageDatasetDemo");