alexnet.cpp

// Tencent is pleased to support the open source community by making ncnn available.
//
// Copyright (C) 2017 THL A29 Limited, a Tencent company. All rights reserved.
//
// Licensed under the BSD 3-Clause License (the "License"); you may not use this file except
// in compliance with the License. You may obtain a copy of the License at
//
// https://opensource.org/licenses/BSD-3-Clause
//
// 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.

#include "net.h"

#include <algorithm>
#include <opencv2/opencv.hpp>
#include <opencv2/core.hpp>
#include <opencv2/imgproc.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/videoio.hpp>
#include <stdio.h>
#include <vector>
#include <string>

static int detect_alexnet(const cv::Mat& bgr, std::vector<float>& cls_scores)
{
    ncnn::Net alexnet;

    alexnet.opt.use_vulkan_compute = true;

    // the ncnn model https://github.com/nihui/ncnn-assets/tree/master/models
    alexnet.load_param("alexnet.param");
    alexnet.load_model("alexnet.bin");

    ncnn::Mat in = ncnn::Mat::from_pixels_resize(bgr.data, ncnn::Mat::PIXEL_BGR, bgr.cols, bgr.rows, 227, 227);

    const float mean_vals[3] = {104.f, 117.f, 123.f};
    in.substract_mean_normalize(mean_vals, 0);

    ncnn::Extractor ex = alexnet.create_extractor();

    ex.input("data_0", in);

    ncnn::Mat out;
    ex.extract("prob_1", out);

    cls_scores.resize(out.w);
    for (int j = 0; j < out.w; j++)
    {
        cls_scores[j] = out[j];
    }

    return 0;
}

//static int print_topk(const std::vector<float>& cls_scores, int topk)
static int print_topk(const std::vector<float>& cls_scores, int topk, std::vector<int>& index_result, std::vector<float>& score_result)
{
    // partial sort topk with index
    int size = cls_scores.size();
    std::vector<std::pair<float, int> > vec;
    vec.resize(size);
    for (int i = 0; i < size; i++)
    {
        vec[i] = std::make_pair(cls_scores[i], i);
    }

    std::partial_sort(vec.begin(), vec.begin() + topk, vec.end(),
                      std::greater<std::pair<float, int> >());

    // print topk and score
    for (int i = 0; i < topk; i++)
    {
        float score = vec[i].first;
        int index = vec[i].second;
        fprintf(stderr, "%d = %f\n", index, score);
        index_result.push_back(index);
        score_result.push_back(score);

    }

    return 0;
}

static int load_labels(std::string path, std::vector<std::string>& labels)
{
    FILE* fp = fopen(path.c_str(), "r");

    while (!feof(fp))
    {
        char str[1024];
        fgets(str, 1024, fp);  
        std::string str_s(str);

        if (str_s.length() > 0)
        {
            for (int i = 0; i < str_s.length(); i++)
            {
                if (str_s[i] == ' ')
                {
                    std::string strr = str_s.substr(i, str_s.length() - i - 1);
                    labels.push_back(strr);
                    i = str_s.length();
                }
            }
        }
    }
    return 0;
}




int main(int argc, char** argv)
{
    std::vector<std::string> labels;
    load_labels("synset_words.txt", labels);

    if (argc != 2)
    {
        fprintf(stderr, "Usage: %s [imagepath]\n", argv[0]);
        return -1;
    }

    const char* imagepath = argv[1];

    cv::Mat m = cv::imread(imagepath, 1);
    if (m.empty())
    {
        fprintf(stderr, "cv::imread %s failed\n", imagepath);
        return -1;
    }

    std::vector<float> cls_scores;
    detect_alexnet(m, cls_scores);
    std::vector<int> index;
    std::vector<float> score;
    print_topk(cls_scores, 3, index, score);

    //print_topk(cls_scores, 3);

     for (int i = 0; i < index.size(); i++)
    {
       cv::putText(m, labels[index[i]], cv::Point(50, 50 + 30 * i), cv::FONT_HERSHEY_SIMPLEX, 1.2, cv::Scalar(0, 100, 200), 2, 8);
    }

    cv::imshow("m", m);
    cv::imwrite("test_result.jpg", m);
    cv::waitKey(0);


    return 0;
}