native.cpp

//
// Created by fujiayi on 2020/7/5.
//

#include "native.h"
#include "ocr_ppredictor.h"
#include <string>
#include <algorithm>
#include <paddle_api.h>

static paddle::lite_api::PowerMode str_to_cpu_mode(const std::string &cpu_mode);

extern "C"
JNIEXPORT jlong JNICALL
Java_com_baidu_paddle_lite_demo_ocr_OCRPredictorNative_init(JNIEnv *env, jobject thiz,
                                                            jstring j_det_model_path,
                                                            jstring j_rec_model_path,
                                                            jint j_thread_num,
                                                            jstring j_cpu_mode) {
    std::string det_model_path = jstring_to_cpp_string(env, j_det_model_path);
    std::string rec_model_path = jstring_to_cpp_string(env, j_rec_model_path);
    int thread_num = j_thread_num;
    std::string cpu_mode = jstring_to_cpp_string(env, j_cpu_mode);
    ppredictor::OCR_Config conf;
    conf.thread_num = thread_num;
    conf.mode = str_to_cpu_mode(cpu_mode);
    ppredictor::OCR_PPredictor *orc_predictor = new ppredictor::OCR_PPredictor{conf};
    orc_predictor->init_from_file(det_model_path, rec_model_path);
    return reinterpret_cast<jlong>(orc_predictor);
}

/**
 * "LITE_POWER_HIGH" convert to paddle::lite_api::LITE_POWER_HIGH
 * @param cpu_mode
 * @return
 */
static paddle::lite_api::PowerMode str_to_cpu_mode(const std::string &cpu_mode) {
    static std::map<std::string, paddle::lite_api::PowerMode> cpu_mode_map{
        {"LITE_POWER_HIGH",      paddle::lite_api::LITE_POWER_HIGH},
        {"LITE_POWER_LOW",       paddle::lite_api::LITE_POWER_HIGH},
        {"LITE_POWER_FULL",      paddle::lite_api::LITE_POWER_FULL},
        {"LITE_POWER_NO_BIND",   paddle::lite_api::LITE_POWER_NO_BIND},
        {"LITE_POWER_RAND_HIGH", paddle::lite_api::LITE_POWER_RAND_HIGH},
        {"LITE_POWER_RAND_LOW",  paddle::lite_api::LITE_POWER_RAND_LOW}
    };
    std::string upper_key;
    std::transform(cpu_mode.cbegin(), cpu_mode.cend(), upper_key.begin(), ::toupper);
    auto index = cpu_mode_map.find(upper_key);
    if (index == cpu_mode_map.end()) {
        LOGE("cpu_mode not found %s", upper_key.c_str());
        return paddle::lite_api::LITE_POWER_HIGH;
    } else {
        return index->second;
    }

}

extern "C"
JNIEXPORT jfloatArray JNICALL
Java_com_baidu_paddle_lite_demo_ocr_OCRPredictorNative_forward(JNIEnv *env, jobject thiz,
                                                               jlong java_pointer, jfloatArray buf,
                                                               jfloatArray ddims,
                                                               jobject original_image) {
    LOGI("begin to run native forward");
    if (java_pointer == 0) {
        LOGE("JAVA pointer is NULL");
        return cpp_array_to_jfloatarray(env, nullptr, 0);
    }
    cv::Mat origin = bitmap_to_cv_mat(env, original_image);
    if (origin.size == 0) {
        LOGE("origin bitmap cannot convert to CV Mat");
        return cpp_array_to_jfloatarray(env, nullptr, 0);
    }
    ppredictor::OCR_PPredictor *ppredictor = (ppredictor::OCR_PPredictor *) java_pointer;
    std::vector<float> dims_float_arr = jfloatarray_to_float_vector(env, ddims);
    std::vector<int64_t> dims_arr;
    dims_arr.resize(dims_float_arr.size());
    std::copy(dims_float_arr.cbegin(), dims_float_arr.cend(), dims_arr.begin());

    // 这里值有点大，就不调用jfloatarray_to_float_vector了
    int64_t buf_len = (int64_t) env->GetArrayLength(buf);
    jfloat *buf_data = env->GetFloatArrayElements(buf, JNI_FALSE);
    float *data = (jfloat *) buf_data;
    std::vector<ppredictor::OCRPredictResult> results = ppredictor->infer_ocr(dims_arr, data,
                                                                              buf_len,
                                                                              NET_OCR, origin);
    LOGI("infer_ocr finished with boxes %ld", results.size());
    // 这里将std::vector<ppredictor::OCRPredictResult> 序列化成 float数组，传输到java层再反序列化
    std::vector<float> float_arr;
    for (const ppredictor::OCRPredictResult &r :results) {
        float_arr.push_back(r.points.size());
        float_arr.push_back(r.word_index.size());
        float_arr.push_back(r.score);
        for (const std::vector<int> &point : r.points) {
            float_arr.push_back(point.at(0));
            float_arr.push_back(point.at(1));
        }
        for (int index: r.word_index) {
            float_arr.push_back(index);
        }
    }
    return cpp_array_to_jfloatarray(env, float_arr.data(), float_arr.size());
}

extern "C"
JNIEXPORT void JNICALL
Java_com_baidu_paddle_lite_demo_ocr_OCRPredictorNative_release(JNIEnv *env, jobject thiz,
                                                               jlong java_pointer){
    if (java_pointer == 0) {
        LOGE("JAVA pointer is NULL");
        return;
    }
    ppredictor::OCR_PPredictor *ppredictor = (ppredictor::OCR_PPredictor *) java_pointer;
    delete ppredictor;
}