CMSIS-NN 调通了~

下载地址:CMSIS-NN

由于是8位定点的推算算法,所以精度会差点,但是速度快啊,需要把图片存TF卡里,或者你自己开发驱动,我用的是STM32F769 DISCO.

关键代码:

int8_t NN_OpenReadFile(const char *BmpName)

{

  uint32_t size = 0;

  int32_t h_index = 0;

  int32_t w_index = 0;

  int32_t h_total = 0;

  int32_t w_total = 0;

  int32_t h_nn = 0;

  int32_t w_nn = 0;

  UINT BytesRead;

  FIL bmpfile;



  q7_t output_data[10]; /* 输出数据,分别代表{"Plane", "Car", "Bird", "Cat", "Deer", "Dog", "Frog", "Horse", "Ship", "Truck"} */



  int8_t max_ind = 0;

  int8_t max_val = -128;



  BmpHeader *pbmpheader = (BmpHeader *)aBuffer;



  /* 打开BMP文件 */

  f_open(&bmpfile, BmpName, FA_READ);



  /* 移动到文件头 */

  f_lseek(&bmpfile, 0);



  /* 读取头信息 */

  f_read(&bmpfile, &aBuffer, BITMAP_HEADER_SIZE, &BytesRead);



  /* 取出原图的长宽 */

  h_total = pbmpheader->h;

  w_total = pbmpheader->w;

  /* 计算出缩小比例 */

  h_nn = pbmpheader->h / 32;

  w_nn = pbmpheader->w / 32;



  /* 取出一次读出数量 */

  size = pbmpheader->w * (pbmpheader->bpp / 8) + ((pbmpheader->w * (pbmpheader->bpp / 8)) % 4);



  if (pbmpheader->bpp != 24)

  {

    return -1; /* 保存为24Bit图像吧. */

  }



  if (size > BITMAP_BUFFER_SIZE)

  {

    return -2; /* 图片太大,超过缓冲区大小. */

  }



  /* 偏移到图像内容,然后提取图像内容到32*32的范围内. */

  f_lseek(&bmpfile, pbmpheader->offset);

  for (h_index = 0; h_index < h_total; h_index++)

  {

    f_read(&bmpfile, &aBuffer, size, &BytesRead);

    if (h_index % h_nn == 0)

    {

      for (w_index = 0; w_index < w_total; w_index++)

      {

        if (w_index % w_nn == 0)

        {

          BmpBuffer[(h_index) / h_nn][w_index / w_nn][2] = aBuffer[3 * w_index];

          BmpBuffer[(h_index) / h_nn][w_index / w_nn][1] = aBuffer[3 * w_index + 1];

          BmpBuffer[(h_index) / h_nn][w_index / w_nn][0] = aBuffer[3 * w_index + 2];

        }

      }

    }

  }



  /* 关闭文件 */

  f_close(&bmpfile);



  /* 运行NN算法 */

  run_nn((q7_t *)BmpBuffer, output_data);

  arm_softmax_q7(output_data, IP1_OUT_DIM, output_data);



  /* 找出最可信结果 */

  for (int i = 0; i < 10; i++)

  {

    if (max_val < output_data[i])

    {

      max_val = output_data[i];

      max_ind = i;

    }

  }



  /* 返回可信结果 */

  return max_ind;

}

返回值如果是正,就是有结果,0 ~ 9分别对应"Plane", "Car", "Bird", "Cat", "Deer", "Dog", "Frog", "Horse", "Ship", "Truck"这么几种,推荐用Windows 10画图工具保存为24位BMP,最好的分辨率是32*32,如果不是32*32,则在程序里也有缩放,但是效果不太好,因为我是直接间隔抽取的,良好的缩放算法应该考虑颜色权重问题.