如何進行OpenCV imread 圖片讀取

如何進行OpenCV imread 圖片讀取，相信很多沒有經驗的人對此束手無策，為此本文總結了問題出現的原因和解決方法，通過這篇文章希望你能解決這個問題。

函數原型

            CV_EXPORTS_W Mat imread( const String& filename, int flags = IMREAD_COLOR );

參數說明

第一個參數是圖片路徑名稱，強烈建議使用/作為目錄的分割符號，例如

第二參數具有如下的值，說明了讀取過程中是否需要進行像素的操作，例如取值0，表示讀取過程中將像素轉換為灰度值，默認參數是1， 表示不改變原圖像的像素

enum ImreadModes {

       IMREAD_UNCHANGED            = -1, //!< If set, return the loaded p_w_picpath as is (with alpha channel, otherwise it gets cropped).

       IMREAD_GRAYSCALE            = 0,  //!< If set, always convert p_w_picpath to the single channel grayscale p_w_picpath.

       IMREAD_COLOR                = 1,  //!< If set, always convert p_w_picpath to the 3 channel BGR color p_w_picpath.

       IMREAD_ANYDEPTH             = 2,  //!< If set, return 16-bit/32-bit p_w_picpath when the input has the corresponding depth, otherwise convert it to 8-bit.

       IMREAD_ANYCOLOR             = 4,  //!< If set, the p_w_picpath is read in any possible color format.

       IMREAD_LOAD_GDAL            = 8,  //!< If set, use the gdal driver for loading the p_w_picpath.

       IMREAD_REDUCED_GRAYSCALE_2  = 16, //!< If set, always convert p_w_picpath to the single channel grayscale p_w_picpath and the p_w_picpath size reduced 1/2.

       IMREAD_REDUCED_COLOR_2      = 17, //!< If set, always convert p_w_picpath to the 3 channel BGR color p_w_picpath and the p_w_picpath size reduced 1/2.

       IMREAD_REDUCED_GRAYSCALE_4  = 32, //!< If set, always convert p_w_picpath to the single channel grayscale p_w_picpath and the p_w_picpath size reduced 1/4.

       IMREAD_REDUCED_COLOR_4      = 33, //!< If set, always convert p_w_picpath to the 3 channel BGR color p_w_picpath and the p_w_picpath size reduced 1/4.

       IMREAD_REDUCED_GRAYSCALE_8  = 64, //!< If set, always convert p_w_picpath to the single channel grayscale p_w_picpath and the p_w_picpath size reduced 1/8.

       IMREAD_REDUCED_COLOR_8      = 65, //!< If set, always convert p_w_picpath to the 3 channel BGR color p_w_picpath and the p_w_picpath size reduced 1/8.

       IMREAD_IGNORE_ORIENTATION   = 128 //!< If set, do not rotate the p_w_picpath according to EXIF's orientation flag.

     };

例子

#include "opencv2/opencv.hpp"

int main(int argc, char *argv[])

{

    cv::Mat srcImg = cv::imread("F:/test2.png", 1);

    return 0;

}

注意：

在進行圖像的灰度值處理之后，默認情況下， 不會進行圖像的直方圖進行圖像的增強，否則會出現運行異常

代碼

#include <opencv2/highgui/highgui.hpp>    

#include <opencv2/imgproc/imgproc.hpp>

#include <iostream>

using namespace cv;

int main(int argc, char *argv[])

{

  Mat p_w_picpath = imread("D:/20170601092226.png", 0);

  if (p_w_picpath.empty())

  {

    std::cout << "打開圖片失敗,請檢查" << std::endl;

    return -1;

  }

  imshow("原圖像", p_w_picpath);

  waitKey();

  return 0;

  Mat p_w_picpathRGB[3];

  split(p_w_picpath, p_w_picpathRGB);

  for (int i = 0; i < 3; i++)

  {

    equalizeHist(p_w_picpathRGB[i], p_w_picpathRGB[i]);

  }

  merge(p_w_picpathRGB, 3, p_w_picpath);

  imshow("直方圖均衡化圖像增強效果", p_w_picpath);

  waitKey();

  return 0;

}

看完上述內容，你們掌握如何進行OpenCV imread 圖片讀取的方法了嗎？如果還想學到更多技能或想了解更多相關內容，歡迎關注億速云行業資訊頻道，感謝各位的閱讀！