OPENCV对于有alpha通道的透明背景图片的读取和图片叠加

来源：互联网发布：php 读取cer证书公钥编辑：程序博客网时间：2024/05/02 01:29

OPENCV对于有alpha通道的透明背景图片的读取和图片叠加

不过PS是通过在BMP文件格式后追加一个ALPHA数据来实现的，因为BMP本身不支持alpha，所以不能用常规的在程序中直接new bitmap来做。

要先提取追加的这段数据。

Mat inimg = imread("dog.png", CV_LOAD_IMAGE_UNCHANGED); // 读取透明通道// 输出RGBA数值cout << (int)inimg.at<Vec4b>(0,0)[0] << endl     << (int)inimg.at<Vec4b>(0,0)[1] << endl     << (int)inimg.at<Vec4b>(0,0)[2] << endl     << (int)inimg.at<Vec4b>(0,0)[3] << endl;

#include <vector>#include <stdio.h>#include <opencv2/opencv.hpp>using namespace cv;using namespace std;int cvAdd4cMat_q(cv::Mat &dst, cv::Mat &scr, double scale);int main(){char str[16];Mat img1 = imread("bk.jpg"), img2 = imread("img.png", -1);Mat img1_t1(img1, cvRect(0, 0, img2.cols, img2.rows));cvAdd4cMat_q(img1_t1,img2,1.0);imshow("final",img1);waitKey(0);return 0;}int cvAdd4cMat_q(cv::Mat &dst, cv::Mat &scr, double scale)  {  if (dst.channels() != 3 || scr.channels() != 4)  {  return true;  }  if (scale < 0.01)  return false;  std::vector<cv::Mat>scr_channels;  std::vector<cv::Mat>dstt_channels;  split(scr, scr_channels);  split(dst, dstt_channels);  CV_Assert(scr_channels.size() == 4 && dstt_channels.size() == 3);  if (scale < 1)  {  scr_channels[3] *= scale;  scale = 1;  }  for (int i = 0; i < 3; i++)  {  dstt_channels[i] = dstt_channels[i].mul(255.0 / scale - scr_channels[3], scale / 255.0);  dstt_channels[i] += scr_channels[i].mul(scr_channels[3], scale / 255.0);  }  merge(dstt_channels, dst);  return true;  }

阅读全文

0 0