jashliao 用 VC++ 實現 fanfuhan OpenCV 教學038 ~ opencv-038-拉普拉斯金字塔
jashliao 用 VC++ 實現 fanfuhan OpenCV 教學038 ~ opencv-038-拉普拉斯金字塔
資料來源: https://fanfuhan.github.io/
https://fanfuhan.github.io/2019/04/11/opencv-038/
GITHUB:https://github.com/jash-git/fanfuhan_ML_OpenCV
https://github.com/jash-git/jashliao-implements-FANFUHAN-OPENCV-with-VC
★前言:

★主題:
對輸入圖像實現金字塔的reduce操作就會生成不同分辨率的圖像、對這些圖像進行金字塔expand操作,然後使用reduce減去expand之後的結果就會得到圖像拉普拉斯金字塔圖像。
舉例如下:
輸入圖像G(0)
金字塔reduce操作生成G(1), G(2), G(3)
拉普拉斯金字塔:
L0 = G(0)-expand(G(1))
L1 = G (1)-expand(G(2))
L2 = G(2)–expand(G(3))
(G(0)減去expand(G(1))得到的結果就是兩次高斯模糊輸出的不同,所以L0稱為DOG(高斯不同)、它約等於LOG所以又稱為拉普拉斯金字塔。所以要求的圖像的拉普拉斯金字塔,首先要進行金字塔的reduce操作,然後在通過expand操作,最後相減得到拉普拉斯金字塔圖像。
★C++
// VC_FANFUHAN_OPENCV038.cpp : 定義主控台應用程式的進入點。
//
/*
// Debug | x32
通用屬性
| C/C++
| | 一般
| | 其他 Include 目錄 -> C:\opencv\build\include
|
| 連結器
| |一一般
| | 其他程式庫目錄 -> C:\opencv\build\x64\vc15\lib
|
| |一輸入
| | 其他相依性 -> opencv_world411d.lib;%(AdditionalDependencies)
// Releas | x64
組態屬性
| C/C++
| | 一般
| | 其他 Include 目錄 -> C:\opencv\build\include
|
| 連結器
| |一般
| | 其他程式庫目錄 -> C:\opencv\build\x64\vc15\lib
|
| |一輸入
| | 其他相依性 -> opencv_world411.lib;%(AdditionalDependencies)
*/
#include "stdafx.h"
#include <iostream>
#include <opencv2/opencv.hpp>
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
using namespace std;
using namespace cv;
void blur_demo(Mat &image, Mat &sum);
void edge_demo(Mat &image, Mat &sum);
int getblockSum(Mat &sum, int x1, int y1, int x2, int y2, int i);
void showHistogram(InputArray src, cv::String StrTitle);
void backProjection_demo(Mat &mat, Mat &model);
void blur3x3(Mat &src, Mat *det);
void add_salt_pepper_noise(Mat &image);
void add_gaussian_noise(Mat &image);
void USMImage(Mat src, Mat &usm, float fltPar);
void pyramid_up(Mat &image, vector<Mat> &pyramid_images, int level);
void pyramid_down(vector<Mat> &pyramid_images);
void laplaian_demo(vector<Mat> &pyramid_images, Mat &image);
void pause()
{
printf("Press Enter key to continue...");
fgetc(stdin);
}
int main()
{
Mat src = imread("../../images/test.png");
if (src.empty())
{
cout << "could not load image.." << endl;
pause();
return -1;
}
else
{
imshow("input_src", src);
showHistogram(src, "Histogram_input_src");
vector<Mat> p_images;
pyramid_up(src, p_images, 2);
laplaian_demo(p_images, src);
cout << "p_images size is " << p_images.size() << endl;
waitKey(0);
return 0;
}
return 0;
}
void laplaian_demo(vector<Mat> &pyramid_images, Mat &image)//拉普拉斯金字塔
{
for (int i = pyramid_images.size() - 1; i > -1; --i)
{
Mat dst;
if (i - 1 < 0)
{
pyrUp(pyramid_images[i], dst, image.size());
subtract(image, dst, dst);//圖像相減
dst = dst + Scalar(127, 127, 127); //调亮度, 实际中不能这么用
imshow(format("laplaian_layer_%d", i), dst);
}
else
{
pyrUp(pyramid_images[i], dst, pyramid_images[i - 1].size());
subtract(pyramid_images[i - 1], dst, dst);//圖像相減
dst = dst + Scalar(127, 127, 127); //調亮度, 实际中不能这么用
imshow(format("laplaian_layer_%d", i), dst);
}
}
}
void pyramid_down(vector<Mat> &pyramid_images)//高斯金字塔01
{
for (int i = pyramid_images.size() - 1; i > -1; --i) {
Mat dst;
/*
pyrUp(tmp, dst, Size(tmp.cols * 2, tmp.rows * 2))
tmp: 當前影象, 初始化為原影象 src 。
dst : 目的影象(顯示影象,為輸入影象的兩倍)
Size(tmp.cols * 2, tmp.rows * 2) : 目的影象大小, 既然我們是向上取樣, pyrUp 期待一個兩倍於輸入影象(tmp)的大小。
*/
pyrUp(pyramid_images[i], dst);
imshow(format("pyramid_down_%d", i), dst);
}
}
void pyramid_up(Mat &image, vector<Mat> &pyramid_images, int level)//高斯金字塔02
{
Mat temp = image.clone();
Mat dst;
for (int i = 0; i < level; ++i)
{
/*
pyrDown( tmp, dst, Size( tmp.cols/2, tmp.rows/2 ))
tmp: 當前影象, 初始化為原影象 src 。
dst: 目的影象( 顯示影象,為輸入影象的一半)
Size( tmp.cols/2, tmp.rows/2 ) :目的影象大小, 既然我們是向下取樣, pyrDown 期待一個一半於輸入影象( tmp)的大小。
注意輸入影象的大小(在兩個方向)必須是2的冥,否則,將會顯示錯誤。
最後,將輸入影象 tmp 更新為當前顯示影象, 這樣後續操作將作用於更新後的影象。
tmp = dst;
*/
pyrDown(temp, dst);
imshow(format("pyramid_up_%d", i), dst);
temp = dst.clone();
pyramid_images.push_back(temp);
}
}
void USMImage(Mat src, Mat &usm, float fltPar)//圖像銳化增强演算法(USM)
{
Mat blur_img;
/*
USM銳化公式表示如下:
(源圖像– w*高斯模糊)/(1-w);其中w表示權重(0.1~0.9),默認為0.6
OpenCV中的代碼實現步驟
– 高斯模糊
– 權重疊加
– 輸出結果
*/
GaussianBlur(src, blur_img, Size(0, 0), 25);
addWeighted(src, (1 + fltPar), blur_img, (fltPar*-1), 0, usm);//原圖 : 模糊圖片= 1.5 : -0.5 的比例進行混合
imshow("usm", usm);
showHistogram(usm, "Histogram_input_usm");
}
void blur_demo(Mat &image, Mat &sum)
{
int w = image.cols;
int h = image.rows;
Mat result = Mat::zeros(image.size(), image.type());
int x2 = 0, y2 = 0;
int x1 = 0, y1 = 0;
int ksize = 5;
int radius = ksize / 2;
int ch = image.channels();
int cx = 0, cy = 0;
for (int row = 0; row < h + radius; row++) {
y2 = (row + 1)>h ? h : (row + 1);
y1 = (row - ksize) < 0 ? 0 : (row - ksize);
for (int col = 0; col < w + radius; col++) {
x2 = (col + 1)>w ? w : (col + 1);
x1 = (col - ksize) < 0 ? 0 : (col - ksize);
cx = (col - radius) < 0 ? 0 : col - radius;
cy = (row - radius) < 0 ? 0 : row - radius;
int num = (x2 - x1)*(y2 - y1);
for (int i = 0; i < ch; i++) {
// 积分图查找和表,计算卷积
int s = getblockSum(sum, x1, y1, x2, y2, i);
result.at<Vec3b>(cy, cx)[i] = saturate_cast<uchar>(s / num);
}
}
}
imshow("blur_demo", result);
}
/**
* 3x3 sobel 垂直边缘检测演示
*/
void edge_demo(Mat &image, Mat &sum)
{
int w = image.cols;
int h = image.rows;
Mat result = Mat::zeros(image.size(), CV_32SC3);
int x2 = 0, y2 = 0;
int x1 = 0, y1 = 0;
int ksize = 3; // 算子大小,可以修改,越大边缘效应越明显
int radius = ksize / 2;
int ch = image.channels();
int cx = 0, cy = 0;
for (int row = 0; row < h + radius; row++) {
y2 = (row + 1)>h ? h : (row + 1);
y1 = (row - ksize) < 0 ? 0 : (row - ksize);
for (int col = 0; col < w + radius; col++) {
x2 = (col + 1)>w ? w : (col + 1);
x1 = (col - ksize) < 0 ? 0 : (col - ksize);
cx = (col - radius) < 0 ? 0 : col - radius;
cy = (row - radius) < 0 ? 0 : row - radius;
int num = (x2 - x1)*(y2 - y1);
for (int i = 0; i < ch; i++) {
// 积分图查找和表,计算卷积
int s1 = getblockSum(sum, x1, y1, cx, y2, i);
int s2 = getblockSum(sum, cx, y1, x2, y2, i);
result.at<Vec3i>(cy, cx)[i] = saturate_cast<int>(s2 - s1);
}
}
}
Mat dst, gray;
convertScaleAbs(result, dst);
normalize(dst, dst, 0, 255, NORM_MINMAX);
cvtColor(dst, gray, COLOR_BGR2GRAY);
imshow("edge_demo", gray);
}
int getblockSum(Mat &sum, int x1, int y1, int x2, int y2, int i) {
int tl = sum.at<Vec3i>(y1, x1)[i];
int tr = sum.at<Vec3i>(y2, x1)[i];
int bl = sum.at<Vec3i>(y1, x2)[i];
int br = sum.at<Vec3i>(y2, x2)[i];
int s = (br - bl - tr + tl);
return s;
}
void add_gaussian_noise(Mat &image)//高斯雜訊
{
Mat noise = Mat::zeros(image.size(), image.type());
// 产生高斯噪声
randn(noise, (15, 15, 15), (30, 30, 30));
Mat dst;
add(image, noise, dst);
image = dst.clone();//dst.copyTo(image);//圖像複製
//imshow("gaussian_noise", dst);
}
void add_salt_pepper_noise(Mat &image)//白雜訊
{
// 随机数产生器
RNG rng(12345);
for (int i = 0; i < 1000; ++i) {
int x = rng.uniform(0, image.rows);
int y = rng.uniform(0, image.cols);
if (i % 2 == 1) {
image.at<Vec3b>(y, x) = Vec3b(255, 255, 255);
}
else {
image.at<Vec3b>(y, x) = Vec3b(0, 0, 0);
}
}
//imshow("saltp_epper", image);
}
void blur3x3(Mat &src, Mat *det)
{
// 3x3 均值模糊,自定义版本实现
for (int row = 1; row < src.rows - 1; row++) {
for (int col = 1; col < src.cols - 1; col++) {
Vec3b p1 = src.at<Vec3b>(row - 1, col - 1);
Vec3b p2 = src.at<Vec3b>(row - 1, col);
Vec3b p3 = src.at<Vec3b>(row - 1, col + 1);
Vec3b p4 = src.at<Vec3b>(row, col - 1);
Vec3b p5 = src.at<Vec3b>(row, col);
Vec3b p6 = src.at<Vec3b>(row, col + 1);
Vec3b p7 = src.at<Vec3b>(row + 1, col - 1);
Vec3b p8 = src.at<Vec3b>(row + 1, col);
Vec3b p9 = src.at<Vec3b>(row + 1, col + 1);
int b = p1[0] + p2[0] + p3[0] + p4[0] + p5[0] + p6[0] + p7[0] + p8[0] + p9[0];
int g = p1[1] + p2[1] + p3[1] + p4[1] + p5[1] + p6[1] + p7[1] + p8[1] + p9[1];
int r = p1[2] + p2[2] + p3[2] + p4[2] + p5[2] + p6[2] + p7[2] + p8[2] + p9[2];
det->at<Vec3b>(row, col)[0] = saturate_cast<uchar>(b / 9);
det->at<Vec3b>(row, col)[1] = saturate_cast<uchar>(g / 9);
det->at<Vec3b>(row, col)[2] = saturate_cast<uchar>(r / 9);
}
}
}
void backProjection_demo(Mat &image, Mat &model)//反向投影
{
Mat image_hsv, model_hsv;
cvtColor(image, image_hsv, COLOR_BGR2HSV);//彩色轉HSV
cvtColor(model, model_hsv, COLOR_BGR2HSV);
// 定义直方图参数与属性
int h_bins = 32, s_bins = 32;
int histSize[] = { h_bins, s_bins };//要切分的像素強度值範圍,預設為256。每個channel皆可指定一個範圍。例如,[32,32,32] 表示RGB三個channels皆切分為32區段
float h_ranges[] = { 0, 180 }, s_ranges[] = { 0, 256 };
const float* ranges[] = { h_ranges, s_ranges };
int channels[] = { 0, 1 };
Mat roiHist;//計算ROI的直方圖
calcHist(&model_hsv, 1, channels, Mat(), roiHist, 2, histSize, ranges);
normalize(roiHist, roiHist, 0, 255, NORM_MINMAX, -1, Mat());
Mat roiproj, backproj;
calcBackProject(&image_hsv, 1, channels, roiHist, roiproj, ranges);//使用反向投影 產生ROI(前景)的mask
bitwise_not(roiproj, backproj);//產生背景的mask
imshow("ROIProj", roiproj);
imshow("BackProj", backproj);
}
void showHistogram(InputArray src, cv::String StrTitle)//直方圖
{
bool blnGray = false;
if (src.channels() == 1)
{
blnGray = true;
}
// 三通道/單通道 直方圖 紀錄陣列
vector<Mat> bgr_plane;
vector<Mat> gray_plane;
// 定义参数变量
const int channels[1] = { 0 };
const int bins[1] = { 256 };
float hranges[2] = { 0, 255 };
const float *ranges[1] = { hranges };
Mat b_hist, g_hist, r_hist, hist;
// 计算三通道直方图
/*
void calcHist( const Mat* images, int nimages,const int* channels, InputArray mask,OutputArray hist, int dims, const int* histSize,const float** ranges, bool uniform=true, bool accumulate=false );
1.輸入的圖像數組
2.輸入數組的個數
3.通道數
4.掩碼
5.直方圖
6.直方圖維度
7.直方圖每個維度的尺寸數組
8.每一維數組的範圍
9.直方圖是否是均勻
10.配置階段不清零
*/
if (blnGray)
{
split(src, gray_plane);
calcHist(&gray_plane[0], 1, 0, Mat(), hist, 1, bins, ranges);
}
else
{
split(src, bgr_plane);
calcHist(&bgr_plane[0], 1, 0, Mat(), b_hist, 1, bins, ranges);
calcHist(&bgr_plane[1], 1, 0, Mat(), g_hist, 1, bins, ranges);
calcHist(&bgr_plane[2], 1, 0, Mat(), r_hist, 1, bins, ranges);
}
/*
* 显示直方图
*/
int hist_w = 512;
int hist_h = 400;
int bin_w = cvRound((double)hist_w / bins[0]);
Mat histImage = Mat::zeros(hist_h, hist_w, CV_8UC3);
// 归一化直方图数据
if (blnGray)
{
normalize(hist, hist, 0, histImage.rows, NORM_MINMAX, -1);
}
else
{
normalize(b_hist, b_hist, 0, histImage.rows, NORM_MINMAX, -1);
normalize(g_hist, g_hist, 0, histImage.rows, NORM_MINMAX, -1);
normalize(r_hist, r_hist, 0, histImage.rows, NORM_MINMAX, -1);
}
// 绘制直方图曲线
for (int i = 1; i < bins[0]; ++i)
{
if (blnGray)
{
line(histImage, Point(bin_w * (i - 1), hist_h - cvRound(hist.at<float>(i - 1))),
Point(bin_w * (i), hist_h - cvRound(hist.at<float>(i))), Scalar(255, 255, 255),
2, 8, 0);
}
else
{
line(histImage, Point(bin_w * (i - 1), hist_h - cvRound(b_hist.at<float>(i - 1))),
Point(bin_w * (i), hist_h - cvRound(b_hist.at<float>(i))), Scalar(255, 0, 0),
2, 8, 0);
line(histImage, Point(bin_w * (i - 1), hist_h - cvRound(g_hist.at<float>(i - 1))),
Point(bin_w * (i), hist_h - cvRound(g_hist.at<float>(i))), Scalar(0, 255, 0),
2, 8, 0);
line(histImage, Point(bin_w * (i - 1), hist_h - cvRound(r_hist.at<float>(i - 1))),
Point(bin_w * (i), hist_h - cvRound(r_hist.at<float>(i))), Scalar(0, 0, 255),
2, 8, 0);
}
}
imshow(StrTitle, histImage);
}
★Python
import cv2 as cv
import numpy as np
def laplaian_demo(pyramid_images):
level = len(pyramid_images)
for i in range(level-1, -1, -1):
if (i-1) < 0:
h, w = src.shape[:2]
expand = cv.pyrUp(pyramid_images[i], dstsize=(w, h))
lpls = cv.subtract(src, expand) + 127
cv.imshow("lpls_" + str(i), lpls)
else:
h, w = pyramid_images[i-1].shape[:2]
expand = cv.pyrUp(pyramid_images[i], dstsize=(w, h))
lpls = cv.subtract(pyramid_images[i-1], expand) + 127
cv.imshow("lpls_"+str(i), lpls)
def pyramid_up(image, level=3):
temp = image.copy()
# cv.imshow("input", image)
pyramid_images = []
for i in range(level):
dst = cv.pyrDown(temp)
pyramid_images.append(dst)
# cv.imshow("pyramid_up_" + str(i), dst)
temp = dst.copy()
return pyramid_images
src = cv.imread("D:/images/master.jpg")
cv.namedWindow("input", cv.WINDOW_AUTOSIZE)
cv.imshow("input", src)
# pyramid_up(src)
laplaian_demo(pyramid_up(src))
cv.waitKey(0)
cv.destroyAllWindows()
★結果圖:

★延伸說明/重點回顧: