OpenCV背景虛化(前篇)
阿新 • • 發佈:2019-02-01
最近剛接到這個東西,心想不是太難,前後做了幾種方案。
首先想到的方案一:
摳圖得到影象的前景區域,對背景使用高斯模糊,然後將原圖前景區域疊加到第二步得到的圖層對應區域。
第一步摳圖我使用的是圖割演算法,因為手上有現成的程式,當然還有其他許多摳圖演算法,點選這裡來自於這篇部落格開始跳轉
然後模糊的話最好使用一些保邊模糊的濾波器,我以前就接觸過雙邊濾波以及引導濾波器,上面那篇文章還提到了Domain Transform filter
原圖如下:
其實後面背景已經很模糊了,這是液晶透鏡拍攝出來的影象,但是合作方覺得應該模糊量更大,其實以前是可以直接就拍出來的,後面有一些原因引數什麼的我也不怎麼會弄。
完整工程重點內容
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include <iostream>
using namespace std;
using namespace cv;
static void help()
{
cout << "\nThis program demonstrates GrabCut segmentation -- select an object in a region\n"
"and then grabcut will attempt to segment it out.\n"
"Call:\n"
"./grabcut <image_name>\n"
"\nSelect a rectangular area around the object you want to segment\n" <<
"\nHot keys: \n"
"\tESC - quit the program\n"
"\tr - restore the original image\n"
"\tn - next iteration\n"
"\n"
"\tleft mouse button - set rectangle\n"
"\n"
"\tCTRL+left mouse button - set GC_BGD pixels\n"
"\tSHIFT+left mouse button - set CG_FGD pixels\n"
"\n"
"\tCTRL+right mouse button - set GC_PR_BGD pixels\n"
"\tSHIFT+right mouse button - set CG_PR_FGD pixels\n" << endl;
}
const Scalar RED = Scalar(0,0,255);
const Scalar PINK = Scalar(230,130,255);
const Scalar BLUE = Scalar(255,0,0);
const Scalar LIGHTBLUE = Scalar(255,255,160);
const Scalar GREEN = Scalar(0,255,0);
const int BGD_KEY = CV_EVENT_FLAG_CTRLKEY; //Ctrl鍵
const int FGD_KEY = CV_EVENT_FLAG_SHIFTKEY; //Shift鍵
static void getBinMask( const Mat& comMask, Mat& binMask )
{
if( comMask.empty() || comMask.type()!=CV_8UC1 )
CV_Error( CV_StsBadArg, "comMask is empty or has incorrect type (not CV_8UC1)" );
if( binMask.empty() || binMask.rows!=comMask.rows || binMask.cols!=comMask.cols )
binMask.create( comMask.size(), CV_8UC1 );
binMask = comMask & 1; //得到mask的最低位,實際上是隻保留確定的或者有可能的前景點當做mask
}
class GCApplication
{
public:
enum{ NOT_SET = 0, IN_PROCESS = 1, SET = 2 };
static const int radius = 2;
static const int thickness = -1;
void reset();
void setImageAndWinName( const Mat& _image, const string& _winName );
void showImage() const;
void mouseClick( int event, int x, int y, int flags, void* param );
int nextIter();
int getIterCount() const { return iterCount; }
private:
void setRectInMask();
void setLblsInMask( int flags, Point p, bool isPr );
const string* winName;
const Mat* image;
Mat mask;
Mat bgdModel, fgdModel;
uchar rectState, lblsState, prLblsState;
bool isInitialized;
Rect rect;
vector<Point> fgdPxls, bgdPxls, prFgdPxls, prBgdPxls;
int iterCount;
};
/*給類的變數賦值*/
void GCApplication::reset()
{
if( !mask.empty() )
mask.setTo(Scalar::all(GC_BGD));
bgdPxls.clear(); fgdPxls.clear();
prBgdPxls.clear(); prFgdPxls.clear();
isInitialized = false;
rectState = NOT_SET; //NOT_SET == 0
lblsState = NOT_SET;
prLblsState = NOT_SET;
iterCount = 0;
}
/*給類的成員變數賦值而已*/
void GCApplication::setImageAndWinName( const Mat& _image, const string& _winName )
{
if( _image.empty() || _winName.empty() )
return;
image = &_image;
winName = &_winName;
mask.create( image->size(), CV_8UC1);
reset();
}
/*顯示4個點,一個矩形和影象內容,因為後面的步驟很多地方都要用到這個函式,所以單獨拿出來*/
void GCApplication::showImage() const
{
if( image->empty() || winName->empty() )
return;
Mat res;
Mat binMask;
if( !isInitialized )
image->copyTo( res );
else
{
getBinMask( mask, binMask );
image->copyTo( res, binMask ); //按照最低位是0還是1來複制,只保留跟前景有關的影象,比如說可能的前景,可能的背景
}
vector<Point>::const_iterator it;
/*下面4句程式碼是將選中的4個點用不同的顏色顯示出來*/
for( it = bgdPxls.begin(); it != bgdPxls.end(); ++it ) //迭代器可以看成是一個指標
circle( res, *it, radius, BLUE, thickness );
for( it = fgdPxls.begin(); it != fgdPxls.end(); ++it ) //確定的前景用紅色表示
circle( res, *it, radius, RED, thickness );
for( it = prBgdPxls.begin(); it != prBgdPxls.end(); ++it )
circle( res, *it, radius, LIGHTBLUE, thickness );
for( it = prFgdPxls.begin(); it != prFgdPxls.end(); ++it )
circle( res, *it, radius, PINK, thickness );
/*畫矩形*/
if( rectState == IN_PROCESS || rectState == SET )
rectangle( res, Point( rect.x, rect.y ), Point(rect.x + rect.width, rect.y + rect.height ), (0,0,0), 2);
//這裡的矩形框顏色本來是綠色的,我改為(0,0,0)黑色
imshow( *winName, res );
imwrite("C:\\Users\\ltc\\Desktop\\testdata_3.jpg",res);
}
/*該步驟完成後,mask影象中rect內部是3,外面全是0*/
void GCApplication::setRectInMask()
{
assert( !mask.empty() );
mask.setTo( GC_BGD ); //GC_BGD == 0
rect.x = max(0, rect.x);
rect.y = max(0, rect.y);
rect.width = min(rect.width, image->cols-rect.x);
rect.height = min(rect.height, image->rows-rect.y);
(mask(rect)).setTo( Scalar(GC_PR_FGD) ); //GC_PR_FGD == 3,矩形內部,為可能的前景點
}
void GCApplication::setLblsInMask( int flags, Point p, bool isPr )
{
vector<Point> *bpxls, *fpxls;
uchar bvalue, fvalue;
if( !isPr ) //確定的點
{
bpxls = &bgdPxls;
fpxls = &fgdPxls;
bvalue = GC_BGD; //0
fvalue = GC_FGD; //1
}
else //概率點
{
bpxls = &prBgdPxls;
fpxls = &prFgdPxls;
bvalue = GC_PR_BGD; //2
fvalue = GC_PR_FGD; //3
}
if( flags & BGD_KEY )
{
bpxls->push_back(p);
circle( mask, p, radius, bvalue, thickness ); //該點處為2
}
if( flags & FGD_KEY )
{
fpxls->push_back(p);
circle( mask, p, radius, fvalue, thickness ); //該點處為3
}
}
/*滑鼠響應函式,引數flags為CV_EVENT_FLAG的組合*/
void GCApplication::mouseClick( int event, int x, int y, int flags, void* )
{
// TODO add bad args check
switch( event )
{
case CV_EVENT_LBUTTONDOWN: // set rect or GC_BGD(GC_FGD) labels
{
bool isb = (flags & BGD_KEY) != 0,
isf = (flags & FGD_KEY) != 0;
if( rectState == NOT_SET && !isb && !isf )//只有左鍵按下時
{
rectState = IN_PROCESS; //表示正在畫矩形
rect = Rect( x, y, 1, 1 );
}
if ( (isb || isf) && rectState == SET ) //按下了alt鍵或者shift鍵,且畫好了矩形,表示正在畫前景背景點
lblsState = IN_PROCESS;
}
break;
case CV_EVENT_RBUTTONDOWN: // set GC_PR_BGD(GC_PR_FGD) labels
{
bool isb = (flags & BGD_KEY) != 0,
isf = (flags & FGD_KEY) != 0;
if ( (isb || isf) && rectState == SET ) //正在畫可能的前景背景點
prLblsState = IN_PROCESS;
}
break;
case CV_EVENT_LBUTTONUP:
if( rectState == IN_PROCESS )
{
rect = Rect( Point(rect.x, rect.y), Point(x,y) ); //矩形結束
rectState = SET;
setRectInMask();
assert( bgdPxls.empty() && fgdPxls.empty() && prBgdPxls.empty() && prFgdPxls.empty() );
showImage();
}
if( lblsState == IN_PROCESS ) //已畫了前後景點
{
setLblsInMask(flags, Point(x,y), false); //畫出前景點
lblsState = SET;
showImage();
}
break;
case CV_EVENT_RBUTTONUP:
if( prLblsState == IN_PROCESS )
{
setLblsInMask(flags, Point(x,y), true); //畫出背景點
prLblsState = SET;
showImage();
}
break;
case CV_EVENT_MOUSEMOVE:
if( rectState == IN_PROCESS )
{
rect = Rect( Point(rect.x, rect.y), Point(x,y) );
assert( bgdPxls.empty() && fgdPxls.empty() && prBgdPxls.empty() && prFgdPxls.empty() );
showImage(); //不斷的顯示圖片
}
else if( lblsState == IN_PROCESS )
{
setLblsInMask(flags, Point(x,y), false);
showImage();
}
else if( prLblsState == IN_PROCESS )
{
setLblsInMask(flags, Point(x,y), true);
showImage();
}
break;
}
}
/*該函式進行grabcut演算法,並且返回演算法執行迭代的次數*/
int GCApplication::nextIter()
{
if( isInitialized )
//使用grab演算法進行一次迭代,引數2為mask,裡面存的mask位是:矩形內部除掉那些可能是背景或者已經確定是背景後的所有的點,且mask同時也為輸出
//儲存的是分割後的前景影象
grabCut( *image, mask, rect, bgdModel, fgdModel, 1 );
else
{
if( rectState != SET )
return iterCount;
if( lblsState == SET || prLblsState == SET )
grabCut( *image, mask, rect, bgdModel, fgdModel, 1, GC_INIT_WITH_MASK );
else
grabCut( *image, mask, rect, bgdModel, fgdModel, 1, GC_INIT_WITH_RECT );
isInitialized = true;
}
iterCount++;
bgdPxls.clear(); fgdPxls.clear();
prBgdPxls.clear(); prFgdPxls.clear();
return iterCount;
}
GCApplication gcapp;
static void on_mouse( int event, int x, int y, int flags, void* param )
{
gcapp.mouseClick( event, x, y, flags, param );
}
int main( int argc, char** argv )
{
string filename = "C:\\Users\\ltc\\Desktop\\data3\\taowa.jpg";
Mat image = imread( filename, 1 );
if( image.empty() )
{
cout << "\n Durn, couldn't read image filename " << filename << endl;
return 1;
}
help();
const string winName = "image";
cvNamedWindow( winName.c_str(), CV_WINDOW_NORMAL );
cvSetMouseCallback( winName.c_str(), on_mouse, 0 );
gcapp.setImageAndWinName( image, winName );
gcapp.showImage();
for(;;)
{
int c = cvWaitKey(0);
switch( (char) c )
{
case '\x1b':
cout << "Exiting ..." << endl;
goto exit_main;
case 'r':
cout << endl;
gcapp.reset();
gcapp.showImage();
break;
case 'n':
int iterCount = gcapp.getIterCount();
cout << "<" << iterCount << "... ";
int newIterCount = gcapp.nextIter();
if( newIterCount > iterCount )
{
gcapp.showImage();
cout << iterCount << ">" << endl;
}
else
cout << "rect must be determined>" << endl;
break;
}
}
exit_main:
cvDestroyWindow( winName.c_str() );
return 0;
}
該有的註釋都有,然後如何操作也在help資訊裡可以看到,基本上就是框個框畫幾筆然後迭代幾次就可以了。
現在肯定有很多更好的影象分割方法,任務緊,就沒時間去折騰了。
效果如下:
然後相減得到背景,對背景進行高斯模糊:
高斯模糊滑動條控制如下:可以選擇一個你覺得合適的模糊
#include<opencv2/core/core.hpp>
#include<opencv2/highgui/highgui.hpp>
#include<opencv2/imgproc/imgproc.hpp>
#include<iostream>
#include<cstdlib>
#include<math.h>
using namespace cv;
using namespace std;
int x=0;
int y=0;
int size=3;
Mat scrImage;
Mat tempImage;
void onTrack(int, void*)
{
scrImage = tempImage.clone();
GaussianBlur(scrImage, scrImage, Size(2*size+1, 2*size+1), x, y);
imshow("【原圖】", scrImage);
}
int main()
{
scrImage = imread("C:\\Users\\ltc\\Desktop\\data3\\taowa.jpg");
tempImage = scrImage.clone();
namedWindow("【原圖】",WINDOW_NORMAL);
imshow("【原圖】", scrImage);
createTrackbar("gaussion x", "【原圖】", &x, 100, onTrack);
createTrackbar("gaussion y", "【原圖】", &y, 100, onTrack);
createTrackbar("gaussion size", "【原圖】", &size, 100, onTrack);
waitKey();
return 0;
}
最後結合的話我是直接相加,效果如下:
可以看到馬周身有很大一圈白色邊緣。
後面我對原圖直接模糊,然後把摳出來的馬copyTo貼上去。
最後效果如下:
可以看到馬的周身有很多黑色畫素冒出來。
後面我用
#include<iostream>
#include<opencv2/opencv.hpp>
using namespace std;
using namespace cv;
bool g_bDrawing = false;
Point g_CurrPoint, g_OrgPoint;
int g_nThick = 5, g_nBlue = 255, g_nGreen = 255, g_nRed = 0;
int g_nImageOneValue = 49;
Mat srcImage;
Mat grayImage;
Mat maskImage;
/*注意:不能在毀掉函式中寫入未初始化的矩陣類,所以需要用時,需要寫一個標誌位,然後再在while(1)迴圈內使用*/
void onMouse(int event, int x, int y, int flag, void *param)
{
Mat &img = *(cv::Mat*)param;
switch (event)
{
//移動滑鼠的時候
case CV_EVENT_MOUSEMOVE:
{
g_OrgPoint = g_CurrPoint;
g_CurrPoint = Point(x, y);
if (g_bDrawing == 1)
{
line(srcImage, g_CurrPoint, g_OrgPoint, Scalar(g_nBlue, g_nGreen, g_nRed), g_nThick);
imshow("【滑鼠事件視窗】", srcImage);
//在掩膜圖上進行顯示
line(maskImage, g_CurrPoint, g_OrgPoint, Scalar(g_nBlue, g_nGreen, g_nRed), g_nThick);
imshow("【掩膜影象】", maskImage);
}
}
break;
//點選滑鼠左鍵時
case CV_EVENT_LBUTTONDOWN:
{
g_bDrawing = true;
g_OrgPoint = Point(x, y);
g_CurrPoint = g_OrgPoint;
}
break;
//鬆開滑鼠左鍵時
case CV_EVENT_LBUTTONUP:
{
g_bDrawing = false;
}
break;
}
}
int main()
{
Mat tempImage;
RNG &rng = theRNG();
srcImage = imread("C:\\Users\\ltc\\Desktop\\data3\\dstbig.jpg");
resize(srcImage,srcImage,Size(640,480));
//用一個變數來儲存原影象
Mat g_srcImage;
srcImage.copyTo(g_srcImage);
//為掩膜圖 分配空間
maskImage.create(srcImage.size(), CV_8UC1);
maskImage = Scalar::all(0);
namedWindow("【滑鼠事件視窗】",WINDOW_NORMAL);
setMouseCallback("【滑鼠事件視窗】", onMouse, 0);
namedWindow("【滾動條視窗】", 0);
createTrackbar("thick", "【滾動條視窗】", &g_nThick, 100, 0);
createTrackbar("Blue", "【滾動條視窗】", &g_nBlue, 255, 0);
createTrackbar("Green", "【滾動條視窗】", &g_nGreen, 255, 0);
createTrackbar("Red", "【滾動條視窗】", &g_nRed, 255, 0);
char key;
while (1)
{
imshow("【滑鼠事件視窗】", srcImage);
key = waitKey();
if (key == 27)
break;
//如果檢測到 鍵值是1 則恢復原圖
if (key == '1')
{
g_srcImage.copyTo(srcImage);
maskImage = Scalar::all(0);
imshow("【滑鼠事件視窗】", srcImage);
}
//如果檢測到空格 則開始執行影象修復
Mat dstImage;
dstImage.create(srcImage.size(), srcImage.type());
if (key == ' ')
{
inpaint(srcImage, maskImage, dstImage, 3, INPAINT_TELEA);
imshow("【修補後的影象】", dstImage);
}
}
return 0;
}
下面這個程式碼對馬的周身(針對黑色畫素情況)進行一個修補,這是無奈的辦法,我也不想手動。
最終效果如下:
其實我也用Imageshop這個軟體手動磨皮,發現效果和這個差不多,先就這樣,交給老師,老師
覺得還不夠,老師希望恐龍和背景的模糊層次能夠分開。基於我們的深度圖來做。
放在後面寫了。。。。