从字节数组创建hbitmap
问题描述：
我想将字节数组转换为hbitmap，反之亦然
我看到了功能
CreateDIBitmap();
StretchBlt();
但是图像质量有些令人不安.
请问有什么好方法.
i want to convert byte array to hbitmap and vice versa
i saw the function
CreateDIBitmap( );
StretchBlt( );
but image quality is some what disturbed.
wel is there any good way .
答
如果可能，请使用GDI plus.(它具有插值法)
您可以使用Bitmap类，然后使用LockBits函数，并将像素复制到其中.您还将从Bitmap类中获取本机位图句柄(使用GetHbitmap函数)..
Use GDI plus if possible.( it has interpolation)
You can use Bitmap class, then use LockBits function , and copy your pixels in to it. You will also get native bitmap handle from Bitmap class(use GetHbitmap function)..
#include "stdafx.h"
#include "Resample.h" // this is dll for resizing the image
class imageReader
{
public:
imageReader();
~imageReader();
HBITMAP readBuffer(char *buffer, HWND parentWindow, RECT rectDisp);
void renderImage(HBITMAP disimage);
private:
HWND parent;
RECT rect;
HBITMAP image;
};
imageReader::imageReader()
{
}
imageReader::~imageReader()
{
}
HBITMAP imageReader::readBuffer(char *buffer, HWND parentWindow, RECT rectDisp)
{
parent=parentWindow;
rect=rectDisp;
BITMAPFILEHEADER& bfh = (BITMAPFILEHEADER&)buffer[0];
BITMAPINFO& bi = (BITMAPINFO&)buffer[sizeof(BITMAPFILEHEADER)];
BITMAPINFOHEADER& bih = bi.bmiHeader;
char* bitmap = &buffer[bfh.bfOffBits];
HDC hdcW = GetDC(parent); // window's DC
image = CreateDIBitmap( hdcW, &bih, CBM_INIT, bitmap, &bi, DIB_RGB_COLORS );
image= CreateResampledBitmap(hdcW, image, rect.right-rect.left, rect.bottom-rect.top, STOCK_FILTER_BOX);
return image;
}
void imageReader::renderImage(HBITMAP disimage)
{
PAINTSTRUCT ps;
HDC hdc = BeginPaint(parent, &ps);
BITMAP bm;
HDC hdcMem = CreateCompatibleDC(hdc);
SelectObject(hdcMem, disimage);
GetObject(disimage, sizeof(bm), &bm);
BitBlt(hdc,rect.left, rect.top, bm.bmWidth, bm.bmHeight, hdcMem, 0, 0, SRCCOPY);
DeleteDC(hdcMem);
EndPaint( parent, &ps );
}
// example of implementation of above class
//imageReader imageobj;
// FILE* f = fopen( "C:\\test.bmp", "rb" ); if( f==0 ) return 1;
// fread( buf, 1,sizeof(buf), f );
// fclose(f);
//}
// WINDOWPLACEMENT lpwndpl2;
// GetWindowPlacement(hw,&lpwndpl2); //hw is handle to picture control where u want to render image
// RECT rectImage;
// rectImage.left=lpwndpl2.rcNormalPosition.left;
// rectImage.right=lpwndpl2.rcNormalPosition.right;
// rectImage.top=lpwndpl2.rcNormalPosition.top;
// rectImage.bottom=lpwndpl2.rcNormalPosition.bottom;
// HBITMAP hBitmap=imageobj.readBuffer(buf,hwparent,rectImage);//hwparent is handle to main dialog(parent)
/
//imageobj.renderImage(hBitmap);
//InvalidateRect(hwparent , &rectImage, TRUE);
// add imageobj.renderImage(hBitmap); in wm_paint