最近在看圖片相關的,就是圖片旋轉90度的算法,寫下來供記錄,旋轉90度分爲左旋轉和右旋轉。
左旋轉代碼如下:
//unsigned char *pImgData: 輸入圖像指針
//int WidthIn, int HeightIn:輸入圖像寬、高
//unsigned char *pImgOut: 旋轉後圖像指針
void RotateOfLeft(unsigned char *pImgData, int WidthIn, int HeightIn)
{
int i, j, tempSize;
int WidthOut = HeightIn;
int HeightOut = WidthIn;
unsigned char pImgtemp[148*36];
for (i = 0; i < HeightIn; i ++)
{
for (j = 0;j < WidthIn; j ++)
{
*(pImgtemp + i*WidthIn + j) = *(pImgData*WidthIn + j);
}
}
//memcpy(pImgtemp,pImgData,148*36);
for (i = 0; i < HeightOut; i ++)
{
for (j = 0;j < WidthOut; j ++)
{
*(pImgData + i*WidthOut + j) = *(pImgtemp + (j+1)*WidthIn - 1 - i);
}
}
}
右旋轉代碼如下:
//unsigned char *pImgData: 輸入圖像指針
//int WidthIn, int HeightIn:輸入圖像寬、高
//unsigned char *pImgOut: 旋轉後圖像指針
void RotateOfRight(unsigned char *pImgData, int WidthIn, int HeightIn, unsigned char *pImgOut)
{
int i, j;
int WidthOut = HeightIn;
int HeightOut = WidthIn;
for (i = 0; i < HeightOut; i ++)
{
for (j = 0;j < WidthOut; j ++)
{
*(pImgOut + i*WidthOut + j) = *(pImgData + (HeightIn - j - 1)*WidthIn + i);
}
}
}