图片比较 C

bool Compare(const char* aFile1,const char* aFile2,int x ,int y,int aWidth,int aHeight){CxImage* aDecoder1 = new CxImage();CxImage* aDecoder2 = new CxImage();/**1.Open file*/FILE* fp1 = fopen(aFile1,"rb");if(NULL == fp1){return OPEN_ERROR;}FILE* fp2 = fopen(aFile2,"rb");if(NULL == fp1){return OPEN_ERROR;}/**2.Decorder file */if(!aDecoder1->Decode(fp1,CXIMAGE_SUPPORT_PNG)){return DECODER_ERROR;}if(!aDecoder2->Decode(fp2,CXIMAGE_SUPPORT_PNG)){return DECODER_ERROR;}/**3.Get buffer*/BYTE *buf1= NULL;BYTE *buf2= NULL;int xCount = 0;int yCount = 0;int position = 0;int yChg = 0;buf1 = aDecoder1->GetBits();buf2 = aDecoder2->GetBits();int aPictureWidth = aDecoder1->GetWidth();int aPictureHeight = aDecoder1->GetHeight();if(aWidth !=0 && aPictureWidth != aWidth){aPictureWidth = aWidth;}if(aHeight !=0 && aPictureHeight != aHeight){aPictureHeight = aHeight;}if( x ){xCount = x;}if(y){yCount = aDecoder1->GetHeight() - (y + aHeight);}/**5.compare buffer*/for(int tempy = yCount ; yCount < tempy + aHeight ; yCount++){for(int tempx = xCount; xCount < tempx + aWidth ; xCount++){position = xCount + yCount*aDecoder1->GetWidth();int a = buf1[position];int b = buf2[position];if(buf1[position] != buf2[position]){return IMAGE_DIFF;}}}return IMAGE_SAME;}