基于C语言的最大值滤波

太过爱你忘了你带给我的痛 2022-02-21 08:44 353阅读 0赞

void MaxFilter(unsigned int *src, unsigned int *dst, int width, int height)
    {
    	assert(src != NULL);
    	assert(dst != NULL);
    	assert(width >= 0);
    	assert(height >= 0);
    
    	memset(expandDwtImageBuff, 0, EXPAND_IMAGE_SIZE * sizeof(unsigned int));
    	memset(maxCols, 0, EXPAND_IMAGE_SIZE * sizeof(unsigned int));
    	memset(maxRows, 0, EXPAND_IMAGE_SIZE * sizeof(unsigned int));
    	int expWidth = width + 2 * EXPAND_SIZE;
    	int expHeight = height + 2 * EXPAND_SIZE;
    
    	// 对输入图像进行扩展
    	for (int y = 0; y < height; y++)
    	{
    		for (int x = 0; x < width; x++)
    			expandDwtImageBuff[(y + EXPAND_SIZE) * expWidth + x + EXPAND_SIZE] = src[y * width + x];
    	}
    
    	// 找行方向的最大值（每一行41*1邻域的最大值）
    	unsigned int maxColValue = 0;	// 最大值
    	Point maxColPos = { 0, 0 };		// 最大值坐标
    	const int localDwtLen = 2 * EXPAND_SIZE + 1;
    
    	for (int y = EXPAND_SIZE; y < height + EXPAND_SIZE; y++)
    	{
    		int starty = y;
    		int endy = starty;
    		for (int x = EXPAND_SIZE; x < width + EXPAND_SIZE; x++)
    		{
    			if (expandDwtImageBuff[y * expWidth + x] > 0)
    			{
    				int startx = x - EXPAND_SIZE;
    				int endx = x + EXPAND_SIZE;
    
    				// 最大值求解
    				if (x == EXPAND_SIZE || maxColPos.x < startx)
    				{
    					GetMaxLocation(expandDwtImageBuff + starty * expWidth + startx, localDwtLen, &maxColValue, &maxColPos.x);
    					maxColPos.x += startx;
    					maxColPos.y += starty;
    					maxCols[y * expWidth + x] = maxColValue;
    				}
    				else
    				{
    
    					// 在移入的范围内，比较最大值和移入值
    					int newValue = expandDwtImageBuff[y * expWidth + endx];
    					if (newValue >= maxColValue)
    					{
    						maxColValue = newValue;
    						maxColPos.x = endx;
    						maxColPos.y = y;
    					}
    					maxCols[y * expWidth + x] = maxColValue;
    				}
    			}
    		}
    		maxColPos.x = 0;
    		maxColPos.y = 0;
    	}
    
    	// 找列方向的最大值（maxCols中每一列1*41邻域的最大值）
    	unsigned int maxRowValue = 0;
    	Point maxRowPos = { 0, 0 };
    	unsigned int localDwtBuff[2 * EXPAND_SIZE + 1] = { 0 };
    
    	for (int x = EXPAND_SIZE; x < width + EXPAND_SIZE; x++)
    	{
    		int startx = x;
    		int endx = startx;
    		for (int y = EXPAND_SIZE; y < height + EXPAND_SIZE; y++)
    		{
    			int starty = y - EXPAND_SIZE;
    			int endy = y + EXPAND_SIZE;
    
    			// 最大值求解
    			if (y == EXPAND_SIZE || maxRowPos.y < starty)
    			{
    				for (int i = 0; i < localDwtLen; i++)
    					localDwtBuff[i] = maxCols[(starty + i) * expWidth + startx];
    				GetMaxLocation(localDwtBuff, localDwtLen, &maxRowValue, &maxRowPos.y);
    				maxRowPos.y += starty;
    				maxRows[y * expWidth + x] = maxRowValue;
    			}
    			else
    			{
    				// 在移入的范围内，比较最大值和移入值
    				// 移入值为1*41矩形区域中最后一个值
    				int newValue = maxCols[endy * expWidth + x];
    				if (newValue >= maxRowValue)
    				{
    					maxRowValue = newValue;
    					maxRowPos.y = endy;
    				}
    				maxRows[y * expWidth + x] = maxRowValue;
    			}
    
    			if (expandDwtImageBuff[y * expWidth + x] == 0)
    				maxRows[y * expWidth + x] = 0;
    		}
    	}
    
    	// 切掉扩展出来的边缘
    	for (int y = 0; y < height; y++)
    	{
    		for (int x = 0; x < width; x++)
    			dst[y * width + x] = maxRows[(y + EXPAND_SIZE) * expWidth + x + EXPAND_SIZE];
    	}
    }