标签:lan 意思 i++ 原因 了解 term blog 执行 new
水彩画还是挺不好模拟的,里面涉及的算法比較多,本文实现的水彩画算法主要參考以下两篇文章,《Interactive watercolor rendering with temporal coherence and abstraction》 、《Towards Photo Watercolorization with Artistic Verisimilitude》 。第一篇文章比較早。第二篇文章比較新。通过这两篇文章。能够对水彩画的模拟过程有一个大概了解。只是因为涉及的环节比較多。在实现过程中,有些地方做了简化,又新增了一些计算环节。整体上得到效果和文章比,并非严格一致。只是本文实现的水彩画算法执行较慢。还是比較耗时的。
边缘加深主要模拟颜料停止流动后。在边缘处的沉淀痕迹。颜料分散及紊流效果,主要是模拟水彩颜料渗透效果。只是本文实现的算法,颜料分散做的不是非常惬意。离真实水彩画那种颜料扩散及渗透效果还有非常大差距。
void* WaterColorThread(void *arg) { WaterColorInfo *watercolor_info = (WaterColorInfo *)arg; BMPINFO *pSrcBitmap = watercolor_info->pSrcBitmap; BMPINFO *pPaperBitmap = watercolor_info->pPaperBitmap; float *noise_perlin = watercolor_info->noise_perlin; float *mean = watercolor_info->mean; float *stdev = watercolor_info->stdev; int color_index = watercolor_info->color_index; int thread_id = watercolor_info->thread_id; int block_count = watercolor_info->block_count; // 数据转换 int width = pSrcBitmap->lWidth; int height= pSrcBitmap->lHeight; int size = width*height; float *rdata = (float *)malloc(size * sizeof(float)); float *gdata = (float *)malloc(size * sizeof(float)); float *bdata = (float *)malloc(size * sizeof(float)); ConvertToFloat(pSrcBitmap, rdata, gdata, bdata); // 简化细节 Abstraction(rdata, gdata, bdata, mean, stdev, width, height, color_index, thread_id); // 边缘抖动 EdgeWobbling(rdata, gdata, bdata, noise_perlin, width, height, block_count); // 边缘加深 EdgeDarkening(rdata, gdata, bdata, 1.5f, width, height); // 颜料分散 PigmentDispersion(rdata, gdata, bdata, 0.5f, width, height); // 紊流效果 TurbulenceFlow(rdata, gdata, bdata, noise_perlin, 2.0f, width, height); // 纸张纹理 PaperTexture(rdata, gdata, bdata, pPaperBitmap, 0.225f, width, height); // 数据转换 ConvertToUchar(rdata, gdata, bdata, pSrcBitmap); // 效果微调 ImageAdjust(pSrcBitmap); free(rdata); free(gdata); free(bdata); rdata = NULL; gdata = NULL; bdata = NULL; return NULL; }边缘抖动演示样例代码:
void EdgeWobbling(float *rdata, float *gdata, float *bdata, float *noise_perlin, int width, int height, int block_count) { int size = width*height; float strengthx = width / 3.5f; float strengthy = height*block_count / 3.5f; float strength = MAX(strengthx, strengthy); float *rcopy = (float *)malloc(size * sizeof(float)); float *gcopy = (float *)malloc(size * sizeof(float)); float *bcopy = (float *)malloc(size * sizeof(float)); memcpy(rcopy, rdata, size * sizeof(float)); memcpy(gcopy, gdata, size * sizeof(float)); memcpy(bcopy, bdata, size * sizeof(float)); int index = 0, new_index = 0; int p_offsetx = 0, p_offsety = 0, border_w = width - 1, border_h = height - 1; float *pNoiseData = noise_perlin; for (int i = 0; i < height - 1; i++) { for (int j = 0; j < width - 1; j++) { index = i*width + j; pNoiseData = noise_perlin + index; float new_posx = CLAMP0255_XY(j + (*(pNoiseData + 1) - *pNoiseData) * strength, border_w); float new_posy = CLAMP0255_XY(i + (*(pNoiseData + width) - *pNoiseData) * strength, border_h); int n_posx = (int)new_posx; int n_posy = (int)new_posy; float dx = new_posx - n_posx; float dy = new_posy - n_posy; p_offsetx = (n_posx != border_w); p_offsety = (n_posy != border_h); float r0 = 0.0f, g0 = 0.0f, b0 = 0.0f, r1 = 0.0f, g1 = 0.0f, b1 = 0.0f; new_index = n_posy*width + n_posx; r0 = *(rcopy + new_index); g0 = *(gcopy + new_index); b0 = *(bcopy + new_index); r1 = *(rcopy + new_index + p_offsetx); g1 = *(gcopy + new_index + p_offsetx); b1 = *(bcopy + new_index + p_offsetx); float r2 = 0.0f, g2 = 0.0f, b2 = 0.0f, r3 = 0.0f, g3 = 0.0f, b3 = 0.0f; new_index = (n_posy + p_offsety)*width + n_posx; r2 = *(rcopy + new_index); g2 = *(gcopy + new_index); b2 = *(bcopy + new_index); r3 = *(rcopy + new_index + p_offsetx); g3 = *(gcopy + new_index + p_offsetx); b3 = *(bcopy + new_index + p_offsetx); float r_val = 0.0f, g_val = 0.0f, b_val = 0.0f, fx1 = 0.0f, fx2 = 0.0f; fx1 = r0 + (r1 - r0) * dx; fx2 = r2 + (r3 - r2) * dx; r_val = fx1 + (fx2 - fx1) * dy; fx1 = g0 + (g1 - g0) * dx; fx2 = g2 + (g3 - g2) * dx; g_val = fx1 + (fx2 - fx1) * dy; fx1 = b0 + (b1 - b0) * dx; fx2 = b2 + (b3 - b2) * dx; b_val = fx1 + (fx2 - fx1) * dy; *(rdata + index) = *(rcopy + index)*0.4f + r_val*0.6f; *(gdata + index) = *(gcopy + index)*0.4f + g_val*0.6f; *(bdata + index) = *(bcopy + index)*0.4f + b_val*0.6f; } } free(rcopy); rcopy = NULL; free(gcopy); gcopy = NULL; free(bcopy); bcopy = NULL; }边缘加深演示样例代码:
void EdgeDarkening(float *rdata, float *gdata, float *bdata, float strength, int width, int height) { int step = width; int size = width*height; float *rcopy = (float *)malloc(size * sizeof(float)); float *gcopy = (float *)malloc(size * sizeof(float)); float *bcopy = (float *)malloc(size * sizeof(float)); memcpy(rcopy, rdata, size * sizeof(float)); memcpy(gcopy, gdata, size * sizeof(float)); memcpy(bcopy, bdata, size * sizeof(float)); int index = 0; float *pSrcRData = NULL, *pSrcGData = NULL, *pSrcBData = NULL; float *pNewRData = NULL, *pNewGData = NULL, *pNewBData = NULL; float *pLeftData = NULL, *pRightData = NULL, *pUpData = NULL, *pDownData = NULL; for (int i = 1; i < height - 1; i++) { for (int j = 1; j < width - 1; j++) { index = i*width + j; // red pNewRData = rcopy + index; pLeftData = pNewRData - 1; pRightData = pNewRData + 1; pUpData = pNewRData - step; pDownData = pNewRData + step; float gradient_r = fabs(*pRightData - *pLeftData) + fabs(*pDownData - *pUpData); // green pNewGData = gcopy + index; pLeftData = pNewGData - 1; pRightData = pNewGData + 1; pUpData = pNewGData - step; pDownData = pNewGData + step; float gradient_g = fabs(*pRightData - *pLeftData) + fabs(*pDownData - *pUpData); // blue pNewBData = bcopy + index; pLeftData = pNewBData - 1; pRightData = pNewBData + 1; pUpData = pNewBData - step; pDownData = pNewBData + step; float gradient_b = fabs(*pRightData - *pLeftData) + fabs(*pDownData - *pUpData); // result float gradient = (gradient_r + gradient_g + gradient_b)/* / 1.0f*/; pSrcRData = rdata + index; pSrcGData = gdata + index; pSrcBData = bdata + index; *pSrcRData = (float)CLAMP0255_XY(BousseauColorModel(*pSrcRData, gradient, strength), 1.0f); *pSrcGData = (float)CLAMP0255_XY(BousseauColorModel(*pSrcGData, gradient, strength), 1.0f); *pSrcBData = (float)CLAMP0255_XY(BousseauColorModel(*pSrcBData, gradient, strength), 1.0f); } } free(rcopy); rcopy = NULL; free(gcopy); gcopy = NULL; free(bcopy); bcopy = NULL; }颜料分散演示样例代码:
void PigmentDispersion(float *rdata, float *gdata, float *bdata, float strength, int width, int height) { int size = width*height; float *noise_gaussian = (float *)malloc(size * sizeof(float)); GaussianNoise(noise_gaussian, width, height); float *pSrcRData = rdata, *pSrcGData = gdata, *pSrcBData = bdata; for (int i = 0; i < size; i++, pSrcRData++, pSrcGData++, pSrcBData++) { *pSrcRData = (float)CLAMP0255_XY(BousseauColorModel(*pSrcRData, noise_gaussian[i], strength), 1.0f); *pSrcGData = (float)CLAMP0255_XY(BousseauColorModel(*pSrcGData, noise_gaussian[i], strength), 1.0f); *pSrcBData = (float)CLAMP0255_XY(BousseauColorModel(*pSrcBData, noise_gaussian[i], strength), 1.0f); } free(noise_gaussian); noise_gaussian = NULL; }假设颜料分散模拟的好,感觉还是有水彩画那么点意思的。只是如今也懒得优化了。以下是一些效果图:
标签:lan 意思 i++ 原因 了解 term blog 执行 new
原文地址:http://www.cnblogs.com/gccbuaa/p/7401038.html