text: #include "image.h"
  #include "utils.h"
  #include "blas.h"
  #include "cuda.h"
  #include <stdio.h>
  #include <math.h>
  
  #define STB_IMAGE_IMPLEMENTATION
  #include "stb_image.h"
  #define STB_IMAGE_WRITE_IMPLEMENTATION
  #include "stb_image_write.h"
  
  int windows = 0;
  
  float colors[6][3] = { {1,0,1}, {0,0,1},{0,1,1},{0,1,0},{1,1,0},{1,0,0} };
  
  float get_color(int c, int x, int max)
  {
      float ratio = ((float)x/max)*5;
      int i = floor(ratio);
      int j = ceil(ratio);
      ratio -= i;
      float r = (1-ratio) * colors[i][c] + ratio*colors[j][c];
      //printf("%f\n", r);
      return r;
  }
  
  image mask_to_rgb(image mask)
  {
      int n = mask.c;
      image im = make_image(mask.w, mask.h, 3);
      int i, j;
      for(j = 0; j < n; ++j){
          int offset = j*123457 % n;
          float red = get_color(2,offset,n);
          float green = get_color(1,offset,n);
          float blue = get_color(0,offset,n);
          for(i = 0; i < im.w*im.h; ++i){
              im.data[i + 0*im.w*im.h] += mask.data[j*im.h*im.w + i]*red;
              im.data[i + 1*im.w*im.h] += mask.data[j*im.h*im.w + i]*green;
              im.data[i + 2*im.w*im.h] += mask.data[j*im.h*im.w + i]*blue;
          }
      }
      return im;
  }
  
  static float get_pixel(image m, int x, int y, int c)
  {
      assert(x < m.w && y < m.h && c < m.c);
      return m.data[c*m.h*m.w + y*m.w + x];
  }
  static float get_pixel_extend(image m, int x, int y, int c)
  {
      if(x < 0 || x >= m.w || y < 0 || y >= m.h) return 0;
      /*
      if(x < 0) x = 0;
      if(x >= m.w) x = m.w-1;
      if(y < 0) y = 0;
      if(y >= m.h) y = m.h-1;
      */
      if(c < 0 || c >= m.c) return 0;
      return get_pixel(m, x, y, c);
  }
  static void set_pixel(image m, int x, int y, int c, float val)
  {
      if (x < 0 || y < 0 || c < 0 || x >= m.w || y >= m.h || c >= m.c) return;
      assert(x < m.w && y < m.h && c < m.c);
      m.data[c*m.h*m.w + y*m.w + x] = val;
  }
  static void add_pixel(image m, int x, int y, int c, float val)
  {
      assert(x < m.w && y < m.h && c < m.c);
      m.data[c*m.h*m.w + y*m.w + x] += val;
  }
  
  static float bilinear_interpolate(image im, float x, float y, int c)
  {
      int ix = (int) floorf(x);
      int iy = (int) floorf(y);
  
      float dx = x - ix;
      float dy = y - iy;
  
      float val = (1-dy) * (1-dx) * get_pixel_extend(im, ix, iy, c) + 
          dy     * (1-dx) * get_pixel_extend(im, ix, iy+1, c) + 
          (1-dy) *   dx   * get_pixel_extend(im, ix+1, iy, c) +
          dy     *   dx   * get_pixel_extend(im, ix+1, iy+1, c);
      return val;
  }
  
  
  void composite_image(image source, image dest, int dx, int dy)
  {
      int x,y,k;
      for(k = 0; k < source.c; ++k){
          for(y = 0; y < source.h; ++y){
              for(x = 0; x < source.w; ++x){
                  float val = get_pixel(source, x, y, k);
                  float val2 = get_pixel_extend(dest, dx+x, dy+y, k);
                  set_pixel(dest, dx+x, dy+y, k, val * val2);
              }
          }
      }
  }
  
  image border_image(image a, int border)
  {
      image b = make_image(a.w + 2*border, a.h + 2*border, a.c);
      int x,y,k;
      for(k = 0; k < b.c; ++k){
          for(y = 0; y < b.h; ++y){
              for(x = 0; x < b.w; ++x){
                  float val = get_pixel_extend(a, x - border, y - border, k);
                  if(x - border < 0 || x - border >= a.w || y - border < 0 || y - border >= a.h) val = 1;
                  set_pixel(b, x, y, k, val);
              }
          }
      }
      return b;
  }
  
  image tile_images(image a, image b, int dx)
  {
      if(a.w == 0) return copy_image(b);
      image c = make_image(a.w + b.w + dx, (a.h > b.h) ? a.h : b.h, (a.c > b.c) ? a.c : b.c);
      fill_cpu(c.w*c.h*c.c, 1, c.data, 1);
      embed_image(a, c, 0, 0); 
      composite_image(b, c, a.w + dx, 0);
      return c;
  }
  
  image get_label(image **characters, char *string, int size)
  {
      size = size/10;
      if(size > 7) size = 7;
      image label = make_empty_image(0,0,0);
      while(*string){
          image l = characters[size][(int)*string];
          image n = tile_images(label, l, -size - 1 + (size+1)/2);
          free_image(label);
          label = n;
          ++string;
      }
      image b = border_image(label, label.h*.25);
      free_image(label);
      return b;
  }
  
  void draw_label(image a, int r, int c, image label, const float *rgb)
  {
      int w = label.w;
      int h = label.h;
      if (r - h >= 0) r = r - h;
  
      int i, j, k;
      for(j = 0; j < h && j + r < a.h; ++j){
          for(i = 0; i < w && i + c < a.w; ++i){
              for(k = 0; k < label.c; ++k){
                  float val = get_pixel(label, i, j, k);
                  set_pixel(a, i+c, j+r, k, rgb[k] * val);
              }
          }
      }
  }
  
  void draw_box(image a, int x1, int y1, int x2, int y2, float r, float g, float b)
  {
      //normalize_image(a);
      int i;
      if(x1 < 0) x1 = 0;
      if(x1 >= a.w) x1 = a.w-1;
      if(x2 < 0) x2 = 0;
      if(x2 >= a.w) x2 = a.w-1;
  
      if(y1 < 0) y1 = 0;
      if(y1 >= a.h) y1 = a.h-1;
      if(y2 < 0) y2 = 0;
      if(y2 >= a.h) y2 = a.h-1;
  
      for(i = x1; i <= x2; ++i){
          a.data[i + y1*a.w + 0*a.w*a.h] = r;
          a.data[i + y2*a.w + 0*a.w*a.h] = r;
  
          a.data[i + y1*a.w + 1*a.w*a.h] = g;
          a.data[i + y2*a.w + 1*a.w*a.h] = g;
  
          a.data[i + y1*a.w + 2*a.w*a.h] = b;
          a.data[i + y2*a.w + 2*a.w*a.h] = b;
      }
      for(i = y1; i <= y2; ++i){
          a.data[x1 + i*a.w + 0*a.w*a.h] = r;
          a.data[x2 + i*a.w + 0*a.w*a.h] = r;
  
          a.data[x1 + i*a.w + 1*a.w*a.h] = g;
          a.data[x2 + i*a.w + 1*a.w*a.h] = g;
  
          a.data[x1 + i*a.w + 2*a.w*a.h] = b;
          a.data[x2 + i*a.w + 2*a.w*a.h] = b;
      }
  }
  
  void draw_box_width(image a, int x1, int y1, int x2, int y2, int w, float r, float g, float b)
  {
      int i;
      for(i = 0; i < w; ++i){
          draw_box(a, x1+i, y1+i, x2-i, y2-i, r, g, b);
      }
  }
  
  void draw_bbox(image a, box bbox, int w, float r, float g, float b)
  {
      int left  = (bbox.x-bbox.w/2)*a.w;
      int right = (bbox.x+bbox.w/2)*a.w;
      int top   = (bbox.y-bbox.h/2)*a.h;
      int bot   = (bbox.y+bbox.h/2)*a.h;
  
      int i;
      for(i = 0; i < w; ++i){
          draw_box(a, left+i, top+i, right-i, bot-i, r, g, b);
      }
  }
  
  image **load_alphabet()
  {
      int i, j;
      const int nsize = 8;
      image **alphabets = calloc(nsize, sizeof(image));
      for(j = 0; j < nsize; ++j){
          alphabets[j] = calloc(128, sizeof(image));
          for(i = 32; i < 127; ++i){
              char buff[256];
              sprintf(buff, "data/labels/%d_%d.png", i, j);
              alphabets[j][i] = load_image_color(buff, 0, 0);
          }
      }
      return alphabets;
  }
  //image，概率，有几个，
  void draw_detections(image im, detection *dets, int num, float thresh, char **names, image **alphabet, int classes)
  {
      int i,j;
  
      for(i = 0; i < num; ++i){
          char labelstr[4096] = {0};
          int class = -1;
          for(j = 0; j < classes; ++j){
              if (dets[i].prob[j] > thresh){
                  if (class < 0) {
                      strcat(labelstr, names[j]);
                      class = j;
                  } else {
                      strcat(labelstr, ", ");
                      strcat(labelstr, names[j]);
                  }
                  printf("%s: %.0f%%\n", names[j], dets[i].prob[j]*100);
              }
          }
          if(class >= 0){
              int width = im.h * .006;
  
              /*
                 if(0){
                 width = pow(prob, 1./2.)*10+1;
                 alphabet = 0;
                 }
               */
  
              //printf("%d %s: %.0f%%\n", i, names[class], prob*100);
              int offset = class*123457 % classes;
              float red = get_color(2,offset,classes);
              float green = get_color(1,offset,classes);
              float blue = get_color(0,offset,classes);
              float rgb[3];
  
              //width = prob*20+2;
  
              rgb[0] = red;
              rgb[1] = green;
              rgb[2] = blue;
              box b = dets[i].bbox;
              //printf("%f %f %f %f\n", b.x, b.y, b.w, b.h);
  
              int left  = (b.x-b.w/2.)*im.w;
              int right = (b.x+b.w/2.)*im.w;
              int top   = (b.y-b.h/2.)*im.h;
              int bot   = (b.y+b.h/2.)*im.h;
  
              if(left < 0) left = 0;
              if(right > im.w-1) right = im.w-1;
              if(top < 0) top = 0;
              if(bot > im.h-1) bot = im.h-1;
  
              draw_box_width(im, left, top, right, bot, width, red, green, blue);
              if (alphabet) {
                  image label = get_label(alphabet, labelstr, (im.h*.03));
                  draw_label(im, top + width, left, label, rgb);
                  free_image(label);
              }
              if (dets[i].mask){
                  image mask = float_to_image(14, 14, 1, dets[i].mask);
                  image resized_mask = resize_image(mask, b.w*im.w, b.h*im.h);
                  image tmask = threshold_image(resized_mask, .5);
                  embed_image(tmask, im, left, top);
                  free_image(mask);
                  free_image(resized_mask);
                  free_image(tmask);
              }
          }
      }
  }
  
  void transpose_image(image im)
  {
      assert(im.w == im.h);
      int n, m;
      int c;
      for(c = 0; c < im.c; ++c){
          for(n = 0; n < im.w-1; ++n){
              for(m = n + 1; m < im.w; ++m){
                  float swap = im.data[m + im.w*(n + im.h*c)];
                  im.data[m + im.w*(n + im.h*c)] = im.data[n + im.w*(m + im.h*c)];
                  im.data[n + im.w*(m + im.h*c)] = swap;
              }
          }
      }
  }
  
  void rotate_image_cw(image im, int times)
  {
      assert(im.w == im.h);
      times = (times + 400) % 4;
      int i, x, y, c;
      int n = im.w;
      for(i = 0; i < times; ++i){
          for(c = 0; c < im.c; ++c){
              for(x = 0; x < n/2; ++x){
                  for(y = 0; y < (n-1)/2 + 1; ++y){
                      float temp = im.data[y + im.w*(x + im.h*c)];
                      im.data[y + im.w*(x + im.h*c)] = im.data[n-1-x + im.w*(y + im.h*c)];
                      im.data[n-1-x + im.w*(y + im.h*c)] = im.data[n-1-y + im.w*(n-1-x + im.h*c)];
                      im.data[n-1-y + im.w*(n-1-x + im.h*c)] = im.data[x + im.w*(n-1-y + im.h*c)];
                      im.data[x + im.w*(n-1-y + im.h*c)] = temp;
                  }
              }
          }
      }
  }
  
  void flip_image(image a)
  {
      int i,j,k;
      for(k = 0; k < a.c; ++k){
          for(i = 0; i < a.h; ++i){
              for(j = 0; j < a.w/2; ++j){
                  int index = j + a.w*(i + a.h*(k));
                  int flip = (a.w - j - 1) + a.w*(i + a.h*(k));
                  float swap = a.data[flip];
                  a.data[flip] = a.data[index];
                  a.data[index] = swap;
              }
          }
      }
  }
  
  image image_distance(image a, image b)
  {
      int i,j;
      image dist = make_image(a.w, a.h, 1);
      for(i = 0; i < a.c; ++i){
          for(j = 0; j < a.h*a.w; ++j){
              dist.data[j] += pow(a.data[i*a.h*a.w+j]-b.data[i*a.h*a.w+j],2);
          }
      }
      for(j = 0; j < a.h*a.w; ++j){
          dist.data[j] = sqrt(dist.data[j]);
      }
      return dist;
  }
  
  void ghost_image(image source, image dest, int dx, int dy)
  {
      int x,y,k;
      float max_dist = sqrt((-source.w/2. + .5)*(-source.w/2. + .5));
      for(k = 0; k < source.c; ++k){
          for(y = 0; y < source.h; ++y){
              for(x = 0; x < source.w; ++x){
                  float dist = sqrt((x - source.w/2. + .5)*(x - source.w/2. + .5) + (y - source.h/2. + .5)*(y - source.h/2. + .5));
                  float alpha = (1 - dist/max_dist);
                  if(alpha < 0) alpha = 0;
                  float v1 = get_pixel(source, x,y,k);
                  float v2 = get_pixel(dest, dx+x,dy+y,k);
                  float val = alpha*v1 + (1-alpha)*v2;
                  set_pixel(dest, dx+x, dy+y, k, val);
              }
          }
      }
  }
  
  void blocky_image(image im, int s)
  {
      int i,j,k;
      for(k = 0; k < im.c; ++k){
          for(j = 0; j < im.h; ++j){
              for(i = 0; i < im.w; ++i){
                  im.data[i + im.w*(j + im.h*k)] = im.data[i/s*s + im.w*(j/s*s + im.h*k)];
              }
          }
      }
  }
  
  void censor_image(image im, int dx, int dy, int w, int h)
  {
      int i,j,k;
      int s = 32;
      if(dx < 0) dx = 0;
      if(dy < 0) dy = 0;
  
      for(k = 0; k < im.c; ++k){
          for(j = dy; j < dy + h && j < im.h; ++j){
              for(i = dx; i < dx + w && i < im.w; ++i){
                  im.data[i + im.w*(j + im.h*k)] = im.data[i/s*s + im.w*(j/s*s + im.h*k)];
                  //im.data[i + j*im.w + k*im.w*im.h] = 0;
              }
          }
      }
  }
  
  void embed_image(image source, image dest, int dx, int dy)
  {
      int x,y,k;
      for(k = 0; k < source.c; ++k){
          for(y = 0; y < source.h; ++y){
              for(x = 0; x < source.w; ++x){
                  float val = get_pixel(source, x,y,k);
                  set_pixel(dest, dx+x, dy+y, k, val);
              }
          }
      }
  }
  
  image collapse_image_layers(image source, int border)
  {
      int h = source.h;
      h = (h+border)*source.c - border;
      image dest = make_image(source.w, h, 1);
      int i;
      for(i = 0; i < source.c; ++i){
          image layer = get_image_layer(source, i);
          int h_offset = i*(source.h+border);
          embed_image(layer, dest, 0, h_offset);
          free_image(layer);
      }
      return dest;
  }
  
  void constrain_image(image im)
  {
      int i;
      for(i = 0; i < im.w*im.h*im.c; ++i){
          if(im.data[i] < 0) im.data[i] = 0;
          if(im.data[i] > 1) im.data[i] = 1;
      }
  }
  
  void normalize_image(image p)
  {
      int i;
      float min = 9999999;
      float max = -999999;
  
      for(i = 0; i < p.h*p.w*p.c; ++i){
          float v = p.data[i];
          if(v < min) min = v;
          if(v > max) max = v;
      }
      if(max - min < .000000001){
          min = 0;
          max = 1;
      }
      for(i = 0; i < p.c*p.w*p.h; ++i){
          p.data[i] = (p.data[i] - min)/(max-min);
      }
  }
  
  void normalize_image2(image p)
  {
      float *min = calloc(p.c, sizeof(float));
      float *max = calloc(p.c, sizeof(float));
      int i,j;
      for(i = 0; i < p.c; ++i) min[i] = max[i] = p.data[i*p.h*p.w];
  
      for(j = 0; j < p.c; ++j){
          for(i = 0; i < p.h*p.w; ++i){
              float v = p.data[i+j*p.h*p.w];
              if(v < min[j]) min[j] = v;
              if(v > max[j]) max[j] = v;
          }
      }
      for(i = 0; i < p.c; ++i){
          if(max[i] - min[i] < .000000001){
              min[i] = 0;
              max[i] = 1;
          }
      }
      for(j = 0; j < p.c; ++j){
          for(i = 0; i < p.w*p.h; ++i){
              p.data[i+j*p.h*p.w] = (p.data[i+j*p.h*p.w] - min[j])/(max[j]-min[j]);
          }
      }
      free(min);
      free(max);
  }
  
  void copy_image_into(image src, image dest)
  {
      memcpy(dest.data, src.data, src.h*src.w*src.c*sizeof(float));
  }
  
  image copy_image(image p)
  {
      image copy = p;
      copy.data = calloc(p.h*p.w*p.c, sizeof(float));
      memcpy(copy.data, p.data, p.h*p.w*p.c*sizeof(float));
      return copy;
  }
  
  void rgbgr_image(image im)
  {
      int i;
      for(i = 0; i < im.w*im.h; ++i){
          float swap = im.data[i];
          im.data[i] = im.data[i+im.w*im.h*2];
          im.data[i+im.w*im.h*2] = swap;
      }
  }
  
  int show_image(image p, const char *name, int ms)
  {
  #ifdef OPENCV
      int c = show_image_cv(p, name, ms);
      return c;
  #else
      fprintf(stderr, "Not compiled with OpenCV, saving to %s.png instead\n", name);
      save_image(p, name);
      return -1;
  #endif
  }
  
  void save_image_options(image im, const char *name, IMTYPE f, int quality)
  {
      char buff[256];
      //sprintf(buff, "%s (%d)", name, windows);
      if(f == PNG)       sprintf(buff, "%s.png", name);
      else if (f == BMP) sprintf(buff, "%s.bmp", name);
      else if (f == TGA) sprintf(buff, "%s.tga", name);
      else if (f == JPG) sprintf(buff, "%s.jpg", name);
      else               sprintf(buff, "%s.png", name);
      unsigned char *data = calloc(im.w*im.h*im.c, sizeof(char));
      int i,k;
      for(k = 0; k < im.c; ++k){
          for(i = 0; i < im.w*im.h; ++i){
              data[i*im.c+k] = (unsigned char) (255*im.data[i + k*im.w*im.h]);
          }
      }
      int success = 0;
      if(f == PNG)       success = stbi_write_png(buff, im.w, im.h, im.c, data, im.w*im.c);
      else if (f == BMP) success = stbi_write_bmp(buff, im.w, im.h, im.c, data);
      else if (f == TGA) success = stbi_write_tga(buff, im.w, im.h, im.c, data);
      else if (f == JPG) success = stbi_write_jpg(buff, im.w, im.h, im.c, data, quality);
      free(data);
      if(!success) fprintf(stderr, "Failed to write image %s\n", buff);
  }
  
  void save_image(image im, const char *name)
  {
      save_image_options(im, name, JPG, 80);
  }
  
  void show_image_layers(image p, char *name)
  {
      int i;
      char buff[256];
      for(i = 0; i < p.c; ++i){
          sprintf(buff, "%s - Layer %d", name, i);
          image layer = get_image_layer(p, i);
          show_image(layer, buff, 1);
          free_image(layer);
      }
  }
  
  void show_image_collapsed(image p, char *name)
  {
      image c = collapse_image_layers(p, 1);
      show_image(c, name, 1);
      free_image(c);
  }
  
  image make_empty_image(int w, int h, int c)
  {
      image out;
      out.data = 0;
      out.h = h;
      out.w = w;
      out.c = c;
      return out;
  }
  
  image make_image(int w, int h, int c)
  {
      image out = make_empty_image(w,h,c);
      out.data = calloc(h*w*c, sizeof(float));
      return out;
  }
  
  image make_random_image(int w, int h, int c)
  {
      image out = make_empty_image(w,h,c);
      out.data = calloc(h*w*c, sizeof(float));
      int i;
      for(i = 0; i < w*h*c; ++i){
          out.data[i] = (rand_normal() * .25) + .5;
      }
      return out;
  }
  
  image float_to_image(int w, int h, int c, float *data)
  {
      image out = make_empty_image(w,h,c);
      out.data = data;
      return out;
  }
  
  void place_image(image im, int w, int h, int dx, int dy, image canvas)
  {
      int x, y, c;
      for(c = 0; c < im.c; ++c){
          for(y = 0; y < h; ++y){
              for(x = 0; x < w; ++x){
                  float rx = ((float)x / w) * im.w;
                  float ry = ((float)y / h) * im.h;
                  float val = bilinear_interpolate(im, rx, ry, c);
                  set_pixel(canvas, x + dx, y + dy, c, val);
              }
          }
      }
  }
  
  image center_crop_image(image im, int w, int h)
  {
      int m = (im.w < im.h) ? im.w : im.h;   
      image c = crop_image(im, (im.w - m) / 2, (im.h - m)/2, m, m);
      image r = resize_image(c, w, h);
      free_image(c);
      return r;
  }
  
  image rotate_crop_image(image im, float rad, float s, int w, int h, float dx, float dy, float aspect)
  {
      int x, y, c;
      float cx = im.w/2.;
      float cy = im.h/2.;
      image rot = make_image(w, h, im.c);
      for(c = 0; c < im.c; ++c){
          for(y = 0; y < h; ++y){
              for(x = 0; x < w; ++x){
                  float rx = cos(rad)*((x - w/2.)/s*aspect + dx/s*aspect) - sin(rad)*((y - h/2.)/s + dy/s) + cx;
                  float ry = sin(rad)*((x - w/2.)/s*aspect + dx/s*aspect) + cos(rad)*((y - h/2.)/s + dy/s) + cy;
                  float val = bilinear_interpolate(im, rx, ry, c);
                  set_pixel(rot, x, y, c, val);
              }
          }
      }
      return rot;
  }
  
  image rotate_image(image im, float rad)
  {
      int x, y, c;
      float cx = im.w/2.;
      float cy = im.h/2.;
      image rot = make_image(im.w, im.h, im.c);
      for(c = 0; c < im.c; ++c){
          for(y = 0; y < im.h; ++y){
              for(x = 0; x < im.w; ++x){
                  float rx = cos(rad)*(x-cx) - sin(rad)*(y-cy) + cx;
                  float ry = sin(rad)*(x-cx) + cos(rad)*(y-cy) + cy;
                  float val = bilinear_interpolate(im, rx, ry, c);
                  set_pixel(rot, x, y, c, val);
              }
          }
      }
      return rot;
  }
  
  void fill_image(image m, float s)
  {
      int i;
      for(i = 0; i < m.h*m.w*m.c; ++i) m.data[i] = s;
  }
  
  void translate_image(image m, float s)
  {
      int i;
      for(i = 0; i < m.h*m.w*m.c; ++i) m.data[i] += s;
  }
  
  void scale_image(image m, float s)
  {
      int i;
      for(i = 0; i < m.h*m.w*m.c; ++i) m.data[i] *= s;
  }
  
  image crop_image(image im, int dx, int dy, int w, int h)
  {
      image cropped = make_image(w, h, im.c);
      int i, j, k;
      for(k = 0; k < im.c; ++k){
          for(j = 0; j < h; ++j){
              for(i = 0; i < w; ++i){
                  int r = j + dy;
                  int c = i + dx;
                  float val = 0;
                  r = constrain_int(r, 0, im.h-1);
                  c = constrain_int(c, 0, im.w-1);
                  val = get_pixel(im, c, r, k);
                  set_pixel(cropped, i, j, k, val);
              }
          }
      }
      return cropped;
  }
  
  int best_3d_shift_r(image a, image b, int min, int max)
  {
      if(min == max) return min;
      int mid = floor((min + max) / 2.);
      image c1 = crop_image(b, 0, mid, b.w, b.h);
      image c2 = crop_image(b, 0, mid+1, b.w, b.h);
      float d1 = dist_array(c1.data, a.data, a.w*a.h*a.c, 10);
      float d2 = dist_array(c2.data, a.data, a.w*a.h*a.c, 10);
      free_image(c1);
      free_image(c2);
      if(d1 < d2) return best_3d_shift_r(a, b, min, mid);
      else return best_3d_shift_r(a, b, mid+1, max);
  }
  
  int best_3d_shift(image a, image b, int min, int max)
  {
      int i;
      int best = 0;
      float best_distance = FLT_MAX;
      for(i = min; i <= max; i += 2){
          image c = crop_image(b, 0, i, b.w, b.h);
          float d = dist_array(c.data, a.data, a.w*a.h*a.c, 100);
          if(d < best_distance){
              best_distance = d;
              best = i;
          }
          printf("%d %f\n", i, d);
          free_image(c);
      }
      return best;
  }
  
  void composite_3d(char *f1, char *f2, char *out, int delta)
  {
      if(!out) out = "out";
      image a = load_image(f1, 0,0,0);
      image b = load_image(f2, 0,0,0);
      int shift = best_3d_shift_r(a, b, -a.h/100, a.h/100);
  
      image c1 = crop_image(b, 10, shift, b.w, b.h);
      float d1 = dist_array(c1.data, a.data, a.w*a.h*a.c, 100);
      image c2 = crop_image(b, -10, shift, b.w, b.h);
      float d2 = dist_array(c2.data, a.data, a.w*a.h*a.c, 100);
  
      if(d2 < d1 && 0){
          image swap = a;
          a = b;
          b = swap;
          shift = -shift;
          printf("swapped, %d\n", shift);
      }
      else{
          printf("%d\n", shift);
      }
  
      image c = crop_image(b, delta, shift, a.w, a.h);
      int i;
      for(i = 0; i < c.w*c.h; ++i){
          c.data[i] = a.data[i];
      }
      save_image(c, out);
  }
  
  void letterbox_image_into(image im, int w, int h, image boxed)
  {
      int new_w = im.w;
      int new_h = im.h;
      if (((float)w/im.w) < ((float)h/im.h)) {
          new_w = w;
          new_h = (im.h * w)/im.w;
      } else {
          new_h = h;
          new_w = (im.w * h)/im.h;
      }
      image resized = resize_image(im, new_w, new_h);
      embed_image(resized, boxed, (w-new_w)/2, (h-new_h)/2); 
      free_image(resized);
  }
  
  image letterbox_image(image im, int w, int h)
  {
      int new_w = im.w;
      int new_h = im.h;
      if (((float)w/im.w) < ((float)h/im.h)) {
          new_w = w;
          new_h = (im.h * w)/im.w;
      } else {
          new_h = h;
          new_w = (im.w * h)/im.h;
      }
      image resized = resize_image(im, new_w, new_h);
      image boxed = make_image(w, h, im.c);
      fill_image(boxed, .5);
      //int i;
      //for(i = 0; i < boxed.w*boxed.h*boxed.c; ++i) boxed.data[i] = 0;
      embed_image(resized, boxed, (w-new_w)/2, (h-new_h)/2); 
      free_image(resized);
      return boxed;
  }
  
  image resize_max(image im, int max)
  {
      int w = im.w;
      int h = im.h;
      if(w > h){
          h = (h * max) / w;
          w = max;
      } else {
          w = (w * max) / h;
          h = max;
      }
      if(w == im.w && h == im.h) return im;
      image resized = resize_image(im, w, h);
      return resized;
  }
  
  image resize_min(image im, int min)
  {
      int w = im.w;
      int h = im.h;
      if(w < h){
          h = (h * min) / w;
          w = min;
      } else {
          w = (w * min) / h;
          h = min;
      }
      if(w == im.w && h == im.h) return im;
      image resized = resize_image(im, w, h);
      return resized;
  }
  
  image random_crop_image(image im, int w, int h)
  {
      int dx = rand_int(0, im.w - w);
      int dy = rand_int(0, im.h - h);
      image crop = crop_image(im, dx, dy, w, h);
      return crop;
  }
  
  augment_args random_augment_args(image im, float angle, float aspect, int low, int high, int w, int h)
  {
      augment_args a = {0};
      aspect = rand_scale(aspect);
      int r = rand_int(low, high);
      int min = (im.h < im.w*aspect) ? im.h : im.w*aspect;
      float scale = (float)r / min;
  
      float rad = rand_uniform(-angle, angle) * TWO_PI / 360.;
  
      float dx = (im.w*scale/aspect - w) / 2.;
      float dy = (im.h*scale - w) / 2.;
      //if(dx < 0) dx = 0;
      //if(dy < 0) dy = 0;
      dx = rand_uniform(-dx, dx);
      dy = rand_uniform(-dy, dy);
  
      a.rad = rad;
      a.scale = scale;
      a.w = w;
      a.h = h;
      a.dx = dx;
      a.dy = dy;
      a.aspect = aspect;
      return a;
  }
  
  image random_augment_image(image im, float angle, float aspect, int low, int high, int w, int h)
  {
      augment_args a = random_augment_args(im, angle, aspect, low, high, w, h);
      image crop = rotate_crop_image(im, a.rad, a.scale, a.w, a.h, a.dx, a.dy, a.aspect);
      return crop;
  }
  
  float three_way_max(float a, float b, float c)
  {
      return (a > b) ? ( (a > c) ? a : c) : ( (b > c) ? b : c) ;
  }
  
  float three_way_min(float a, float b, float c)
  {
      return (a < b) ? ( (a < c) ? a : c) : ( (b < c) ? b : c) ;
  }
  
  void yuv_to_rgb(image im)
  {
      assert(im.c == 3);
      int i, j;
      float r, g, b;
      float y, u, v;
      for(j = 0; j < im.h; ++j){
          for(i = 0; i < im.w; ++i){
              y = get_pixel(im, i , j, 0);
              u = get_pixel(im, i , j, 1);
              v = get_pixel(im, i , j, 2);
  
              r = y + 1.13983*v;
              g = y + -.39465*u + -.58060*v;
              b = y + 2.03211*u;
  
              set_pixel(im, i, j, 0, r);
              set_pixel(im, i, j, 1, g);
              set_pixel(im, i, j, 2, b);
          }
      }
  }
  
  void rgb_to_yuv(image im)
  {
      assert(im.c == 3);
      int i, j;
      float r, g, b;
      float y, u, v;
      for(j = 0; j < im.h; ++j){
          for(i = 0; i < im.w; ++i){
              r = get_pixel(im, i , j, 0);
              g = get_pixel(im, i , j, 1);
              b = get_pixel(im, i , j, 2);
  
              y = .299*r + .587*g + .114*b;
              u = -.14713*r + -.28886*g + .436*b;
              v = .615*r + -.51499*g + -.10001*b;
  
              set_pixel(im, i, j, 0, y);
              set_pixel(im, i, j, 1, u);
              set_pixel(im, i, j, 2, v);
          }
      }
  }
  
  // http://www.cs.rit.edu/~ncs/color/t_convert.html
  void rgb_to_hsv(image im)
  {
      assert(im.c == 3);
      int i, j;
      float r, g, b;
      float h, s, v;
      for(j = 0; j < im.h; ++j){
          for(i = 0; i < im.w; ++i){
              r = get_pixel(im, i , j, 0);
              g = get_pixel(im, i , j, 1);
              b = get_pixel(im, i , j, 2);
              float max = three_way_max(r,g,b);
              float min = three_way_min(r,g,b);
              float delta = max - min;
              v = max;
              if(max == 0){
                  s = 0;
                  h = 0;
              }else{
                  s = delta/max;
                  if(r == max){
                      h = (g - b) / delta;
                  } else if (g == max) {
                      h = 2 + (b - r) / delta;
                  } else {
                      h = 4 + (r - g) / delta;
                  }
                  if (h < 0) h += 6;
                  h = h/6.;
              }
              set_pixel(im, i, j, 0, h);
              set_pixel(im, i, j, 1, s);
              set_pixel(im, i, j, 2, v);
          }
      }
  }
  
  void hsv_to_rgb(image im)
  {
      assert(im.c == 3);
      int i, j;
      float r, g, b;
      float h, s, v;
      float f, p, q, t;
      for(j = 0; j < im.h; ++j){
          for(i = 0; i < im.w; ++i){
              h = 6 * get_pixel(im, i , j, 0);
              s = get_pixel(im, i , j, 1);
              v = get_pixel(im, i , j, 2);
              if (s == 0) {
                  r = g = b = v;
              } else {
                  int index = floor(h);
                  f = h - index;
                  p = v*(1-s);
                  q = v*(1-s*f);
                  t = v*(1-s*(1-f));
                  if(index == 0){
                      r = v; g = t; b = p;
                  } else if(index == 1){
                      r = q; g = v; b = p;
                  } else if(index == 2){
                      r = p; g = v; b = t;
                  } else if(index == 3){
                      r = p; g = q; b = v;
                  } else if(index == 4){
                      r = t; g = p; b = v;
                  } else {
                      r = v; g = p; b = q;
                  }
              }
              set_pixel(im, i, j, 0, r);
              set_pixel(im, i, j, 1, g);
              set_pixel(im, i, j, 2, b);
          }
      }
  }
  
  void grayscale_image_3c(image im)
  {
      assert(im.c == 3);
      int i, j, k;
      float scale[] = {0.299, 0.587, 0.114};
      for(j = 0; j < im.h; ++j){
          for(i = 0; i < im.w; ++i){
              float val = 0;
              for(k = 0; k < 3; ++k){
                  val += scale[k]*get_pixel(im, i, j, k);
              }
              im.data[0*im.h*im.w + im.w*j + i] = val;
              im.data[1*im.h*im.w + im.w*j + i] = val;
              im.data[2*im.h*im.w + im.w*j + i] = val;
          }
      }
  }
  
  image grayscale_image(image im)
  {
      assert(im.c == 3);
      int i, j, k;
      image gray = make_image(im.w, im.h, 1);
      float scale[] = {0.299, 0.587, 0.114};
      for(k = 0; k < im.c; ++k){
          for(j = 0; j < im.h; ++j){
              for(i = 0; i < im.w; ++i){
                  gray.data[i+im.w*j] += scale[k]*get_pixel(im, i, j, k);
              }
          }
      }
      return gray;
  }
  
  image threshold_image(image im, float thresh)
  {
      int i;
      image t = make_image(im.w, im.h, im.c);
      for(i = 0; i < im.w*im.h*im.c; ++i){
          t.data[i] = im.data[i]>thresh ? 1 : 0;
      }
      return t;
  }
  
  image blend_image(image fore, image back, float alpha)
  {
      assert(fore.w == back.w && fore.h == back.h && fore.c == back.c);
      image blend = make_image(fore.w, fore.h, fore.c);
      int i, j, k;
      for(k = 0; k < fore.c; ++k){
          for(j = 0; j < fore.h; ++j){
              for(i = 0; i < fore.w; ++i){
                  float val = alpha * get_pixel(fore, i, j, k) + 
                      (1 - alpha)* get_pixel(back, i, j, k);
                  set_pixel(blend, i, j, k, val);
              }
          }
      }
      return blend;
  }
  
  void scale_image_channel(image im, int c, float v)
  {
      int i, j;
      for(j = 0; j < im.h; ++j){
          for(i = 0; i < im.w; ++i){
              float pix = get_pixel(im, i, j, c);
              pix = pix*v;
              set_pixel(im, i, j, c, pix);
          }
      }
  }
  
  void translate_image_channel(image im, int c, float v)
  {
      int i, j;
      for(j = 0; j < im.h; ++j){
          for(i = 0; i < im.w; ++i){
              float pix = get_pixel(im, i, j, c);
              pix = pix+v;
              set_pixel(im, i, j, c, pix);
          }
      }
  }
  
  image binarize_image(image im)
  {
      image c = copy_image(im);
      int i;
      for(i = 0; i < im.w * im.h * im.c; ++i){
          if(c.data[i] > .5) c.data[i] = 1;
          else c.data[i] = 0;
      }
      return c;
  }
  
  void saturate_image(image im, float sat)
  {
      rgb_to_hsv(im);
      scale_image_channel(im, 1, sat);
      hsv_to_rgb(im);
      constrain_image(im);
  }
  
  void hue_image(image im, float hue)
  {
      rgb_to_hsv(im);
      int i;
      for(i = 0; i < im.w*im.h; ++i){
          im.data[i] = im.data[i] + hue;
          if (im.data[i] > 1) im.data[i] -= 1;
          if (im.data[i] < 0) im.data[i] += 1;
      }
      hsv_to_rgb(im);
      constrain_image(im);
  }
  
  void exposure_image(image im, float sat)
  {
      rgb_to_hsv(im);
      scale_image_channel(im, 2, sat);
      hsv_to_rgb(im);
      constrain_image(im);
  }
  
  void distort_image(image im, float hue, float sat, float val)
  {
      rgb_to_hsv(im);
      scale_image_channel(im, 1, sat);
      scale_image_channel(im, 2, val);
      int i;
      for(i = 0; i < im.w*im.h; ++i){
          im.data[i] = im.data[i] + hue;
          if (im.data[i] > 1) im.data[i] -= 1;
          if (im.data[i] < 0) im.data[i] += 1;
      }
      hsv_to_rgb(im);
      constrain_image(im);
  }
  
  void random_distort_image(image im, float hue, float saturation, float exposure)
  {
      float dhue = rand_uniform(-hue, hue);
      float dsat = rand_scale(saturation);
      float dexp = rand_scale(exposure);
      distort_image(im, dhue, dsat, dexp);
  }
  
  void saturate_exposure_image(image im, float sat, float exposure)
  {
      rgb_to_hsv(im);
      scale_image_channel(im, 1, sat);
      scale_image_channel(im, 2, exposure);
      hsv_to_rgb(im);
      constrain_image(im);
  }
  
  image resize_image(image im, int w, int h)
  {
      image resized = make_image(w, h, im.c);   
      image part = make_image(w, im.h, im.c);
      int r, c, k;
      float w_scale = (float)(im.w - 1) / (w - 1);
      float h_scale = (float)(im.h - 1) / (h - 1);
      for(k = 0; k < im.c; ++k){
          for(r = 0; r < im.h; ++r){
              for(c = 0; c < w; ++c){
                  float val = 0;
                  if(c == w-1 || im.w == 1){
                      val = get_pixel(im, im.w-1, r, k);
                  } else {
                      float sx = c*w_scale;
                      int ix = (int) sx;
                      float dx = sx - ix;
                      val = (1 - dx) * get_pixel(im, ix, r, k) + dx * get_pixel(im, ix+1, r, k);
                  }
                  set_pixel(part, c, r, k, val);
              }
          }
      }
      for(k = 0; k < im.c; ++k){
          for(r = 0; r < h; ++r){
              float sy = r*h_scale;
              int iy = (int) sy;
              float dy = sy - iy;
              for(c = 0; c < w; ++c){
                  float val = (1-dy) * get_pixel(part, c, iy, k);
                  set_pixel(resized, c, r, k, val);
              }
              if(r == h-1 || im.h == 1) continue;
              for(c = 0; c < w; ++c){
                  float val = dy * get_pixel(part, c, iy+1, k);
                  add_pixel(resized, c, r, k, val);
              }
          }
      }
  
      free_image(part);
      return resized;
  }
  
  
  void test_resize(char *filename)
  {
      image im = load_image(filename, 0,0, 3);
      float mag = mag_array(im.data, im.w*im.h*im.c);
      printf("L2 Norm: %f\n", mag);
      image gray = grayscale_image(im);
  
      image c1 = copy_image(im);
      image c2 = copy_image(im);
      image c3 = copy_image(im);
      image c4 = copy_image(im);
      distort_image(c1, .1, 1.5, 1.5);
      distort_image(c2, -.1, .66666, .66666);
      distort_image(c3, .1, 1.5, .66666);
      distort_image(c4, .1, .66666, 1.5);
  
  
      show_image(im,   "Original", 1);
      show_image(gray, "Gray", 1);
      show_image(c1, "C1", 1);
      show_image(c2, "C2", 1);
      show_image(c3, "C3", 1);
      show_image(c4, "C4", 1);
  #ifdef OPENCV
      while(1){
          image aug = random_augment_image(im, 0, .75, 320, 448, 320, 320);
          show_image(aug, "aug", 1);
          free_image(aug);
  
  
          float exposure = 1.15;
          float saturation = 1.15;
          float hue = .05;
  
          image c = copy_image(im);
  
          float dexp = rand_scale(exposure);
          float dsat = rand_scale(saturation);
          float dhue = rand_uniform(-hue, hue);
  
          distort_image(c, dhue, dsat, dexp);
          show_image(c, "rand", 1);
          printf("%f %f %f\n", dhue, dsat, dexp);
          free_image(c);
      }
  #endif
  }
  
  
  image load_image_stb(char *filename, int channels)
  {
      int w, h, c;
      unsigned char *data = stbi_load(filename, &w, &h, &c, channels);
      if (!data) {
          fprintf(stderr, "Cannot load image \"%s\"\nSTB Reason: %s\n", filename, stbi_failure_reason());
          exit(0);
      }
      if(channels) c = channels;
      int i,j,k;
      image im = make_image(w, h, c);
      for(k = 0; k < c; ++k){
          for(j = 0; j < h; ++j){
              for(i = 0; i < w; ++i){
                  int dst_index = i + w*j + w*h*k;
                  int src_index = k + c*i + c*w*j;
                  im.data[dst_index] = (float)data[src_index]/255.;
              }
          }
      }
      free(data);
      return im;
  }
  
  image load_image(char *filename, int w, int h, int c)
  {
  #ifdef OPENCV
      image out = load_image_cv(filename, c);
  #else
      image out = load_image_stb(filename, c);
  #endif
  
      if((h && w) && (h != out.h || w != out.w)){
          image resized = resize_image(out, w, h);
          free_image(out);
          out = resized;
      }
      return out;
  }
  
  image load_image_color(char *filename, int w, int h)
  {
      return load_image(filename, w, h, 3);
  }
  
  image get_image_layer(image m, int l)
  {
      image out = make_image(m.w, m.h, 1);
      int i;
      for(i = 0; i < m.h*m.w; ++i){
          out.data[i] = m.data[i+l*m.h*m.w];
      }
      return out;
  }
  void print_image(image m)
  {
      int i, j, k;
      for(i =0 ; i < m.c; ++i){
          for(j =0 ; j < m.h; ++j){
              for(k = 0; k < m.w; ++k){
                  printf("%.2lf, ", m.data[i*m.h*m.w + j*m.w + k]);
                  if(k > 30) break;
              }
              printf("\n");
              if(j > 30) break;
          }
          printf("\n");
      }
      printf("\n");
  }
  
  image collapse_images_vert(image *ims, int n)
  {
      int color = 1;
      int border = 1;
      int h,w,c;
      w = ims[0].w;
      h = (ims[0].h + border) * n - border;
      c = ims[0].c;
      if(c != 3 || !color){
          w = (w+border)*c - border;
          c = 1;
      }
  
      image filters = make_image(w, h, c);
      int i,j;
      for(i = 0; i < n; ++i){
          int h_offset = i*(ims[0].h+border);
          image copy = copy_image(ims[i]);
          //normalize_image(copy);
          if(c == 3 && color){
              embed_image(copy, filters, 0, h_offset);
          }
          else{
              for(j = 0; j < copy.c; ++j){
                  int w_offset = j*(ims[0].w+border);
                  image layer = get_image_layer(copy, j);
                  embed_image(layer, filters, w_offset, h_offset);
                  free_image(layer);
              }
          }
          free_image(copy);
      }
      return filters;
  } 
  
  image collapse_images_horz(image *ims, int n)
  {
      int color = 1;
      int border = 1;
      int h,w,c;
      int size = ims[0].h;
      h = size;
      w = (ims[0].w + border) * n - border;
      c = ims[0].c;
      if(c != 3 || !color){
          h = (h+border)*c - border;
          c = 1;
      }
  
      image filters = make_image(w, h, c);
      int i,j;
      for(i = 0; i < n; ++i){
          int w_offset = i*(size+border);
          image copy = copy_image(ims[i]);
          //normalize_image(copy);
          if(c == 3 && color){
              embed_image(copy, filters, w_offset, 0);
          }
          else{
              for(j = 0; j < copy.c; ++j){
                  int h_offset = j*(size+border);
                  image layer = get_image_layer(copy, j);
                  embed_image(layer, filters, w_offset, h_offset);
                  free_image(layer);
              }
          }
          free_image(copy);
      }
      return filters;
  } 
  
  void show_image_normalized(image im, const char *name)
  {
      image c = copy_image(im);
      normalize_image(c);
      show_image(c, name, 1);
      free_image(c);
  }
  
  void show_images(image *ims, int n, char *window)
  {
      image m = collapse_images_vert(ims, n);
      /*
         int w = 448;
         int h = ((float)m.h/m.w) * 448;
         if(h > 896){
         h = 896;
         w = ((float)m.w/m.h) * 896;
         }
         image sized = resize_image(m, w, h);
       */
      normalize_image(m);
      save_image(m, window);
      show_image(m, window, 1);
      free_image(m);
  }
  
  void free_image(image m)
  {
      if(m.data){
          free(m.data);
      }
  }
  