anulax
/
stb
1
0
Fork 0
Code Issues Pull Requests Packages project_board Releases Wiki Activity

Fix the calculation of the input image shift when using subpixel regions

Browse Source
master
Jorge Rodriguez ago%!(EXTRA string=10 years)
parent a1ef3a1060 cf6f69cdc9
commit c81f0c62bc
1 changed files with 8 additions and 8 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 16
      stb_image_resize.h

16
stb_image_resize.h
Unescape View File

@ -1004,31 +1004,31 @@ stbir__inline static int stbir__edge_wrap(stbir_edge edge, int n, int max)
}
// What input pixels contribute to this output pixel?
static void stbir__calculate_sample_range_upsample(int n, float out_filter_radius, float scale_ratio, float out_shift, int* in_first_pixel, int* in_last_pixel, float* in_center_of_out)
static void stbir__calculate_sample_range_upsample(int n, float out_filter_radius, float scale_ratio, float in_shift, int* in_first_pixel, int* in_last_pixel, float* in_center_of_out)
{
float out_pixel_center = (float)n + 0.5f;
float out_pixel_influence_lowerbound = out_pixel_center - out_filter_radius;
float out_pixel_influence_upperbound = out_pixel_center + out_filter_radius;
float in_pixel_influence_lowerbound = (out_pixel_influence_lowerbound + out_shift) / scale_ratio;
float in_pixel_influence_upperbound = (out_pixel_influence_upperbound + out_shift) / scale_ratio;
float in_pixel_influence_lowerbound = out_pixel_influence_lowerbound / scale_ratio + in_shift;
float in_pixel_influence_upperbound = out_pixel_influence_upperbound / scale_ratio + in_shift;
*in_center_of_out = (out_pixel_center + out_shift) / scale_ratio;
*in_center_of_out = out_pixel_center / scale_ratio + in_shift;
*in_first_pixel = (int)(floor(in_pixel_influence_lowerbound + 0.5));
*in_last_pixel = (int)(floor(in_pixel_influence_upperbound - 0.5));
}
// What output pixels does this input pixel contribute to?
static void stbir__calculate_sample_range_downsample(int n, float in_pixels_radius, float scale_ratio, float out_shift, int* out_first_pixel, int* out_last_pixel, float* out_center_of_in)
static void stbir__calculate_sample_range_downsample(int n, float in_pixels_radius, float scale_ratio, float in_shift, int* out_first_pixel, int* out_last_pixel, float* out_center_of_in)
{
float in_pixel_center = (float)n + 0.5f;
float in_pixel_influence_lowerbound = in_pixel_center - in_pixels_radius;
float in_pixel_influence_upperbound = in_pixel_center + in_pixels_radius;
float out_pixel_influence_lowerbound = in_pixel_influence_lowerbound * scale_ratio - out_shift;
float out_pixel_influence_upperbound = in_pixel_influence_upperbound * scale_ratio - out_shift;
float out_pixel_influence_lowerbound = (in_pixel_influence_lowerbound - in_shift) * scale_ratio;
float out_pixel_influence_upperbound = (in_pixel_influence_upperbound - in_shift) * scale_ratio;
*out_center_of_in = in_pixel_center * scale_ratio - out_shift;
*out_center_of_in = (in_pixel_center - in_shift) * scale_ratio;
*out_first_pixel = (int)(floor(out_pixel_influence_lowerbound + 0.5));
*out_last_pixel = (int)(floor(out_pixel_influence_upperbound - 0.5));
}

Write Preview
Loading…
Cancel
Save