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

Do the multiply inline, it should be a tad faster and not corrupt our data.

Browse Source
master
Jorge Rodriguez ago%!(EXTRA string=11 years)
parent 13acfca829
commit d75488b0e8
2 changed files with 36 additions and 31 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. 63
      stb_resample.h
  2. 4
      tests/resample_test.cpp

63
stb_resample.h
Unescape View File

@ -1003,76 +1003,81 @@ static float* stbr__get_ring_buffer_scanline(int get_scanline, float* ring_buffe
static stbr_inline void stbr__encode_scanline(void* output_buffer, int output_texel_index, float* encode_buffer, int encode_texel_index, int channels, int premul_alpha_channel, int decode)
{
int n;
float divide_alpha = 1;
if (premul_alpha_channel)
{
for (n = 0; n < channels; n++)
{
if (n == premul_alpha_channel)
continue;
encode_buffer[encode_texel_index + n] /= encode_buffer[encode_texel_index + premul_alpha_channel];
}
}
divide_alpha = encode_buffer[encode_texel_index + premul_alpha_channel];
switch (decode)
{
case STBR__DECODE(STBR_TYPE_UINT8, STBR_COLORSPACE_LINEAR):
for (n = 0; n < channels; n++)
((unsigned char*)output_buffer)[output_texel_index + n] = (unsigned char)(stbr__saturate(encode_buffer[encode_texel_index + n]) * 255);
{
float divide_alpha_channel = (n == premul_alpha_channel) ? 1 : divide_alpha;
((unsigned char*)output_buffer)[output_texel_index + n] = (unsigned char)(stbr__saturate(encode_buffer[encode_texel_index + n] / divide_alpha_channel) * 255);
}
break;
case STBR__DECODE(STBR_TYPE_UINT8, STBR_COLORSPACE_SRGB):
for (n = 0; n < channels; n++)
((unsigned char*)output_buffer)[output_texel_index + n] = stbr__linear_uchar_to_srgb_uchar[(unsigned char)(stbr__saturate(encode_buffer[encode_texel_index + n]) * 255)];
{
float divide_alpha_channel = (n == premul_alpha_channel) ? 1 : divide_alpha;
((unsigned char*)output_buffer)[output_texel_index + n] = stbr__linear_uchar_to_srgb_uchar[(unsigned char)(stbr__saturate(encode_buffer[encode_texel_index + n] / divide_alpha_channel) * 255)];
}
break;
case STBR__DECODE(STBR_TYPE_UINT16, STBR_COLORSPACE_LINEAR):
for (n = 0; n < channels; n++)
((unsigned short*)output_buffer)[output_texel_index + n] = (unsigned short)(stbr__saturate(encode_buffer[encode_texel_index + n]) * 65535);
{
float divide_alpha_channel = (n == premul_alpha_channel) ? 1 : divide_alpha;
((unsigned short*)output_buffer)[output_texel_index + n] = (unsigned short)(stbr__saturate(encode_buffer[encode_texel_index + n] / divide_alpha_channel) * 65535);
}
break;
case STBR__DECODE(STBR_TYPE_UINT16, STBR_COLORSPACE_SRGB):
for (n = 0; n < channels; n++)
((unsigned short*)output_buffer)[output_texel_index + n] = (unsigned short)(stbr__linear_to_srgb(stbr__saturate(encode_buffer[encode_texel_index + n])) * 65535);
{
float divide_alpha_channel = (n == premul_alpha_channel) ? 1 : divide_alpha;
((unsigned short*)output_buffer)[output_texel_index + n] = (unsigned short)(stbr__linear_to_srgb(stbr__saturate(encode_buffer[encode_texel_index + n] / divide_alpha_channel)) * 65535);
}
break;
case STBR__DECODE(STBR_TYPE_UINT32, STBR_COLORSPACE_LINEAR):
for (n = 0; n < channels; n++)
((unsigned int*)output_buffer)[output_texel_index + n] = (unsigned int)(((double)stbr__saturate(encode_buffer[encode_texel_index + n])) * 4294967295);
{
float divide_alpha_channel = (n == premul_alpha_channel) ? 1 : divide_alpha;
((unsigned int*)output_buffer)[output_texel_index + n] = (unsigned int)(((double)stbr__saturate(encode_buffer[encode_texel_index + n] / divide_alpha_channel)) * 4294967295);
}
break;
case STBR__DECODE(STBR_TYPE_UINT32, STBR_COLORSPACE_SRGB):
for (n = 0; n < channels; n++)
((unsigned int*)output_buffer)[output_texel_index + n] = (unsigned int)(((double)stbr__linear_to_srgb(stbr__saturate(encode_buffer[encode_texel_index + n]))) * 4294967295);
{
float divide_alpha_channel = (n == premul_alpha_channel) ? 1 : divide_alpha;
((unsigned int*)output_buffer)[output_texel_index + n] = (unsigned int)(((double)stbr__linear_to_srgb(stbr__saturate(encode_buffer[encode_texel_index + n] / divide_alpha_channel))) * 4294967295);
}
break;
case STBR__DECODE(STBR_TYPE_FLOAT, STBR_COLORSPACE_LINEAR):
for (n = 0; n < channels; n++)
((float*)output_buffer)[output_texel_index + n] = stbr__saturate(encode_buffer[encode_texel_index + n]);
{
float divide_alpha_channel = (n == premul_alpha_channel) ? 1 : divide_alpha;
((float*)output_buffer)[output_texel_index + n] = stbr__saturate(encode_buffer[encode_texel_index + n] / divide_alpha_channel);
}
break;
case STBR__DECODE(STBR_TYPE_FLOAT, STBR_COLORSPACE_SRGB):
for (n = 0; n < channels; n++)
((float*)output_buffer)[output_texel_index + n] = stbr__linear_to_srgb(stbr__saturate(encode_buffer[encode_texel_index + n]));
{
float divide_alpha_channel = (n == premul_alpha_channel) ? 1 : divide_alpha;
((float*)output_buffer)[output_texel_index + n] = stbr__linear_to_srgb(stbr__saturate(encode_buffer[encode_texel_index + n] / divide_alpha_channel));
}
break;
default:
STBR_UNIMPLEMENTED("Unknown type/colorspace/channels combination.");
break;
}
// Put it back the way it was in case this is a ring buffer.
if (premul_alpha_channel)
{
for (n = 0; n < channels; n++)
{
if (n == premul_alpha_channel)
continue;
encode_buffer[encode_texel_index + n] *= encode_buffer[encode_texel_index + premul_alpha_channel];
}
}
}
static void stbr__resample_vertical_upsample(stbr__info* stbr_info, int n, int in_first_scanline, int in_last_scanline, float in_center_of_out)

4
tests/resample_test.cpp
Unescape View File

@ -295,8 +295,8 @@ void test_premul(const char* file)
stbi_write_png("test-output/premul-original.png", w, h, n, input_data, 0);
int new_w = (int)(w * .5);
int new_h = (int)(h * .5);
int new_w = (int)(w * .1);
int new_h = (int)(h * .1);
unsigned char* output_data = (unsigned char*)malloc(new_w * new_h * n * sizeof(unsigned char));

Write Preview
Loading…
Cancel
Save