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new quickstart docs;

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reformat docs;
new simple uint32 test
This commit is contained in:
Sean Barrett 2014-09-14 14:55:23 -07:00
parent 3c261481a6
commit 9f66b441bd
2 changed files with 163 additions and 117 deletions
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28
stb_image_resize.h
View File

@ -2,23 +2,33 @@
by Jorge L Rodriguez (@VinoBS) - 2014
http://github.com/nothings/stb
Written with emphasis on usage and speed. Only scaling is
currently supported, no rotations or translations.
DOCUMENTATION
Written with emphasis on usability, portability, and efficiency. (No
SIMD or threads, so it will not be the fastest implementation around.)
Only scaling is supported, no rotations or translations.
COMPILING & LINKING
In one C/C++ file that #includes this file, do this:
#define STB_IMAGE_RESIZE_IMPLEMENTATION
before the #include. That will create the implementation in that file.
VERY QUICK GUIDE
A typical resize of a in_w by in_h image to out_w by out_h with 4 channels where channel #3 is the alpha channel might look like:
int success = stbir_resize_uint8_srgb_edgemode(input_pixels, in_w, in_h, 0, output_pixels, out_w, out_h, 0, 4, 3, 0, STBIR_EDGE_CLAMP);
QUICKSTART
stbir_resize_uint8( input_pixels , in_w , in_h , 0,
output_pixels, out_w, out_h, 0, num_channels)
stbir_resize_float(...)
stbir_resize_uint8_srgb( input_pixels , in_w , in_h , 0,
output_pixels, out_w, out_h, 0,
num_channels , alpha_ chan , 0)
stbir_resize_uint8_srgb_edgemode(
input_pixels , in_w , in_h , 0,
output_pixels, out_w, out_h, 0,
num_channels , alpha_chan , 0, STBIR_EDGE_CLAMP)
WRAP/REFLECT/ZERO
FULL API
See the "header file" section of the source for API documentation.
ADDITIONAL DOCUMENTATION
MEMORY ALLOCATION
The resize functions here perform a single memory allocation using
malloc. To control the memory allocation, before the #include that
@ -149,13 +159,13 @@
#ifndef STBIR_INCLUDE_STB_IMAGE_RESIZE_H
#define STBIR_INCLUDE_STB_IMAGE_RESIZE_H
typedef unsigned char stbir_uint8;
#ifdef _MSC_VER
typedef unsigned char stbir_uint8;
typedef unsigned short stbir_uint16;
typedef unsigned int stbir_uint32;
#else
#include <stdint.h>
typedef uint8_t stbir_uint8;
typedef uint16_t stbir_uint16;
typedef uint32_t stbir_uint32;
#endif

36
tests/resample_test.cpp
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@ -750,6 +750,40 @@ void test_filters(void)
}
}
#define UMAX32 4294967295U
static void write32(char *filename, stbir_uint32 *output, int w, int h)
{
stbir_uint8 *data = (stbir_uint8*) malloc(w*h*3);
for (int i=0; i < w*h*3; ++i)
data[i] = output[i]>>24;
stbi_write_png(filename, w, h, 3, data, 0);
free(data);
}
static void test_32(void)
{
int w=100,h=120,x,y, out_w,out_h;
stbir_uint32 *input = (stbir_uint32*) malloc(4 * 3 * w * h);
stbir_uint32 *output = (stbir_uint32*) malloc(4 * 3 * 3*w * 3*h);
for (y=0; y < h; ++y) {
for (x=0; x < w; ++x) {
input[y*3*w + x*3 + 0] = x * ( UMAX32/w );
input[y*3*w + x*3 + 1] = y * ( UMAX32/h );
input[y*3*w + x*3 + 2] = UMAX32/2;
}
}
out_w = w*33/16;
out_h = h*33/16;
stbir_resize(input,w,h,0,output,out_w,out_h,0,STBIR_TYPE_UINT32,3,-1,0,STBIR_EDGE_CLAMP,STBIR_EDGE_CLAMP,STBIR_FILTER_DEFAULT,STBIR_FILTER_DEFAULT,STBIR_COLORSPACE_LINEAR,NULL);
write32("test-output/seantest_1.png", output,out_w,out_h);
out_w = w*16/33;
out_h = h*16/33;
stbir_resize(input,w,h,0,output,out_w,out_h,0,STBIR_TYPE_UINT32,3,-1,0,STBIR_EDGE_CLAMP,STBIR_EDGE_CLAMP,STBIR_FILTER_DEFAULT,STBIR_FILTER_DEFAULT,STBIR_COLORSPACE_LINEAR,NULL);
write32("test-output/seantest_2.png", output,out_w,out_h);
}
void test_suite(int argc, char **argv)
{
@ -758,6 +792,8 @@ void test_suite(int argc, char **argv)
_mkdir("test-output");
test_32();
if (argc > 1)
barbara = argv[1];
else