diff --git a/docs/stb_resample_ideas.txt b/docs/stb_resample_ideas.txt index a9842d3..0903ead 100644 --- a/docs/stb_resample_ideas.txt +++ b/docs/stb_resample_ideas.txt @@ -190,3 +190,12 @@ Cubic sampling function for seperable cubic: f(x) = 0 otherwise "a" is configurable, try -1/2 (from http://pixinsight.com/forum/index.php?topic=556.0 ) + + +Wish list: + s0, t0, s1, t1 vs scale_x, scale_y, offset_x, offset_y - What's the best interface? + Separate wrap modes and filter modes per axis + Alpha test coverage respecting resize (FloatImage::alphaTestCoverage and FloatImage::scaleAlphaToCoverage: https://code.google.com/p/nvidia-texture-tools/source/browse/trunk/src/nvimage/FloatImage.cpp) + Installable filter kernels + + diff --git a/stb_resample.h b/stb_resample.h new file mode 100644 index 0000000..9d2da3f --- /dev/null +++ b/stb_resample.h @@ -0,0 +1,1736 @@ +/* stb_resample - v0.50 - public domain image resampling + no warranty implied; use at your own risk + + Do this: + #define STB_RESAMPLE_IMPLEMENTATION + before you include this file in *one* C or C++ file to create the implementation. + + #define STBR_ASSERT(x) to avoid using assert.h. + + #define STBR_MALLOC and STBR_FREE to avoid using stdlib.h malloc. This will apply + to all functions except stbr_resize_arbitrary(), which doesn't allocate memory. + + QUICK NOTES: + Written with emphasis on usage and speed. Only the resize operation is + currently supported, no rotations or translations. + + Supports arbitrary resize for separable filters. For a list of + supported filters see the stbr_filter enum. To add a new filter, + write a filter function and add it to stbr__filter_info_table. + + Latest revisions: + 0.50 (2014-07-29) first released version + + See end of file for full revision history. + + TODO: + Installable filters + Specify wrap and filter modes independently for each axis + Resize that respects alpha test coverage + (Reference code: FloatImage::alphaTestCoverage and FloatImage::scaleAlphaToCoverage: + https://code.google.com/p/nvidia-texture-tools/source/browse/trunk/src/nvimage/FloatImage.cpp ) + + Initial implementation by Jorge L Rodriguez, @VinoBS +*/ + +#ifndef STBR_INCLUDE_STB_RESAMPLE_H +#define STBR_INCLUDE_STB_RESAMPLE_H + +// Basic usage: +// result = stbr_resize_uint8_srgb(input_data, input_w, input_h, output_data, output_w, output_h, channels, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP); +// * input_data is your supplied texels. +// * output_data will be the resized texels. It should be of size output_w * output_h * channels +// * Returned result is 1 for success or 0 in case of an error. In the case of an error an assert with be triggered, #define STBR_ASSERT() to see it. +// * If you're unsure of which filter to use, Catmull-Rom is a good upsampling filter and Mitchell is a good downsampling filter. +// +// +// Data types provided: uint8, uint16, uint32, float. +// +// +// Other function groups are provided, one for each data type, for more advanced functionality: +// +// stbr_resize_type_premultiply(input_data, input_w, input_h, output_data, output_w, output_h, channels, premultiply_alpha_channel, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB) +// * premultiply_alpha_channel - if nonzero, the specified channel will be multiplied into all other channels before resampling, then divided back out after. +// +// stbr_resize_type_subpixel(input_data, input_w, input_h, output_data, output_w, output_h, s0, t0, s1, t1, channels, filter, edge) +// * s0, t0, s1, t1 are the top-left and bottom right corner (uv addressing style: [0, 1]x[0, 1]) of a region of the input image to use. +// +// +// All functionality is offered in this function: +// +// result = stbr_resize_arbitrary(input_data, input_w, input_h, input_stride_in_bytes, +// output_data, output_w, output_h, output_stride_in_bytes, +// s0, t0, s1, t1, +// channels, premultiply_alpha_channel, STBR_TYPE_UINT8, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB); +// +// +// Control over memory allocation is offered like so: +// +// size_t memory_required = stbr_calculate_memory(input_w, input_h, output_w, output_h, s0, t0, s1, t1, channels, STBR_FILTER_CATMULLROM); +// void* extra_memory = malloc(memory_required); // Any memory allocation method of your choosing +// result = stbr_resize_advanced(input_data, input_w, input_h, input_stride_in_bytes, +// output_data, output_w, output_h, output_stride_in_bytes, +// s0, t0, s1, t1, +// channels, premultiply_alpha_channel, STBR_TYPE_UINT8, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, +// extra_memory, memory_required); +// free(extra_memory); +// +// * input_stride_in_bytes and output_stride_in_bytes can be 0. If so they will be automatically calculated as width * channels. +// * s0, t0, s1, t1 are the top-left and bottom right corner (uv addressing style: [0, 1]x[0, 1]) of a region of the input image to use. +// * premultiply_alpha_channel - if nonzero, the specified channel will be multiplied into all other channels before resampling, then divided back out after. +// * Returned result is 1 for success or 0 in case of an error. In the case of an error an assert with be triggered, #define STBR_ASSERT() to see it. +// * stbr_resize_advanced() will not allocate any memory, it will use the memory you pass in to do its work. Memory required grows +// approximately linearly with input and output size, but with discontinuities at input_w == output_w and input_h == output_height. +// stbr_calculate_memory() is deterministic on its inputs. + + +typedef enum +{ + STBR_FILTER_NEAREST = 1, + STBR_FILTER_BILINEAR = 2, + STBR_FILTER_BICUBIC = 3, // A cubic b spline + STBR_FILTER_CATMULLROM = 4, + STBR_FILTER_MITCHELL = 5, +} stbr_filter; + +typedef enum +{ + STBR_EDGE_CLAMP = 1, + STBR_EDGE_REFLECT = 2, + STBR_EDGE_WRAP = 3, +} stbr_edge; + +typedef enum +{ + STBR_COLORSPACE_LINEAR = 1, + STBR_COLORSPACE_SRGB = 2, + // If you add here, update STBR_MAX_COLORSPACES +} stbr_colorspace; + +#define STBR_MAX_COLORSPACES 2 + +typedef enum +{ + STBR_TYPE_UINT8 = 1, + STBR_TYPE_UINT16 = 2, + STBR_TYPE_UINT32 = 3, + STBR_TYPE_FLOAT = 4, + // If you add here, update STBR_MAX_TYPES and stbr__type_size +} stbr_type; + +#define STBR_MAX_TYPES 4 + +typedef unsigned char stbr_uint8; + +#ifdef _MSC_VER +typedef unsigned short stbr_uint16; +typedef unsigned int stbr_uint32; +#else +#include +typedef uint16_t stbr_uint16; +typedef uint32_t stbr_uint32; +#endif + +typedef unsigned int stbr_size_t; // to avoid including a header for size_t + +#ifdef __cplusplus +extern "C" { +#endif + +#ifdef STB_RESAMPLE_STATIC +#define STBRDEF static +#else +#define STBRDEF extern +#endif + + ////////////////////////////////////////////////////////////////////////////// + // + // PRIMARY API - sRGB type-safe image resizing. + // + + STBRDEF int stbr_resize_uint8_srgb(const stbr_uint8* input_data, int input_w, int input_h, + stbr_uint8* output_data, int output_w, int output_h, + int channels, stbr_filter filter, stbr_edge edge); + + STBRDEF int stbr_resize_uint16_srgb(const stbr_uint16* input_data, int input_w, int input_h, + stbr_uint16* output_data, int output_w, int output_h, + int channels, stbr_filter filter, stbr_edge edge); + + STBRDEF int stbr_resize_uint32_srgb(const stbr_uint32* input_data, int input_w, int input_h, + stbr_uint32* output_data, int output_w, int output_h, + int channels, stbr_filter filter, stbr_edge edge); + + STBRDEF int stbr_resize_float_srgb(const float* input_data, int input_w, int input_h, + float* output_data, int output_w, int output_h, + int channels, stbr_filter filter, stbr_edge edge); + + + STBRDEF int stbr_resize_uint8_premultiply(const stbr_uint8* input_data, int input_w, int input_h, + stbr_uint8* output_data, int output_w, int output_h, + int channels, int premultiply_alpha_channel, stbr_filter filter, stbr_edge edge, stbr_colorspace colorspace); + + STBRDEF int stbr_resize_uint16_premultiply(const stbr_uint16* input_data, int input_w, int input_h, + stbr_uint16* output_data, int output_w, int output_h, + int channels, int premultiply_alpha_channel, stbr_filter filter, stbr_edge edge, stbr_colorspace colorspace); + + STBRDEF int stbr_resize_uint32_premultiply(const stbr_uint32* input_data, int input_w, int input_h, + stbr_uint32* output_data, int output_w, int output_h, + int channels, int premultiply_alpha_channel, stbr_filter filter, stbr_edge edge, stbr_colorspace colorspace); + + STBRDEF int stbr_resize_float_premultiply(const float* input_data, int input_w, int input_h, + float* output_data, int output_w, int output_h, + int channels, int premultiply_alpha_channel, stbr_filter filter, stbr_edge edge, stbr_colorspace colorspace); + + + STBRDEF int stbr_resize_uint8_subpixel(const stbr_uint8* input_data, int input_w, int input_h, + stbr_uint8* output_data, int output_w, int output_h, + float s0, float t0, float s1, float t1, + int channels, stbr_filter filter, stbr_edge edge); + + STBRDEF int stbr_resize_uint16_subpixel(const stbr_uint16* input_data, int input_w, int input_h, + stbr_uint16* output_data, int output_w, int output_h, + float s0, float t0, float s1, float t1, + int channels, stbr_filter filter, stbr_edge edge); + + STBRDEF int stbr_resize_uint32_subpixel(const stbr_uint32* input_data, int input_w, int input_h, + stbr_uint32* output_data, int output_w, int output_h, + float s0, float t0, float s1, float t1, + int channels, stbr_filter filter, stbr_edge edge); + + STBRDEF int stbr_resize_float_subpixel(const float* input_data, int input_w, int input_h, + float* output_data, int output_w, int output_h, + float s0, float t0, float s1, float t1, + int channels, stbr_filter filter, stbr_edge edge); + + + STBRDEF int stbr_resize_arbitrary(const void* input_data, int input_w, int input_h, int input_stride_in_bytes, + void* output_data, int output_w, int output_h, int output_stride_in_bytes, + float s0, float t0, float s1, float t1, + int channels, int premultiply_alpha_channel, stbr_type type, stbr_filter filter, stbr_edge edge, stbr_colorspace colorspace); + + + ////////////////////////////////////////////////////////////////////////////// + // + // ADVANCED API + // + + STBRDEF stbr_size_t stbr_calculate_memory(int input_w, int input_h, int output_w, int output_h, float s0, float t0, float s1, float t1, int channels, stbr_filter filter); + + STBRDEF int stbr_resize_advanced(const void* input_data, int input_w, int input_h, int input_stride_in_bytes, + void* output_data, int output_w, int output_h, int output_stride_in_bytes, + float s0, float t0, float s1, float t1, + int channels, int premultiply_alpha_channel, stbr_type type, stbr_filter filter, stbr_edge edge, stbr_colorspace colorspace, + void* tempmem, stbr_size_t tempmem_size_in_bytes); + + +#ifdef __cplusplus +} +#endif + +// +// +//// end header file ///////////////////////////////////////////////////// +#endif // STBR_INCLUDE_STB_RESAMPLE_H + +#ifdef STB_RESAMPLE_IMPLEMENTATION + +#ifndef STBR_ASSERT +#include +#define STBR_ASSERT(x) assert(x) +#endif + +#ifdef STBR_DEBUG +#define STBR_DEBUG_ASSERT STBR_ASSERT +#else +#define STBR_DEBUG_ASSERT +#endif + +// If you hit this it means I haven't done it yet. +#define STBR_UNIMPLEMENTED(x) STBR_ASSERT(!(x)) + + +// For memset +#include + +#include + +#ifndef STBR_MALLOC +#include + +#define STBR_MALLOC malloc +#define STBR_FREE free +#endif + + +#ifndef _MSC_VER +#ifdef __cplusplus +#define stbr_inline inline +#else +#define stbr_inline +#endif +#else +#define stbr_inline __forceinline +#endif + + +// should produce compiler error if size is wrong +typedef unsigned char stbr__validate_uint32[sizeof(stbr_uint32) == 4 ? 1 : -1]; + +#ifdef _MSC_VER +#define STBR_NOTUSED(v) (void)(v) +#else +#define STBR_NOTUSED(v) (void)sizeof(v) +#endif + +#define STBR_ARRAY_SIZE(a) (sizeof((a))/sizeof((a)[0])) + +#define STBR__MAX_UNROLLED_CHANNELS 4 + +// Kernel function centered at 0 +typedef float (stbr__kernel_fn)(float x); + +typedef struct +{ + stbr__kernel_fn* kernel; + float support; +} stbr__filter_info; + +// When upsampling, the contributors are which source texels contribute. +// When downsampling, the contributors are which destination texels are contributed to. +typedef struct +{ + int n0; // First contributing texel + int n1; // Last contributing texel +} stbr__contributors; + +typedef struct +{ + const void* input_data; + int input_w; + int input_h; + int input_stride_bytes; + + void* output_data; + int output_w; + int output_h; + int output_stride_bytes; + + float s0, t0, s1, t1; + + float horizontal_shift; // Units: output texels + float vertical_shift; // Units: output texels + float horizontal_scale; + float vertical_scale; + + int channels; + int premul_alpha_channel; + stbr_type type; + stbr_filter filter; + stbr_edge edge; + stbr_colorspace colorspace; + + stbr__contributors* horizontal_contributors; + float* horizontal_coefficients; + + stbr__contributors vertical_contributors; + float* vertical_coefficients; + + int decode_buffer_texels; + float* decode_buffer; + + float* horizontal_buffer; + + int ring_buffer_length_bytes; // The length of an individual entry in the ring buffer. The total number of ring buffers is stbr__get_filter_texel_width(filter) + int ring_buffer_first_scanline; + int ring_buffer_last_scanline; + int ring_buffer_begin_index; + float* ring_buffer; + + float* encode_buffer; // A temporary buffer to store floats so we don't lose precision while we do multiply-adds. +} stbr__info; + + +static stbr_inline int stbr__min(int a, int b) +{ + return a < b ? a : b; +} + +static stbr_inline int stbr__max(int a, int b) +{ + return a > b ? a : b; +} + +static stbr_inline float stbr__saturate(float x) +{ + if (x < 0) + return 0; + + if (x > 1) + return 1; + + return x; +} + +static float stbr__srgb_uchar_to_linear_float[256] = { + 0.000000f, 0.000304f, 0.000607f, 0.000911f, 0.001214f, 0.001518f, 0.001821f, 0.002125f, 0.002428f, 0.002732f, 0.003035f, 0.003347f, 0.003677f, 0.004025f, 0.004391f, 0.004777f, 0.005182f, 0.005605f, 0.006049f, 0.006512f, 0.006995f, 0.007499f, 0.008023f, 0.008568f, 0.009134f, 0.009721f, 0.010330f, 0.010960f, 0.011612f, 0.012286f, 0.012983f, 0.013702f, 0.014444f, 0.015209f, 0.015996f, 0.016807f, 0.017642f, 0.018500f, 0.019382f, 0.020289f, 0.021219f, 0.022174f, 0.023153f, 0.024158f, 0.025187f, 0.026241f, 0.027321f, 0.028426f, 0.029557f, 0.030713f, 0.031896f, 0.033105f, 0.034340f, 0.035601f, 0.036889f, 0.038204f, 0.039546f, 0.040915f, 0.042311f, 0.043735f, 0.045186f, 0.046665f, 0.048172f, 0.049707f, 0.051269f, 0.052861f, 0.054480f, 0.056128f, 0.057805f, 0.059511f, 0.061246f, 0.063010f, 0.064803f, 0.066626f, 0.068478f, 0.070360f, 0.072272f, 0.074214f, 0.076185f, 0.078187f, 0.080220f, 0.082283f, 0.084376f, 0.086500f, 0.088656f, 0.090842f, 0.093059f, 0.095307f, 0.097587f, 0.099899f, 0.102242f, 0.104616f, 0.107023f, 0.109462f, 0.111932f, 0.114435f, 0.116971f, 0.119538f, 0.122139f, 0.124772f, 0.127438f, 0.130136f, 0.132868f, 0.135633f, 0.138432f, 0.141263f, 0.144128f, 0.147027f, 0.149960f, 0.152926f, 0.155926f, 0.158961f, 0.162029f, 0.165132f, 0.168269f, 0.171441f, 0.174647f, 0.177888f, 0.181164f, 0.184475f, 0.187821f, 0.191202f, 0.194618f, 0.198069f, 0.201556f, 0.205079f, 0.208637f, 0.212231f, 0.215861f, 0.219526f, 0.223228f, 0.226966f, 0.230740f, 0.234551f, 0.238398f, 0.242281f, 0.246201f, 0.250158f, 0.254152f, 0.258183f, 0.262251f, 0.266356f, 0.270498f, 0.274677f, 0.278894f, 0.283149f, 0.287441f, 0.291771f, 0.296138f, 0.300544f, 0.304987f, 0.309469f, 0.313989f, 0.318547f, 0.323143f, 0.327778f, 0.332452f, 0.337164f, 0.341914f, 0.346704f, 0.351533f, 0.356400f, 0.361307f, 0.366253f, 0.371238f, 0.376262f, 0.381326f, 0.386430f, 0.391573f, 0.396755f, 0.401978f, 0.407240f, 0.412543f, 0.417885f, 0.423268f, 0.428691f, 0.434154f, 0.439657f, 0.445201f, 0.450786f, 0.456411f, 0.462077f, 0.467784f, 0.473532f, 0.479320f, 0.485150f, 0.491021f, 0.496933f, 0.502887f, 0.508881f, 0.514918f, 0.520996f, 0.527115f, 0.533276f, 0.539480f, 0.545725f, 0.552011f, 0.558340f, 0.564712f, 0.571125f, 0.577581f, 0.584078f, 0.590619f, 0.597202f, 0.603827f, 0.610496f, 0.617207f, 0.623960f, 0.630757f, 0.637597f, 0.644480f, 0.651406f, 0.658375f, 0.665387f, 0.672443f, 0.679543f, 0.686685f, 0.693872f, 0.701102f, 0.708376f, 0.715694f, 0.723055f, 0.730461f, 0.737911f, 0.745404f, 0.752942f, 0.760525f, 0.768151f, 0.775822f, 0.783538f, 0.791298f, 0.799103f, 0.806952f, 0.814847f, 0.822786f, 0.830770f, 0.838799f, 0.846873f, 0.854993f, 0.863157f, 0.871367f, 0.879622f, 0.887923f, 0.896269f, 0.904661f, 0.913099f, 0.921582f, 0.930111f, 0.938686f, 0.947307f, 0.955974f, 0.964686f, 0.973445f, 0.982251f, 0.991102f, 1.0f +}; + +static unsigned char stbr__linear_uchar_to_srgb_uchar[256] = { + 0, 12, 21, 28, 33, 38, 42, 46, 49, 52, 55, 58, 61, 63, 66, 68, 70, 73, 75, 77, 79, 81, 82, 84, 86, 88, 89, 91, 93, 94, 96, 97, 99, 100, 102, 103, 104, 106, 107, 109, 110, 111, 112, 114, 115, 116, 117, 118, 120, 121, 122, 123, 124, 125, 126, 127, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 151, 152, 153, 154, 155, 156, 157, 157, 158, 159, 160, 161, 161, 162, 163, 164, 165, 165, 166, 167, 168, 168, 169, 170, 171, 171, 172, 173, 174, 174, 175, 176, 176, 177, 178, 179, 179, 180, 181, 181, 182, 183, 183, 184, 185, 185, 186, 187, 187, 188, 189, 189, 190, 191, 191, 192, 193, 193, 194, 194, 195, 196, 196, 197, 197, 198, 199, 199, 200, 201, 201, 202, 202, 203, 204, 204, 205, 205, 206, 206, 207, 208, 208, 209, 209, 210, 210, 211, 212, 212, 213, 213, 214, 214, 215, 215, 216, 217, 217, 218, 218, 219, 219, 220, 220, 221, 221, 222, 222, 223, 223, 224, 224, 225, 226, 226, 227, 227, 228, 228, 229, 229, 230, 230, 231, 231, 232, 232, 233, 233, 234, 234, 235, 235, 236, 236, 237, 237, 237, 238, 238, 239, 239, 240, 240, 241, 241, 242, 242, 243, 243, 244, 244, 245, 245, 245, 246, 246, 247, 247, 248, 248, 249, 249, 250, 250, 251, 251, 251, 252, 252, 253, 253, 254, 254, 255 +}; + +static unsigned char stbr__type_size[] = { + 0, + 1, // STBR_TYPE_UINT8 + 2, // STBR_TYPE_UINT16 + 4, // STBR_TYPE_UINT32 + 4, // STBR_TYPE_FLOAT +}; + +float stbr__srgb_to_linear(float f) +{ + if (f <= 0.04045f) + return f / 12.92f; + else + return (float)pow((f + 0.055f) / 1.055f, 2.4f); +} + +float stbr__linear_to_srgb(float f) +{ + if (f <= 0.0031308f) + return f * 12.92f; + else + return 1.055f * (float)pow(f, 1 / 2.4f) - 0.055f; +} + + + +static float stbr__filter_nearest(float x) +{ + if (x <= -0.5f) + return 0; + else if (x > 0.5f) + return 0; + else + return 1; +} + +static float stbr__filter_bilinear(float x) +{ + x = (float)fabs(x); + + if (x <= 1.0f) + return 1 - x; + else + return 0; +} + +static float stbr__filter_bicubic(float x) +{ + x = (float)fabs(x); + + if (x < 1.0f) + return 0.66666666666f + x*x*(0.5f*x - 1); + else if (x < 2.0f) + return 1.3333333333f + x*(-2 + x*(1 - 0.16666666f * x)); + + return (0.0f); +} + +static float stbr__filter_catmullrom(float x) +{ + x = (float)fabs(x); + + if (x < 1.0f) + return 1 - x*x*(2.5f - 1.5f*x); + else if (x < 2.0f) + return 2 - x*(4 + x*(0.5f*x - 2.5f)); + + return (0.0f); +} + +static float stbr__filter_mitchell(float x) +{ + x = (float)fabs(x); + + if (x < 1.0f) + return 0.8888888888f + x*x*(1.1666666666666f * x - 2.0f); + else if (x < 2.0f) + return 1.777777777777f + x*(-3.3333333333f + x*(2 - 0.3888888888888f*x)); + + return (0.0f); +} + +static stbr__filter_info stbr__filter_info_table[] = { + { NULL, 0.0f }, + { stbr__filter_nearest, 0.5f }, + { stbr__filter_bilinear, 1.0f }, + { stbr__filter_bicubic, 2.0f }, + { stbr__filter_catmullrom, 2.0f }, + { stbr__filter_mitchell, 2.0f }, +}; + +stbr_inline static int stbr__use_upsampling(float ratio) +{ + return ratio > 1; +} + +stbr_inline static int stbr__use_width_upsampling(stbr__info* stbr_info) +{ + return stbr__use_upsampling(stbr_info->horizontal_scale); +} + +stbr_inline static int stbr__use_height_upsampling(stbr__info* stbr_info) +{ + return stbr__use_upsampling(stbr_info->vertical_scale); +} + +// This is the maximum number of input samples that can affect an output sample +// with the given filter +stbr_inline static int stbr__get_filter_texel_width(stbr_filter filter, int input_w, int output_w, float scale) +{ + STBR_ASSERT(filter != 0); + STBR_ASSERT(filter < STBR_ARRAY_SIZE(stbr__filter_info_table)); + + if (stbr__use_upsampling(scale)) + return (int)ceil(stbr__filter_info_table[filter].support * 2); + else + return (int)ceil(stbr__filter_info_table[filter].support * 2 / scale); +} + +stbr_inline static int stbr__get_filter_texel_width_horizontal(stbr__info* stbr_info) +{ + return stbr__get_filter_texel_width(stbr_info->filter, stbr_info->input_w, stbr_info->output_w, stbr_info->horizontal_scale); +} + +stbr_inline static int stbr__get_filter_texel_width_vertical(stbr__info* stbr_info) +{ + return stbr__get_filter_texel_width(stbr_info->filter, stbr_info->input_h, stbr_info->output_h, stbr_info->vertical_scale); +} + +// This is how much to expand buffers to account for filters seeking outside +// the image boundaries. +stbr_inline static int stbr__get_filter_texel_margin(stbr_filter filter, int input_w, int output_w, float scale) +{ + return stbr__get_filter_texel_width(filter, input_w, output_w, scale) / 2; +} + +stbr_inline static int stbr__get_filter_texel_margin_horizontal(stbr__info* stbr_info) +{ + return stbr__get_filter_texel_width(stbr_info->filter, stbr_info->input_w, stbr_info->output_w, stbr_info->horizontal_scale) / 2; +} + +stbr_inline static int stbr__get_filter_texel_margin_vertical(stbr__info* stbr_info) +{ + return stbr__get_filter_texel_width(stbr_info->filter, stbr_info->input_h, stbr_info->output_h, stbr_info->vertical_scale) / 2; +} + +stbr_inline static int stbr__get_horizontal_contributors_noinfo(stbr_filter filter, int input_w, int output_w, float horizontal_scale) +{ + if (stbr__use_upsampling(horizontal_scale)) + return output_w; + else + return (input_w + stbr__get_filter_texel_margin(filter, input_w, output_w, horizontal_scale) * 2); +} + +stbr_inline static int stbr__get_horizontal_contributors(stbr__info* stbr_info) +{ + return stbr__get_horizontal_contributors_noinfo(stbr_info->filter, stbr_info->input_w, stbr_info->output_w, stbr_info->horizontal_scale); +} + +stbr_inline static int stbr__get_total_coefficients_noinfo(stbr_filter filter, int input_w, int output_w, float horizontal_scale) +{ + return stbr__get_horizontal_contributors_noinfo(filter, input_w, output_w, horizontal_scale) * stbr__get_filter_texel_width(filter, input_w, output_w, horizontal_scale); +} + +stbr_inline static int stbr__get_total_coefficients(stbr__info* stbr_info) +{ + return stbr__get_total_coefficients_noinfo(stbr_info->filter, stbr_info->input_w, stbr_info->output_w, stbr_info->horizontal_scale); +} + +stbr_inline static stbr__contributors* stbr__get_contributor(stbr__info* stbr_info, int n) +{ + STBR_DEBUG_ASSERT(n >= 0 && n < stbr__get_horizontal_contributors(stbr_info)); + return &stbr_info->horizontal_contributors[n]; +} + +stbr_inline static float* stbr__get_coefficient(stbr__info* stbr_info, int n, int c) +{ + return &stbr_info->horizontal_coefficients[stbr__get_filter_texel_width(stbr_info->filter, stbr_info->input_w, stbr_info->output_w, stbr_info->horizontal_scale)*n + c]; +} + +stbr_inline static int stbr__edge_wrap(stbr_edge edge, int n, int max) +{ + switch (edge) + { + case STBR_EDGE_CLAMP: + if (n < 0) + return 0; + + if (n >= max) + return max - 1; + + return n; + + case STBR_EDGE_REFLECT: + { + if (n < 0) + { + if (n < max) + return -n; + else + return max - 1; + } + + if (n >= max) + { + int max2 = max * 2; + if (n >= max2) + return 0; + else + return max2 - n - 1; + } + + return n; + } + + case STBR_EDGE_WRAP: + if (n >= 0) + return (n % max); + else + { + int m = (-n) % max; + + if (m != 0) + m = max - m; + + return (m); + } + + default: + STBR_UNIMPLEMENTED("Unimplemented edge type"); + return 0; + } +} + +// What input texels contribute to this output texel? +static void stbr__calculate_sample_range_upsample(int n, float out_filter_radius, float scale_ratio, float out_shift, int* in_first_texel, int* in_last_texel, float* in_center_of_out) +{ + float out_texel_center = (float)n + 0.5f; + float out_texel_influence_lowerbound = out_texel_center - out_filter_radius; + float out_texel_influence_upperbound = out_texel_center + out_filter_radius; + + float in_texel_influence_lowerbound = (out_texel_influence_lowerbound + out_shift) / scale_ratio; + float in_texel_influence_upperbound = (out_texel_influence_upperbound + out_shift) / scale_ratio; + + *in_center_of_out = (out_texel_center + out_shift) / scale_ratio; + *in_first_texel = (int)(floor(in_texel_influence_lowerbound + 0.5)); + *in_last_texel = (int)(floor(in_texel_influence_upperbound - 0.5)); +} + +// What output texels does this input texel contribute to? +static void stbr__calculate_sample_range_downsample(int n, float in_pixels_radius, float scale_ratio, float out_shift, int* out_first_texel, int* out_last_texel, float* out_center_of_in) +{ + float in_texel_center = (float)n + 0.5f; + float in_texel_influence_lowerbound = in_texel_center - in_pixels_radius; + float in_texel_influence_upperbound = in_texel_center + in_pixels_radius; + + float out_texel_influence_lowerbound = in_texel_influence_lowerbound * scale_ratio - out_shift; + float out_texel_influence_upperbound = in_texel_influence_upperbound * scale_ratio - out_shift; + + *out_center_of_in = in_texel_center * scale_ratio - out_shift; + *out_first_texel = (int)(floor(out_texel_influence_lowerbound + 0.5)); + *out_last_texel = (int)(floor(out_texel_influence_upperbound - 0.5)); +} + +static void stbr__calculate_coefficients_upsample(stbr__info* stbr_info, int in_first_texel, int in_last_texel, float in_center_of_out, stbr__contributors* contributor, float* coefficient_group) +{ + int i; + float total_filter = 0; + float filter_scale; + stbr_filter filter = stbr_info->filter; + + STBR_DEBUG_ASSERT(in_last_texel - in_first_texel <= stbr__get_filter_texel_width_horizontal(stbr_info)); + + contributor->n0 = in_first_texel; + contributor->n1 = in_last_texel; + + STBR_DEBUG_ASSERT(contributor->n1 >= contributor->n0); + + for (i = 0; i <= in_last_texel - in_first_texel; i++) + { + float in_texel_center = (float)(i + in_first_texel) + 0.5f; + total_filter += coefficient_group[i] = stbr__filter_info_table[filter].kernel(in_center_of_out - in_texel_center); + } + + STBR_DEBUG_ASSERT(total_filter > 0.9); + STBR_DEBUG_ASSERT(total_filter < 1.1f); // Make sure it's not way off. + + // Make sure the sum of all coefficients is 1. + filter_scale = 1 / total_filter; + + for (i = 0; i <= in_last_texel - in_first_texel; i++) + coefficient_group[i] *= filter_scale; +} + +static void stbr__calculate_coefficients_downsample(stbr__info* stbr_info, float scale_ratio, int out_first_texel, int out_last_texel, float out_center_of_in, stbr__contributors* contributor, float* coefficient_group) +{ + int i; + stbr_filter filter = stbr_info->filter; + + STBR_DEBUG_ASSERT(out_last_texel - out_first_texel <= stbr__get_filter_texel_width_horizontal(stbr_info)); + + contributor->n0 = out_first_texel; + contributor->n1 = out_last_texel; + + STBR_DEBUG_ASSERT(contributor->n1 >= contributor->n0); + + for (i = 0; i <= out_last_texel - out_first_texel; i++) + { + float in_texel_center = (float)(i + out_first_texel) + 0.5f; + coefficient_group[i] = stbr__filter_info_table[filter].kernel((out_center_of_in - in_texel_center)/scale_ratio); + } +} + +#ifdef STBR_DEBUG +static void stbr__check_downsample_coefficients(stbr__info* stbr_info) +{ + int i; + for (i = 0; i < stbr_info->output_w; i++) + { + float total = 0; + int j; + for (j = 0; j < stbr__get_horizontal_contributors(stbr_info); j++) + { + if (i >= stbr_info->horizontal_contributors[j].n0 && i <= stbr_info->horizontal_contributors[j].n1) + { + float coefficient = *stbr__get_coefficient(stbr_info, j, i - stbr_info->horizontal_contributors[j].n0); + total += coefficient; + } + else if (i < stbr_info->horizontal_contributors[j].n0) + break; + } + + STBR_DEBUG_ASSERT(total > 0.9f); + STBR_DEBUG_ASSERT(total <= 1.0f + 1.0f / (pow(2.0f, 8.0f * stbr__type_size[stbr_info->type]) - 1)); + } +} +#endif + +// Each scan line uses the same kernel values so we should calculate the kernel +// values once and then we can use them for every scan line. +static void stbr__calculate_horizontal_filters(stbr__info* stbr_info) +{ + int n; + float scale_ratio = stbr_info->horizontal_scale; + + int total_contributors = stbr__get_horizontal_contributors(stbr_info); + + if (stbr__use_width_upsampling(stbr_info)) + { + float out_pixels_radius = stbr__filter_info_table[stbr_info->filter].support * scale_ratio; + + // Looping through out texels + for (n = 0; n < total_contributors; n++) + { + float in_center_of_out; // Center of the current out texel in the in texel space + int in_first_texel, in_last_texel; + + stbr__calculate_sample_range_upsample(n, out_pixels_radius, scale_ratio, stbr_info->horizontal_shift, &in_first_texel, &in_last_texel, &in_center_of_out); + + stbr__calculate_coefficients_upsample(stbr_info, in_first_texel, in_last_texel, in_center_of_out, stbr__get_contributor(stbr_info, n), stbr__get_coefficient(stbr_info, n, 0)); + } + } + else + { + float in_pixels_radius = stbr__filter_info_table[stbr_info->filter].support / scale_ratio; + + // Looping through in texels + for (n = 0; n < total_contributors; n++) + { + float out_center_of_in; // Center of the current out texel in the in texel space + int out_first_texel, out_last_texel; + int n_adjusted = n - stbr__get_filter_texel_margin_horizontal(stbr_info); + + stbr__calculate_sample_range_downsample(n_adjusted, in_pixels_radius, scale_ratio, stbr_info->horizontal_shift, &out_first_texel, &out_last_texel, &out_center_of_in); + + stbr__calculate_coefficients_downsample(stbr_info, scale_ratio, out_first_texel, out_last_texel, out_center_of_in, stbr__get_contributor(stbr_info, n), stbr__get_coefficient(stbr_info, n, 0)); + } + +#ifdef STBR_DEBUG + stbr__check_downsample_coefficients(stbr_info); +#endif + } +} + +static float* stbr__get_decode_buffer(stbr__info* stbr_info) +{ + // The 0 index of the decode buffer starts after the margin. This makes + // it okay to use negative indexes on the decode buffer. + return &stbr_info->decode_buffer[stbr__get_filter_texel_margin_horizontal(stbr_info) * stbr_info->channels]; +} + +#define STBR__DECODE(type, colorspace) ((type) * (STBR_MAX_COLORSPACES) + (colorspace)) + +static void stbr__decode_scanline(stbr__info* stbr_info, int n) +{ + int x, c; + int channels = stbr_info->channels; + int premul_alpha_channel = stbr_info->premul_alpha_channel; + int type = stbr_info->type; + int colorspace = stbr_info->colorspace; + int input_w = stbr_info->input_w; + int input_stride = stbr_info->input_stride_bytes / stbr__type_size[stbr_info->type]; + const void* input_data = stbr_info->input_data; + float* decode_buffer = stbr__get_decode_buffer(stbr_info); + stbr_edge edge = stbr_info->edge; + int in_buffer_row_index = stbr__edge_wrap(edge, n, stbr_info->input_h) * input_stride; + int max_x = input_w + stbr__get_filter_texel_margin_horizontal(stbr_info); + int decode = STBR__DECODE(type, colorspace); + + for (x = -stbr__get_filter_texel_margin_horizontal(stbr_info); x < max_x; x++) + { + int decode_texel_index = x * channels; + int input_texel_index = in_buffer_row_index + stbr__edge_wrap(edge, x, input_w) * channels; + + switch (decode) + { + case STBR__DECODE(STBR_TYPE_UINT8, STBR_COLORSPACE_LINEAR): + for (c = 0; c < channels; c++) + decode_buffer[decode_texel_index + c] = ((float)((const unsigned char*)input_data)[input_texel_index + c]) / 255; + break; + + case STBR__DECODE(STBR_TYPE_UINT8, STBR_COLORSPACE_SRGB): + for (c = 0; c < channels; c++) + decode_buffer[decode_texel_index + c] = stbr__srgb_uchar_to_linear_float[((const unsigned char*)input_data)[input_texel_index + c]]; + break; + + case STBR__DECODE(STBR_TYPE_UINT16, STBR_COLORSPACE_LINEAR): + for (c = 0; c < channels; c++) + decode_buffer[decode_texel_index + c] = ((float)((const unsigned short*)input_data)[input_texel_index + c]) / 65535; + break; + + case STBR__DECODE(STBR_TYPE_UINT16, STBR_COLORSPACE_SRGB): + for (c = 0; c < channels; c++) + decode_buffer[decode_texel_index + c] = stbr__srgb_to_linear(((float)((const unsigned short*)input_data)[input_texel_index + c]) / 65535); + break; + + case STBR__DECODE(STBR_TYPE_UINT32, STBR_COLORSPACE_LINEAR): + for (c = 0; c < channels; c++) + decode_buffer[decode_texel_index + c] = (float)(((double)((const unsigned int*)input_data)[input_texel_index + c]) / 4294967295); + break; + + case STBR__DECODE(STBR_TYPE_UINT32, STBR_COLORSPACE_SRGB): + for (c = 0; c < channels; c++) + decode_buffer[decode_texel_index + c] = stbr__srgb_to_linear((float)(((double)((const unsigned int*)input_data)[input_texel_index + c]) / 4294967295)); + break; + + case STBR__DECODE(STBR_TYPE_FLOAT, STBR_COLORSPACE_LINEAR): + for (c = 0; c < channels; c++) + decode_buffer[decode_texel_index + c] = ((const float*)input_data)[input_texel_index + c]; + break; + + case STBR__DECODE(STBR_TYPE_FLOAT, STBR_COLORSPACE_SRGB): + for (c = 0; c < channels; c++) + decode_buffer[decode_texel_index + c] = stbr__srgb_to_linear(((const float*)input_data)[input_texel_index + c]); + break; + + default: + STBR_UNIMPLEMENTED("Unknown type/colorspace/channels combination."); + break; + } + + if (premul_alpha_channel) + { + for (c = 0; c < channels; c++) + { + if (c == premul_alpha_channel) + continue; + + decode_buffer[decode_texel_index + c] *= decode_buffer[decode_texel_index + premul_alpha_channel]; + } + } + } +} + +static float* stbr__get_ring_buffer_entry(float* ring_buffer, int index, int ring_buffer_length) +{ + return &ring_buffer[index * ring_buffer_length]; +} + +static float* stbr__add_empty_ring_buffer_entry(stbr__info* stbr_info, int n) +{ + int ring_buffer_index; + float* ring_buffer; + + if (stbr_info->ring_buffer_begin_index < 0) + { + ring_buffer_index = stbr_info->ring_buffer_begin_index = 0; + stbr_info->ring_buffer_first_scanline = n; + } + else + { + ring_buffer_index = (stbr_info->ring_buffer_begin_index + (stbr_info->ring_buffer_last_scanline - stbr_info->ring_buffer_first_scanline) + 1) % stbr__get_filter_texel_width_vertical(stbr_info); + STBR_DEBUG_ASSERT(ring_buffer_index != stbr_info->ring_buffer_begin_index); + } + + ring_buffer = stbr__get_ring_buffer_entry(stbr_info->ring_buffer, ring_buffer_index, stbr_info->ring_buffer_length_bytes / sizeof(float)); + memset(ring_buffer, 0, stbr_info->ring_buffer_length_bytes); + + stbr_info->ring_buffer_last_scanline = n; + + return ring_buffer; +} + + +static void stbr__resample_horizontal_upsample(stbr__info* stbr_info, int n, float* output_buffer) +{ + int x, k; + int output_w = stbr_info->output_w; + int kernel_texel_width = stbr__get_filter_texel_width_horizontal(stbr_info); + int channels = stbr_info->channels; + float* decode_buffer = stbr__get_decode_buffer(stbr_info); + stbr__contributors* horizontal_contributors = stbr_info->horizontal_contributors; + float* horizontal_coefficients = stbr_info->horizontal_coefficients; + + for (x = 0; x < output_w; x++) + { + int n0 = horizontal_contributors[x].n0; + int n1 = horizontal_contributors[x].n1; + + int out_texel_index = x * channels; + int coefficient_group_index = x * kernel_texel_width; + int coefficient_counter = 0; + + STBR_DEBUG_ASSERT(n1 >= n0); + STBR_DEBUG_ASSERT(n0 >= -stbr__get_filter_texel_margin_horizontal(stbr_info)); + STBR_DEBUG_ASSERT(n1 >= -stbr__get_filter_texel_margin_horizontal(stbr_info)); + STBR_DEBUG_ASSERT(n0 < stbr_info->input_w + stbr__get_filter_texel_margin_horizontal(stbr_info)); + STBR_DEBUG_ASSERT(n1 < stbr_info->input_w + stbr__get_filter_texel_margin_horizontal(stbr_info)); + + for (k = n0; k <= n1; k++) + { + int coefficient_index = coefficient_group_index + (coefficient_counter++); + int in_texel_index = k * channels; + float coefficient = horizontal_coefficients[coefficient_index]; + + int c; + for (c = 0; c < channels; c++) + output_buffer[out_texel_index + c] += decode_buffer[in_texel_index + c] * coefficient; + } + } +} + +static void stbr__resample_horizontal_downsample(stbr__info* stbr_info, int n, float* output_buffer) +{ + int x, k; + int input_w = stbr_info->input_w; + int output_w = stbr_info->output_w; + int kernel_texel_width = stbr__get_filter_texel_width_horizontal(stbr_info); + int channels = stbr_info->channels; + float* decode_buffer = stbr__get_decode_buffer(stbr_info); + stbr__contributors* horizontal_contributors = stbr_info->horizontal_contributors; + float* horizontal_coefficients = stbr_info->horizontal_coefficients; + int filter_texel_margin = stbr__get_filter_texel_margin_horizontal(stbr_info); + int max_x = input_w + filter_texel_margin * 2; + + STBR_DEBUG_ASSERT(!stbr__use_width_upsampling(stbr_info)); + + for (x = 0; x < max_x; x++) + { + int n0 = horizontal_contributors[x].n0; + int n1 = horizontal_contributors[x].n1; + + int in_x = x - filter_texel_margin; + int in_texel_index = in_x * channels; + int max_n = stbr__min(n1, output_w-1); + int coefficient_group = x*kernel_texel_width; + + STBR_DEBUG_ASSERT(n1 >= n0); + + // Using min and max to avoid writing into invalid texels. + for (k = stbr__max(n0, 0); k <= max_n; k++) + { + int coefficient_index = (k - n0) + coefficient_group; + int out_texel_index = k * channels; + float coefficient = horizontal_coefficients[coefficient_index]; + + int c; + for (c = 0; c < channels; c++) + output_buffer[out_texel_index + c] += decode_buffer[in_texel_index + c] * coefficient; + } + } +} + +static void stbr__decode_and_resample_upsample(stbr__info* stbr_info, int n) +{ + // Decode the nth scanline from the source image into the decode buffer. + stbr__decode_scanline(stbr_info, n); + + // Now resample it into the ring buffer. + if (stbr__use_width_upsampling(stbr_info)) + stbr__resample_horizontal_upsample(stbr_info, n, stbr__add_empty_ring_buffer_entry(stbr_info, n)); + else + stbr__resample_horizontal_downsample(stbr_info, n, stbr__add_empty_ring_buffer_entry(stbr_info, n)); + + // Now it's sitting in the ring buffer ready to be used as source for the vertical sampling. +} + +static void stbr__decode_and_resample_downsample(stbr__info* stbr_info, int n) +{ + // Decode the nth scanline from the source image into the decode buffer. + stbr__decode_scanline(stbr_info, n); + + memset(stbr_info->horizontal_buffer, 0, stbr_info->output_w * stbr_info->channels * sizeof(float)); + + // Now resample it into the horizontal buffer. + if (stbr__use_width_upsampling(stbr_info)) + stbr__resample_horizontal_upsample(stbr_info, n, stbr_info->horizontal_buffer); + else + stbr__resample_horizontal_downsample(stbr_info, n, stbr_info->horizontal_buffer); + + // Now it's sitting in the horizontal buffer ready to be distributed into the ring buffers. +} + +// Get the specified scan line from the ring buffer. +static float* stbr__get_ring_buffer_scanline(int get_scanline, float* ring_buffer, int begin_index, int first_scanline, int ring_buffer_size, int ring_buffer_length) +{ + int ring_buffer_index = (begin_index + (get_scanline - first_scanline)) % ring_buffer_size; + return stbr__get_ring_buffer_entry(ring_buffer, ring_buffer_index, ring_buffer_length); +} + + +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) + 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++) + { + 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++) + { + 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++) + { + 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++) + { + 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++) + { + 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++) + { + 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 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 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; + } +} + +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) +{ + int x, k; + int output_w = stbr_info->output_w; + stbr__contributors* vertical_contributors = &stbr_info->vertical_contributors; + float* vertical_coefficients = stbr_info->vertical_coefficients; + int channels = stbr_info->channels; + int premul_alpha_channel = stbr_info->premul_alpha_channel; + int type = stbr_info->type; + int colorspace = stbr_info->colorspace; + int kernel_texel_width = stbr__get_filter_texel_width_vertical(stbr_info); + void* output_data = stbr_info->output_data; + float* encode_buffer = stbr_info->encode_buffer; + int decode = STBR__DECODE(type, colorspace); + + float* ring_buffer = stbr_info->ring_buffer; + int ring_buffer_begin_index = stbr_info->ring_buffer_begin_index; + int ring_buffer_first_scanline = stbr_info->ring_buffer_first_scanline; + int ring_buffer_last_scanline = stbr_info->ring_buffer_last_scanline; + int ring_buffer_length = stbr_info->ring_buffer_length_bytes/sizeof(float); + + stbr__calculate_coefficients_upsample(stbr_info, in_first_scanline, in_last_scanline, in_center_of_out, vertical_contributors, vertical_coefficients); + + int n0 = vertical_contributors->n0; + int n1 = vertical_contributors->n1; + + int output_row_index = n * stbr_info->output_stride_bytes / stbr__type_size[type]; + + STBR_DEBUG_ASSERT(stbr__use_height_upsampling(stbr_info)); + STBR_DEBUG_ASSERT(n0 >= in_first_scanline); + STBR_DEBUG_ASSERT(n1 <= in_last_scanline); + + for (x = 0; x < output_w; x++) + { + int in_texel_index = x * channels; + int out_texel_index = output_row_index + x * channels; + int coefficient_counter = 0; + + STBR_DEBUG_ASSERT(n1 >= n0); + + memset(encode_buffer, 0, sizeof(float) * channels); + + for (k = n0; k <= n1; k++) + { + int coefficient_index = coefficient_counter++; + float* ring_buffer_entry = stbr__get_ring_buffer_scanline(k, ring_buffer, ring_buffer_begin_index, ring_buffer_first_scanline, kernel_texel_width, ring_buffer_length); + float coefficient = vertical_coefficients[coefficient_index]; + + int c; + for (c = 0; c < channels; c++) + encode_buffer[c] += ring_buffer_entry[in_texel_index + c] * coefficient; + } + + stbr__encode_scanline(output_data, out_texel_index, encode_buffer, 0, channels, premul_alpha_channel, decode); + } +} + +static void stbr__resample_vertical_downsample(stbr__info* stbr_info, int n, int in_first_scanline, int in_last_scanline, float in_center_of_out) +{ + int x, k; + int output_w = stbr_info->output_w; + int output_h = stbr_info->output_h; + stbr__contributors* vertical_contributors = &stbr_info->vertical_contributors; + float* vertical_coefficients = stbr_info->vertical_coefficients; + int channels = stbr_info->channels; + int kernel_texel_width = stbr__get_filter_texel_width_vertical(stbr_info); + void* output_data = stbr_info->output_data; + float* horizontal_buffer = stbr_info->horizontal_buffer; + + float* ring_buffer = stbr_info->ring_buffer; + int ring_buffer_begin_index = stbr_info->ring_buffer_begin_index; + int ring_buffer_first_scanline = stbr_info->ring_buffer_first_scanline; + int ring_buffer_last_scanline = stbr_info->ring_buffer_last_scanline; + int ring_buffer_length = stbr_info->ring_buffer_length_bytes/sizeof(float); + + stbr__calculate_coefficients_downsample(stbr_info, stbr_info->vertical_scale, in_first_scanline, in_last_scanline, in_center_of_out, vertical_contributors, vertical_coefficients); + + int n0 = vertical_contributors->n0; + int n1 = vertical_contributors->n1; + int max_n = stbr__min(n1, output_h - 1); + + STBR_DEBUG_ASSERT(!stbr__use_height_upsampling(stbr_info)); + STBR_DEBUG_ASSERT(n0 >= in_first_scanline); + STBR_DEBUG_ASSERT(n1 <= in_last_scanline); + STBR_DEBUG_ASSERT(n1 >= n0); + + // Using min and max to avoid writing into ring buffers that will be thrown out. + for (k = stbr__max(n0, 0); k <= max_n; k++) + { + int coefficient_index = k - n0; + + float* ring_buffer_entry = stbr__get_ring_buffer_scanline(k, ring_buffer, ring_buffer_begin_index, ring_buffer_first_scanline, kernel_texel_width, ring_buffer_length); + float coefficient = vertical_coefficients[coefficient_index]; + + for (x = 0; x < output_w; x++) + { + int in_texel_index = x * channels; + + int c; + for (c = 0; c < channels; c++) + ring_buffer_entry[in_texel_index + c] += horizontal_buffer[in_texel_index + c] * coefficient; + } + } +} + +static void stbr__buffer_loop_upsample(stbr__info* stbr_info) +{ + int y; + float scale_ratio = stbr_info->vertical_scale; + float out_scanlines_radius = stbr__filter_info_table[stbr_info->filter].support * scale_ratio; + + STBR_DEBUG_ASSERT(stbr__use_height_upsampling(stbr_info)); + + for (y = 0; y < stbr_info->output_h; y++) + { + float in_center_of_out = 0; // Center of the current out scanline in the in scanline space + int in_first_scanline = 0, in_last_scanline = 0; + + stbr__calculate_sample_range_upsample(y, out_scanlines_radius, scale_ratio, stbr_info->vertical_shift, &in_first_scanline, &in_last_scanline, &in_center_of_out); + + STBR_DEBUG_ASSERT(in_last_scanline - in_first_scanline <= stbr__get_filter_texel_width_vertical(stbr_info)); + + if (stbr_info->ring_buffer_begin_index >= 0) + { + // Get rid of whatever we don't need anymore. + while (in_first_scanline > stbr_info->ring_buffer_first_scanline) + { + if (stbr_info->ring_buffer_first_scanline == stbr_info->ring_buffer_last_scanline) + { + // We just popped the last scanline off the ring buffer. + // Reset it to the empty state. + stbr_info->ring_buffer_begin_index = -1; + stbr_info->ring_buffer_first_scanline = 0; + stbr_info->ring_buffer_last_scanline = 0; + break; + } + else + { + stbr_info->ring_buffer_first_scanline++; + stbr_info->ring_buffer_begin_index = (stbr_info->ring_buffer_begin_index + 1) % stbr__get_filter_texel_width_horizontal(stbr_info); + } + } + } + + // Load in new ones. + if (stbr_info->ring_buffer_begin_index < 0) + stbr__decode_and_resample_upsample(stbr_info, in_first_scanline); + + while (in_last_scanline > stbr_info->ring_buffer_last_scanline) + stbr__decode_and_resample_upsample(stbr_info, stbr_info->ring_buffer_last_scanline + 1); + + // Now all buffers should be ready to write a row of vertical sampling. + stbr__resample_vertical_upsample(stbr_info, y, in_first_scanline, in_last_scanline, in_center_of_out); + } +} + +static void stbr__empty_ring_buffer(stbr__info* stbr_info, int first_necessary_scanline) +{ + int output_stride = stbr_info->output_stride_bytes / stbr__type_size[stbr_info->type]; + int channels = stbr_info->channels; + int premul_alpha_channel = stbr_info->premul_alpha_channel; + int type = stbr_info->type; + int colorspace = stbr_info->colorspace; + int output_w = stbr_info->output_w; + void* output_data = stbr_info->output_data; + int decode = STBR__DECODE(type, colorspace); + + float* ring_buffer = stbr_info->ring_buffer; + int ring_buffer_length = stbr_info->ring_buffer_length_bytes/sizeof(float); + + if (stbr_info->ring_buffer_begin_index >= 0) + { + // Get rid of whatever we don't need anymore. + while (first_necessary_scanline > stbr_info->ring_buffer_first_scanline) + { + if (stbr_info->ring_buffer_first_scanline >= 0 && stbr_info->ring_buffer_first_scanline < stbr_info->output_h) + { + int x; + int output_row = stbr_info->ring_buffer_first_scanline * output_stride; + float* ring_buffer_entry = stbr__get_ring_buffer_entry(ring_buffer, stbr_info->ring_buffer_begin_index, ring_buffer_length); + + for (x = 0; x < output_w; x++) + { + int texel_index = x * channels; + int ring_texel_index = texel_index; + int output_texel_index = output_row + texel_index; + + stbr__encode_scanline(output_data, output_texel_index, ring_buffer_entry, ring_texel_index, channels, premul_alpha_channel, decode); + } + } + + if (stbr_info->ring_buffer_first_scanline == stbr_info->ring_buffer_last_scanline) + { + // We just popped the last scanline off the ring buffer. + // Reset it to the empty state. + stbr_info->ring_buffer_begin_index = -1; + stbr_info->ring_buffer_first_scanline = 0; + stbr_info->ring_buffer_last_scanline = 0; + break; + } + else + { + stbr_info->ring_buffer_first_scanline++; + stbr_info->ring_buffer_begin_index = (stbr_info->ring_buffer_begin_index + 1) % stbr__get_filter_texel_width_vertical(stbr_info); + } + } + } +} + +static void stbr__buffer_loop_downsample(stbr__info* stbr_info) +{ + int y; + float scale_ratio = stbr_info->vertical_scale; + int output_h = stbr_info->output_h; + float in_pixels_radius = stbr__filter_info_table[stbr_info->filter].support / scale_ratio; + int max_y = stbr_info->input_h + stbr__get_filter_texel_margin_vertical(stbr_info); + + STBR_DEBUG_ASSERT(!stbr__use_height_upsampling(stbr_info)); + + for (y = -stbr__get_filter_texel_margin_vertical(stbr_info); y < max_y; y++) + { + float out_center_of_in; // Center of the current out scanline in the in scanline space + int out_first_scanline, out_last_scanline; + + stbr__calculate_sample_range_downsample(y, in_pixels_radius, scale_ratio, stbr_info->vertical_shift, &out_first_scanline, &out_last_scanline, &out_center_of_in); + + STBR_DEBUG_ASSERT(out_last_scanline - out_first_scanline <= stbr__get_filter_texel_width_vertical(stbr_info)); + + if (out_last_scanline < 0 || out_first_scanline >= output_h) + continue; + + stbr__empty_ring_buffer(stbr_info, out_first_scanline); + + stbr__decode_and_resample_downsample(stbr_info, y); + + // Load in new ones. + if (stbr_info->ring_buffer_begin_index < 0) + stbr__add_empty_ring_buffer_entry(stbr_info, out_first_scanline); + + while (out_last_scanline > stbr_info->ring_buffer_last_scanline) + stbr__add_empty_ring_buffer_entry(stbr_info, stbr_info->ring_buffer_last_scanline + 1); + + // Now the horizontal buffer is ready to write to all ring buffer rows. + stbr__resample_vertical_downsample(stbr_info, y, out_first_scanline, out_last_scanline, out_center_of_in); + } + + stbr__empty_ring_buffer(stbr_info, stbr_info->output_h); +} + +STBRDEF int stbr_resize_advanced(const void* input_data, int input_w, int input_h, int input_stride_in_bytes, + void* output_data, int output_w, int output_h, int output_stride_in_bytes, + float s0, float t0, float s1, float t1, + int channels, int premul_alpha_channel, stbr_type type, stbr_filter filter, stbr_edge edge, stbr_colorspace colorspace, + void* tempmem, stbr_size_t tempmem_size_in_bytes) +{ + stbr_size_t memory_required = stbr_calculate_memory(input_w, input_h, output_w, output_h, s0, t0, s1, t1, channels, filter); + + int width_stride_input = input_stride_in_bytes ? input_stride_in_bytes : channels * input_w * stbr__type_size[type]; + int width_stride_output = output_stride_in_bytes ? output_stride_in_bytes : channels * output_w * stbr__type_size[type]; + +#ifdef STBR_DEBUG_OVERWRITE_TEST +#define OVERWRITE_ARRAY_SIZE 8 + unsigned char overwrite_output_before_pre[OVERWRITE_ARRAY_SIZE]; + unsigned char overwrite_tempmem_before_pre[OVERWRITE_ARRAY_SIZE]; + unsigned char overwrite_output_after_pre[OVERWRITE_ARRAY_SIZE]; + unsigned char overwrite_tempmem_after_pre[OVERWRITE_ARRAY_SIZE]; + + stbr_size_t begin_forbidden = width_stride_output * (output_h - 1) + output_w * channels * stbr__type_size[type]; + memcpy(overwrite_output_before_pre, &((unsigned char*)output_data)[-OVERWRITE_ARRAY_SIZE], OVERWRITE_ARRAY_SIZE); + memcpy(overwrite_output_after_pre, &((unsigned char*)output_data)[begin_forbidden], OVERWRITE_ARRAY_SIZE); + memcpy(overwrite_tempmem_before_pre, &((unsigned char*)tempmem)[-OVERWRITE_ARRAY_SIZE], OVERWRITE_ARRAY_SIZE); + memcpy(overwrite_tempmem_after_pre, &((unsigned char*)tempmem)[tempmem_size_in_bytes], OVERWRITE_ARRAY_SIZE); +#endif + + STBR_ASSERT(filter != 0); + STBR_ASSERT(filter < STBR_ARRAY_SIZE(stbr__filter_info_table)); + + if (!filter || filter >= STBR_ARRAY_SIZE(stbr__filter_info_table)) + return 0; + + STBR_ASSERT(s1 > s0); + STBR_ASSERT(t1 > t0); + + if (s1 <= s0 || t1 <= t0) + return 0; + + STBR_ASSERT(s1 <= 1 && s0 >= 0 && t1 <= 1 && t0 >= 0); + + if (s1 > 1 || s0 < 0 || t1 > 1 || t0 < 0) + return 0; + + STBR_ASSERT(premul_alpha_channel >= 0 && premul_alpha_channel < channels); + + if (premul_alpha_channel < 0 || premul_alpha_channel >= channels) + return 0; + + STBR_ASSERT(tempmem); + + if (!tempmem) + return 0; + + STBR_ASSERT(tempmem_size_in_bytes >= memory_required); + + if (tempmem_size_in_bytes < memory_required) + return 0; + + memset(tempmem, 0, tempmem_size_in_bytes); + + stbr__info* stbr_info = (stbr__info*)tempmem; + + stbr_info->input_data = input_data; + stbr_info->input_w = input_w; + stbr_info->input_h = input_h; + stbr_info->input_stride_bytes = width_stride_input; + + stbr_info->output_data = output_data; + stbr_info->output_w = output_w; + stbr_info->output_h = output_h; + stbr_info->output_stride_bytes = width_stride_output; + + stbr_info->s0 = s0; + stbr_info->t0 = t0; + stbr_info->s1 = s1; + stbr_info->t1 = t1; + + stbr_info->horizontal_scale = ((float)output_w / input_w) / (s1 - s0); + stbr_info->vertical_scale = ((float)output_h / input_h) / (t1 - t0); + + stbr_info->horizontal_shift = s0 * input_w / (s1 - s0); + stbr_info->vertical_shift = t0 * input_h / (t1 - t0); + + stbr_info->channels = channels; + stbr_info->premul_alpha_channel = premul_alpha_channel; + stbr_info->type = type; + stbr_info->filter = filter; + stbr_info->edge = edge; + stbr_info->colorspace = colorspace; + + stbr_info->ring_buffer_length_bytes = output_w * channels * sizeof(float); + stbr_info->decode_buffer_texels = input_w + stbr__get_filter_texel_margin_horizontal(stbr_info) * 2; + +#define STBR__NEXT_MEMPTR(current, old, newtype) (newtype*)(((unsigned char*)current) + old) + + stbr_info->horizontal_contributors = STBR__NEXT_MEMPTR(stbr_info, sizeof(stbr__info), stbr__contributors); + stbr_info->horizontal_coefficients = STBR__NEXT_MEMPTR(stbr_info->horizontal_contributors, stbr__get_horizontal_contributors(stbr_info) * sizeof(stbr__contributors), float); + stbr_info->vertical_coefficients = STBR__NEXT_MEMPTR(stbr_info->horizontal_coefficients, stbr__get_total_coefficients(stbr_info) * sizeof(float), float); + stbr_info->decode_buffer = STBR__NEXT_MEMPTR(stbr_info->vertical_coefficients, stbr__get_filter_texel_width_vertical(stbr_info) * sizeof(float), float); + + if (stbr__use_height_upsampling(stbr_info)) + { + stbr_info->horizontal_buffer = NULL; + stbr_info->ring_buffer = STBR__NEXT_MEMPTR(stbr_info->decode_buffer, stbr_info->decode_buffer_texels * channels * sizeof(float), float); + stbr_info->encode_buffer = STBR__NEXT_MEMPTR(stbr_info->ring_buffer, stbr_info->ring_buffer_length_bytes * stbr__get_filter_texel_width_horizontal(stbr_info), float); + + STBR_DEBUG_ASSERT((size_t)STBR__NEXT_MEMPTR(stbr_info->encode_buffer, stbr_info->channels * sizeof(float), unsigned char) == (size_t)tempmem + tempmem_size_in_bytes); + } + else + { + stbr_info->horizontal_buffer = STBR__NEXT_MEMPTR(stbr_info->decode_buffer, stbr_info->decode_buffer_texels * channels * sizeof(float), float); + stbr_info->ring_buffer = STBR__NEXT_MEMPTR(stbr_info->horizontal_buffer, output_w * channels * sizeof(float), float); + stbr_info->encode_buffer = NULL; + + STBR_DEBUG_ASSERT((size_t)STBR__NEXT_MEMPTR(stbr_info->ring_buffer, stbr_info->ring_buffer_length_bytes * stbr__get_filter_texel_width_vertical(stbr_info), unsigned char) == (size_t)tempmem + tempmem_size_in_bytes); + } + +#undef STBR__NEXT_MEMPTR + + // This signals that the ring buffer is empty + stbr_info->ring_buffer_begin_index = -1; + + stbr__calculate_horizontal_filters(stbr_info); + + if (stbr__use_height_upsampling(stbr_info)) + stbr__buffer_loop_upsample(stbr_info); + else + stbr__buffer_loop_downsample(stbr_info); + +#ifdef STBR_DEBUG_OVERWRITE_TEST + STBR_DEBUG_ASSERT(memcmp(overwrite_output_before_pre, &((unsigned char*)output_data)[-OVERWRITE_ARRAY_SIZE], OVERWRITE_ARRAY_SIZE) == 0); + STBR_DEBUG_ASSERT(memcmp(overwrite_output_after_pre, &((unsigned char*)output_data)[begin_forbidden], OVERWRITE_ARRAY_SIZE) == 0); + STBR_DEBUG_ASSERT(memcmp(overwrite_tempmem_before_pre, &((unsigned char*)tempmem)[-OVERWRITE_ARRAY_SIZE], OVERWRITE_ARRAY_SIZE) == 0); + STBR_DEBUG_ASSERT(memcmp(overwrite_tempmem_after_pre, &((unsigned char*)tempmem)[tempmem_size_in_bytes], OVERWRITE_ARRAY_SIZE) == 0); +#endif + + return 1; +} + + +STBRDEF stbr_size_t stbr_calculate_memory(int input_w, int input_h, int output_w, int output_h, float s0, float t0, float s1, float t1, int channels, stbr_filter filter) +{ + STBR_ASSERT(filter != 0); + STBR_ASSERT(filter < STBR_ARRAY_SIZE(stbr__filter_info_table)); + + float horizontal_scale = ((float)output_w / input_w) / (s1 - s0); + float vertical_scale = ((float)output_h / input_h) / (t1 - t0); + + int texel_margin = stbr__get_filter_texel_margin(filter, input_w, output_w, horizontal_scale); + int filter_height = stbr__get_filter_texel_width(filter, input_h, output_h, vertical_scale); + + int info_size = sizeof(stbr__info); + int contributors_size = stbr__get_horizontal_contributors_noinfo(filter, input_w, output_w, horizontal_scale) * sizeof(stbr__contributors); + int horizontal_coefficients_size = stbr__get_total_coefficients_noinfo(filter, input_w, output_w, horizontal_scale) * sizeof(float); + int vertical_coefficients_size = filter_height * sizeof(float); + int decode_buffer_size = (input_w + texel_margin*2) * channels * sizeof(float); + int horizontal_buffer_size = output_w * channels * sizeof(float); + int ring_buffer_size = output_w * channels * filter_height * sizeof(float); + int encode_buffer_size = channels * sizeof(float); + + if (stbr__use_upsampling(horizontal_scale)) + // The horizontal buffer is for when we're downsampling the height and we + // can't output the result of sampling the decode buffer directly into the + // ring buffers. + horizontal_buffer_size = 0; + else + // The encode buffer is to retain precision in the height upsampling method + // and isn't used when height downsampling. + encode_buffer_size = 0; + + return info_size + contributors_size + horizontal_coefficients_size + vertical_coefficients_size + decode_buffer_size + horizontal_buffer_size + ring_buffer_size + encode_buffer_size; +} + +STBRDEF stbr_inline int stbr_resize_uint8_srgb(const stbr_uint8* input_data, int input_w, int input_h, + stbr_uint8* output_data, int output_w, int output_h, + int channels, stbr_filter filter, stbr_edge edge) +{ + size_t memory_required = stbr_calculate_memory(input_w, input_h, output_w, output_h, 0, 0, 1, 1, channels, filter); + void* extra_memory = STBR_MALLOC(memory_required); + + if (!extra_memory) + return 0; + + int result = stbr_resize_advanced(input_data, input_w, input_h, 0, output_data, output_w, output_h, 0, 0, 0, 1, 1, channels, 0, STBR_TYPE_UINT8, filter, edge, STBR_COLORSPACE_SRGB, extra_memory, memory_required); + + STBR_FREE(extra_memory); + + return result; +} + +STBRDEF stbr_inline int stbr_resize_uint16_srgb(const stbr_uint16* input_data, int input_w, int input_h, + stbr_uint16* output_data, int output_w, int output_h, + int channels, stbr_filter filter, stbr_edge edge) +{ + size_t memory_required = stbr_calculate_memory(input_w, input_h, output_w, output_h, 0, 0, 1, 1, channels, filter); + void* extra_memory = STBR_MALLOC(memory_required); + + if (!extra_memory) + return 0; + + int result = stbr_resize_advanced(input_data, input_w, input_h, 0, output_data, output_w, output_h, 0, 0, 0, 1, 1, channels, 0, STBR_TYPE_UINT16, filter, edge, STBR_COLORSPACE_SRGB, extra_memory, memory_required); + + STBR_FREE(extra_memory); + + return result; +} + +STBRDEF stbr_inline int stbr_resize_uint32_srgb(const stbr_uint32* input_data, int input_w, int input_h, + stbr_uint32* output_data, int output_w, int output_h, + int channels, stbr_filter filter, stbr_edge edge) +{ + size_t memory_required = stbr_calculate_memory(input_w, input_h, output_w, output_h, 0, 0, 1, 1, channels, filter); + void* extra_memory = STBR_MALLOC(memory_required); + + if (!extra_memory) + return 0; + + int result = stbr_resize_advanced(input_data, input_w, input_h, 0, output_data, output_w, output_h, 0, 0, 0, 1, 1, channels, 0, STBR_TYPE_UINT32, filter, edge, STBR_COLORSPACE_SRGB, extra_memory, memory_required); + + STBR_FREE(extra_memory); + + return result; +} + +STBRDEF stbr_inline int stbr_resize_float_srgb(const float* input_data, int input_w, int input_h, + float* output_data, int output_w, int output_h, + int channels, stbr_filter filter, stbr_edge edge) +{ + size_t memory_required = stbr_calculate_memory(input_w, input_h, output_w, output_h, 0, 0, 1, 1, channels, filter); + void* extra_memory = STBR_MALLOC(memory_required); + + if (!extra_memory) + return 0; + + int result = stbr_resize_advanced(input_data, input_w, input_h, 0, output_data, output_w, output_h, 0, 0, 0, 1, 1, channels, 0, STBR_TYPE_FLOAT, filter, edge, STBR_COLORSPACE_SRGB, extra_memory, memory_required); + + STBR_FREE(extra_memory); + + return result; +} + +STBRDEF stbr_inline int stbr_resize_uint8_premultiply(const stbr_uint8* input_data, int input_w, int input_h, + stbr_uint8* output_data, int output_w, int output_h, + int channels, int premultiply_alpha_channel, stbr_filter filter, stbr_edge edge, stbr_colorspace colorspace) +{ + size_t memory_required = stbr_calculate_memory(input_w, input_h, output_w, output_h, 0, 0, 1, 1, channels, filter); + void* extra_memory = STBR_MALLOC(memory_required); + + if (!extra_memory) + return 0; + + int result = stbr_resize_advanced(input_data, input_w, input_h, 0, output_data, output_w, output_h, 0, 0, 0, 1, 1, channels, premultiply_alpha_channel, STBR_TYPE_UINT8, filter, edge, colorspace, extra_memory, memory_required); + + STBR_FREE(extra_memory); + + return result; +} + +STBRDEF stbr_inline int stbr_resize_uint16_premultiply(const stbr_uint16* input_data, int input_w, int input_h, + stbr_uint16* output_data, int output_w, int output_h, + int channels, int premultiply_alpha_channel, stbr_filter filter, stbr_edge edge, stbr_colorspace colorspace) +{ + size_t memory_required = stbr_calculate_memory(input_w, input_h, output_w, output_h, 0, 0, 1, 1, channels, filter); + void* extra_memory = STBR_MALLOC(memory_required); + + if (!extra_memory) + return 0; + + int result = stbr_resize_advanced(input_data, input_w, input_h, 0, output_data, output_w, output_h, 0, 0, 0, 1, 1, channels, premultiply_alpha_channel, STBR_TYPE_UINT16, filter, edge, colorspace, extra_memory, memory_required); + + STBR_FREE(extra_memory); + + return result; +} + +STBRDEF stbr_inline int stbr_resize_uint32_premultiply(const stbr_uint32* input_data, int input_w, int input_h, + stbr_uint32* output_data, int output_w, int output_h, + int channels, int premultiply_alpha_channel, stbr_filter filter, stbr_edge edge, stbr_colorspace colorspace) +{ + size_t memory_required = stbr_calculate_memory(input_w, input_h, output_w, output_h, 0, 0, 1, 1, channels, filter); + void* extra_memory = STBR_MALLOC(memory_required); + + if (!extra_memory) + return 0; + + int result = stbr_resize_advanced(input_data, input_w, input_h, 0, output_data, output_w, output_h, 0, 0, 0, 1, 1, channels, premultiply_alpha_channel, STBR_TYPE_UINT32, filter, edge, colorspace, extra_memory, memory_required); + + STBR_FREE(extra_memory); + + return result; +} + +STBRDEF stbr_inline int stbr_resize_float_premultiply(const float* input_data, int input_w, int input_h, + float* output_data, int output_w, int output_h, + int channels, int premultiply_alpha_channel, stbr_filter filter, stbr_edge edge, stbr_colorspace colorspace) +{ + size_t memory_required = stbr_calculate_memory(input_w, input_h, output_w, output_h, 0, 0, 1, 1, channels, filter); + void* extra_memory = STBR_MALLOC(memory_required); + + if (!extra_memory) + return 0; + + int result = stbr_resize_advanced(input_data, input_w, input_h, 0, output_data, output_w, output_h, 0, 0, 0, 1, 1, channels, premultiply_alpha_channel, STBR_TYPE_FLOAT, filter, edge, colorspace, extra_memory, memory_required); + + STBR_FREE(extra_memory); + + return result; +} + +STBRDEF stbr_inline int stbr_resize_uint8_subpixel(const stbr_uint8* input_data, int input_w, int input_h, + stbr_uint8* output_data, int output_w, int output_h, + float s0, float t0, float s1, float t1, + int channels, stbr_filter filter, stbr_edge edge) +{ + size_t memory_required = stbr_calculate_memory(input_w, input_h, output_w, output_h, s0, t0, s1, t1, channels, filter); + void* extra_memory = STBR_MALLOC(memory_required); + + if (!extra_memory) + return 0; + + int result = stbr_resize_advanced(input_data, input_w, input_h, 0, output_data, output_w, output_h, 0, s0, t0, s1, t1, channels, 0, STBR_TYPE_UINT8, filter, edge, STBR_COLORSPACE_SRGB, extra_memory, memory_required); + + STBR_FREE(extra_memory); + + return result; +} + +STBRDEF stbr_inline int stbr_resize_uint16_subpixel(const stbr_uint16* input_data, int input_w, int input_h, + stbr_uint16* output_data, int output_w, int output_h, + float s0, float t0, float s1, float t1, + int channels, stbr_filter filter, stbr_edge edge) +{ + size_t memory_required = stbr_calculate_memory(input_w, input_h, output_w, output_h, s0, t0, s1, t1, channels, filter); + void* extra_memory = STBR_MALLOC(memory_required); + + if (!extra_memory) + return 0; + + int result = stbr_resize_advanced(input_data, input_w, input_h, 0, output_data, output_w, output_h, 0, s0, t0, s1, t1, channels, 0, STBR_TYPE_UINT16, filter, edge, STBR_COLORSPACE_SRGB, extra_memory, memory_required); + + STBR_FREE(extra_memory); + + return result; +} + +STBRDEF stbr_inline int stbr_resize_uint32_subpixel(const stbr_uint32* input_data, int input_w, int input_h, + stbr_uint32* output_data, int output_w, int output_h, + float s0, float t0, float s1, float t1, + int channels, stbr_filter filter, stbr_edge edge) +{ + size_t memory_required = stbr_calculate_memory(input_w, input_h, output_w, output_h, s0, t0, s1, t1, channels, filter); + void* extra_memory = STBR_MALLOC(memory_required); + + if (!extra_memory) + return 0; + + int result = stbr_resize_advanced(input_data, input_w, input_h, 0, output_data, output_w, output_h, 0, s0, t0, s1, t1, channels, 0, STBR_TYPE_UINT32, filter, edge, STBR_COLORSPACE_SRGB, extra_memory, memory_required); + + STBR_FREE(extra_memory); + + return result; +} + +STBRDEF stbr_inline int stbr_resize_float_subpixel(const float* input_data, int input_w, int input_h, + float* output_data, int output_w, int output_h, + float s0, float t0, float s1, float t1, + int channels, stbr_filter filter, stbr_edge edge) +{ + size_t memory_required = stbr_calculate_memory(input_w, input_h, output_w, output_h, s0, t0, s1, t1, channels, filter); + void* extra_memory = STBR_MALLOC(memory_required); + + if (!extra_memory) + return 0; + + int result = stbr_resize_advanced(input_data, input_w, input_h, 0, output_data, output_w, output_h, 0, s0, t0, s1, t1, channels, 0, STBR_TYPE_FLOAT, filter, edge, STBR_COLORSPACE_SRGB, extra_memory, memory_required); + + STBR_FREE(extra_memory); + + return result; +} + +STBRDEF int stbr_resize_arbitrary(const void* input_data, int input_w, int input_h, int input_stride_in_bytes, + void* output_data, int output_w, int output_h, int output_stride_in_bytes, + float s0, float t0, float s1, float t1, + int channels, int premultiply_alpha_channel, stbr_type type, stbr_filter filter, stbr_edge edge, stbr_colorspace colorspace) +{ + size_t memory_required = stbr_calculate_memory(input_w, input_h, output_w, output_h, s0, t0, s1, t1, channels, filter); + void* extra_memory = STBR_MALLOC(memory_required); + + if (!extra_memory) + return 0; + + int result = stbr_resize_advanced(input_data, input_w, input_h, input_stride_in_bytes, output_data, output_w, output_h, output_stride_in_bytes, s0, t0, s1, t1, channels, premultiply_alpha_channel, type, filter, edge, colorspace, extra_memory, memory_required); + + STBR_FREE(extra_memory); + + return result; +} + +#endif // STB_RESAMPLE_IMPLEMENTATION + +/* +revision history: + 0.50 (2014-07-29) + first released version +*/ diff --git a/tests/resample_test.cpp b/tests/resample_test.cpp new file mode 100644 index 0000000..98e7166 --- /dev/null +++ b/tests/resample_test.cpp @@ -0,0 +1,430 @@ +#ifdef _WIN32 +#define STBR_ASSERT(x) \ + if (!(x)) \ + __debugbreak(); +#else +#include +#define STBR_ASSERT(x) assert(x) +#endif + +#define STB_RESAMPLE_IMPLEMENTATION +#define STB_RESAMPLE_STATIC +#include "stb_resample.h" + +#define STB_IMAGE_WRITE_IMPLEMENTATION +#include "stb_image_write.h" + +#define STB_IMAGE_IMPLEMENTATION +#include "stb_image.h" + +#ifdef _WIN32 +#include +#endif + +void test_suite(); + +int main(int argc, char** argv) +{ + unsigned char* input_data; + unsigned char* output_data; + int w, h; + int n; + int out_w, out_h, out_stride; + +#if 1 + test_suite(); + return 0; +#endif + + if (argc <= 1) + { + printf("No input image\n"); + return 1; + } + + input_data = stbi_load(argv[1], &w, &h, &n, 0); + if (!input_data) + { + printf("Input image could not be loaded"); + return 1; + } + + out_w = 512; + out_h = 512; + out_stride = (out_w + 10) * n; + + output_data = (unsigned char*)malloc(out_stride * out_h); + + int in_w = 512; + int in_h = 512; + + float s0 = 0.25f; + float t0 = 0.25f; + float s1 = 0.75f; + float t1 = 0.75f; + + size_t memory_required = stbr_calculate_memory(in_w, in_h, out_w, out_h, s0, t0, s1, t1, n, STBR_FILTER_CATMULLROM); + void* extra_memory = malloc(memory_required); + + // Cut out the outside 64 pixels all around to test the stride. + int border = 64; + STBR_ASSERT(in_w + border <= w); + STBR_ASSERT(in_h + border <= h); + +#ifdef PERF_TEST + struct timeb initial_time_millis, final_time_millis; + + long average = 0; + for (int j = 0; j < 10; j++) + { + ftime(&initial_time_millis); + for (int i = 0; i < 100; i++) + stbr_resize_advanced(input_data + w * border * n + border * n, in_w, in_h, w*n, output_data, out_w, out_h, out_stride, n, STBR_TYPE_UINT8, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, extra_memory, memory_required); + ftime(&final_time_millis); + long lapsed_ms = (long)(final_time_millis.time - initial_time_millis.time) * 1000 + (final_time_millis.millitm - initial_time_millis.millitm); + printf("Resample: %dms\n", lapsed_ms); + + average += lapsed_ms; + } + + average /= 10; + + printf("Average: %dms\n", average); +#else + stbr_resize_advanced(input_data + w * border * n + border * n, in_w, in_h, w*n, output_data, out_w, out_h, out_stride, s0, t0, s1, t1, n, 0, STBR_TYPE_UINT8, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, extra_memory, memory_required); +#endif + + free(extra_memory); + stbi_image_free(input_data); + + stbi_write_png("output.png", out_w, out_h, n, output_data, out_stride); + + free(output_data); + + return 0; +} + +void resize_image(const char* filename, float width_percent, float height_percent, stbr_filter filter, stbr_edge edge, stbr_colorspace colorspace, const char* output_filename) +{ + int w, h, n; + + unsigned char* input_data = stbi_load(filename, &w, &h, &n, 0); + if (!input_data) + { + printf("Input image could not be loaded"); + return; + } + + int out_w = (int)(w * width_percent); + int out_h = (int)(h * height_percent); + + unsigned char* output_data = (unsigned char*)malloc(out_w * out_h * n); + + size_t memory_required = stbr_calculate_memory(w, h, out_w, out_h, 0, 0, 1, 1, n, filter); + void* extra_memory = malloc(memory_required); + + stbr_resize_advanced(input_data, w, h, 0, output_data, out_w, out_h, 0, 0, 0, 1, 1, n, 0, STBR_TYPE_UINT8, filter, edge, colorspace, extra_memory, memory_required); + + free(extra_memory); + stbi_image_free(input_data); + + stbi_write_png(output_filename, out_w, out_h, n, output_data, 0); + + free(output_data); +} + +template +void convert_image(const F* input, T* output, int length) +{ + double f = (pow(2.0, 8.0 * sizeof(T)) - 1) / (pow(2.0, 8.0 * sizeof(F)) - 1); + for (int i = 0; i < length; i++) + output[i] = (T)(((double)input[i]) * f); +} + +template +void test_format(const char* file, float width_percent, float height_percent, stbr_type type, stbr_colorspace colorspace) +{ + int w, h, n; + unsigned char* input_data = stbi_load(file, &w, &h, &n, 0); + + int new_w = (int)(w * width_percent); + int new_h = (int)(h * height_percent); + + T* T_data = (T*)malloc(w * h * n * sizeof(T)); + convert_image(input_data, T_data, w * h * n); + + T* output_data = (T*)malloc(new_w * new_h * n * sizeof(T)); + + size_t required = stbr_calculate_memory(w, h, new_w, new_h, 0, 0, 1, 1, n, STBR_FILTER_CATMULLROM); + void* extra_memory = malloc(required); + stbr_resize_advanced(T_data, w, h, 0, output_data, new_w, new_h, 0, 0, 0, 1, 1, n, 0, type, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, colorspace, extra_memory, required); + free(extra_memory); + + free(T_data); + stbi_image_free(input_data); + + unsigned char* char_data = (unsigned char*)malloc(new_w * new_h * n * sizeof(char)); + convert_image(output_data, char_data, new_w * new_h * n); + + char output[200]; + sprintf(output, "test-output/type-%d-%d-%d-%d-%s", type, colorspace, new_w, new_h, file); + stbi_write_png(output, new_w, new_h, n, char_data, 0); + + free(char_data); + free(output_data); +} + +void convert_image_float(const unsigned char* input, float* output, int length) +{ + for (int i = 0; i < length; i++) + output[i] = ((float)input[i])/255; +} + +void convert_image_float(const float* input, unsigned char* output, int length) +{ + for (int i = 0; i < length; i++) + output[i] = (unsigned char)(input[i] * 255); +} + +void test_float(const char* file, float width_percent, float height_percent, stbr_type type, stbr_colorspace colorspace) +{ + int w, h, n; + unsigned char* input_data = stbi_load(file, &w, &h, &n, 0); + + int new_w = (int)(w * width_percent); + int new_h = (int)(h * height_percent); + + float* T_data = (float*)malloc(w * h * n * sizeof(float)); + convert_image_float(input_data, T_data, w * h * n); + + float* output_data = (float*)malloc(new_w * new_h * n * sizeof(float)); + + size_t required = stbr_calculate_memory(w, h, new_w, new_h, 0, 0, 1, 1, n, STBR_FILTER_CATMULLROM); + void* extra_memory = malloc(required); + stbr_resize_advanced(T_data, w, h, 0, output_data, new_w, new_h, 0, 0, 0, 1, 1, n, 0, type, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, colorspace, extra_memory, required); + free(extra_memory); + + free(T_data); + stbi_image_free(input_data); + + unsigned char* char_data = (unsigned char*)malloc(new_w * new_h * n * sizeof(char)); + convert_image_float(output_data, char_data, new_w * new_h * n); + + char output[200]; + sprintf(output, "test-output/type-%d-%d-%d-%d-%s", type, colorspace, new_w, new_h, file); + stbi_write_png(output, new_w, new_h, n, char_data, 0); + + free(char_data); + free(output_data); +} + +void test_channels(const char* file, float width_percent, float height_percent, int channels) +{ + int w, h, n; + unsigned char* input_data = stbi_load(file, &w, &h, &n, 0); + + int new_w = (int)(w * width_percent); + int new_h = (int)(h * height_percent); + + unsigned char* channels_data = (unsigned char*)malloc(w * h * channels * sizeof(unsigned char)); + + for (int i = 0; i < w * h; i++) + { + int input_position = i * n; + int output_position = i * channels; + + for (int c = 0; c < channels; c++) + channels_data[output_position + c] = input_data[input_position + stbr__min(c, n)]; + } + + unsigned char* output_data = (unsigned char*)malloc(new_w * new_h * channels * sizeof(unsigned char)); + + stbr_resize_uint8_srgb(channels_data, w, h, output_data, new_w, new_h, channels, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP); + + free(channels_data); + stbi_image_free(input_data); + + char output[200]; + sprintf(output, "test-output/channels-%d-%d-%d-%s", channels, new_w, new_h, file); + stbi_write_png(output, new_w, new_h, channels, output_data, 0); + + free(output_data); +} + +void test_subpixel(const char* file, float width_percent, float height_percent, float s1, float t1) +{ + int w, h, n; + unsigned char* input_data = stbi_load(file, &w, &h, &n, 0); + + s1 = ((float)w - 1 + s1)/w; + t1 = ((float)h - 1 + t1)/h; + + int new_w = (int)(w * width_percent); + int new_h = (int)(h * height_percent); + + unsigned char* output_data = (unsigned char*)malloc(new_w * new_h * n * sizeof(unsigned char)); + + size_t tempmem_size = stbr_calculate_memory(w, h, new_w, new_h, 0, 0, s1, t1, n, STBR_FILTER_CATMULLROM); + void* tempmem = malloc(tempmem_size); + + stbr_resize_advanced(input_data, w, h, 0, output_data, new_w, new_h, 0, 0, 0, s1, t1, n, 0, STBR_TYPE_UINT8, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, tempmem, tempmem_size); + + free(tempmem); + + stbi_image_free(input_data); + + char output[200]; + sprintf(output, "test-output/subpixel-%d-%d-%f-%f-%s", new_w, new_h, s1, t1, file); + stbi_write_png(output, new_w, new_h, n, output_data, 0); + + free(output_data); +} + +void test_premul(const char* file) +{ + int w, h, n; + unsigned char* input_data = stbi_load(file, &w, &h, &n, 4); + n = 4; + + // Set alpha for the top half. + for (int x = 0; x < w; x++) + { + for (int y = 0; y < h / 2; y++) + input_data[(y*w + x)*n + 3] = input_data[(y*w + x)*n + 0]; + } + + stbi_write_png("test-output/premul-original.png", w, h, n, input_data, 0); + + 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)); + + size_t tempmem_size = stbr_calculate_memory(w, h, new_w, new_h, 0, 0, 1, 1, n, STBR_FILTER_CATMULLROM); + void* tempmem = malloc(tempmem_size); + + stbr_resize_advanced(input_data, w, h, 0, output_data, new_w, new_h, 0, 0, 0, 1, 1, n, 3, STBR_TYPE_UINT8, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, tempmem, tempmem_size); + + char output[200]; + sprintf(output, "test-output/premul-%s", file); + stbi_write_png(output, new_w, new_h, n, output_data, 0); + + stbr_resize_advanced(input_data, w, h, 0, output_data, new_w, new_h, 0, 0, 0, 1, 1, n, 0, STBR_TYPE_UINT8, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, tempmem, tempmem_size); + + sprintf(output, "test-output/nopremul-%s", file); + stbi_write_png(output, new_w, new_h, n, output_data, 0); + + free(tempmem); + + stbi_image_free(input_data); + + free(output_data); +} + +void test_suite() +{ + test_premul("barbara.png"); + + for (int i = 0; i < 10; i++) + test_subpixel("barbara.png", 0.5f, 0.5f, (float)i / 10, 1); + + for (int i = 0; i < 10; i++) + test_subpixel("barbara.png", 0.5f, 0.5f, 1, (float)i / 10); + + for (int i = 0; i < 10; i++) + test_subpixel("barbara.png", 2, 2, (float)i / 10, 1); + + for (int i = 0; i < 10; i++) + test_subpixel("barbara.png", 2, 2, 1, (float)i / 10); + + // Channels test + test_channels("barbara.png", 0.5f, 0.5f, 1); + test_channels("barbara.png", 0.5f, 0.5f, 2); + test_channels("barbara.png", 0.5f, 0.5f, 3); + test_channels("barbara.png", 0.5f, 0.5f, 4); + + test_channels("barbara.png", 2, 2, 1); + test_channels("barbara.png", 2, 2, 2); + test_channels("barbara.png", 2, 2, 3); + test_channels("barbara.png", 2, 2, 4); + + // Edge behavior tests + resize_image("hgradient.png", 2, 2, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_LINEAR, "test-output/hgradient-clamp.png"); + resize_image("hgradient.png", 2, 2, STBR_FILTER_CATMULLROM, STBR_EDGE_WRAP, STBR_COLORSPACE_LINEAR, "test-output/hgradient-wrap.png"); + + resize_image("vgradient.png", 2, 2, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_LINEAR, "test-output/vgradient-clamp.png"); + resize_image("vgradient.png", 2, 2, STBR_FILTER_CATMULLROM, STBR_EDGE_WRAP, STBR_COLORSPACE_LINEAR, "test-output/vgradient-wrap.png"); + + resize_image("1px-border.png", 2, 2, STBR_FILTER_CATMULLROM, STBR_EDGE_REFLECT, STBR_COLORSPACE_LINEAR, "test-output/1px-border-reflect.png"); + resize_image("1px-border.png", 2, 2, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_LINEAR, "test-output/1px-border-clamp.png"); + + // sRGB tests + resize_image("gamma_colors.jpg", .5f, .5f, STBR_FILTER_CATMULLROM, STBR_EDGE_REFLECT, STBR_COLORSPACE_SRGB, "test-output/gamma_colors.jpg"); + resize_image("gamma_2.2.jpg", .5f, .5f, STBR_FILTER_CATMULLROM, STBR_EDGE_REFLECT, STBR_COLORSPACE_SRGB, "test-output/gamma_2.2.jpg"); + resize_image("gamma_dalai_lama_gray.jpg", .5f, .5f, STBR_FILTER_CATMULLROM, STBR_EDGE_REFLECT, STBR_COLORSPACE_SRGB, "test-output/gamma_dalai_lama_gray.jpg"); + + // filter tests + resize_image("barbara.png", 2, 2, STBR_FILTER_NEAREST, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, "test-output/barbara-upsample-nearest.png"); + resize_image("barbara.png", 2, 2, STBR_FILTER_BILINEAR, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, "test-output/barbara-upsample-bilinear.png"); + resize_image("barbara.png", 2, 2, STBR_FILTER_BICUBIC, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, "test-output/barbara-upsample-bicubic.png"); + resize_image("barbara.png", 2, 2, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, "test-output/barbara-upsample-catmullrom.png"); + resize_image("barbara.png", 2, 2, STBR_FILTER_MITCHELL, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, "test-output/barbara-upsample-mitchell.png"); + + resize_image("barbara.png", 0.5f, 0.5f, STBR_FILTER_NEAREST, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, "test-output/barbara-downsample-nearest.png"); + resize_image("barbara.png", 0.5f, 0.5f, STBR_FILTER_BILINEAR, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, "test-output/barbara-downsample-bilinear.png"); + resize_image("barbara.png", 0.5f, 0.5f, STBR_FILTER_BICUBIC, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, "test-output/barbara-downsample-bicubic.png"); + resize_image("barbara.png", 0.5f, 0.5f, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, "test-output/barbara-downsample-catmullrom.png"); + resize_image("barbara.png", 0.5f, 0.5f, STBR_FILTER_MITCHELL, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, "test-output/barbara-downsample-mitchell.png"); + + for (int i = 10; i < 100; i++) + { + char outname[200]; + sprintf(outname, "test-output/barbara-width-%d.jpg", i); + resize_image("barbara.png", (float)i / 100, 1, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, outname); + } + + for (int i = 110; i < 500; i += 10) + { + char outname[200]; + sprintf(outname, "test-output/barbara-width-%d.jpg", i); + resize_image("barbara.png", (float)i / 100, 1, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, outname); + } + + for (int i = 10; i < 100; i++) + { + char outname[200]; + sprintf(outname, "test-output/barbara-height-%d.jpg", i); + resize_image("barbara.png", 1, (float)i / 100, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, outname); + } + + for (int i = 110; i < 500; i += 10) + { + char outname[200]; + sprintf(outname, "test-output/barbara-height-%d.jpg", i); + resize_image("barbara.png", 1, (float)i / 100, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, outname); + } + + for (int i = 50; i < 200; i += 10) + { + char outname[200]; + sprintf(outname, "test-output/barbara-width-height-%d.jpg", i); + resize_image("barbara.png", 100 / (float)i, (float)i / 100, STBR_FILTER_CATMULLROM, STBR_EDGE_CLAMP, STBR_COLORSPACE_SRGB, outname); + } + + test_format("barbara.png", 0.5, 2.0, STBR_TYPE_UINT16, STBR_COLORSPACE_SRGB); + test_format("barbara.png", 0.5, 2.0, STBR_TYPE_UINT16, STBR_COLORSPACE_LINEAR); + test_format("barbara.png", 2.0, 0.5, STBR_TYPE_UINT16, STBR_COLORSPACE_SRGB); + test_format("barbara.png", 2.0, 0.5, STBR_TYPE_UINT16, STBR_COLORSPACE_LINEAR); + + test_format("barbara.png", 0.5, 2.0, STBR_TYPE_UINT32, STBR_COLORSPACE_SRGB); + test_format("barbara.png", 0.5, 2.0, STBR_TYPE_UINT32, STBR_COLORSPACE_LINEAR); + test_format("barbara.png", 2.0, 0.5, STBR_TYPE_UINT32, STBR_COLORSPACE_SRGB); + test_format("barbara.png", 2.0, 0.5, STBR_TYPE_UINT32, STBR_COLORSPACE_LINEAR); + + test_float("barbara.png", 0.5, 2.0, STBR_TYPE_FLOAT, STBR_COLORSPACE_SRGB); + test_float("barbara.png", 0.5, 2.0, STBR_TYPE_FLOAT, STBR_COLORSPACE_LINEAR); + test_float("barbara.png", 2.0, 0.5, STBR_TYPE_FLOAT, STBR_COLORSPACE_SRGB); + test_float("barbara.png", 2.0, 0.5, STBR_TYPE_FLOAT, STBR_COLORSPACE_LINEAR); +} + + diff --git a/tests/resample_test_c.c b/tests/resample_test_c.c new file mode 100644 index 0000000..dcc3572 --- /dev/null +++ b/tests/resample_test_c.c @@ -0,0 +1,11 @@ +#ifdef _WIN32 +#define STBR_ASSERT(x) \ + if (!(x)) \ + __debugbreak(); +#endif + +#define STB_RESAMPLE_IMPLEMENTATION +#define STB_RESAMPLE_STATIC +#include "stb_resample.h" + +// Just to make sure it will build properly with a c compiler