diff options
Diffstat (limited to 'converter/other/qoi.h')
-rw-r--r-- | converter/other/qoi.h | 471 |
1 files changed, 40 insertions, 431 deletions
diff --git a/converter/other/qoi.h b/converter/other/qoi.h index 2b782860..3eb3d3e8 100644 --- a/converter/other/qoi.h +++ b/converter/other/qoi.h @@ -1,3 +1,5 @@ +#ifndef QOI_H_INCLUDED +#define QOI_H_INCLUDED /* QOI - The "Quite OK Image" format for fast, lossless image compression @@ -35,12 +37,6 @@ stb_image_write QOI offers 20x-50x faster encoding, 3x-4x faster decoding and -- Synopsis -// Define `QOI_IMPLEMENTATION` in *one* C/C++ file before including this -// library to create the implementation. - -#define QOI_IMPLEMENTATION -#include "qoi.h" - // Encode and store an RGBA buffer to the file system. The qoi_desc describes // the input pixel data. qoi_write("image_new.qoi", rgba_pixels, &(qoi_desc){ @@ -68,9 +64,6 @@ This library provides the following functions; See the function declaration below for the signature and more information. -If you don't want/need the qoi_read and qoi_write functions, you can define -QOI_NO_STDIO before including this library. - This library uses malloc() and free(). To supply your own malloc implementation you can define QOI_MALLOC and QOI_FREE before including this library. @@ -228,442 +221,58 @@ The alpha value remains unchanged from the previous pixel. */ -/* ----------------------------------------------------------------------------- -Header - Public functions */ - -#ifndef QOI_H -#define QOI_H +/* A pointer to a qoi_desc struct has to be supplied to all of qoi's + functions. It describes either the input format (for qoi_write and + qoi_encode), or is filled with the description read from the file header + (for qoi_read and qoi_decode). -#ifdef __cplusplus -extern "C" { -#endif - -/* A pointer to a qoi_desc struct has to be supplied to all of qoi's functions. -It describes either the input format (for qoi_write and qoi_encode), or is -filled with the description read from the file header (for qoi_read and -qoi_decode). + The colorspace in this qoi_desc is an enum where + 0 = sRGB, i.e. gamma scaled RGB channels and a linear alpha channel + 1 = all channels are linear -The colorspace in this qoi_desc is an enum where - 0 = sRGB, i.e. gamma scaled RGB channels and a linear alpha channel - 1 = all channels are linear -You may use the constants QOI_SRGB or QOI_LINEAR. The colorspace is purely -informative. It will be saved to the file header, but does not affect -how chunks are en-/decoded. */ + You may use the constants QOI_SRGB or QOI_LINEAR. The colorspace is purely + informative. It will be saved to the file header, but does not affect how + chunks are en-/decoded. +*/ -#define QOI_SRGB 0 -#define QOI_LINEAR 1 +typedef enum { + QOI_SRGB = 0, + QOI_LINEAR = 1 +} qoi_Colorspace; typedef struct { - unsigned int width; - unsigned int height; - unsigned char channels; - unsigned char colorspace; -} qoi_desc; - -#ifndef QOI_NO_STDIO - -/* Encode raw RGB or RGBA pixels into a QOI image and write it to the file -system. The qoi_desc struct must be filled with the image width, height, -number of channels (3 = RGB, 4 = RGBA) and the colorspace. - -The function returns 0 on failure (invalid parameters, or fopen or malloc -failed) or the number of bytes written on success. */ - -int qoi_write(const char *filename, const void *data, const qoi_desc *desc); - - -/* Read and decode a QOI image from the file system. If channels is 0, the -number of channels from the file header is used. If channels is 3 or 4 the -output format will be forced into this number of channels. - -The function either returns NULL on failure (invalid data, or malloc or fopen -failed) or a pointer to the decoded pixels. On success, the qoi_desc struct -will be filled with the description from the file header. - -The returned pixel data should be free()d after use. */ - -void *qoi_read(const char *filename, qoi_desc *desc, int channels); - -#endif /* QOI_NO_STDIO */ - + unsigned int width; + unsigned int height; + unsigned int channelCt; + qoi_Colorspace colorspace; +} qoi_Desc; /* Encode raw RGB or RGBA pixels into a QOI image in memory. -The function either returns NULL on failure (invalid parameters or malloc -failed) or a pointer to the encoded data on success. On success the out_len -is set to the size in bytes of the encoded data. - -The returned qoi data should be free()d after use. */ + The function either returns NULL on failure (invalid parameters or malloc + failed) or a pointer to the encoded data on success. On success the out_len + is set to the size in bytes of the encoded data. -void *qoi_encode(const void *data, const qoi_desc *desc, int *out_len); + The returned qoi data should be free()d after use. +*/ +void * +qoi_encode(const void * const data, + const qoi_Desc * const descP, + unsigned int * const outLenP); /* Decode a QOI image from memory. -The function either returns NULL on failure (invalid parameters or malloc -failed) or a pointer to the decoded pixels. On success, the qoi_desc struct -is filled with the description from the file header. - -The returned pixel data should be free()d after use. */ - -void *qoi_decode(const void *data, int size, qoi_desc *desc, int channels); + The function either returns NULL on failure (invalid parameters or malloc + failed) or a pointer to the decoded pixels. On success, the qoi_Desc struct + is filled with the description from the file header. + The returned pixel data should be free()d after use. +*/ -#ifdef __cplusplus -} -#endif -#endif /* QOI_H */ - - -/* ----------------------------------------------------------------------------- -Implementation */ - -#ifdef QOI_IMPLEMENTATION -#include <stdlib.h> -#include <string.h> +void * +qoi_decode(const void * const data, + unsigned int const size, + qoi_Desc * const descP); -#ifndef QOI_MALLOC - #define QOI_MALLOC(sz) malloc(sz) - #define QOI_FREE(p) free(p) -#endif -#ifndef QOI_ZEROARR - #define QOI_ZEROARR(a) memset((a),0,sizeof(a)) #endif - -#define QOI_OP_INDEX 0x00 /* 00xxxxxx */ -#define QOI_OP_DIFF 0x40 /* 01xxxxxx */ -#define QOI_OP_LUMA 0x80 /* 10xxxxxx */ -#define QOI_OP_RUN 0xc0 /* 11xxxxxx */ -#define QOI_OP_RGB 0xfe /* 11111110 */ -#define QOI_OP_RGBA 0xff /* 11111111 */ - -#define QOI_MASK_2 0xc0 /* 11000000 */ - -#define QOI_COLOR_HASH(C) (C.rgba.r*3 + C.rgba.g*5 + C.rgba.b*7 + C.rgba.a*11) -#define QOI_MAGIC \ - (((unsigned int)'q') << 24 | ((unsigned int)'o') << 16 | \ - ((unsigned int)'i') << 8 | ((unsigned int)'f')) -#define QOI_HEADER_SIZE 14 - -/* 2GB is the max file size that this implementation can safely handle. We guard -against anything larger than that, assuming the worst case with 5 bytes per -pixel, rounded down to a nice clean value. 400 million pixels ought to be -enough for anybody. */ -#define QOI_PIXELS_MAX ((unsigned int)400000000) - -typedef union { - struct { unsigned char r, g, b, a; } rgba; - unsigned int v; -} qoi_rgba_t; - -static const unsigned char qoi_padding[8] = {0,0,0,0,0,0,0,1}; - -static void qoi_write_32(unsigned char *bytes, int *p, unsigned int v) { - bytes[(*p)++] = (0xff000000 & v) >> 24; - bytes[(*p)++] = (0x00ff0000 & v) >> 16; - bytes[(*p)++] = (0x0000ff00 & v) >> 8; - bytes[(*p)++] = (0x000000ff & v); -} - -static unsigned int qoi_read_32(const unsigned char *bytes, int *p) { - unsigned int a = bytes[(*p)++]; - unsigned int b = bytes[(*p)++]; - unsigned int c = bytes[(*p)++]; - unsigned int d = bytes[(*p)++]; - return a << 24 | b << 16 | c << 8 | d; -} - -void *qoi_encode(const void *data, const qoi_desc *desc, int *out_len) { - int i, max_size, p, run; - int px_len, px_end, px_pos, channels; - unsigned char *bytes; - const unsigned char *pixels; - qoi_rgba_t index[64]; - qoi_rgba_t px, px_prev; - - if ( - data == NULL || out_len == NULL || desc == NULL || - desc->width == 0 || desc->height == 0 || - desc->channels < 3 || desc->channels > 4 || - desc->colorspace > 1 || - desc->height >= QOI_PIXELS_MAX / desc->width - ) { - return NULL; - } - - max_size = - desc->width * desc->height * (desc->channels + 1) + - QOI_HEADER_SIZE + sizeof(qoi_padding); - - p = 0; - bytes = (unsigned char *) QOI_MALLOC(max_size); - if (!bytes) { - return NULL; - } - - qoi_write_32(bytes, &p, QOI_MAGIC); - qoi_write_32(bytes, &p, desc->width); - qoi_write_32(bytes, &p, desc->height); - bytes[p++] = desc->channels; - bytes[p++] = desc->colorspace; - - - pixels = (const unsigned char *)data; - - QOI_ZEROARR(index); - - run = 0; - px_prev.rgba.r = 0; - px_prev.rgba.g = 0; - px_prev.rgba.b = 0; - px_prev.rgba.a = 255; - px = px_prev; - - px_len = desc->width * desc->height * desc->channels; - px_end = px_len - desc->channels; - channels = desc->channels; - - for (px_pos = 0; px_pos < px_len; px_pos += channels) { - px.rgba.r = pixels[px_pos + 0]; - px.rgba.g = pixels[px_pos + 1]; - px.rgba.b = pixels[px_pos + 2]; - - if (channels == 4) { - px.rgba.a = pixels[px_pos + 3]; - } - - if (px.v == px_prev.v) { - run++; - if (run == 62 || px_pos == px_end) { - bytes[p++] = QOI_OP_RUN | (run - 1); - run = 0; - } - } - else { - int index_pos; - - if (run > 0) { - bytes[p++] = QOI_OP_RUN | (run - 1); - run = 0; - } - - index_pos = QOI_COLOR_HASH(px) % 64; - - if (index[index_pos].v == px.v) { - bytes[p++] = QOI_OP_INDEX | index_pos; - } - else { - index[index_pos] = px; - - if (px.rgba.a == px_prev.rgba.a) { - signed char vr = px.rgba.r - px_prev.rgba.r; - signed char vg = px.rgba.g - px_prev.rgba.g; - signed char vb = px.rgba.b - px_prev.rgba.b; - - signed char vg_r = vr - vg; - signed char vg_b = vb - vg; - - if ( - vr > -3 && vr < 2 && - vg > -3 && vg < 2 && - vb > -3 && vb < 2 - ) { - bytes[p++] = QOI_OP_DIFF | (vr + 2) << 4 | (vg + 2) << 2 | (vb + 2); - } - else if ( - vg_r > -9 && vg_r < 8 && - vg > -33 && vg < 32 && - vg_b > -9 && vg_b < 8 - ) { - bytes[p++] = QOI_OP_LUMA | (vg + 32); - bytes[p++] = (vg_r + 8) << 4 | (vg_b + 8); - } - else { - bytes[p++] = QOI_OP_RGB; - bytes[p++] = px.rgba.r; - bytes[p++] = px.rgba.g; - bytes[p++] = px.rgba.b; - } - } - else { - bytes[p++] = QOI_OP_RGBA; - bytes[p++] = px.rgba.r; - bytes[p++] = px.rgba.g; - bytes[p++] = px.rgba.b; - bytes[p++] = px.rgba.a; - } - } - } - px_prev = px; - } - - for (i = 0; i < (int)sizeof(qoi_padding); i++) { - bytes[p++] = qoi_padding[i]; - } - - *out_len = p; - return bytes; -} - -void *qoi_decode(const void *data, int size, qoi_desc *desc, int channels) { - const unsigned char *bytes; - unsigned int header_magic; - unsigned char *pixels; - qoi_rgba_t index[64]; - qoi_rgba_t px; - int px_len, chunks_len, px_pos; - int p = 0, run = 0; - - if ( - data == NULL || desc == NULL || - (channels != 0 && channels != 3 && channels != 4) || - size < QOI_HEADER_SIZE + (int)sizeof(qoi_padding) - ) { - return NULL; - } - - bytes = (const unsigned char *)data; - - header_magic = qoi_read_32(bytes, &p); - desc->width = qoi_read_32(bytes, &p); - desc->height = qoi_read_32(bytes, &p); - desc->channels = bytes[p++]; - desc->colorspace = bytes[p++]; - - if ( - desc->width == 0 || desc->height == 0 || - desc->channels < 3 || desc->channels > 4 || - desc->colorspace > 1 || - header_magic != QOI_MAGIC || - desc->height >= QOI_PIXELS_MAX / desc->width - ) { - return NULL; - } - - if (channels == 0) { - channels = desc->channels; - } - - px_len = desc->width * desc->height * channels; - pixels = (unsigned char *) QOI_MALLOC(px_len); - if (!pixels) { - return NULL; - } - - QOI_ZEROARR(index); - px.rgba.r = 0; - px.rgba.g = 0; - px.rgba.b = 0; - px.rgba.a = 255; - - chunks_len = size - (int)sizeof(qoi_padding); - for (px_pos = 0; px_pos < px_len; px_pos += channels) { - if (run > 0) { - run--; - } - else if (p < chunks_len) { - int b1 = bytes[p++]; - - if (b1 == QOI_OP_RGB) { - px.rgba.r = bytes[p++]; - px.rgba.g = bytes[p++]; - px.rgba.b = bytes[p++]; - } - else if (b1 == QOI_OP_RGBA) { - px.rgba.r = bytes[p++]; - px.rgba.g = bytes[p++]; - px.rgba.b = bytes[p++]; - px.rgba.a = bytes[p++]; - } - else if ((b1 & QOI_MASK_2) == QOI_OP_INDEX) { - px = index[b1]; - } - else if ((b1 & QOI_MASK_2) == QOI_OP_DIFF) { - px.rgba.r += ((b1 >> 4) & 0x03) - 2; - px.rgba.g += ((b1 >> 2) & 0x03) - 2; - px.rgba.b += ( b1 & 0x03) - 2; - } - else if ((b1 & QOI_MASK_2) == QOI_OP_LUMA) { - int b2 = bytes[p++]; - int vg = (b1 & 0x3f) - 32; - px.rgba.r += vg - 8 + ((b2 >> 4) & 0x0f); - px.rgba.g += vg; - px.rgba.b += vg - 8 + (b2 & 0x0f); - } - else if ((b1 & QOI_MASK_2) == QOI_OP_RUN) { - run = (b1 & 0x3f); - } - - index[QOI_COLOR_HASH(px) % 64] = px; - } - - pixels[px_pos + 0] = px.rgba.r; - pixels[px_pos + 1] = px.rgba.g; - pixels[px_pos + 2] = px.rgba.b; - - if (channels == 4) { - pixels[px_pos + 3] = px.rgba.a; - } - } - - return pixels; -} - -#ifndef QOI_NO_STDIO -#include <stdio.h> - -int qoi_write(const char *filename, const void *data, const qoi_desc *desc) { - FILE *f = fopen(filename, "wb"); - int size; - void *encoded; - - if (!f) { - return 0; - } - - encoded = qoi_encode(data, desc, &size); - if (!encoded) { - fclose(f); - return 0; - } - - fwrite(encoded, 1, size, f); - fclose(f); - - QOI_FREE(encoded); - return size; -} - -void *qoi_read(const char *filename, qoi_desc *desc, int channels) { - FILE *f = fopen(filename, "rb"); - int size, bytes_read; - void *pixels, *data; - - if (!f) { - return NULL; - } - - fseek(f, 0, SEEK_END); - size = ftell(f); - if (size <= 0) { - fclose(f); - return NULL; - } - fseek(f, 0, SEEK_SET); - - data = QOI_MALLOC(size); - if (!data) { - fclose(f); - return NULL; - } - - bytes_read = fread(data, 1, size, f); - fclose(f); - - pixels = qoi_decode(data, bytes_read, desc, channels); - QOI_FREE(data); - return pixels; -} - -#endif /* QOI_NO_STDIO */ -#endif /* QOI_IMPLEMENTATION */ |