+++ /dev/null
-/*
-
-QOI - The "Quite OK Image" format for fast, lossless image compression
-
-Dominic Szablewski - https://phoboslab.org
-
-
--- LICENSE: The MIT License(MIT)
-
-Copyright(c) 2021 Dominic Szablewski
-
-Permission is hereby granted, free of charge, to any person obtaining a copy of
-this software and associated documentation files(the "Software"), to deal in
-the Software without restriction, including without limitation the rights to
-use, copy, modify, merge, publish, distribute, sublicense, and / or sell copies
-of the Software, and to permit persons to whom the Software is furnished to do
-so, subject to the following conditions :
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.IN NO EVENT SHALL THE
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.
-
-
--- About
-
-QOI encodes and decodes images in a lossless format. An encoded QOI image is
-usually around 10--30% larger than a decently optimized PNG image.
-
-QOI outperforms simpler PNG encoders in compression ratio and performance. QOI
-images are typically 20% smaller than PNGs written with stbi_image. Encoding is
-25-50x faster and decoding is 3-4x faster than stbi_image or libpng.
-
-
--- 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){
- .width = 1920,
- .height = 1080,
- .channels = 4,
- .colorspace = QOI_SRGB
-});
-
-// Load and decode a QOI image from the file system into a 32bbp RGBA buffer.
-// The qoi_desc struct will be filled with the width, height, number of channels
-// and colorspace read from the file header.
-qoi_desc desc;
-void *rgba_pixels = qoi_read("image.qoi", &desc, 4);
-
-
-
--- Documentation
-
-This library provides the following functions;
-- qoi_read -- read and decode a QOI file
-- qoi_decode -- decode the raw bytes of a QOI image from memory
-- qoi_write -- encode and write a QOI file
-- qoi_encode -- encode an rgba buffer into a QOI image in memory
-
-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.
-
-
--- Data Format
-
-A QOI file has a 14 byte header, followed by any number of data "chunks".
-
-struct qoi_header_t {
- char magic[4]; // magic bytes "qoif"
- uint32_t width; // image width in pixels (BE)
- uint32_t height; // image height in pixels (BE)
- uint8_t channels; // must be 3 (RGB) or 4 (RGBA)
- uint8_t colorspace; // a bitmap 0000rgba where
- // - a zero bit indicates sRGBA,
- // - a one bit indicates linear (user interpreted)
- // colorspace for each channel
-};
-
-The decoder and encoder start with {r: 0, g: 0, b: 0, a: 255} as the previous
-pixel value. Pixels are either encoded as
- - a run of the previous pixel
- - an index into a previously seen pixel
- - a difference to the previous pixel value in r,g,b,a
- - full r,g,b,a values
-
-A running array[64] of previously seen pixel values is maintained by the encoder
-and decoder. Each pixel that is seen by the encoder and decoder is put into this
-array at the position (r^g^b^a) % 64. In the encoder, if the pixel value at this
-index matches the current pixel, this index position is written to the stream.
-
-Each chunk starts with a 2, 3 or 4 bit tag, followed by a number of data bits.
-The bit length of chunks is divisible by 8 - i.e. all chunks are byte aligned.
-All values encoded in these data bits have the most significant bit (MSB) on the
-left.
-
-The possible chunks are:
-
- - QOI_INDEX -------------
-| Byte[0] |
-| 7 6 5 4 3 2 1 0 |
-|-------+-----------------|
-| 0 0 | index |
-
-2-bit tag b00
-6-bit index into the color index array: 0..63
-
-
- - QOI_RUN_8 -------------
-| Byte[0] |
-| 7 6 5 4 3 2 1 0 |
-|----------+--------------|
-| 0 1 0 | run |
-
-3-bit tag b010
-5-bit run-length repeating the previous pixel: 1..32
-
-
- - QOI_RUN_16 --------------------------------------
-| Byte[0] | Byte[1] |
-| 7 6 5 4 3 2 1 0 | 7 6 5 4 3 2 1 0 |
-|----------+----------------------------------------|
-| 0 1 1 | run |
-
-3-bit tag b011
-13-bit run-length repeating the previous pixel: 33..8224
-
-
- - QOI_DIFF_8 ------------
-| Byte[0] |
-| 7 6 5 4 3 2 1 0 |
-|-------+-----+-----+-----|
-| 1 0 | dr | db | bg |
-
-2-bit tag b10
-2-bit red channel difference from the previous pixel between -2..1
-2-bit green channel difference from the previous pixel between -2..1
-2-bit blue channel difference from the previous pixel between -2..1
-
-The difference to the current channel values are using a wraparound operation,
-so "1 - 2" will result in 255, while "255 + 1" will result in 0.
-
-
- - QOI_DIFF_16 -------------------------------------
-| Byte[0] | Byte[1] |
-| 7 6 5 4 3 2 1 0 | 7 6 5 4 3 2 1 0 |
-|----------+--------------|------------ +-----------|
-| 1 1 0 | red diff | green diff | blue diff |
-
-3-bit tag b110
-5-bit red channel difference from the previous pixel between -16..15
-4-bit green channel difference from the previous pixel between -8..7
-4-bit blue channel difference from the previous pixel between -8..7
-
-The difference to the current channel values are using a wraparound operation,
-so "10 - 13" will result in 253, while "250 + 7" will result in 1.
-
-
- - QOI_DIFF_24 ---------------------------------------------------------------
-| Byte[0] | Byte[1] | Byte[2] |
-| 7 6 5 4 3 2 1 0 | 7 6 5 4 3 2 1 0 | 7 6 5 4 3 2 1 0 |
-|-------------+----------------+--------------+----------------+--------------|
-| 1 1 1 0 | red diff | green diff | blue diff | alpha diff |
-
-4-bit tag b1110
-5-bit red channel difference from the previous pixel between -16..15
-5-bit green channel difference from the previous pixel between -16..15
-5-bit blue channel difference from the previous pixel between -16..15
-5-bit alpha channel difference from the previous pixel between -16..15
-
-The difference to the current channel values are using a wraparound operation,
-so "10 - 13" will result in 253, while "250 + 7" will result in 1.
-
-
- - QOI_COLOR -------------
-| Byte[0] |
-| 7 6 5 4 3 2 1 0 |
-|-------------+--+--+--+--|
-| 1 1 1 1 |hr|hg|hb|ha|
-
-4-bit tag b1111
-1-bit red byte follows
-1-bit green byte follows
-1-bit blue byte follows
-1-bit alpha byte follows
-
-For each set bit hr, hg, hb and ha another byte follows in this order. If such a
-byte follows, it will replace the current color channel value with the value of
-this byte.
-
-
-The byte stream is padded at the end with 4 zero bytes. Size the longest chunk
-we can encounter is 5 bytes (QOI_COLOR with RGBA set), with this padding we just
-have to check for an overrun once per decode loop iteration.
-
-*/
-
-
-// -----------------------------------------------------------------------------
-// Header - Public functions
-
-#ifndef QOI_H
-#define QOI_H
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-// A pointer to qoi_desc struct has to be supplied to all of qoi's functions. It
-// describes either the input format (for qoi_write, qoi_encode), or is filled
-// with the description read from the file header (for qoi_read, qoi_decode).
-
-// The colorspace in this qoi_desc is a bitmap with 0000rgba where a 0-bit
-// indicates sRGB and a 1-bit indicates linear colorspace for each channel. You
-// may use one of the predefined constants: QOI_SRGB, QOI_SRGB_LINEAR_ALPHA or
-// QOI_LINEAR. The colorspace is purely informative. It will be saved to the
-// file header, but does not affect en-/decoding in any way.
-
-#define QOI_SRGB 0x00
-#define QOI_SRGB_LINEAR_ALPHA 0x01
-#define QOI_LINEAR 0x0f
-
-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
-
-
-// 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.
-
-void *qoi_encode(const void *data, const qoi_desc *desc, int *out_len);
-
-
-// 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);
-
-
-#ifdef __cplusplus
-}
-#endif
-#endif // QOI_H
-
-
-// -----------------------------------------------------------------------------
-// Implementation
-
-#ifdef QOI_IMPLEMENTATION
-#include <stdlib.h>
-
-#ifndef QOI_MALLOC
- #define QOI_MALLOC(sz) malloc(sz)
- #define QOI_FREE(p) free(p)
-#endif
-
-#define QOI_INDEX 0x00 // 00xxxxxx
-#define QOI_RUN_8 0x40 // 010xxxxx
-#define QOI_RUN_16 0x60 // 011xxxxx
-#define QOI_DIFF_8 0x80 // 10xxxxxx
-#define QOI_DIFF_16 0xc0 // 110xxxxx
-#define QOI_DIFF_24 0xe0 // 1110xxxx
-#define QOI_COLOR 0xf0 // 1111xxxx
-
-#define QOI_MASK_2 0xc0 // 11000000
-#define QOI_MASK_3 0xe0 // 11100000
-#define QOI_MASK_4 0xf0 // 11110000
-
-#define QOI_COLOR_HASH(C) (C.rgba.r ^ C.rgba.g ^ C.rgba.b ^ C.rgba.a)
-#define QOI_MAGIC \
- (((unsigned int)'q') << 24 | ((unsigned int)'o') << 16 | \
- ((unsigned int)'i') << 8 | ((unsigned int)'f'))
-#define QOI_HEADER_SIZE 14
-#define QOI_PADDING 4
-
-typedef union {
- struct { unsigned char r, g, b, a; } rgba;
- unsigned int v;
-} qoi_rgba_t;
-
-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);
-}
-
-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) {
- if (
- data == NULL || out_len == NULL || desc == NULL ||
- desc->width == 0 || desc->height == 0 ||
- desc->channels < 3 || desc->channels > 4 ||
- (desc->colorspace & 0xf0) != 0
- ) {
- return NULL;
- }
-
- int max_size =
- desc->width * desc->height * (desc->channels + 1) +
- QOI_HEADER_SIZE + QOI_PADDING;
-
- int p = 0;
- unsigned char *bytes = 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;
-
-
- const unsigned char *pixels = (const unsigned char *)data;
-
- qoi_rgba_t index[64] = {0};
-
- int run = 0;
- qoi_rgba_t px_prev = {.rgba = {.r = 0, .g = 0, .b = 0, .a = 255}};
- qoi_rgba_t px = px_prev;
-
- int px_len = desc->width * desc->height * desc->channels;
- int px_end = px_len - desc->channels;
- int channels = desc->channels;
-
- for (int px_pos = 0; px_pos < px_len; px_pos += channels) {
- if (channels == 4) {
- px = *(qoi_rgba_t *)(pixels + px_pos);
- }
- else {
- px.rgba.r = pixels[px_pos];
- px.rgba.g = pixels[px_pos+1];
- px.rgba.b = pixels[px_pos+2];
- }
-
- if (px.v == px_prev.v) {
- run++;
- }
-
- if (
- run > 0 &&
- (run == 0x2020 || px.v != px_prev.v || px_pos == px_end)
- ) {
- if (run < 33) {
- run -= 1;
- bytes[p++] = QOI_RUN_8 | run;
- }
- else {
- run -= 33;
- bytes[p++] = QOI_RUN_16 | run >> 8;
- bytes[p++] = run;
- }
- run = 0;
- }
-
- if (px.v != px_prev.v) {
- int index_pos = QOI_COLOR_HASH(px) % 64;
-
- if (index[index_pos].v == px.v) {
- bytes[p++] = QOI_INDEX | index_pos;
- }
- else {
- index[index_pos] = px;
-
- int vr = px.rgba.r - px_prev.rgba.r;
- int vg = px.rgba.g - px_prev.rgba.g;
- int vb = px.rgba.b - px_prev.rgba.b;
- int va = px.rgba.a - px_prev.rgba.a;
-
- if (
- vr > -17 && vr < 16 &&
- vg > -17 && vg < 16 &&
- vb > -17 && vb < 16 &&
- va > -17 && va < 16
- ) {
- if (
- va == 0 &&
- vr > -3 && vr < 2 &&
- vg > -3 && vg < 2 &&
- vb > -3 && vb < 2
- ) {
- bytes[p++] = QOI_DIFF_8 | ((vr + 2) << 4) | (vg + 2) << 2 | (vb + 2);
- }
- else if (
- va == 0 &&
- vr > -17 && vr < 16 &&
- vg > -9 && vg < 8 &&
- vb > -9 && vb < 8
- ) {
- bytes[p++] = QOI_DIFF_16 | (vr + 16);
- bytes[p++] = (vg + 8) << 4 | (vb + 8);
- }
- else {
- bytes[p++] = QOI_DIFF_24 | (vr + 16) >> 1;
- bytes[p++] = (vr + 16) << 7 | (vg + 16) << 2 | (vb + 16) >> 3;
- bytes[p++] = (vb + 16) << 5 | (va + 16);
- }
- }
- else {
- bytes[p++] = QOI_COLOR | (vr ? 8 : 0) | (vg ? 4 : 0) | (vb ? 2 : 0) | (va ? 1 : 0);
- if (vr) { bytes[p++] = px.rgba.r; }
- if (vg) { bytes[p++] = px.rgba.g; }
- if (vb) { bytes[p++] = px.rgba.b; }
- if (va) { bytes[p++] = px.rgba.a; }
- }
- }
- }
- px_prev = px;
- }
-
- for (int i = 0; i < QOI_PADDING; i++) {
- bytes[p++] = 0;
- }
-
- *out_len = p;
- return bytes;
-}
-
-void *qoi_decode(const void *data, int size, qoi_desc *desc, int channels) {
- if (
- data == NULL || desc == NULL ||
- (channels != 0 && channels != 3 && channels != 4) ||
- size < QOI_HEADER_SIZE + QOI_PADDING
- ) {
- return NULL;
- }
-
- const unsigned char *bytes = (const unsigned char *)data;
- int p = 0;
-
- unsigned int 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 ||
- header_magic != QOI_MAGIC
- ) {
- return NULL;
- }
-
- if (channels == 0) {
- channels = desc->channels;
- }
-
- int px_len = desc->width * desc->height * channels;
- unsigned char *pixels = QOI_MALLOC(px_len);
- if (!pixels) {
- return NULL;
- }
-
- qoi_rgba_t px = {.rgba = {.r = 0, .g = 0, .b = 0, .a = 255}};
- qoi_rgba_t index[64] = {0};
-
- int run = 0;
- int chunks_len = size - QOI_PADDING;
- for (int 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_MASK_2) == QOI_INDEX) {
- px = index[b1 ^ QOI_INDEX];
- }
- else if ((b1 & QOI_MASK_3) == QOI_RUN_8) {
- run = (b1 & 0x1f);
- }
- else if ((b1 & QOI_MASK_3) == QOI_RUN_16) {
- int b2 = bytes[p++];
- run = (((b1 & 0x1f) << 8) | (b2)) + 32;
- }
- else if ((b1 & QOI_MASK_2) == QOI_DIFF_8) {
- 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_3) == QOI_DIFF_16) {
- int b2 = bytes[p++];
- px.rgba.r += (b1 & 0x1f) - 16;
- px.rgba.g += (b2 >> 4) - 8;
- px.rgba.b += (b2 & 0x0f) - 8;
- }
- else if ((b1 & QOI_MASK_4) == QOI_DIFF_24) {
- int b2 = bytes[p++];
- int b3 = bytes[p++];
- px.rgba.r += (((b1 & 0x0f) << 1) | (b2 >> 7)) - 16;
- px.rgba.g += ((b2 & 0x7c) >> 2) - 16;
- px.rgba.b += (((b2 & 0x03) << 3) | ((b3 & 0xe0) >> 5)) - 16;
- px.rgba.a += (b3 & 0x1f) - 16;
- }
- else if ((b1 & QOI_MASK_4) == QOI_COLOR) {
- if (b1 & 8) { px.rgba.r = bytes[p++]; }
- if (b1 & 4) { px.rgba.g = bytes[p++]; }
- if (b1 & 2) { px.rgba.b = bytes[p++]; }
- if (b1 & 1) { px.rgba.a = bytes[p++]; }
- }
-
- index[QOI_COLOR_HASH(px) % 64] = px;
- }
-
- if (channels == 4) {
- *(qoi_rgba_t*)(pixels + px_pos) = px;
- }
- else {
- pixels[px_pos] = px.rgba.r;
- pixels[px_pos+1] = px.rgba.g;
- pixels[px_pos+2] = px.rgba.b;
- }
- }
-
- 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");
- if (!f) {
- return 0;
- }
-
- int size;
- void *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");
- if (!f) {
- return NULL;
- }
-
- fseek(f, 0, SEEK_END);
- int size = ftell(f);
- fseek(f, 0, SEEK_SET);
-
- void *data = QOI_MALLOC(size);
- if (!data) {
- fclose(f);
- return NULL;
- }
-
- int bytes_read = fread(data, 1, size, f);
- fclose(f);
-
- void *pixels = qoi_decode(data, bytes_read, desc, channels);
- QOI_FREE(data);
- return pixels;
-}
-
-#endif // QOI_NO_STDIO
-#endif // QOI_IMPLEMENTATION
-
projects / fishladder.git / blobdiff