X-Git-Url: https://harrygodden.com/git/?p=fishladder.git;a=blobdiff_plain;f=phoboslab%2Fqoi_old.h;fp=phoboslab%2Fqoi_old.h;h=d70e2e8557dff2e54a6a165d63f9ae54c7c853e0;hp=0000000000000000000000000000000000000000;hb=3cb144985169da3cea1c21a7b0bfba8d43c28fdb;hpb=aa435c13e7184bcd2034b8af1b20db1063baf9ec diff --git a/phoboslab/qoi_old.h b/phoboslab/qoi_old.h new file mode 100644 index 0000000..d70e2e8 --- /dev/null +++ b/phoboslab/qoi_old.h @@ -0,0 +1,632 @@ +/* + +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 + +#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 + +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 +