|
|
@ -28,13 +28,9 @@ 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 but 10% |
|
|
|
larger than with libpng. Encoding is 25-50x faster and decoding is 3-4x faster |
|
|
|
than stbi_image or libpng. |
|
|
|
QOI encodes and decodes images in a lossless format. Compared to stb_image and |
|
|
|
stb_image_write QOI offers 20x-50x faster encoding, 3x-4x faster decoding and |
|
|
|
20% better compression. |
|
|
|
|
|
|
|
|
|
|
|
-- Synopsis |
|
|
@ -78,95 +74,156 @@ 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. |
|
|
|
|
|
|
|
This library uses memset() to zero-initialize the index. To supply your own |
|
|
|
implementation you can define QOI_ZEROARR before including this library. |
|
|
|
|
|
|
|
|
|
|
|
-- Data Format |
|
|
|
|
|
|
|
A QOI file has a 14 byte header, followed by any number of data "chunks". |
|
|
|
A QOI file has a 14 byte header, followed by any number of data "chunks" and an |
|
|
|
8-byte end marker. |
|
|
|
|
|
|
|
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 |
|
|
|
uint8_t channels; // 3 = RGB, 4 = RGBA |
|
|
|
uint8_t colorspace; // 0 = sRGB with linear alpha, 1 = all channels linear |
|
|
|
}; |
|
|
|
|
|
|
|
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. |
|
|
|
|
|
|
|
QOI_INDEX { |
|
|
|
u8 tag : 2; // b00 |
|
|
|
u8 idx : 6; // 6-bit index into the color index array: 0..63 |
|
|
|
} |
|
|
|
|
|
|
|
QOI_RUN_8 { |
|
|
|
u8 tag : 3; // b010 |
|
|
|
u8 run : 5; // 5-bit run-length repeating the previous pixel: 1..32 |
|
|
|
} |
|
|
|
|
|
|
|
QOI_RUN_16 { |
|
|
|
u8 tag : 3; // b011 |
|
|
|
u16 run : 13; // 13-bit run-length repeating the previous pixel: 33..8224 |
|
|
|
} |
|
|
|
|
|
|
|
QOI_DIFF_8 { |
|
|
|
u8 tag : 2; // b10 |
|
|
|
u8 dr : 2; // 2-bit red channel difference: -2..1 |
|
|
|
u8 dg : 2; // 2-bit green channel difference: -2..1 |
|
|
|
u8 db : 2; // 2-bit blue channel difference: -2..1 |
|
|
|
} |
|
|
|
Images are encoded from top to bottom, left to right. The decoder and encoder |
|
|
|
start with {r: 0, g: 0, b: 0, a: 255} as the previous pixel value. An image is |
|
|
|
complete when all pixels specified by width * height have been covered. |
|
|
|
|
|
|
|
QOI_DIFF_16 { |
|
|
|
u8 tag : 3; // b110 |
|
|
|
u8 dr : 5; // 5-bit red channel difference: -16..15 |
|
|
|
u8 dg : 4; // 4-bit green channel difference: -8.. 7 |
|
|
|
u8 db : 4; // 4-bit blue channel difference: -8.. 7 |
|
|
|
} |
|
|
|
|
|
|
|
QOI_DIFF_24 { |
|
|
|
u8 tag : 4; // b1110 |
|
|
|
u8 dr : 5; // 5-bit red channel difference: -16..15 |
|
|
|
u8 dg : 5; // 5-bit green channel difference: -16..15 |
|
|
|
u8 db : 5; // 5-bit blue channel difference: -16..15 |
|
|
|
u8 da : 5; // 5-bit alpha channel difference: -16..15 |
|
|
|
} |
|
|
|
|
|
|
|
QOI_COLOR { |
|
|
|
u8 tag : 4; // b1111 |
|
|
|
u8 has_r: 1; // red byte follows |
|
|
|
u8 has_g: 1; // green byte follows |
|
|
|
u8 has_b: 1; // blue byte follows |
|
|
|
u8 has_a: 1; // alpha byte follows |
|
|
|
u8 r; // red value if has_r == 1: 0..255 |
|
|
|
u8 g; // green value if has_g == 1: 0..255 |
|
|
|
u8 b; // blue value if has_b == 1: 0..255 |
|
|
|
u8 a; // alpha value if has_a == 1: 0..255 |
|
|
|
} |
|
|
|
|
|
|
|
The byte stream is padded 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. |
|
|
|
Pixels are encoded as |
|
|
|
- a run of the previous pixel |
|
|
|
- an index into an array of previously seen pixels |
|
|
|
- a difference to the previous pixel value in r,g,b |
|
|
|
- full r,g,b or r,g,b,a values |
|
|
|
|
|
|
|
The color channels are assumed to not be premultiplied with the alpha channel |
|
|
|
("un-premultiplied alpha"). |
|
|
|
|
|
|
|
A running array[64] (zero-initialized) 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 formed by a hash function of |
|
|
|
the color value. In the encoder, if the pixel value at the index matches the |
|
|
|
current pixel, this index position is written to the stream as QOI_OP_INDEX. |
|
|
|
The hash function for the index is: |
|
|
|
|
|
|
|
index_position = (r * 3 + g * 5 + b * 7 + a * 11) % 64 |
|
|
|
|
|
|
|
Each chunk starts with a 2- or 8-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 on the left. |
|
|
|
|
|
|
|
The 8-bit tags have precedence over the 2-bit tags. A decoder must check for the |
|
|
|
presence of an 8-bit tag first. |
|
|
|
|
|
|
|
The byte stream's end is marked with 7 0x00 bytes followed a single 0x01 byte. |
|
|
|
|
|
|
|
|
|
|
|
The possible chunks are: |
|
|
|
|
|
|
|
|
|
|
|
.- QOI_OP_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 |
|
|
|
|
|
|
|
A valid encoder must not issue 7 or more consecutive QOI_OP_INDEX chunks to the |
|
|
|
index 0, to avoid confusion with the 8 byte end marker. |
|
|
|
|
|
|
|
|
|
|
|
.- QOI_OP_DIFF -----------. |
|
|
|
| Byte[0] | |
|
|
|
| 7 6 5 4 3 2 1 0 | |
|
|
|
|-------+-----+-----+-----| |
|
|
|
| 0 1 | dr | dg | db | |
|
|
|
`-------------------------` |
|
|
|
2-bit tag b01 |
|
|
|
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. |
|
|
|
|
|
|
|
Values are stored as unsigned integers with a bias of 2. E.g. -2 is stored as |
|
|
|
0 (b00). 1 is stored as 3 (b11). |
|
|
|
|
|
|
|
|
|
|
|
.- QOI_OP_LUMA -------------------------------------. |
|
|
|
| Byte[0] | Byte[1] | |
|
|
|
| 7 6 5 4 3 2 1 0 | 7 6 5 4 3 2 1 0 | |
|
|
|
|-------+-----------------+-------------+-----------| |
|
|
|
| 1 0 | green diff | dr - dg | db - dg | |
|
|
|
`---------------------------------------------------` |
|
|
|
2-bit tag b10 |
|
|
|
6-bit green channel difference from the previous pixel -32..31 |
|
|
|
4-bit red channel difference minus green channel difference -8..7 |
|
|
|
4-bit blue channel difference minus green channel difference -8..7 |
|
|
|
|
|
|
|
The green channel is used to indicate the general direction of change and is |
|
|
|
encoded in 6 bits. The red and blue channels (dr and db) base their diffs off |
|
|
|
of the green channel difference and are encoded in 4 bits. I.e.: |
|
|
|
dr_dg = (last_px.r - cur_px.r) - (last_px.g - cur_px.g) |
|
|
|
db_dg = (last_px.b - cur_px.b) - (last_px.g - cur_px.g) |
|
|
|
|
|
|
|
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. |
|
|
|
|
|
|
|
Values are stored as unsigned integers with a bias of 32 for the green channel |
|
|
|
and a bias of 8 for the red and blue channel. |
|
|
|
|
|
|
|
|
|
|
|
.- QOI_OP_RUN ------------. |
|
|
|
| Byte[0] | |
|
|
|
| 7 6 5 4 3 2 1 0 | |
|
|
|
|-------+-----------------| |
|
|
|
| 1 1 | run | |
|
|
|
`-------------------------` |
|
|
|
2-bit tag b11 |
|
|
|
6-bit run-length repeating the previous pixel: 1..62 |
|
|
|
|
|
|
|
The run-length is stored with a bias of -1. Note that the run-lengths 63 and 64 |
|
|
|
(b111110 and b111111) are illegal as they are occupied by the QOI_OP_RGB and |
|
|
|
QOI_OP_RGBA tags. |
|
|
|
|
|
|
|
|
|
|
|
.- QOI_OP_RGB ------------------------------------------. |
|
|
|
| Byte[0] | Byte[1] | Byte[2] | Byte[3] | |
|
|
|
| 7 6 5 4 3 2 1 0 | 7 .. 0 | 7 .. 0 | 7 .. 0 | |
|
|
|
|-------------------------+---------+---------+---------| |
|
|
|
| 1 1 1 1 1 1 1 0 | red | green | blue | |
|
|
|
`-------------------------------------------------------` |
|
|
|
8-bit tag b11111110 |
|
|
|
8-bit red channel value |
|
|
|
8-bit green channel value |
|
|
|
8-bit blue channel value |
|
|
|
|
|
|
|
|
|
|
|
.- QOI_OP_RGBA ---------------------------------------------------. |
|
|
|
| Byte[0] | Byte[1] | Byte[2] | Byte[3] | Byte[4] | |
|
|
|
| 7 6 5 4 3 2 1 0 | 7 .. 0 | 7 .. 0 | 7 .. 0 | 7 .. 0 | |
|
|
|
|-------------------------+---------+---------+---------+---------| |
|
|
|
| 1 1 1 1 1 1 1 1 | red | green | blue | alpha | |
|
|
|
`-----------------------------------------------------------------` |
|
|
|
8-bit tag b11111111 |
|
|
|
8-bit red channel value |
|
|
|
8-bit green channel value |
|
|
|
8-bit blue channel value |
|
|
|
8-bit alpha channel value |
|
|
|
|
|
|
|
*/ |
|
|
|
|
|
|
|
|
|
|
|
// ----------------------------------------------------------------------------- |
|
|
|
// Header - Public functions |
|
|
|
cm">/* ----------------------------------------------------------------------------- |
|
|
|
Header - Public functions */ |
|
|
|
|
|
|
|
#ifndef QOI_H |
|
|
|
#define QOI_H |
|
|
@ -175,19 +232,20 @@ to check for an overrun once per decode loop iteration. |
|
|
|
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). |
|
|
|
/* 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 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. |
|
|
|
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 |
|
|
|
en-/decoding in any way. */ |
|
|
|
|
|
|
|
#define QOI_SRGB 0x00 |
|
|
|
#define QOI_SRGB_LINEAR_ALPHA 0x01 |
|
|
|
#define QOI_LINEAR 0x0f |
|
|
|
#define QOI_SRGB 0 |
|
|
|
#define QOI_LINEAR 1 |
|
|
|
|
|
|
|
typedef struct { |
|
|
|
unsigned int width; |
|
|
@ -198,49 +256,49 @@ typedef struct { |
|
|
|
|
|
|
|
#ifndef QOI_NO_STDIO |
|
|
|
|
|
|
|
o">// 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. |
|
|
|
cm">/* 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. |
|
|
|
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); |
|
|
|
|
|
|
|
|
|
|
|
o">// 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. |
|
|
|
cm">/* 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 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. |
|
|
|
The returned pixel data should be free()d after use. */ |
|
|
|
|
|
|
|
void *qoi_read(const char *filename, qoi_desc *desc, int channels); |
|
|
|
|
|
|
|
#endif p">// QOI_NO_STDIO |
|
|
|
#endif m">/* QOI_NO_STDIO */ |
|
|
|
|
|
|
|
|
|
|
|
o">// Encode raw RGB or RGBA pixels into a QOI image in memory. |
|
|
|
cm">/* 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 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 user. |
|
|
|
The returned qoi data should be free()d after use. */ |
|
|
|
|
|
|
|
void *qoi_encode(const void *data, const qoi_desc *desc, int *out_len); |
|
|
|
|
|
|
|
|
|
|
|
o">// Decode a QOI image from memory. |
|
|
|
cm">/* 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 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. |
|
|
|
The returned pixel data should be free()d after use. */ |
|
|
|
|
|
|
|
void *qoi_decode(const void *data, int size, qoi_desc *desc, int channels); |
|
|
|
|
|
|
@ -248,44 +306,52 @@ void *qoi_decode(const void *data, int size, qoi_desc *desc, int channels); |
|
|
|
#ifdef __cplusplus |
|
|
|
} |
|
|
|
#endif |
|
|
|
#endif p">// QOI_H |
|
|
|
#endif m">/* QOI_H */ |
|
|
|
|
|
|
|
|
|
|
|
o">// ----------------------------------------------------------------------------- |
|
|
|
o">// Implementation |
|
|
|
cm">/* ----------------------------------------------------------------------------- |
|
|
|
n">Implementation */ |
|
|
|
|
|
|
|
#ifdef QOI_IMPLEMENTATION |
|
|
|
#include <stdlib.h> |
|
|
|
#include <string.h> |
|
|
|
|
|
|
|
#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_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_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_MASK_3 0xe0 // 11100000 |
|
|
|
#define QOI_MASK_4 0xf0 // 11110000 |
|
|
|
#define QOI_MASK_2 0xc0 /* 11000000 */ |
|
|
|
|
|
|
|
#define QOI_COLOR_HASH(C) (C.rgba.r ^ C.rgba.g ^ C.rgba.b ^ C.rgba.a) |
|
|
|
#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 |
|
|
|
#define QOI_PADDING 4 |
|
|
|
|
|
|
|
/* 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}; |
|
|
|
|
|
|
|
void qoi_write_32(unsigned char *bytes, int *p, unsigned int v) { |
|
|
|
bytes[(*p)++] = (0xff000000 & v) >> 24; |
|
|
|
bytes[(*p)++] = (0x00ff0000 & v) >> 16; |
|
|
@ -298,25 +364,33 @@ unsigned int qoi_read_32(const unsigned char *bytes, int *p) { |
|
|
|
unsigned int b = bytes[(*p)++]; |
|
|
|
unsigned int c = bytes[(*p)++]; |
|
|
|
unsigned int d = bytes[(*p)++]; |
|
|
|
return p">(a << 24) | (b << 16) | (c << 8) | d; |
|
|
|
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 & 0xf0) != 0 |
|
|
|
desc->colorspace > 1 || |
|
|
|
desc->height >= QOI_PIXELS_MAX / desc->width |
|
|
|
) { |
|
|
|
return NULL; |
|
|
|
} |
|
|
|
|
|
|
|
kt">int max_size = |
|
|
|
max_size = |
|
|
|
desc->width * desc->height * (desc->channels + 1) + |
|
|
|
QOI_HEADER_SIZE + n">QOI_PADDING; |
|
|
|
QOI_HEADER_SIZE + k">sizeof(qoi_padding); |
|
|
|
|
|
|
|
kt">int p = 0; |
|
|
|
unsigned char *n">bytes = QOI_MALLOC(max_size); |
|
|
|
p = 0; |
|
|
|
n">bytes = (unsigned char *p">) QOI_MALLOC(max_size); |
|
|
|
if (!bytes) { |
|
|
|
return NULL; |
|
|
|
} |
|
|
@ -328,94 +402,98 @@ void *qoi_encode(const void *data, const qoi_desc *desc, int *out_len) { |
|
|
|
bytes[p++] = desc->colorspace; |
|
|
|
|
|
|
|
|
|
|
|
k">const unsigned char *pixels = (const unsigned char *)data; |
|
|
|
pixels = (const unsigned char *)data; |
|
|
|
|
|
|
|
qoi_rgba_t index[64] = {0}; |
|
|
|
QOI_ZEROARR(index); |
|
|
|
|
|
|
|
int run = 0; |
|
|
|
qoi_rgba_t px_prev = {.rgba = {.r = 0, .g = 0, .b = 0, .a = 255}}; |
|
|
|
qoi_rgba_t px = px_prev; |
|
|
|
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; |
|
|
|
|
|
|
|
int px_len = desc->width * desc->height * desc->channels; |
|
|
|
int px_end = px_len - desc->channels; |
|
|
|
for (int px_pos = 0; px_pos < px_len; px_pos += desc->channels) { |
|
|
|
if (desc->channels == 4) { |
|
|
|
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) { |
|
|
|
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]; |
|
|
|
px.rgba.r = pixels[px_pos + 0]; |
|
|
|
px.rgba.g = pixels[px_pos + 1]; |
|
|
|
px.rgba.b = pixels[px_pos + 2]; |
|
|
|
} |
|
|
|
|
|
|
|
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 && (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; |
|
|
|
if (run > 0) { |
|
|
|
bytes[p++] = QOI_OP_RUN | (run - 1); |
|
|
|
run = 0; |
|
|
|
} |
|
|
|
run = 0; |
|
|
|
} |
|
|
|
|
|
|
|
if (px.v != px_prev.v) { |
|
|
|
int index_pos = QOI_COLOR_HASH(px) % 64; |
|
|
|
index_pos = QOI_COLOR_HASH(px) % 64; |
|
|
|
|
|
|
|
if (index[index_pos].v == px.v) { |
|
|
|
bytes[p++] = QOI_INDEX | index_pos; |
|
|
|
bytes[p++] = QOI_OP_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 (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 > -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 |
|
|
|
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); |
|
|
|
bytes[p++] = QOI_OP_DIFF | (vr + 2) << 4 | (vg + 2) << 2 | (vb + 2); |
|
|
|
} |
|
|
|
else if ( |
|
|
|
va == 0 && vr > -17 && vr < 16 && |
|
|
|
vg > -9 && vg < 8 && vb > -9 && vb < 8 |
|
|
|
vg_r > -9 && vg_r < 8 && |
|
|
|
vg > -33 && vg < 32 && |
|
|
|
vg_b > -9 && vg_b < 8 |
|
|
|
) { |
|
|
|
bytes[p++] = QOI_DIFF_16 | (vr + 16); |
|
|
|
bytes[p++] = (p">(vg + 8) << 4) | (vb + 8); |
|
|
|
bytes[p++] = QOI_OP_LUMA | (vg + 32); |
|
|
|
bytes[p++] = (vg_r + 8) << 4 | (vg_b + 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); |
|
|
|
bytes[p++] = QOI_OP_RGB; |
|
|
|
bytes[p++] = px.rgba.r; |
|
|
|
bytes[p++] = px.rgba.g; |
|
|
|
bytes[p++] = px.rgba.b; |
|
|
|
} |
|
|
|
} |
|
|
|
else { |
|
|
|
bytes[p++] = QOI_COLOR | (vr?8:0)|(vg?4:0)|(vb?2:0)|(va?1:0); |
|
|
|
k">if (vr) { bytes[p++] = px.rgba.r; } |
|
|
|
k">if (vg) { bytes[p++] = px.rgba.g; } |
|
|
|
k">if (vb) { bytes[p++] = px.rgba.b; } |
|
|
|
k">if (va) { bytes[p++] = px.rgba.a; } |
|
|
|
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 (kt">int i = 0; i < n">QOI_PADDING; i++) { |
|
|
|
bytes[p++] = mi">0; |
|
|
|
for (i = 0; i < p">(int)sizeof(qoi_padding); i++) { |
|
|
|
bytes[p++] = n">qoi_padding[i]; |
|
|
|
} |
|
|
|
|
|
|
|
*out_len = p; |
|
|
@ -423,18 +501,25 @@ void *qoi_encode(const void *data, const qoi_desc *desc, int *out_len) { |
|
|
|
} |
|
|
|
|
|
|
|
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 + QOI_PADDING |
|
|
|
size < QOI_HEADER_SIZE + p">(int)sizeof(qoi_padding) |
|
|
|
) { |
|
|
|
return NULL; |
|
|
|
} |
|
|
|
|
|
|
|
const unsigned char *bytes = (const unsigned char *)data; |
|
|
|
int p = 0; |
|
|
|
bytes = (const unsigned char *)data; |
|
|
|
|
|
|
|
kt">unsigned int header_magic = qoi_read_32(bytes, &p); |
|
|
|
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++]; |
|
|
@ -443,7 +528,9 @@ void *qoi_decode(const void *data, int size, qoi_desc *desc, int channels) { |
|
|
|
if ( |
|
|
|
desc->width == 0 || desc->height == 0 || |
|
|
|
desc->channels < 3 || desc->channels > 4 || |
|
|
|
header_magic != QOI_MAGIC |
|
|
|
desc->colorspace > 1 || |
|
|
|
header_magic != QOI_MAGIC || |
|
|
|
desc->height >= QOI_PIXELS_MAX / desc->width |
|
|
|
) { |
|
|
|
return NULL; |
|
|
|
} |
|
|
@ -452,58 +539,54 @@ void *qoi_decode(const void *data, int size, qoi_desc *desc, int channels) { |
|
|
|
channels = desc->channels; |
|
|
|
} |
|
|
|
|
|
|
|
kt">int px_len = desc->width * desc->height * channels; |
|
|
|
unsigned char *n">pixels = QOI_MALLOC(px_len); |
|
|
|
px_len = desc->width * desc->height * channels; |
|
|
|
n">pixels = (unsigned char *p">) 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}; |
|
|
|
QOI_ZEROARR(index); |
|
|
|
px.rgba.r = 0; |
|
|
|
px.rgba.g = 0; |
|
|
|
px.rgba.b = 0; |
|
|
|
px.rgba.a = 255; |
|
|
|
|
|
|
|
int run = 0; |
|
|
|
int chunks_len = size - QOI_PADDING; |
|
|
|
for (int px_pos = 0; px_pos < px_len; px_pos += channels) { |
|
|
|
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_MASK_2) == QOI_INDEX) { |
|
|
|
px = index[b1 ^ QOI_INDEX]; |
|
|
|
if (b1 == QOI_OP_RGB) { |
|
|
|
px.rgba.r = bytes[p++]; |
|
|
|
px.rgba.g = bytes[p++]; |
|
|
|
px.rgba.b = bytes[p++]; |
|
|
|
} |
|
|
|
else if ((b1 & QOI_MASK_3) == QOI_RUN_8) { |
|
|
|
run = (b1 & 0x1f); |
|
|
|
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_3) == QOI_RUN_16) { |
|
|
|
int b2 = bytes[p++]; |
|
|
|
run = (((b1 & 0x1f) << 8) | (b2)) + 32; |
|
|
|
else if ((b1 & QOI_MASK_2) == QOI_OP_INDEX) { |
|
|
|
px = index[b1]; |
|
|
|
} |
|
|
|
else if ((b1 & QOI_MASK_2) == QOI_DIFF_8) { |
|
|
|
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_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) { |
|
|
|
else if ((b1 & QOI_MASK_2) == QOI_OP_LUMA) { |
|
|
|
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; |
|
|
|
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_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++]; } |
|
|
|
else if ((b1 & QOI_MASK_2) == QOI_OP_RUN) { |
|
|
|
run = (b1 & 0x3f); |
|
|
|
} |
|
|
|
|
|
|
|
index[QOI_COLOR_HASH(px) % 64] = px; |
|
|
@ -513,9 +596,9 @@ void *qoi_decode(const void *data, int size, qoi_desc *desc, int channels) { |
|
|
|
*(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; |
|
|
|
pixels[px_pos + 0] = px.rgba.r; |
|
|
|
pixels[px_pos + 1] = px.rgba.g; |
|
|
|
pixels[px_pos + 2] = px.rgba.b; |
|
|
|
} |
|
|
|
} |
|
|
|
|
|
|
@ -526,47 +609,57 @@ void *qoi_decode(const void *data, int size, qoi_desc *desc, int channels) { |
|
|
|
#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 = qoi_encode(data, desc, &size); |
|
|
|
if (!encoded) { |
|
|
|
return 0; |
|
|
|
} |
|
|
|
void *encoded; |
|
|
|
|
|
|
|
FILE *f = fopen(filename, "wb"); |
|
|
|
if (!f) { |
|
|
|
QOI_FREE(encoded); |
|
|
|
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); |
|
|
|
int size = ftell(f); |
|
|
|
size = ftell(f); |
|
|
|
if (size <= 0) { |
|
|
|
fclose(f); |
|
|
|
return NULL; |
|
|
|
} |
|
|
|
fseek(f, 0, SEEK_SET); |
|
|
|
|
|
|
|
void *data = QOI_MALLOC(size); |
|
|
|
data = QOI_MALLOC(size); |
|
|
|
if (!data) { |
|
|
|
fclose(f); |
|
|
|
return NULL; |
|
|
|
} |
|
|
|
|
|
|
|
kt">int bytes_read = fread(data, 1, size, f); |
|
|
|
bytes_read = fread(data, 1, size, f); |
|
|
|
fclose(f); |
|
|
|
|
|
|
|
kt">void *pixels = qoi_decode(data, bytes_read, desc, channels); |
|
|
|
pixels = qoi_decode(data, bytes_read, desc, channels); |
|
|
|
QOI_FREE(data); |
|
|
|
return pixels; |
|
|
|
} |
|
|
|
|
|
|
|
#endif p">// QOI_NO_STDIO |
|
|
|
#endif p">// QOI_IMPLEMENTATION |
|
|
|
#endif m">/* QOI_NO_STDIO */ |
|
|
|
#endif m">/* QOI_IMPLEMENTATION */ |