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-rw-r--r--converter/other/qoi.h471
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 */