toaruos/lib/jpeg.c
2018-12-20 21:07:35 +09:00

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/* vim: tabstop=4 shiftwidth=4 noexpandtab
* This file is part of ToaruOS and is released under the terms
* of the NCSA / University of Illinois License - see LICENSE.md
* Copyright (C) 2018 K. Lange
*
* libtoaru_jpeg: Decode simple JPEGs.
*
* Adapted from Raul Aguaviva's Python "micro JPEG visualizer":
*
* MIT License
*
* Copyright (c) 2017 Raul Aguaviva
*
* 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.
*
*/
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <toaru/graphics.h>
#include <xmmintrin.h>
#include <emmintrin.h>
#if 0
#include <toaru/trace.h>
#define TRACE_APP_NAME "jpeg"
#else
#define TRACE(...)
#endif
static sprite_t * sprite = NULL;
/* Byte swap short (because JPEG uses big-endian values) */
static void swap16(uint16_t * val) {
char * a = (char *)val;
char b = a[0];
a[0] = a[1];
a[1] = b;
}
/* JPEG compontent zig-zag ordering */
static int zigzag[] = {
0, 1, 8, 16, 9, 2, 3, 10,
17, 24, 32, 25, 18, 11, 4, 5,
12, 19, 26, 33, 40, 48, 41, 34,
27, 20, 13, 6, 7, 14, 21, 28,
35, 42, 49, 56, 57, 50, 43, 36,
29, 22, 15, 23, 30, 37, 44, 51,
58, 59, 52, 45, 38, 31, 39, 46,
53, 60, 61, 54, 47, 55, 62, 63
};
static uint8_t quant_mapping[3] = {0};
static uint8_t quant[8][64];
static int clamp(int col) {
if (col > 255) return 255;
if (col < 0) return 0;
return col;
}
/* YCbCr to RGB conversion */
static void color_conversion(
float Y, float Cb, float Cr,
int *R, int *G, int *B
) {
float r = (Cr*(2.0-2.0*0.299) + Y);
float b = (Cb*(2.0-2.0*0.114) + Y);
float g = (Y - 0.144 * b - 0.229 * r) / 0.587;
*R = clamp(r + 128);
*G = clamp(g + 128);
*B = clamp(b + 128);
}
static int xy_to_lin(int x, int y) {
return x + y * 8;
}
struct huffman_table {
uint8_t lengths[16];
uint8_t elements[256];
} huffman_tables[256] = {0};
struct stream {
FILE * file;
uint8_t byte;
int have;
int pos;
};
static void define_quant_table(FILE * f, int len) {
TRACE("Defining quant table");
while (len > 0) {
uint8_t hdr;
fread(&hdr, 1, 1, f);
fread(&quant[(hdr) & 0xF], 64, 1, f);
len -= 65;
}
TRACE("Done");
}
static void baseline_dct(FILE * f, int len) {
struct dct {
uint8_t hdr;
uint16_t height;
uint16_t width;
uint8_t components;
} __attribute__((packed)) dct;
fread(&dct, sizeof(struct dct), 1, f);
/* Read image dimensions, each as big-endian 16-bit values */
swap16(&dct.height);
swap16(&dct.width);
/* We read 7 bytes */
len -= sizeof(struct dct);
TRACE("Image dimensions are %d×%d", dct.width, dct.height);
sprite->width = dct.width;
sprite->height = dct.height;
sprite->bitmap = malloc(sizeof(uint32_t) * sprite->width * sprite->height);
sprite->masks = NULL;
sprite->alpha = 0;
sprite->blank = 0;
TRACE("Loading quantization mappings...");
for (int i = 0; i < dct.components; ++i) {
/* Quant mapping */
struct {
uint8_t id;
uint8_t samp;
uint8_t qtb_id;
} __attribute__((packed)) tmp;
fread(&tmp, sizeof(tmp), 1, f);
/* There should only be three of these for the images we support. */
if (i > 3) {
abort();
}
quant_mapping[i] = tmp.qtb_id;
/* 3 bytes were read */
len -= 3;
}
/* Skip whatever else might be in this section */
if (len > 0) {
fseek(f, len, SEEK_CUR);
}
}
static void define_huffman_table(FILE * f, int len) {
TRACE("Loading Huffman tables...");
while (len > 0) {
/* Read header ID */
uint8_t hdr;
fread(&hdr, 1, 1, f);
len--;
/* Read length table */
fread(huffman_tables[hdr].lengths, 16, 1, f);
len -= 16;
/* Read Huffman table entries */
int o = 0;
for (int i = 0; i < 16; ++i) {
int l = huffman_tables[hdr].lengths[i];
fread(&huffman_tables[hdr].elements[o], l, 1, f);
o += l;
len -= l;
}
}
/* Skip rest of section */
if (len > 0) {
fseek(f, len, SEEK_CUR);
}
}
struct idct {
float base[64];
};
/**
* norm_coeff[0] = 0.35355339059
* norm_coeff[1] = 0.5
*/
static float cosines[8][8] = {
{ 0.35355339059,0.35355339059,0.35355339059,0.35355339059,0.35355339059,0.35355339059,0.35355339059,0.35355339059 },
{ 0.490392640202,0.415734806151,0.27778511651,0.0975451610081,-0.0975451610081,-0.27778511651,-0.415734806151,-0.490392640202 },
{ 0.461939766256,0.191341716183,-0.191341716183,-0.461939766256,-0.461939766256,-0.191341716183,0.191341716183,0.461939766256 },
{ 0.415734806151,-0.0975451610081,-0.490392640202,-0.27778511651,0.27778511651,0.490392640202,0.0975451610081,-0.415734806151 },
{ 0.353553390593,-0.353553390593,-0.353553390593,0.353553390593,0.353553390593,-0.353553390593,-0.353553390593,0.353553390593 },
{ 0.27778511651,-0.490392640202,0.0975451610081,0.415734806151,-0.415734806151,-0.0975451610081,0.490392640202,-0.27778511651 },
{ 0.191341716183,-0.461939766256,0.461939766256,-0.191341716183,-0.191341716183,0.461939766256,-0.461939766256,0.191341716183 },
{ 0.0975451610081,-0.27778511651,0.415734806151,-0.490392640202,0.490392640202,-0.415734806151,0.27778511651,-0.0975451610081 },
};
static float premul[8][8][8][8]= {{{{0}}}};
static void add_idc(struct idct * self, int n, int m, int coeff) {
__m128 c = _mm_set_ps(coeff,coeff,coeff,coeff);
for (int y = 0; y < 8; ++y) {
__m128 a, b;
/* base[y][x] = base[y][x] + premul[n][m][y][x] * coeff */
/* x = 0..3 */
a = _mm_load_ps(&premul[n][m][y][0]);
a = _mm_mul_ps(a,c);
b = _mm_load_ps(&self->base[xy_to_lin(0,y)]);
a = _mm_add_ps(a,b);
_mm_store_ps(&self->base[xy_to_lin(0,y)], a);
/* x = 4..7 */
a = _mm_load_ps(&premul[n][m][y][4]);
a = _mm_mul_ps(a,c);
b = _mm_load_ps(&self->base[xy_to_lin(4,y)]);
a = _mm_add_ps(a,b);
_mm_store_ps(&self->base[xy_to_lin(4,y)], a);
}
}
static void add_zigzag(struct idct * self, int zi, int coeff) {
int i = zigzag[zi];
int n = i & 0x7;
int m = i >> 3;
add_idc(self, n, m, coeff);
}
/* Read a bit from the stream */
static int get_bit(struct stream * st) {
while ((st->pos >> 3) >= st->have) {
/* We have finished using the current byte and need to read another one */
int t = fgetc(st->file);
if (t < 0) {
/* EOF */
st->byte = 0;
} else {
st->byte = t;
}
if (st->byte == 0xFF) {
/*
* If we see 0xFF, it's followed by a 0x00
* that should be skipped.
*/
int tmp = fgetc(st->file);
if (tmp != 0) {
/*
* If it's *not*, we reached the end of the file - but
* this shouldn't happen.
*/
st->byte = 0;
}
}
/* We've seen a new byte */
st->have++;
}
/* Extract appropriate bit from this byte */
uint8_t b = st->byte;
int s = 7 - (st->pos & 0x7);
/* We move forward one position in the bit stream */
st->pos += 1;
return (b >> s) & 1;
}
/* Advance forward and get the n'th next bit */
static int get_bitn(struct stream * st, int l) {
int val = 0;
for (int i = 0; i < l; ++i) {
val = val * 2 + get_bit(st);
}
return val;
}
/*
* Read a Huffman code by reading bits and using
* the Huffman table.
*/
static int get_code(struct huffman_table * table, struct stream * st) {
int val = 0;
int off = 0;
int ini = 0;
for (int i = 0; i < 16; ++i) {
val = val * 2 + get_bit(st);
if (table->lengths[i] > 0) {
if (val - ini < table->lengths[i]) {
return table->elements[off + val - ini];
}
ini = ini + table->lengths[i];
off += table->lengths[i];
}
ini *= 2;
}
/* Invalid */
return -1;
}
/* Decode Huffman codes to values */
static int decode(int code, int bits) {
int l = 1L << (code - 1);
if (bits >= l) {
return bits;
} else {
return bits - (2 * l - 1);
}
}
/* Build IDCT matrix */
static struct idct * build_matrix(struct idct * i, struct stream * st, int idx, uint8_t * quant, int oldcoeff, int * outcoeff) {
memset(i, 0, sizeof(struct idct));
int code = get_code(&huffman_tables[idx], st);
int bits = get_bitn(st, code);
int dccoeff = decode(code, bits) + oldcoeff;
add_zigzag(i, 0, dccoeff * quant[0]);
int l = 1;
while (l < 64) {
code = get_code(&huffman_tables[16+idx], st);
if (code == 0) break;
if (code > 15) {
l += (code >> 4);
code = code & 0xF;
}
bits = get_bitn(st, code);
int coeff = decode(code, bits);
add_zigzag(i, l, coeff * quant[l]);
l += 1;
}
*outcoeff = dccoeff;
return i;
}
/* Set pixel in sprite buffer with bounds checking */
static void set_pixel(int x, int y, uint32_t color) {
if ((x < sprite->width) && (y < sprite->height)) {
SPRITE(sprite,x,y) = color;
}
}
/* Concvert YCbCr values to RGB pixels */
static void draw_matrix(int x, int y, struct idct * L, struct idct * cb, struct idct * cr) {
for (int yy = 0; yy < 8; ++yy) {
for (int xx = 0; xx < 8; ++xx) {
int o = xy_to_lin(xx,yy);
int r, g, b;
color_conversion(L->base[o], cb->base[o], cr->base[o], &r, &g, &b);
uint32_t c = 0xFF000000 | (r << 16) | (g << 8) | b;
set_pixel((x * 8 + xx), (y * 8 + yy), c);
}
}
}
static void start_of_scan(FILE * f, int len) {
TRACE("Reading image data");
/* Skip header */
fseek(f, len, SEEK_CUR);
/* Initialize bit stream */
struct stream _st = {0};
_st.file = f;
struct stream * st = &_st;
int old_lum = 0;
int old_crd = 0;
int old_cbd = 0;
for (int y = 0; y < sprite->height / 8 + !!(sprite->height & 0xf); ++y) {
TRACE("Star row %d", y );
for (int x = 0; x < sprite->width / 8 + !!(sprite->width & 0xf); ++x) {
if (y >= 134) {
TRACE("Start col %d", x);
}
/* Build matrices */
struct idct matL, matCr, matCb;
build_matrix(&matL, st, 0, quant[quant_mapping[0]], old_lum, &old_lum);
build_matrix(&matCb, st, 1, quant[quant_mapping[1]], old_cbd, &old_cbd);
build_matrix(&matCr, st, 1, quant[quant_mapping[2]], old_crd, &old_crd);
if (y >= 134) {
TRACE("Draw col %d", x);
}
draw_matrix(x, y, &matL, &matCb, &matCr);
}
}
TRACE("Done.");
}
int load_sprite_jpg(sprite_t * tsprite, char * filename) {
FILE * f = fopen(filename, "r");
if (!f) {
return 1;
}
sprite = tsprite;
memset(huffman_tables, 0, sizeof(huffman_tables));
if (premul[0][0][0][0] == 0.0) {
for (int n = 0; n < 8; ++n) {
for (int m = 0; m < 8; ++m) {
for (int y = 0; y < 8; ++y) {
for (int x = 0; x < 8; ++x) {
premul[n][m][y][x] = cosines[n][x] * cosines[m][y];
}
}
}
}
}
while (1) {
/* Read a header */
uint16_t hdr;
int r = fread(&hdr, 2, 1, f);
if (r <= 0) {
/* EOF */
break;
}
/* These headers are stored big-endian */
swap16(&hdr);
if (hdr == 0xffd8) {
/* No data */
continue;
} else if (hdr == 0xffd9) {
/* End of file */
break;
} else {
/* Regular sections with data start with a length */
uint16_t len;
fread(&len, 2, 1, f);
swap16(&len);
/* Subtract two because the length includes itself */
len -= 2;
if (hdr == 0xffdb) {
define_quant_table(f, len);
} else if (hdr == 0xffc0) {
baseline_dct(f, len);
} else if (hdr == 0xffc4) {
define_huffman_table(f, len);
} else if (hdr == 0xffda) {
start_of_scan(f, len);
/* End immediately after reading the data */
break;
} else {
TRACE("Unknown header\n");
fseek(f, len, SEEK_CUR);
}
}
}
fclose(f);
return 0;
}