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lgfx_tjpgd.c
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lgfx_tjpgd.c
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/*----------------------------------------------------------------------------/
/ TJpgDec - Tiny JPEG Decompressor R0.01c (C)ChaN, 2019
/-----------------------------------------------------------------------------/
/ The TJpgDec is a generic JPEG decompressor module for tiny embedded systems.
/ This is a free software that opened for education, research and commercial
/ developments under license policy of following terms.
/
/ Copyright (C) 2019, ChaN, all right reserved.
/
/ * The TJpgDec module is a free software and there is NO WARRANTY.
/ * No restriction on use. You can use, modify and redistribute it for
/ personal, non-profit or commercial products UNDER YOUR RESPONSIBILITY.
/ * Redistributions of source code must retain the above copyright notice.
/
/-----------------------------------------------------------------------------/
/ Oct 04, 2011 R0.01 First release.
/ Feb 19, 2012 R0.01a Fixed decompression fails when scan starts with an escape seq.
/ Sep 03, 2012 R0.01b Added JD_TBLCLIP option.
/ Mar 16, 2019 R0.01c Supprted stdint.h.
/-----------------------------------------------------------------------------/
/ original source is here : http://elm-chan.org/fsw/tjpgd/00index.html
/
/ Modified for LGFX by lovyan03, 2020
/ add support grayscale jpeg
/ add bayer pattern
/ tweak for 32bit processor
/----------------------------------------------------------------------------*/
#include "lgfx_tjpgd.h"
#include <string.h> // for memcpy memset
/*-----------------------------------------------*/
/* Zigzag-order to raster-order conversion table */
/*-----------------------------------------------*/
//#define ZIG(n) Zig[n]
static const uint8_t Zig[64] = { /* Zigzag-order to raster-order conversion table */
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
};
/*-------------------------------------------------*/
/* Input scale factor of Arai algorithm */
/* (scaled up 16 bits for fixed point operations) */
/*-------------------------------------------------*/
//#define IPSF(n) Ipsf[n]
static const uint16_t Ipsf[64] = { /* See also aa_idct.png */
(uint16_t)(1.00000*8192), (uint16_t)(1.38704*8192), (uint16_t)(1.30656*8192), (uint16_t)(1.17588*8192), (uint16_t)(1.00000*8192), (uint16_t)(0.78570*8192), (uint16_t)(0.54120*8192), (uint16_t)(0.27590*8192),
(uint16_t)(1.38704*8192), (uint16_t)(1.92388*8192), (uint16_t)(1.81226*8192), (uint16_t)(1.63099*8192), (uint16_t)(1.38704*8192), (uint16_t)(1.08979*8192), (uint16_t)(0.75066*8192), (uint16_t)(0.38268*8192),
(uint16_t)(1.30656*8192), (uint16_t)(1.81226*8192), (uint16_t)(1.70711*8192), (uint16_t)(1.53636*8192), (uint16_t)(1.30656*8192), (uint16_t)(1.02656*8192), (uint16_t)(0.70711*8192), (uint16_t)(0.36048*8192),
(uint16_t)(1.17588*8192), (uint16_t)(1.63099*8192), (uint16_t)(1.53636*8192), (uint16_t)(1.38268*8192), (uint16_t)(1.17588*8192), (uint16_t)(0.92388*8192), (uint16_t)(0.63638*8192), (uint16_t)(0.32442*8192),
(uint16_t)(1.00000*8192), (uint16_t)(1.38704*8192), (uint16_t)(1.30656*8192), (uint16_t)(1.17588*8192), (uint16_t)(1.00000*8192), (uint16_t)(0.78570*8192), (uint16_t)(0.54120*8192), (uint16_t)(0.27590*8192),
(uint16_t)(0.78570*8192), (uint16_t)(1.08979*8192), (uint16_t)(1.02656*8192), (uint16_t)(0.92388*8192), (uint16_t)(0.78570*8192), (uint16_t)(0.61732*8192), (uint16_t)(0.42522*8192), (uint16_t)(0.21677*8192),
(uint16_t)(0.54120*8192), (uint16_t)(0.75066*8192), (uint16_t)(0.70711*8192), (uint16_t)(0.63638*8192), (uint16_t)(0.54120*8192), (uint16_t)(0.42522*8192), (uint16_t)(0.29290*8192), (uint16_t)(0.14932*8192),
(uint16_t)(0.27590*8192), (uint16_t)(0.38268*8192), (uint16_t)(0.36048*8192), (uint16_t)(0.32442*8192), (uint16_t)(0.27590*8192), (uint16_t)(0.21678*8192), (uint16_t)(0.14932*8192), (uint16_t)(0.07612*8192)
};
/*---------------------------------------------*/
/* Conversion table for fast clipping process */
/*---------------------------------------------*/
#if JD_TBLCLIP
//#define BYTECLIP(v) Clip8[(uint16_t)(v) & 0x3FF]
static const uint8_t Clip8[1024] = {
/* 0..255 */
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,
96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,
128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159,
160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191,
192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223,
224, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 249, 250, 251, 252, 253, 254, 255,
/* 256..511 */
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
/* -512..-257 */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
/* -256..-1 */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};
#else /* JD_TBLCLIP */
static inline int32_t BYTECLIP (
int32_t val
)
{
if (val < 0) val = 0;
else if (val > 255) val = 255;
return val;
}
#endif
/*---------------------------------------------*/
/* Output 4x4 bayer pattern table */
/*---------------------------------------------*/
#if JD_BAYER
static const int_fast8_t Bayer[16] = { 0, 4, 1, 5,-2, 2,-1, 3, 1, 5, 0, 4,-1, 3,-2, 2};
#endif
/*-----------------------------------------------------------------------*/
/* Allocate a memory block from memory pool */
/*-----------------------------------------------------------------------*/
static uint8_t* alloc_pool ( /* Pointer to allocated memory block (NULL:no memory available) */
lgfxJdec* jd, /* Pointer to the decompressor object */
uint_fast16_t nd /* Number of bytes to allocate */
)
{
uint8_t *rp = 0;
nd = (nd + 3) & ~3; /* Align block size to the word boundary */
if (jd->sz_pool >= nd) {
jd->sz_pool -= nd;
rp = jd->pool; /* Get start of available memory pool */
jd->pool = (rp + nd); /* Allocate requierd bytes */
}
return rp; /* Return allocated memory block (NULL:no memory to allocate) */
}
/*-----------------------------------------------------------------------*/
/* Create de-quantization and prescaling tables with a DQT segment */
/*-----------------------------------------------------------------------*/
static int32_t create_qt_tbl ( /* 0:OK, !0:Failed */
lgfxJdec* jd, /* Pointer to the decompressor object */
const uint8_t* data, /* Pointer to the quantizer tables */
uint_fast16_t ndata /* Size of input data */
)
{
const uint8_t* dataend = data + ndata;
do { /* Process all tables in the segment */
size_t d = *data++; /* Get table property */
if (d & 0xF0) return JDR_FMT1; /* Err: not 8-bit resolution */
int32_t *pb = (int32_t*)alloc_pool(jd, 64 * sizeof (int32_t));/* Allocate a memory block for the table */
if (!pb) return JDR_MEM1; /* Err: not enough memory */
jd->qttbl[d & 3] = pb; /* Register the table */
for (size_t i = 0; i < 64; ++i) { /* Load the table */
uint_fast8_t z = Zig[i]; /* Zigzag-order to raster-order conversion */
pb[z] = (int32_t)((uint32_t)data[i] * Ipsf[z]); /* Apply scale factor of Arai algorithm to the de-quantizers */
}
} while (dataend != (data += 64));
return JDR_OK;
}
/*-----------------------------------------------------------------------*/
/* Create huffman code tables with a DHT segment */
/*-----------------------------------------------------------------------*/
static int32_t create_huffman_tbl ( /* 0:OK, !0:Failed */
lgfxJdec* jd, /* Pointer to the decompressor object */
const uint8_t* data, /* Pointer to the packed huffman tables */
int_fast16_t ndata /* Size of input data */
)
{
uint_fast16_t np;
uint8_t *pb, *pd;
uint16_t *ph;
do { /* Process all tables in the segment */
uint_fast8_t d = *data++; /* Get table number and class */
if (d & 0xEE) return JDR_FMT1; /* Err: invalid class/number */
uint_fast8_t cls = d >> 4; /* class = dc(0)/ac(1), table number = 0/1 */
uint_fast8_t num = d & 0x0F;
pb = alloc_pool(jd, 16); /* Allocate a memory block for the bit distribution table */
if (!pb) return JDR_MEM1; /* Err: not enough memory */
jd->huffbits[num][cls] = pb - 1;
np = 0;
size_t i = 0;
do { /* Load number of patterns for 1 to 16-bit code */
np += (pb[i] = data[i]); /* Get sum of code words for each code */
} while (++i < 16);
ph = (uint16_t*)alloc_pool(jd, np * sizeof (uint16_t));/* Allocate a memory block for the code word table */
if (!ph) return JDR_MEM1; /* Err: not enough memory */
jd->huffcode[num][cls] = ph - 1;
uint_fast16_t hc = 0;
i = 0;
do { /* Re-build huffman code word table */
size_t b = pb[i];
while (b--) *ph++ = hc++;
hc <<= 1;
} while (++i < 16);
pd = alloc_pool(jd, np); /* Allocate a memory block for the decoded data */
if (!pd) return JDR_MEM1; /* Err: not enough memory */
jd->huffdata[num][cls] = pd - 1;
memcpy(pd, data += 16, np); /* Load decoded data corresponds to each code ward */
data += np;
} while (ndata -= 17 + np);
return JDR_OK;
}
/*-----------------------------------------------------------------------*/
/* Extract N bits from input stream */
/*-----------------------------------------------------------------------*/
static int32_t bitext ( /* >=0: extracted data, <0: error code */
lgfxJdec* jd, /* Pointer to the decompressor object */
uint_fast8_t nbit /* Number of bits to extract (1 to 11) */
)
{
uint8_t *dp;
uint_fast8_t msk;
uint32_t v;
msk = jd->dmsk; dp = jd->dptr;
v = 0;
for (;;) {
if (!msk) { /* Next byte? */
uint8_t *dpend = jd->dpend;
if (++dp == dpend) { /* No input data is available, re-fill input buffer */
dp = jd->inbuf; /* Top of input buffer */
jd->dpend = dpend = dp + jd->infunc(jd->device, dp, JD_SZBUF);
if (dp == dpend) return 0 - (int32_t)JDR_INP; /* Err: read error or wrong stream termination */
}
if (*dp == 0xff) { /* Is start of flag sequence? */
if (++dp == dpend) { /* No input data is available, re-fill input buffer */
dp = jd->inbuf; /* Top of input buffer */
jd->dpend = dpend = dp + jd->infunc(jd->device, dp, JD_SZBUF);
if (dp == dpend) return 0 - (int32_t)JDR_INP; /* Err: read error or wrong stream termination */
}
if (*dp != 0) return 0 - (int32_t)JDR_FMT1; /* Err: unexpected flag is detected (may be collapted data) */
*dp = 0xff; /* The flag is a data 0xFF */
}
msk = 8; /* Read from MSB */
}
uint_fast8_t s = *dp; /* Get next data byte */
if (msk >= nbit) {
msk -= nbit;
jd->dmsk = msk; jd->dptr = dp;
return v + ((s >> msk) & ((1 << nbit) - 1)); /* Get bits */
}
nbit -= msk;
v += (s & ((1 << msk) - 1)) << nbit; /* Get bits */
msk = 0;
}
}
/*-----------------------------------------------------------------------*/
/* Extract a huffman decoded data from input stream */
/*-----------------------------------------------------------------------*/
static int32_t huffext ( /* >=0: decoded data, <0: error code */
lgfxJdec* jd, /* Pointer to the decompressor object */
const uint8_t* hbits, /* Pointer to the bit distribution table */
const uint16_t* hcode, /* Pointer to the code word table */
const uint8_t* hdata /* Pointer to the data table */
)
{
uint8_t *dp;
uint_fast8_t msk, bl;
uint32_t v;
msk = jd->dmsk; dp = jd->dptr;
v = 0;
bl = 16; /* Max code length */
for (;;) {
if (!msk) { /* Next byte? */
uint8_t *dpend = jd->dpend;
if (++dp == dpend) { /* No input data is available, re-fill input buffer */
dp = jd->inbuf; /* Top of input buffer */
jd->dpend = dpend = dp + jd->infunc(jd->device, dp, JD_SZBUF);
if (dp == dpend) return 0 - (int32_t)JDR_INP; /* Err: read error or wrong stream termination */
}
if (*dp == 0xff) { /* Is start of flag sequence? */
if (++dp == dpend) { /* No input data is available, re-fill input buffer */
dp = jd->inbuf; /* Top of input buffer */
jd->dpend = dpend = dp + jd->infunc(jd->device, dp, JD_SZBUF);
if (dp == dpend) return 0 - (int32_t)JDR_INP; /* Err: read error or wrong stream termination */
}
if (*dp != 0) return 0 - (int32_t)JDR_FMT1; /* Err: unexpected flag is detected (may be collapted data) */
*dp = 0xff; /* The flag is a data 0xFF */
}
msk = 8; /* Read from MSB */
}
uint_fast8_t s = *dp; /* Get next data byte */
do {
v = (v << 1) + ((s >> (--msk)) & 1); /* Get a bit */
size_t nd = *++hbits;
if (nd) {
do { /* Search the code word in this bit length */
++hdata;
if (v == *++hcode) goto huffext_match; /* Matched? */
} while (--nd);
}
if (!--bl) return 0 - (int32_t)JDR_FMT1; /* Err: code not found (may be collapted data) */
} while (msk);
}
huffext_match:
jd->dmsk = msk;
jd->dptr = dp;
return *hdata; /* Return the decoded data */
}
/*-----------------------------------------------------------------------*/
/* Apply Inverse-DCT in Arai Algorithm (see also aa_idct.png) */
/*-----------------------------------------------------------------------*/
static void block_idct (
int32_t* src, /* Input block data (de-quantized and pre-scaled for Arai Algorithm) */
uint8_t* dst /* Pointer to the destination to store the block as byte array */
)
{
const int32_t M13 = (int32_t)(1.41421*256), M2 = (int32_t)(1.08239*256), M4 = (int32_t)(2.61313*256), M5 = (int32_t)(1.84776*256);
int32_t v0, v1, v2, v3, v4, v5, v6, v7;
int32_t t10, t11, t12, t13;
/* Process columns */
for (int i = 0; i < 8; ++i) {
/* Get and Process the odd elements */
v4 = src[8 * 7];
v5 = src[8 * 1];
v6 = src[8 * 5];
v7 = src[8 * 3];
t10 = v5 - v4;
t11 = v5 + v4;
t12 = v6 - v7;
v7 += v6;
v5 = (t11 - v7) * M13 >> 8;
t13 = (t10 + t12) * M5 >> 8;
v6 = t13 - ((t12 * M4 >> 8) + (v7 += t11));
v4 = t13 - ((t10 * M2 >> 8) + (v5 -= v6));
/* Get and Process the even elements */
v0 = src[8 * 0];
v2 = src[8 * 4];
t10 = v0 + v2;
t12 = v0 - v2;
v1 = src[8 * 2];
v3 = src[8 * 6];
t11 = (v1 - v3) * M13 >> 8;
v3 += v1;
t11 -= v3;
v0 = t10 + v3;
v3 = t10 - v3;
v1 = t12 + t11;
v2 = t12 - t11;
/* Write-back transformed values */
src[8 * 0] = v0 + v7;
src[8 * 7] = v0 - v7;
src[8 * 1] = v1 + v6;
src[8 * 6] = v1 - v6;
src[8 * 2] = v2 + v5;
src[8 * 5] = v2 - v5;
src[8 * 3] = v3 + v4;
src[8 * 4] = v3 - v4;
++src; /* Next column */
}
/* Process rows */
src -= 8;
for (int i = 0; i < 8; ++i) {
/* Get and Process the odd elements */
v4 = src[1];
v5 = src[7] + v4;
v4 = (v4 << 1) - v5;
v6 = src[5];
v7 = src[3] + v6;
v6 = (v6 << 1) - v7;
v7 += v5;
v5 = (v5 << 1) - v7;
t13 = v4 + v6;
t13 = t13 * M5 >> 8;
v6 = v6 * M4 >> 8;
v6 += v7;
v6 = t13 - v6;
v5 = v5 * M13 >> 8;
v5 -= v6;
v4 = v4 * M2 >> 8;
v4 += v5;
v4 = t13 - v4;
/* Get and Process the even elements */
v0 = src[0] + (128L << 8); /* remove DC offset (-128) here */
v2 = src[4];
t10 = v0 + v2;
t12 = v0 - v2;
v1 = src[2];
v3 = src[6] + v1;
t11 = (v1 << 1) - v3;
t11 = t11 * M13 >> 8;
t11 -= v3;
v0 = t10 + v3;
v3 = t10 - v3;
v1 = t12 + t11;
v2 = t12 - t11;
/* Descale the transformed values 8 bits and output */
#if defined (ESP32) || defined (CONFIG_IDF_TARGET_ESP32) || defined (CONFIG_IDF_TARGET_ESP32S2) || defined (ESP_PLATFORM)
int32_t d0 = (v0 + v7) >> 8;
int32_t d7 = (v0 - v7) >> 8;
int32_t d1 = (v1 + v6) >> 8;
int32_t d6 = (v1 - v6) >> 8;
int32_t d2 = (v2 + v5) >> 8;
int32_t d5 = (v2 - v5) >> 8;
int32_t d3 = (v3 + v4) >> 8;
int32_t d4 = (v3 - v4) >> 8;
if (d0 < 0) d0 = 0; else if (d0 > 255) d0 = 255;
if (d1 < 0) d1 = 0; else if (d1 > 255) d1 = 255;
if (d2 < 0) d2 = 0; else if (d2 > 255) d2 = 255;
if (d3 < 0) d3 = 0; else if (d3 > 255) d3 = 255;
if (d4 < 0) d4 = 0; else if (d4 > 255) d4 = 255;
if (d5 < 0) d5 = 0; else if (d5 > 255) d5 = 255;
if (d6 < 0) d6 = 0; else if (d6 > 255) d6 = 255;
if (d7 < 0) d7 = 0; else if (d7 > 255) d7 = 255;
dst[0] = d0;
dst[1] = d1;
dst[2] = d2;
dst[3] = d3;
dst[4] = d4;
dst[5] = d5;
dst[6] = d6;
dst[7] = d7;
#else
dst[0] = BYTECLIP((v0 + v7) >> 8);
dst[7] = BYTECLIP((v0 - v7) >> 8);
dst[1] = BYTECLIP((v1 + v6) >> 8);
dst[6] = BYTECLIP((v1 - v6) >> 8);
dst[2] = BYTECLIP((v2 + v5) >> 8);
dst[5] = BYTECLIP((v2 - v5) >> 8);
dst[3] = BYTECLIP((v3 + v4) >> 8);
dst[4] = BYTECLIP((v3 - v4) >> 8);
#endif
dst += 8;
src += 8; /* Next row */
}
}
/*-----------------------------------------------------------------------*/
/* Load all blocks in the MCU into working buffer */
/*-----------------------------------------------------------------------*/
static JRESULT mcu_load (
lgfxJdec* jd /* Pointer to the decompressor object */
)
{
int32_t *tmp = (int32_t*)jd->workbuf; /* Block working buffer for de-quantize and IDCT */
int32_t b, d, e;
uint32_t blk, nby, nbc;
uint8_t *bp;
const uint8_t *hb, *hd;
const uint16_t *hc;
nby = jd->msx * jd->msy; /* Number of Y blocks (1, 2 or 4) */
nbc = jd->comps_in_frame - 1; /* Number of C blocks (2 or 0(grayscale)) */
bp = jd->mcubuf; /* Pointer to the first block */
for (blk = 0; blk < nby + nbc; ++blk) {
size_t cmp = (blk < nby) ? 0 : blk - nby + 1; /* Component number 0:Y, 1:Cb, 2:Cr */
size_t id = cmp ? 1 : 0; /* Huffman table ID of the component */
/* Extract a DC element from input stream */
hb = jd->huffbits[id][0]; /* Huffman table for the DC element */
hc = jd->huffcode[id][0];
hd = jd->huffdata[id][0];
b = huffext(jd, hb, hc, hd); /* Extract a huffman coded data (bit length) */
if (b < 0) return (JRESULT)(-b); /* Err: invalid code or input */
d = jd->dcv[cmp]; /* DC value of previous block */
if (b) { /* If there is any difference from previous block */
e = bitext(jd, b); /* Extract data bits */
if (e < 0) return (JRESULT)(-e); /* Err: input */
b = 1 << (b - 1); /* MSB position */
if (!(e & b)) e -= (b << 1) - 1; /* Restore sign if needed */
d += e; /* Get current value */
jd->dcv[cmp] = d; /* Save current DC value for next block */
}
const int32_t *dqf = jd->qttbl[jd->qtid[cmp]]; /* De-quantizer table ID for this component */
tmp[0] = d * dqf[0] >> 8; /* De-quantize, apply scale factor of Arai algorithm and descale 8 bits */
/* Extract following 63 AC elements from input stream */
memset(&tmp[1], 0, 63*sizeof(int32_t)); /* Clear rest of elements */
hb = jd->huffbits[id][1]; /* Huffman table for the AC elements */
hc = jd->huffcode[id][1];
hd = jd->huffdata[id][1];
uint_fast8_t i = 1; /* Top of the AC elements */
do {
b = huffext(jd, hb, hc, hd); /* Extract a huffman coded value (zero runs and bit length) */
if (b == 0) break; /* EOB? */
if (b < 0) return (JRESULT)(-b); /* Err: invalid code or input error */
i += b >> 4; /* Number of leading zero elements Skip zero elements */
if (b &= 0x0F) { /* Bit length */
d = bitext(jd, b); /* Extract data bits */
if (d < 0) return (JRESULT)(-d);/* Err: input device */
b = 1 << (b - 1); /* MSB position */
if (!(d & b)) d -= (b << 1) - 1;/* Restore negative value if needed */
uint_fast8_t z = Zig[i]; /* Zigzag-order to raster-order converted index */
tmp[z] = d * dqf[z] >> 8; /* De-quantize, apply scale factor of Arai algorithm and descale 8 bits */
}
} while (++i < 64); /* Next AC element */
if (JD_USE_SCALE && jd->scale == 3) {
*bp = (uint8_t)((*tmp >> 8) + 128); /* If scale ratio is 1/8, IDCT can be ommited and only DC element is used */
} else {
block_idct(tmp, bp); /* Apply IDCT and store the block to the MCU buffer */
}
bp += 64; /* Next block */
}
return JDR_OK; /* All blocks have been loaded successfully */
}
/*-----------------------------------------------------------------------*/
/* Output an MCU: Convert YCrCb to RGB and output it in RGB form */
/*-----------------------------------------------------------------------*/
static JRESULT mcu_output (
lgfxJdec* jd, /* Pointer to the decompressor object */
uint32_t (*outfunc)(void*, void*, JRECT*), /* RGB output function */
uint32_t x, /* MCU position in the image (left of the MCU) */
uint32_t y /* MCU position in the image (top of the MCU) */
)
{
const int_fast16_t FP_SHIFT = 8;
uint32_t ix, iy, mx, my, rx, ry;
int32_t yy, cb, cr;
uint8_t *py, *pc, *rgb24;
JRECT rect;
mx = jd->msx << 3; my = jd->msy << 3; /* MCU size (pixel) */
rx = (mx < jd->width - x) ? mx : jd->width - x; /* Output rectangular size (it may be clipped at right/bottom end) */
ry = (my < jd->height - y) ? my : jd->height - y;
if (JD_USE_SCALE) {
rx >>= jd->scale; ry >>= jd->scale;
if (!rx || !ry) return JDR_OK; /* Skip this MCU if all pixel is to be rounded off */
x >>= jd->scale; y >>= jd->scale;
}
rect.left = x; rect.right = x + rx - 1; /* Rectangular area in the frame buffer */
rect.top = y; rect.bottom = y + ry - 1;
uint8_t* workbuf = (uint8_t*)jd->workbuf;
if (!JD_USE_SCALE || jd->scale != 3) { /* Not for 1/8 scaling */
uint_fast8_t ixshift = (mx == 16);
uint_fast8_t iyshift = (my == 16);
/* Build an RGB MCU from discrete comopnents */
rgb24 = workbuf;
iy = 0;
do {
#if JD_BAYER
const int_fast8_t* btbl = &Bayer[(iy & 3) << 2];
#endif
py = &jd->mcubuf[((iy & 8) + iy) << 3];
pc = &jd->mcubuf[((mx << iyshift) + (iy >> iyshift)) << 3];
ix = 0;
do {
do {
cb = (pc[ 0] - 128); /* Get Cb/Cr component and restore right level */
cr = (pc[64] - 128);
++pc;
/* Convert CbCr to RGB */
uint_fast16_t rr = ((int32_t)(1.402 * (1<<FP_SHIFT)) * cr) >> FP_SHIFT;
uint_fast16_t gg = ((int32_t)(0.34414 * (1<<FP_SHIFT)) * cb
+ (int32_t)(0.71414 * (1<<FP_SHIFT)) * cr) >> FP_SHIFT;
uint_fast16_t bb = ((int32_t)(1.772 * (1<<FP_SHIFT)) * cb) >> FP_SHIFT;
do {
#if JD_BAYER
yy = *py + btbl[ix & 3]; /* Get Y component */
#else
yy = *py; /* Get Y component */
#endif
++py;
/* Convert YCbCr to RGB */
rgb24[0] = BYTECLIP(yy + rr);
rgb24[1] = BYTECLIP(yy - gg);
rgb24[2] = BYTECLIP(yy + bb);
rgb24 += 3;
} while (++ix & ixshift);
} while (ix & 7);
py += 64 - 8; /* Jump to next block if double block heigt */
} while (ix != mx);
} while (++iy < my);
/* Descale the MCU rectangular if needed */
if (JD_USE_SCALE && jd->scale) {
uint32_t x, y, r, g, b, s, w;
uint8_t *op;
/* Get averaged RGB value of each square correcponds to a pixel */
s = jd->scale * 2; /* Bumber of shifts for averaging */
w = 1 << jd->scale; /* Width of square */
op = workbuf;
iy = 0;
do {
ix = 0;
do {
rgb24 = &workbuf[(iy * mx + ix) * 3];
r = g = b = 0;
y = 0;
do { /* Accumulate RGB value in the square */
x = 0;
do {
r += rgb24[x*3 ];
g += rgb24[x*3+1];
b += rgb24[x*3+2];
} while (++x < w);
rgb24 += mx * 3;
} while (++y < w);
/* Put the averaged RGB value as a pixel */
op[0] = r >> s;
op[1] = g >> s;
op[2] = b >> s;
op += 3;
} while ((ix += w) < mx);
} while ((iy += w) < my);
}
} else { /* For only 1/8 scaling (left-top pixel in each block are the DC value of the block) */
/* Build a 1/8 descaled RGB MCU from discrete comopnents */
rgb24 = workbuf;
pc = jd->mcubuf + mx * my;
cb = pc[0] - 128; /* Get Cb/Cr component and restore right level */
cr = pc[64] - 128;
iy = 0;
do {
py = jd->mcubuf;
if (iy == 8) py += 64 * 2;
ix = 0;
do {
yy = *py; /* Get Y component */
py += 64;
/* Convert YCbCr to RGB */
rgb24[0] = BYTECLIP(yy + (((int32_t)(1.402 * (1<<FP_SHIFT)) * cr) >> FP_SHIFT));
rgb24[1] = BYTECLIP(yy - (((int32_t)(0.34414 * (1<<FP_SHIFT)) * cb
+ (int32_t)(0.71414 * (1<<FP_SHIFT)) * cr) >> FP_SHIFT));
rgb24[2] = BYTECLIP(yy + (((int32_t)(1.772 * (1<<FP_SHIFT)) * cb) >> FP_SHIFT));
rgb24 += 3;
} while ((ix += 8) < mx);
} while ((iy += 8) < my);
}
/* Squeeze up pixel table if a part of MCU is to be truncated */
mx >>= jd->scale;
if (rx < mx) {
uint8_t *s, *d;
s = d = workbuf;
for (size_t y = 1; y < ry; ++y) {
memcpy(d += rx * 3, s += mx * 3, rx * 3); /* Copy effective pixels */
}
}
/* Convert RGB888 to RGB565 if needed */
if (JD_FORMAT == 1) {
uint8_t *s = workbuf;
uint16_t *d = (uint16_t*)s;
uint_fast16_t w;
uint_fast16_t n = rx * ry;
do {
w = (*s++ & 0xF8) << 8; /* RRRRR----------- */
w |= (*s++ & 0xFC) << 3; /* -----GGGGGG----- */
w |= *s++ >> 3; /* -----------BBBBB */
*d++ = w;
} while (--n);
}
/* Output the RGB rectangular */
return outfunc(jd->device, workbuf, &rect) ? JDR_OK : JDR_INTR;
}
/*-----------------------------------------------------------------------*/
/* Process restart interval */
/*-----------------------------------------------------------------------*/
static JRESULT restart (
lgfxJdec* jd, /* Pointer to the decompressor object */
uint16_t rstn /* Expected restert sequense number */
)
{
uint16_t d;
uint8_t *dp = jd->dptr, *dpend = jd->dpend;
/* Discard padding bits and get two bytes from the input stream */
d = 0;
for (int i = 0; i < 2; ++i) {
if (++dp == dpend) { /* No input data is available, re-fill input buffer */
dp = jd->inbuf;
jd->dpend = dpend = dp + jd->infunc(jd->device, dp, JD_SZBUF);
if (dp == dpend) return JDR_INP;
}
d = (d << 8) | *dp; /* Get a byte */
}
jd->dptr = dp; jd->dmsk = 0;
/* Check the marker */
if ((d & 0xFFD8) != 0xFFD0 || (d & 7) != (rstn & 7)) {
return JDR_FMT1; /* Err: expected RSTn marker is not detected (may be collapted data) */
}
/* Reset DC offset */
jd->dcv[2] = jd->dcv[1] = jd->dcv[0] = 0;
return JDR_OK;
}
/*-----------------------------------------------------------------------*/
/* Analyze the JPEG image and Initialize decompressor object */
/*-----------------------------------------------------------------------*/
//#define LDB_WORD(ptr) (uint16_t)(((uint16_t)*((uint8_t*)(ptr))<<8)|(uint16_t)*(uint8_t*)((ptr)+1))
static inline uint16_t LDB_WORD(uint8_t* ptr) {
return ptr[0]<<8 | ptr[1];
}
JRESULT lgfx_jd_prepare (
lgfxJdec* jd, /* Blank decompressor object */
uint32_t (*infunc)(void*, uint8_t*, uint32_t), /* JPEG strem input function */
void* pool, /* Working buffer for the decompression session */
uint_fast16_t sz_pool, /* Size of working buffer */
void* dev /* I/O device identifier for the session */
)
{
uint8_t *seg;
uint32_t ofs;
size_t n;
int32_t rc;
if (!pool) return JDR_PAR;
jd->pool = (uint8_t*)pool; /* Work memroy */
jd->sz_pool = sz_pool; /* Size of given work memory */
jd->infunc = infunc; /* Stream input function */
jd->device = dev; /* I/O device identifier */
jd->nrst = 0; /* No restart interval (default) */
// memset(jd->huffbits, 0, sizeof(uint8_t*) * 4); /* Nulls pointers */
// memset(jd->huffcode, 0, sizeof(uint16_t*) * 4);
// memset(jd->huffdata, 0, sizeof(uint8_t*) * 4);
// memset(jd->qttbl, 0, sizeof(uint32_t*) * 4);
jd->inbuf = seg = alloc_pool(jd, JD_SZBUF); /* Allocate stream input buffer */
if (!seg) return JDR_MEM1;
if (infunc(dev, seg, 2) != 2) return JDR_INP;/* Check SOI marker */
if (LDB_WORD(seg) != 0xFFD8) return JDR_FMT1; /* Err: SOI is not detected */
ofs = 2;
for (;;) {
if (infunc(dev, seg, 1) != 1) return JDR_INP;
if (seg[0] != 0xFF) return JDR_FMT1; /* Check a JPEG marker */
do
{
if (infunc(dev, &seg[1], 1) != 1) return JDR_INP;
} while (seg[1] == 0xFF);
if (infunc(dev, &seg[2], 2) != 2) return JDR_INP;
uint_fast16_t len = LDB_WORD(seg + 2) - 2; /* Length field */
ofs += 4 + len; /* Number of bytes loaded */
switch (seg[1]) { /* Marker */
case 0xC0: /* SOF0 (baseline JPEG) */
/* Load segment data */
if (len > JD_SZBUF) return JDR_MEM2;
if (infunc(dev, seg, len) != len) return JDR_INP;
jd->width = LDB_WORD(seg+3); /* Image width in unit of pixel */
jd->height = LDB_WORD(seg+1); /* Image height in unit of pixel */
jd->comps_in_frame = seg[5];
if (seg[5] != 1 && seg[5] != 3)
return JDR_FMT3; /* Err: Supports only Y/Cb/Cr or Y(Grayscale) format */
/* Check three image components */
for (size_t i = 0; i < seg[5]; ++i) {
uint_fast8_t b = seg[7 + 3 * i]; /* Get sampling factor */
if (!i) { /* Y component */
if (b != 0x11 && b != 0x22 && b != 0x21) { /* Check sampling factor */
return JDR_FMT3; /* Err: Supports only 4:4:4, 4:2:0 or 4:2:2 */
}
jd->msx = b >> 4; jd->msy = b & 15; /* Size of MCU [blocks] */
} else { /* Cb/Cr component */
if (b != 0x11) return JDR_FMT3; /* Err: Sampling factor of Cr/Cb must be 1 */
}
b = seg[8 + 3 * i]; /* Get dequantizer table ID for this component */
if (b > 3) return JDR_FMT3; /* Err: Invalid ID */
jd->qtid[i] = b;
}
break;
case 0xDD: /* DRI */
/* Load segment data */
if (len > JD_SZBUF) return JDR_MEM2;
if (infunc(dev, seg, len) != len) return JDR_INP;
/* Get restart interval (MCUs) */
jd->nrst = LDB_WORD(seg);
break;
case 0xC4: /* DHT */
/* Load segment data */
if (len > JD_SZBUF) return JDR_MEM2;
if (infunc(dev, seg, len) != len) return JDR_INP;
/* Create huffman tables */
rc = create_huffman_tbl(jd, seg, len);
if (rc) return (JRESULT)rc;
break;
case 0xDB: /* DQT */
/* Load segment data */
if (len > JD_SZBUF) return JDR_MEM2;
if (infunc(dev, seg, len) != len) return JDR_INP;
/* Create de-quantizer tables */
rc = create_qt_tbl(jd, seg, len);
if (rc) return (JRESULT)rc;
break;
case 0xDA: /* SOS */
/* Load segment data */
if (len > JD_SZBUF) return JDR_MEM2;
if (infunc(dev, seg, len) != len) return JDR_INP;
if (!jd->width || !jd->height) return JDR_FMT1; /* Err: Invalid image size */
if (seg[0] != jd->comps_in_frame) return JDR_FMT3; /* Err: Supports only three color or grayscale components format */
/* Check if all tables corresponding to each components have been loaded */
for (size_t i = 0; i < jd->comps_in_frame; ++i) {
uint_fast8_t b = seg[2 + 2 * i]; /* Get huffman table ID */
if (b != 0x00 && b != 0x11) return JDR_FMT3; /* Err: Different table number for DC/AC element */
b = i ? 1 : 0;
if (!jd->huffbits[b][0] || !jd->huffbits[b][1]) { /* Check dc/ac huffman table for this component */
return JDR_FMT1; /* Err: Nnot loaded */
}
if (!jd->qttbl[jd->qtid[i]]) { /* Check dequantizer table for this component */
return JDR_FMT1; /* Err: Not loaded */
}
}
/* Allocate working buffer for MCU and RGB */
n = jd->msy * jd->msx; /* Number of Y blocks in the MCU */
if (!n) return JDR_FMT1; /* Err: SOF0 has not been loaded */
len = n * 64 * 2 + 64; /* Allocate buffer for IDCT and RGB output */
if (len < 256) len = 256; /* but at least 256 byte is required for IDCT */
jd->workbuf = alloc_pool(jd, len); /* and it may occupy a part of following MCU working buffer for RGB output */
if (!jd->workbuf) return JDR_MEM1; /* Err: not enough memory */
jd->mcubuf = (uint8_t*)alloc_pool(jd, (n + 2) * 64); /* Allocate MCU working buffer */
if (!jd->mcubuf) return JDR_MEM1; /* Err: not enough memory */
if (jd->comps_in_frame == 1) {
memset(&jd->mcubuf[64], 128, 128); /* Cb/Cr clear ( for grayscale )*/
}
/* Pre-load the JPEG data to extract it from the bit stream */
ofs %= JD_SZBUF; /* Align read offset to JD_SZBUF */
int32_t dc = infunc(dev, seg + ofs, JD_SZBUF - ofs);
jd->dptr = seg + ofs - 1;
jd->dpend = seg + ofs + dc;
jd->dmsk = 0; /* Prepare to read bit stream */
return JDR_OK; /* Initialization succeeded. Ready to decompress the JPEG image. */
case 0xC1: /* SOF1 */
case 0xC2: /* SOF2 */
case 0xC3: /* SOF3 */
case 0xC5: /* SOF5 */
case 0xC6: /* SOF6 */
case 0xC7: /* SOF7 */
case 0xC9: /* SOF9 */
case 0xCA: /* SOF10 */
case 0xCB: /* SOF11 */
case 0xCD: /* SOF13 */
case 0xCE: /* SOF14 */
case 0xCF: /* SOF15 */
case 0xD9: /* EOI */
return JDR_FMT3; /* Unsuppoted JPEG standard (may be progressive JPEG) */
default: /* Unknown segment (comment, exif or etc..) */
/* Skip segment data */
if (infunc(dev, 0, len) != len) { /* Null pointer specifies to skip bytes of stream */
return JDR_INP;
}
}
}
}
/*-----------------------------------------------------------------------*/
/* Start to decompress the JPEG picture */
/*-----------------------------------------------------------------------*/
JRESULT lgfx_jd_decomp (
lgfxJdec* jd, /* Initialized decompression object */
uint32_t (*outfunc)(void*, void*, JRECT*), /* RGB output function */
uint_fast8_t scale /* Output de-scaling factor (0 to 3) */
)
{
uint32_t x, y, mx, my;
uint32_t nrst, rst, rsc;
JRESULT rc;
if (scale > (JD_USE_SCALE ? 3 : 0)) return JDR_PAR;
jd->scale = scale;
nrst = jd->nrst;
mx = jd->msx << 3; my = jd->msy << 3; /* Size of the MCU (pixel) */
jd->dcv[2] = jd->dcv[1] = jd->dcv[0] = 0; /* Initialize DC values */
rst = rsc = 0;
rc = JDR_OK;
for (y = 0; y < jd->height; y += my) { /* Vertical loop of MCUs */
x = 0;
do { /* Horizontal loop of MCUs */
if (nrst && rst++ == nrst) { /* Process restart interval if enabled */