diff options
Diffstat (limited to 'contrib/syslinux-4.02/com32/lib/jpeg/tinyjpeg.c')
| -rw-r--r-- | contrib/syslinux-4.02/com32/lib/jpeg/tinyjpeg.c | 1039 |
1 files changed, 1039 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/com32/lib/jpeg/tinyjpeg.c b/contrib/syslinux-4.02/com32/lib/jpeg/tinyjpeg.c new file mode 100644 index 0000000..3c6070f --- /dev/null +++ b/contrib/syslinux-4.02/com32/lib/jpeg/tinyjpeg.c @@ -0,0 +1,1039 @@ +/* + * Small jpeg decoder library + * + * Copyright (c) 2006, Luc Saillard <luc@saillard.org> + * All rights reserved. + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * - Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * + * - Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * + * - Neither the name of the author nor the names of its contributors may be + * used to endorse or promote products derived from this software without + * specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <stdint.h> +#include <errno.h> + +#include "tinyjpeg.h" +#include "tinyjpeg-internal.h" + +/* Global variable to return the last error found while deconding */ +static char error_string[256]; + +static const unsigned char zigzag[64] = +{ + 0, 1, 5, 6, 14, 15, 27, 28, + 2, 4, 7, 13, 16, 26, 29, 42, + 3, 8, 12, 17, 25, 30, 41, 43, + 9, 11, 18, 24, 31, 40, 44, 53, + 10, 19, 23, 32, 39, 45, 52, 54, + 20, 22, 33, 38, 46, 51, 55, 60, + 21, 34, 37, 47, 50, 56, 59, 61, + 35, 36, 48, 49, 57, 58, 62, 63 +}; + +/* Set up the standard Huffman tables (cf. JPEG standard section K.3) */ +/* IMPORTANT: these are only valid for 8-bit data precision! */ +static const unsigned char bits_dc_luminance[17] = +{ + 0, 0, 1, 5, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0 +}; +static const unsigned char val_dc_luminance[] = +{ + 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 +}; + +static const unsigned char bits_dc_chrominance[17] = +{ + 0, 0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0 +}; +static const unsigned char val_dc_chrominance[] = +{ + 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 +}; + +static const unsigned char bits_ac_luminance[17] = +{ + 0, 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 0x7d +}; +static const unsigned char val_ac_luminance[] = +{ + 0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12, + 0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07, + 0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08, + 0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52, 0xd1, 0xf0, + 0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16, + 0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28, + 0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, + 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, + 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, + 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, + 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, + 0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, + 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, + 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, + 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, + 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5, + 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4, + 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2, + 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, + 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, + 0xf9, 0xfa +}; + +static const unsigned char bits_ac_chrominance[17] = +{ + 0, 0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 0x77 +}; + +static const unsigned char val_ac_chrominance[] = +{ + 0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21, + 0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71, + 0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91, + 0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0, + 0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34, + 0xe1, 0x25, 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26, + 0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38, + 0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, + 0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, + 0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, + 0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, + 0x79, 0x7a, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, + 0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, + 0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, + 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, + 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, + 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, + 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, + 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, + 0xea, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, + 0xf9, 0xfa +}; + + +/* + * 4 functions to manage the stream + * + * fill_nbits: put at least nbits in the reservoir of bits. + * But convert any 0xff,0x00 into 0xff + * get_nbits: read nbits from the stream, and put it in result, + * bits is removed from the stream and the reservoir is filled + * automaticaly. The result is signed according to the number of + * bits. + * look_nbits: read nbits from the stream without marking as read. + * skip_nbits: read nbits from the stream but do not return the result. + * + * stream: current pointer in the jpeg data (read bytes per bytes) + * nbits_in_reservoir: number of bits filled into the reservoir + * reservoir: register that contains bits information. Only nbits_in_reservoir + * is valid. + * nbits_in_reservoir + * <-- 17 bits --> + * Ex: 0000 0000 1010 0000 1111 0000 <== reservoir + * ^ + * bit 1 + * To get two bits from this example + * result = (reservoir >> 15) & 3 + * + */ +#define fill_nbits(reservoir,nbits_in_reservoir,stream,nbits_wanted) do { \ + while (nbits_in_reservoir<nbits_wanted) \ + { \ + unsigned char c; \ + if (stream >= priv->stream_end) \ + longjmp(priv->jump_state, -EIO); \ + c = *stream++; \ + reservoir <<= 8; \ + if (c == 0xff && *stream == 0x00) \ + stream++; \ + reservoir |= c; \ + nbits_in_reservoir+=8; \ + } \ +} while(0); + +/* Signed version !!!! */ +#define get_nbits(reservoir,nbits_in_reservoir,stream,nbits_wanted,result) do { \ + fill_nbits(reservoir,nbits_in_reservoir,stream,(nbits_wanted)); \ + result = ((reservoir)>>(nbits_in_reservoir-(nbits_wanted))); \ + nbits_in_reservoir -= (nbits_wanted); \ + reservoir &= ((1U<<nbits_in_reservoir)-1); \ + if ((unsigned int)result < (1UL<<((nbits_wanted)-1))) \ + result += (0xFFFFFFFFUL<<(nbits_wanted))+1; \ +} while(0); + +#define look_nbits(reservoir,nbits_in_reservoir,stream,nbits_wanted,result) do { \ + fill_nbits(reservoir,nbits_in_reservoir,stream,(nbits_wanted)); \ + result = ((reservoir)>>(nbits_in_reservoir-(nbits_wanted))); \ +} while(0); + +/* To speed up the decoding, we assume that the reservoir have enough bit + * slow version: + * #define skip_nbits(reservoir,nbits_in_reservoir,stream,nbits_wanted) do { \ + * fill_nbits(reservoir,nbits_in_reservoir,stream,(nbits_wanted)); \ + * nbits_in_reservoir -= (nbits_wanted); \ + * reservoir &= ((1U<<nbits_in_reservoir)-1); \ + * } while(0); + */ +#define skip_nbits(reservoir,nbits_in_reservoir,stream,nbits_wanted) do { \ + nbits_in_reservoir -= (nbits_wanted); \ + reservoir &= ((1U<<nbits_in_reservoir)-1); \ +} while(0); + + +#define be16_to_cpu(x) (((x)[0]<<8)|(x)[1]) + +static void resync(struct jdec_private *priv); + +/** + * Get the next (valid) huffman code in the stream. + * + * To speedup the procedure, we look HUFFMAN_HASH_NBITS bits and the code is + * lower than HUFFMAN_HASH_NBITS we have automaticaly the length of the code + * and the value by using two lookup table. + * Else if the value is not found, just search (linear) into an array for each + * bits is the code is present. + * + * If the code is not present for any reason, -1 is return. + */ +static int get_next_huffman_code(struct jdec_private *priv, struct huffman_table *huffman_table) +{ + int value, hcode; + unsigned int extra_nbits, nbits; + uint16_t *slowtable; + + look_nbits(priv->reservoir, priv->nbits_in_reservoir, priv->stream, HUFFMAN_HASH_NBITS, hcode); + value = huffman_table->lookup[hcode]; + if (__likely(value >= 0)) + { + unsigned int code_size = huffman_table->code_size[value]; + skip_nbits(priv->reservoir, priv->nbits_in_reservoir, priv->stream, code_size); + return value; + } + + /* Decode more bits each time ... */ + for (extra_nbits=0; extra_nbits<16-HUFFMAN_HASH_NBITS; extra_nbits++) + { + nbits = HUFFMAN_HASH_NBITS + 1 + extra_nbits; + + look_nbits(priv->reservoir, priv->nbits_in_reservoir, priv->stream, nbits, hcode); + slowtable = huffman_table->slowtable[extra_nbits]; + /* Search if the code is in this array */ + while (slowtable[0]) { + if (slowtable[0] == hcode) { + skip_nbits(priv->reservoir, priv->nbits_in_reservoir, priv->stream, nbits); + return slowtable[1]; + } + slowtable+=2; + } + } + return 0; +} + + + + +/** + * + * Decode a single block that contains the DCT coefficients. + * The table coefficients is already dezigzaged at the end of the operation. + * + */ +void tinyjpeg_process_Huffman_data_unit(struct jdec_private *priv, int component) +{ + unsigned char j; + unsigned int huff_code; + unsigned char size_val, count_0; + + struct component *c = &priv->component_infos[component]; + short int DCT[64]; + + + /* Initialize the DCT coef table */ + memset(DCT, 0, sizeof(DCT)); + + /* DC coefficient decoding */ + huff_code = get_next_huffman_code(priv, c->DC_table); + //trace("+ %x\n", huff_code); + if (huff_code) { + get_nbits(priv->reservoir, priv->nbits_in_reservoir, priv->stream, huff_code, DCT[0]); + DCT[0] += c->previous_DC; + c->previous_DC = DCT[0]; + } else { + DCT[0] = c->previous_DC; + } + + /* AC coefficient decoding */ + j = 1; + while (j<64) + { + huff_code = get_next_huffman_code(priv, c->AC_table); + //trace("- %x\n", huff_code); + + size_val = huff_code & 0xF; + count_0 = huff_code >> 4; + + if (size_val == 0) + { /* RLE */ + if (count_0 == 0) + break; /* EOB found, go out */ + else if (count_0 == 0xF) + j += 16; /* skip 16 zeros */ + } + else + { + j += count_0; /* skip count_0 zeroes */ + if (__unlikely(j >= 64)) + { + snprintf(error_string, sizeof(error_string), "Bad huffman data (buffer overflow)"); + break; + } + get_nbits(priv->reservoir, priv->nbits_in_reservoir, priv->stream, size_val, DCT[j]); + j++; + } + } + + for (j = 0; j < 64; j++) + c->DCT[j] = DCT[zigzag[j]]; +} + +/* + * Takes two array of bits, and build the huffman table for size, and code + * + * lookup will return the symbol if the code is less or equal than HUFFMAN_HASH_NBITS. + * code_size will be used to known how many bits this symbol is encoded. + * slowtable will be used when the first lookup didn't give the result. + */ +static void build_huffman_table(const unsigned char *bits, const unsigned char *vals, struct huffman_table *table) +{ + unsigned int i, j, code, code_size, val, nbits; + unsigned char huffsize[HUFFMAN_BITS_SIZE+1], *hz; + unsigned int huffcode[HUFFMAN_BITS_SIZE+1], *hc; + int next_free_entry; + + /* + * Build a temp array + * huffsize[X] => numbers of bits to write vals[X] + */ + hz = huffsize; + for (i=1; i<=16; i++) + { + for (j=1; j<=bits[i]; j++) + *hz++ = i; + } + *hz = 0; + + memset(table->lookup, 0xff, sizeof(table->lookup)); + for (i=0; i<(16-HUFFMAN_HASH_NBITS); i++) + table->slowtable[i][0] = 0; + + /* Build a temp array + * huffcode[X] => code used to write vals[X] + */ + code = 0; + hc = huffcode; + hz = huffsize; + nbits = *hz; + while (*hz) + { + while (*hz == nbits) + { + *hc++ = code++; + hz++; + } + code <<= 1; + nbits++; + } + + /* + * Build the lookup table, and the slowtable if needed. + */ + next_free_entry = -1; + for (i=0; huffsize[i]; i++) + { + val = vals[i]; + code = huffcode[i]; + code_size = huffsize[i]; + + trace("val=%2.2x code=%8.8x codesize=%2.2d\n", val, code, code_size); + + table->code_size[val] = code_size; + if (code_size <= HUFFMAN_HASH_NBITS) + { + /* + * Good: val can be put in the lookup table, so fill all value of this + * column with value val + */ + int repeat = 1UL<<(HUFFMAN_HASH_NBITS - code_size); + code <<= HUFFMAN_HASH_NBITS - code_size; + while ( repeat-- ) + table->lookup[code++] = val; + + } + else + { + /* Perhaps sorting the array will be an optimization */ + uint16_t *slowtable = table->slowtable[code_size-HUFFMAN_HASH_NBITS-1]; + while(slowtable[0]) + slowtable+=2; + slowtable[0] = code; + slowtable[1] = val; + slowtable[2] = 0; + /* TODO: NEED TO CHECK FOR AN OVERFLOW OF THE TABLE */ + } + + } +} + +static void build_default_huffman_tables(struct jdec_private *priv) +{ + if ( (priv->flags & TINYJPEG_FLAGS_MJPEG_TABLE) + && priv->default_huffman_table_initialized) + return; + + build_huffman_table(bits_dc_luminance, val_dc_luminance, &priv->HTDC[0]); + build_huffman_table(bits_ac_luminance, val_ac_luminance, &priv->HTAC[0]); + + build_huffman_table(bits_dc_chrominance, val_dc_chrominance, &priv->HTDC[1]); + build_huffman_table(bits_ac_chrominance, val_ac_chrominance, &priv->HTAC[1]); + + priv->default_huffman_table_initialized = 1; +} + + + +/******************************************************************************* + * + * Colorspace conversion routine + * + * + * Note: + * YCbCr is defined per CCIR 601-1, except that Cb and Cr are + * normalized to the range 0..MAXJSAMPLE rather than -0.5 .. 0.5. + * The conversion equations to be implemented are therefore + * R = Y + 1.40200 * Cr + * G = Y - 0.34414 * Cb - 0.71414 * Cr + * B = Y + 1.77200 * Cb + * + ******************************************************************************/ + +static void print_SOF(const unsigned char *stream) +{ + int width, height, nr_components, precision; +#if DEBUG + const char *nr_components_to_string[] = { + "????", + "Grayscale", + "????", + "YCbCr", + "CYMK" + }; +#endif + + precision = stream[2]; + height = be16_to_cpu(stream+3); + width = be16_to_cpu(stream+5); + nr_components = stream[7]; + + trace("> SOF marker\n"); + trace("Size:%dx%d nr_components:%d (%s) precision:%d\n", + width, height, + nr_components, nr_components_to_string[nr_components], + precision); +} + +/******************************************************************************* + * + * JPEG/JFIF Parsing functions + * + * Note: only a small subset of the jpeg file format is supported. No markers, + * nor progressive stream is supported. + * + ******************************************************************************/ + +static void build_quantization_table(float *qtable, const unsigned char *ref_table) +{ + /* Taken from libjpeg. Copyright Independent JPEG Group's LLM idct. + * For float AA&N IDCT method, divisors are equal to quantization + * coefficients scaled by scalefactor[row]*scalefactor[col], where + * scalefactor[0] = 1 + * scalefactor[k] = cos(k*PI/16) * sqrt(2) for k=1..7 + * We apply a further scale factor of 8. + * What's actually stored is 1/divisor so that the inner loop can + * use a multiplication rather than a division. + */ + int i, j; + static const double aanscalefactor[8] = { + 1.0, 1.387039845, 1.306562965, 1.175875602, + 1.0, 0.785694958, 0.541196100, 0.275899379 + }; + const unsigned char *zz = zigzag; + + for (i=0; i<8; i++) { + for (j=0; j<8; j++) { + *qtable++ = ref_table[*zz++] * aanscalefactor[i] * aanscalefactor[j]; + } + } + +} + +static int parse_DQT(struct jdec_private *priv, const unsigned char *stream) +{ + int qi; + float *table; + const unsigned char *dqt_block_end; + + trace("> DQT marker\n"); + dqt_block_end = stream + be16_to_cpu(stream); + stream += 2; /* Skip length */ + + while (stream < dqt_block_end) + { + qi = *stream++; +#if SANITY_CHECK + if (qi>>4) + error("16 bits quantization table is not supported\n"); + if (qi>4) + error("No more 4 quantization table is supported (got %d)\n", qi); +#endif + table = priv->Q_tables[qi]; + build_quantization_table(table, stream); + stream += 64; + } + trace("< DQT marker\n"); + return 0; +} + +static int parse_SOF(struct jdec_private *priv, const unsigned char *stream) +{ + int i, width, height, nr_components, cid, sampling_factor; + int Q_table; + struct component *c; + + trace("> SOF marker\n"); + print_SOF(stream); + + height = be16_to_cpu(stream+3); + width = be16_to_cpu(stream+5); + nr_components = stream[7]; +#if SANITY_CHECK + if (stream[2] != 8) + error("Precision other than 8 is not supported\n"); + if (width>JPEG_MAX_WIDTH || height>JPEG_MAX_HEIGHT) + error("Width and Height (%dx%d) seems suspicious\n", width, height); + if (nr_components != 3) + error("We only support YUV images\n"); +#endif + stream += 8; + for (i=0; i<nr_components; i++) { + cid = *stream++; + sampling_factor = *stream++; + Q_table = *stream++; + c = &priv->component_infos[i]; +#if SANITY_CHECK + c->cid = cid; + if (Q_table >= COMPONENTS) + error("Bad Quantization table index (got %d, max allowed %d)\n", Q_table, COMPONENTS-1); +#endif + c->Vfactor = sampling_factor&0xf; + c->Hfactor = sampling_factor>>4; + c->Q_table = priv->Q_tables[Q_table]; + trace("Component:%d factor:%dx%d Quantization table:%d\n", + cid, c->Hfactor, c->Hfactor, Q_table ); + + } + priv->width = width; + priv->height = height; + + trace("< SOF marker\n"); + + return 0; +} + +static int parse_SOS(struct jdec_private *priv, const unsigned char *stream) +{ + unsigned int i, cid, table; + unsigned int nr_components = stream[2]; + + trace("> SOS marker\n"); + +#if SANITY_CHECK + if (nr_components != 3) + error("We only support YCbCr image\n"); +#endif + + stream += 3; + for (i=0;i<nr_components;i++) { + cid = *stream++; + table = *stream++; +#if SANITY_CHECK + if ((table&0xf)>=4) + error("We do not support more than 2 AC Huffman table\n"); + if ((table>>4)>=4) + error("We do not support more than 2 DC Huffman table\n"); + if (cid != priv->component_infos[i].cid) + error("SOS cid order (%d:%d) isn't compatible with the SOF marker (%d:%d)\n", + i, cid, i, priv->component_infos[i].cid); + trace("ComponentId:%d tableAC:%d tableDC:%d\n", cid, table&0xf, table>>4); +#endif + priv->component_infos[i].AC_table = &priv->HTAC[table&0xf]; + priv->component_infos[i].DC_table = &priv->HTDC[table>>4]; + } + priv->stream = stream+3; + trace("< SOS marker\n"); + return 0; +} + +static int parse_DHT(struct jdec_private *priv, const unsigned char *stream) +{ + unsigned int count, i; + unsigned char huff_bits[17]; + int length, index; + + length = be16_to_cpu(stream) - 2; + stream += 2; /* Skip length */ + + trace("> DHT marker (length=%d)\n", length); + + while (length>0) { + index = *stream++; + + /* We need to calculate the number of bytes 'vals' will takes */ + huff_bits[0] = 0; + count = 0; + for (i=1; i<17; i++) { + huff_bits[i] = *stream++; + count += huff_bits[i]; + } +#if SANITY_CHECK + if (count >= HUFFMAN_BITS_SIZE) + error("No more than %d bytes is allowed to describe a huffman table", HUFFMAN_BITS_SIZE); + if ( (index &0xf) >= HUFFMAN_TABLES) + error("No more than %d Huffman tables is supported (got %d)\n", HUFFMAN_TABLES, index&0xf); + trace("Huffman table %s[%d] length=%d\n", (index&0xf0)?"AC":"DC", index&0xf, count); +#endif + + if (index & 0xf0 ) + build_huffman_table(huff_bits, stream, &priv->HTAC[index&0xf]); + else + build_huffman_table(huff_bits, stream, &priv->HTDC[index&0xf]); + + length -= 1; + length -= 16; + length -= count; + stream += count; + } + trace("< DHT marker\n"); + return 0; +} + +static int parse_DRI(struct jdec_private *priv, const unsigned char *stream) +{ + unsigned int length; + + trace("> DRI marker\n"); + + length = be16_to_cpu(stream); + +#if SANITY_CHECK + if (length != 4) + error("Length of DRI marker need to be 4\n"); +#endif + + priv->restart_interval = be16_to_cpu(stream+2); + +#if DEBUG + trace("Restart interval = %d\n", priv->restart_interval); +#endif + + trace("< DRI marker\n"); + + return 0; +} + + + +static void resync(struct jdec_private *priv) +{ + int i; + + /* Init DC coefficients */ + for (i=0; i<COMPONENTS; i++) + priv->component_infos[i].previous_DC = 0; + + priv->reservoir = 0; + priv->nbits_in_reservoir = 0; + if (priv->restart_interval > 0) + priv->restarts_to_go = priv->restart_interval; + else + priv->restarts_to_go = -1; +} + +static int find_next_rst_marker(struct jdec_private *priv) +{ + int rst_marker_found = 0; + int marker; + const unsigned char *stream = priv->stream; + + /* Parse marker */ + while (!rst_marker_found) + { + while (*stream++ != 0xff) + { + if (stream >= priv->stream_end) + error("EOF while search for a RST marker."); + } + /* Skip any padding ff byte (this is normal) */ + while (*stream == 0xff) + stream++; + + marker = *stream++; + if ((RST+priv->last_rst_marker_seen) == marker) + rst_marker_found = 1; + else if (marker >= RST && marker <= RST7) + error("Wrong Reset marker found, abording"); + else if (marker == EOI) + return 0; + } + trace("RST Marker %d found at offset %d\n", priv->last_rst_marker_seen, stream - priv->stream_begin); + + priv->stream = stream; + priv->last_rst_marker_seen++; + priv->last_rst_marker_seen &= 7; + + return 0; +} + +static int parse_JFIF(struct jdec_private *priv, const unsigned char *stream) +{ + int chuck_len; + int marker; + int sos_marker_found = 0; + int dht_marker_found = 0; + const unsigned char *next_chunck; + + /* Parse marker */ + while (!sos_marker_found) + { + if (*stream++ != 0xff) + goto bogus_jpeg_format; + /* Skip any padding ff byte (this is normal) */ + while (*stream == 0xff) + stream++; + + marker = *stream++; + chuck_len = be16_to_cpu(stream); + next_chunck = stream + chuck_len; + switch (marker) + { + case SOF: + if (parse_SOF(priv, stream) < 0) + return -1; + break; + case DQT: + if (parse_DQT(priv, stream) < 0) + return -1; + break; + case SOS: + if (parse_SOS(priv, stream) < 0) + return -1; + sos_marker_found = 1; + break; + case DHT: + if (parse_DHT(priv, stream) < 0) + return -1; + dht_marker_found = 1; + break; + case DRI: + if (parse_DRI(priv, stream) < 0) + return -1; + break; + default: + trace("> Unknown marker %2.2x\n", marker); + break; + } + + stream = next_chunck; + } + + if (!dht_marker_found) { + trace("No Huffman table loaded, using the default one\n"); + build_default_huffman_tables(priv); + } + +#ifdef SANITY_CHECK + if ( (priv->component_infos[cY].Hfactor < priv->component_infos[cCb].Hfactor) + || (priv->component_infos[cY].Hfactor < priv->component_infos[cCr].Hfactor)) + error("Horizontal sampling factor for Y should be greater than horitontal sampling factor for Cb or Cr\n"); + if ( (priv->component_infos[cY].Vfactor < priv->component_infos[cCb].Vfactor) + || (priv->component_infos[cY].Vfactor < priv->component_infos[cCr].Vfactor)) + error("Vertical sampling factor for Y should be greater than vertical sampling factor for Cb or Cr\n"); + if ( (priv->component_infos[cCb].Hfactor!=1) + || (priv->component_infos[cCr].Hfactor!=1) + || (priv->component_infos[cCb].Vfactor!=1) + || (priv->component_infos[cCr].Vfactor!=1)) + error("Sampling other than 1x1 for Cr and Cb is not supported"); +#endif + + return 0; +bogus_jpeg_format: + trace("Bogus jpeg format\n"); + return -1; +} + +/******************************************************************************* + * + * Functions exported of the library. + * + * Note: Some applications can access directly to internal pointer of the + * structure. It's is not recommended, but if you have many images to + * uncompress with the same parameters, some functions can be called to speedup + * the decoding. + * + ******************************************************************************/ + +/** + * Allocate a new tinyjpeg decoder object. + * + * Before calling any other functions, an object need to be called. + */ +struct jdec_private *tinyjpeg_init(void) +{ + struct jdec_private *priv; + + priv = (struct jdec_private *)calloc(1, sizeof(struct jdec_private)); + if (priv == NULL) + return NULL; + return priv; +} + +/** + * Free a tinyjpeg object. + * + * No others function can be called after this one. + */ +void tinyjpeg_free(struct jdec_private *priv) +{ + int i; + for (i=0; i<COMPONENTS; i++) { + if (priv->components[i]) + free(priv->components[i]); + priv->components[i] = NULL; + } + free(priv); +} + +/** + * Initialize the tinyjpeg object and prepare the decoding of the stream. + * + * Check if the jpeg can be decoded with this jpeg decoder. + * Fill some table used for preprocessing. + */ +int tinyjpeg_parse_header(struct jdec_private *priv, const unsigned char *buf, unsigned int size) +{ + int ret; + + /* Identify the file */ + if ((buf[0] != 0xFF) || (buf[1] != SOI)) + error("Not a JPG file ?\n"); + + priv->stream_begin = buf+2; + priv->stream_length = size-2; + priv->stream_end = priv->stream_begin + priv->stream_length; + + ret = parse_JFIF(priv, priv->stream_begin); + + return ret; +} + +/** + * Decode and convert the jpeg image into @pixfmt@ image + * + * Note: components will be automaticaly allocated if no memory is attached. + */ +int tinyjpeg_decode(struct jdec_private *priv, + const struct tinyjpeg_colorspace *pixfmt) +{ + int x, y, sx, sy; + int xshift_by_mcu, yshift_by_mcu; + int xstride_by_mcu, ystride_by_mcu; + unsigned int bytes_per_blocklines[3], bytes_per_mcu[3]; + decode_MCU_fct decode_MCU; + const decode_MCU_fct *decode_mcu_table; + convert_colorspace_fct convert_to_pixfmt; + uint8_t *pptr[3]; + + decode_mcu_table = pixfmt->decode_mcu_table; + + /* Fix: check return value */ + pixfmt->initialize(priv, bytes_per_blocklines, bytes_per_mcu); + + xshift_by_mcu = yshift_by_mcu = 3; + if ((priv->component_infos[cY].Hfactor | priv->component_infos[cY].Vfactor) == 1) { + decode_MCU = decode_mcu_table[0]; + convert_to_pixfmt = pixfmt->convert_colorspace[0]; + trace("Use decode 1x1 sampling\n"); + } else if (priv->component_infos[cY].Hfactor == 1) { + decode_MCU = decode_mcu_table[1]; + convert_to_pixfmt = pixfmt->convert_colorspace[1]; + yshift_by_mcu = 4; + trace("Use decode 1x2 sampling (not supported)\n"); + } else if (priv->component_infos[cY].Vfactor == 2) { + decode_MCU = decode_mcu_table[3]; + convert_to_pixfmt = pixfmt->convert_colorspace[3]; + xshift_by_mcu = 4; + yshift_by_mcu = 4; + trace("Use decode 2x2 sampling\n"); + } else { + decode_MCU = decode_mcu_table[2]; + convert_to_pixfmt = pixfmt->convert_colorspace[2]; + xshift_by_mcu = 4; + trace("Use decode 2x1 sampling\n"); + } + + resync(priv); + + /* Don't forget to that block can be either 8 or 16 lines */ + bytes_per_blocklines[0] <<= yshift_by_mcu-3; + bytes_per_blocklines[1] <<= yshift_by_mcu-3; + bytes_per_blocklines[2] <<= yshift_by_mcu-3; + + bytes_per_mcu[0] <<= xshift_by_mcu-3; + bytes_per_mcu[1] <<= xshift_by_mcu-3; + bytes_per_mcu[2] <<= xshift_by_mcu-3; + + xstride_by_mcu = 1 << xshift_by_mcu; + ystride_by_mcu = 1 << yshift_by_mcu; + + pptr[0] = priv->components[0]; + pptr[1] = priv->components[1]; + pptr[2] = priv->components[2]; + + trace("bpbl = %d, bpmcu = %d\n", + bytes_per_blocklines[0], bytes_per_mcu[0]); + + for (y = priv->height; y > 0; y -= ystride_by_mcu) + { + trace("Decoding row %d\n", priv->height-y); + priv->plane[0] = pptr[0]; pptr[0] += bytes_per_blocklines[0]; + priv->plane[1] = pptr[1]; pptr[1] += bytes_per_blocklines[1]; + priv->plane[2] = pptr[2]; pptr[2] += bytes_per_blocklines[2]; + + sy = min(y, ystride_by_mcu); + + for (x = priv->width; x > 0; x -= xstride_by_mcu) + { + sx = min(x, xstride_by_mcu); + trace("Block size: %dx%d\n", sx, sy); + + decode_MCU(priv); + convert_to_pixfmt(priv, sx, sy); + priv->plane[0] += bytes_per_mcu[0]; + priv->plane[1] += bytes_per_mcu[1]; + priv->plane[2] += bytes_per_mcu[2]; + if (priv->restarts_to_go>0) + { + priv->restarts_to_go--; + if (priv->restarts_to_go == 0) + { + priv->stream -= (priv->nbits_in_reservoir/8); + resync(priv); + if (find_next_rst_marker(priv) < 0) + return -1; + } + } + } + } + + trace("Input file size: %d\n", priv->stream_length+2); + trace("Input bytes actually read: %d\n", priv->stream - priv->stream_begin + 2); + + return 0; +} + +const char *tinyjpeg_get_errorstring(struct jdec_private *priv) +{ + /* FIXME: the error string must be store in the context */ + priv = priv; + return error_string; +} + +void tinyjpeg_get_size(struct jdec_private *priv, unsigned int *width, unsigned int *height) +{ + *width = priv->width; + *height = priv->height; +} + +int tinyjpeg_get_components(struct jdec_private *priv, unsigned char **components, unsigned int ncomponents) +{ + unsigned int i; + if (ncomponents > COMPONENTS) + ncomponents = COMPONENTS; + for (i=0; i<ncomponents; i++) + components[i] = priv->components[i]; + return 0; +} + +int tinyjpeg_set_components(struct jdec_private *priv, unsigned char * const *components, unsigned int ncomponents) +{ + unsigned int i; + if (ncomponents > COMPONENTS) + ncomponents = COMPONENTS; + for (i=0; i<ncomponents; i++) + priv->components[i] = components[i]; + return 0; +} + +int tinyjpeg_get_bytes_per_row(struct jdec_private *priv, + unsigned int *bytes, + unsigned int ncomponents) +{ + unsigned int i; + if (ncomponents > COMPONENTS) + ncomponents = COMPONENTS; + for (i=0; i<ncomponents; i++) + bytes[i] = priv->bytes_per_row[i]; + return 0; +} + +int tinyjpeg_set_bytes_per_row(struct jdec_private *priv, + const unsigned int *bytes, + unsigned int ncomponents) +{ + unsigned int i; + if (ncomponents > COMPONENTS) + ncomponents = COMPONENTS; + for (i=0; i<ncomponents; i++) + priv->bytes_per_row[i] = bytes[i]; + return 0; +} + +int tinyjpeg_set_flags(struct jdec_private *priv, int flags) +{ + int oldflags = priv->flags; + priv->flags = flags; + return oldflags; +} |