19f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project/* 29f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * jdhuff.h 39f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * 49f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * Copyright (C) 1991-1997, Thomas G. Lane. 59f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * This file is part of the Independent JPEG Group's software. 69f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * For conditions of distribution and use, see the accompanying README file. 79f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * 89f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * This file contains declarations for Huffman entropy decoding routines 99f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * that are shared between the sequential decoder (jdhuff.c) and the 109f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * progressive decoder (jdphuff.c). No other modules need to see these. 119f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project */ 129f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 139f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project/* Short forms of external names for systems with brain-damaged linkers. */ 149f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 159f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project#ifdef NEED_SHORT_EXTERNAL_NAMES 169f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project#define jpeg_make_d_derived_tbl jMkDDerived 179f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project#define jpeg_fill_bit_buffer jFilBitBuf 189f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project#define jpeg_huff_decode jHufDecode 199f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project#endif /* NEED_SHORT_EXTERNAL_NAMES */ 209f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 219f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 229f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project/* Derived data constructed for each Huffman table */ 239f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 249f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project#define HUFF_LOOKAHEAD 8 /* # of bits of lookahead */ 259f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 269f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Projecttypedef struct { 279f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project /* Basic tables: (element [0] of each array is unused) */ 289f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project INT32 maxcode[18]; /* largest code of length k (-1 if none) */ 299f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project /* (maxcode[17] is a sentinel to ensure jpeg_huff_decode terminates) */ 309f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project INT32 valoffset[17]; /* huffval[] offset for codes of length k */ 319f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project /* valoffset[k] = huffval[] index of 1st symbol of code length k, less 329f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * the smallest code of length k; so given a code of length k, the 339f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * corresponding symbol is huffval[code + valoffset[k]] 349f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project */ 359f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 369f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project /* Link to public Huffman table (needed only in jpeg_huff_decode) */ 379f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project JHUFF_TBL *pub; 389f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 399f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project /* Lookahead tables: indexed by the next HUFF_LOOKAHEAD bits of 409f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * the input data stream. If the next Huffman code is no more 419f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * than HUFF_LOOKAHEAD bits long, we can obtain its length and 429f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * the corresponding symbol directly from these tables. 439f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project */ 449f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project int look_nbits[1<<HUFF_LOOKAHEAD]; /* # bits, or 0 if too long */ 459f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project UINT8 look_sym[1<<HUFF_LOOKAHEAD]; /* symbol, or unused */ 469f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project} d_derived_tbl; 479f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 489f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project/* Expand a Huffman table definition into the derived format */ 499f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source ProjectEXTERN(void) jpeg_make_d_derived_tbl 509f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project JPP((j_decompress_ptr cinfo, boolean isDC, int tblno, 519f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project d_derived_tbl ** pdtbl)); 529f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 539f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 549f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project/* 559f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * Fetching the next N bits from the input stream is a time-critical operation 569f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * for the Huffman decoders. We implement it with a combination of inline 579f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * macros and out-of-line subroutines. Note that N (the number of bits 589f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * demanded at one time) never exceeds 15 for JPEG use. 599f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * 609f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * We read source bytes into get_buffer and dole out bits as needed. 619f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * If get_buffer already contains enough bits, they are fetched in-line 629f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * by the macros CHECK_BIT_BUFFER and GET_BITS. When there aren't enough 639f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * bits, jpeg_fill_bit_buffer is called; it will attempt to fill get_buffer 649f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * as full as possible (not just to the number of bits needed; this 659f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * prefetching reduces the overhead cost of calling jpeg_fill_bit_buffer). 669f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * Note that jpeg_fill_bit_buffer may return FALSE to indicate suspension. 679f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * On TRUE return, jpeg_fill_bit_buffer guarantees that get_buffer contains 689f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * at least the requested number of bits --- dummy zeroes are inserted if 699f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * necessary. 709f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project */ 719f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 729f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Projecttypedef INT32 bit_buf_type; /* type of bit-extraction buffer */ 739f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project#define BIT_BUF_SIZE 32 /* size of buffer in bits */ 743147fbe7688fc353e6ae03825a37cf101a4ee01dJoseph Wen#define LOG_TWO_BIT_BUF_SIZE 5 /* log_2(BIT_BUF_SIZE) */ 759f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 769f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project/* If long is > 32 bits on your machine, and shifting/masking longs is 779f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * reasonably fast, making bit_buf_type be long and setting BIT_BUF_SIZE 789f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * appropriately should be a win. Unfortunately we can't define the size 799f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * with something like #define BIT_BUF_SIZE (sizeof(bit_buf_type)*8) 809f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * because not all machines measure sizeof in 8-bit bytes. 819f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project */ 829f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 839f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Projecttypedef struct { /* Bitreading state saved across MCUs */ 849f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project bit_buf_type get_buffer; /* current bit-extraction buffer */ 859f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project int bits_left; /* # of unused bits in it */ 869f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project} bitread_perm_state; 879f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 889f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Projecttypedef struct { /* Bitreading working state within an MCU */ 899f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project /* Current data source location */ 909f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project /* We need a copy, rather than munging the original, in case of suspension */ 919f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project const JOCTET * next_input_byte; /* => next byte to read from source */ 929f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project size_t bytes_in_buffer; /* # of bytes remaining in source buffer */ 939f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project /* Bit input buffer --- note these values are kept in register variables, 949f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * not in this struct, inside the inner loops. 959f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project */ 969f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project bit_buf_type get_buffer; /* current bit-extraction buffer */ 979f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project int bits_left; /* # of unused bits in it */ 989f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project /* Pointer needed by jpeg_fill_bit_buffer. */ 999f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project j_decompress_ptr cinfo; /* back link to decompress master record */ 1009f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project} bitread_working_state; 1019f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 1029f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project/* Macros to declare and load/save bitread local variables. */ 1039f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project#define BITREAD_STATE_VARS \ 1049f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project register bit_buf_type get_buffer; \ 1059f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project register int bits_left; \ 1069f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project bitread_working_state br_state 1079f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 1089f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project#define BITREAD_LOAD_STATE(cinfop,permstate) \ 1099f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project br_state.cinfo = cinfop; \ 1109f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project br_state.next_input_byte = cinfop->src->next_input_byte; \ 1119f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project br_state.bytes_in_buffer = cinfop->src->bytes_in_buffer; \ 1129f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project get_buffer = permstate.get_buffer; \ 1139f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project bits_left = permstate.bits_left; 1149f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 1159f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project#define BITREAD_SAVE_STATE(cinfop,permstate) \ 1169f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project cinfop->src->next_input_byte = br_state.next_input_byte; \ 1179f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project cinfop->src->bytes_in_buffer = br_state.bytes_in_buffer; \ 1189f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project permstate.get_buffer = get_buffer; \ 1199f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project permstate.bits_left = bits_left 1209f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 1219f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project/* 1229f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * These macros provide the in-line portion of bit fetching. 1239f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * Use CHECK_BIT_BUFFER to ensure there are N bits in get_buffer 1249f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * before using GET_BITS, PEEK_BITS, or DROP_BITS. 1259f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * The variables get_buffer and bits_left are assumed to be locals, 1269f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * but the state struct might not be (jpeg_huff_decode needs this). 1279f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * CHECK_BIT_BUFFER(state,n,action); 1289f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * Ensure there are N bits in get_buffer; if suspend, take action. 1299f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * val = GET_BITS(n); 1309f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * Fetch next N bits. 1319f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * val = PEEK_BITS(n); 1329f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * Fetch next N bits without removing them from the buffer. 1339f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * DROP_BITS(n); 1349f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * Discard next N bits. 1359f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * The value N should be a simple variable, not an expression, because it 1369f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * is evaluated multiple times. 1379f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project */ 1389f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 1399f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project#define CHECK_BIT_BUFFER(state,nbits,action) \ 1409f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project { if (bits_left < (nbits)) { \ 1419f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project if (! jpeg_fill_bit_buffer(&(state),get_buffer,bits_left,nbits)) \ 1429f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project { action; } \ 1439f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project get_buffer = (state).get_buffer; bits_left = (state).bits_left; } } 1449f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 1459f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project#define GET_BITS(nbits) \ 1469f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project (((int) (get_buffer >> (bits_left -= (nbits)))) & ((1<<(nbits))-1)) 1479f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 1489f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project#define PEEK_BITS(nbits) \ 1499f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project (((int) (get_buffer >> (bits_left - (nbits)))) & ((1<<(nbits))-1)) 1509f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 1519f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project#define DROP_BITS(nbits) \ 1529f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project (bits_left -= (nbits)) 1539f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 1549f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project/* Load up the bit buffer to a depth of at least nbits */ 1559f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source ProjectEXTERN(boolean) jpeg_fill_bit_buffer 1569f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project JPP((bitread_working_state * state, register bit_buf_type get_buffer, 1579f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project register int bits_left, int nbits)); 1589f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 1599f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 1609f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project/* 1619f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * Code for extracting next Huffman-coded symbol from input bit stream. 1629f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * Again, this is time-critical and we make the main paths be macros. 1639f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * 1649f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * We use a lookahead table to process codes of up to HUFF_LOOKAHEAD bits 1659f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * without looping. Usually, more than 95% of the Huffman codes will be 8 1669f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * or fewer bits long. The few overlength codes are handled with a loop, 1679f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * which need not be inline code. 1689f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * 1699f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * Notes about the HUFF_DECODE macro: 1709f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * 1. Near the end of the data segment, we may fail to get enough bits 1719f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * for a lookahead. In that case, we do it the hard way. 1729f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * 2. If the lookahead table contains no entry, the next code must be 1739f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * more than HUFF_LOOKAHEAD bits long. 1749f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project * 3. jpeg_huff_decode returns -1 if forced to suspend. 1759f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project */ 1769f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 1779f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project#define HUFF_DECODE(result,state,htbl,failaction,slowlabel) \ 1789f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project{ register int nb, look; \ 1799f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project if (bits_left < HUFF_LOOKAHEAD) { \ 1809f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project if (! jpeg_fill_bit_buffer(&state,get_buffer,bits_left, 0)) {failaction;} \ 1819f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project get_buffer = state.get_buffer; bits_left = state.bits_left; \ 1829f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project if (bits_left < HUFF_LOOKAHEAD) { \ 1839f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project nb = 1; goto slowlabel; \ 1849f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project } \ 1859f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project } \ 1869f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project look = PEEK_BITS(HUFF_LOOKAHEAD); \ 1879f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project if ((nb = htbl->look_nbits[look]) != 0) { \ 1889f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project DROP_BITS(nb); \ 1899f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project result = htbl->look_sym[look]; \ 1909f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project } else { \ 1919f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project nb = HUFF_LOOKAHEAD+1; \ 1929f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Projectslowlabel: \ 1939f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project if ((result=jpeg_huff_decode(&state,get_buffer,bits_left,htbl,nb)) < 0) \ 1949f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project { failaction; } \ 1959f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project get_buffer = state.get_buffer; bits_left = state.bits_left; \ 1969f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project } \ 1979f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project} 1989f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project 1999f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project/* Out-of-line case for Huffman code fetching */ 2009f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source ProjectEXTERN(int) jpeg_huff_decode 2019f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project JPP((bitread_working_state * state, register bit_buf_type get_buffer, 2029f5d49a1588e438ae7ceabd0c94172117e3303aaThe Android Open Source Project register int bits_left, d_derived_tbl * htbl, int min_bits)); 203