From cc2160de5cc05dc3aa77f3a34358e66f6193c8c9 Mon Sep 17 00:00:00 2001 From: Michał Cichoń Date: Tue, 26 Jun 2012 20:35:30 +0200 Subject: Add support for AAC. --- faad2/src/libfaad/hcr.c | 432 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 432 insertions(+) create mode 100644 faad2/src/libfaad/hcr.c (limited to 'faad2/src/libfaad/hcr.c') diff --git a/faad2/src/libfaad/hcr.c b/faad2/src/libfaad/hcr.c new file mode 100644 index 0000000..c4901b3 --- /dev/null +++ b/faad2/src/libfaad/hcr.c @@ -0,0 +1,432 @@ +/* +** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding +** Copyright (C) 2003-2005 M. Bakker, Nero AG, http://www.nero.com +** +** This program is free software; you can redistribute it and/or modify +** it under the terms of the GNU General Public License as published by +** the Free Software Foundation; either version 2 of the License, or +** (at your option) any later version. +** +** This program is distributed in the hope that it will be useful, +** but WITHOUT ANY WARRANTY; without even the implied warranty of +** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +** GNU General Public License for more details. +** +** You should have received a copy of the GNU General Public License +** along with this program; if not, write to the Free Software +** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. +** +** Any non-GPL usage of this software or parts of this software is strictly +** forbidden. +** +** The "appropriate copyright message" mentioned in section 2c of the GPLv2 +** must read: "Code from FAAD2 is copyright (c) Nero AG, www.nero.com" +** +** Commercial non-GPL licensing of this software is possible. +** For more info contact Nero AG through Mpeg4AAClicense@nero.com. +** +** $Id: hcr.c,v 1.26 2009/01/26 23:51:15 menno Exp $ +**/ + +#include "common.h" +#include "structs.h" + +#include +#include + +#include "specrec.h" +#include "huffman.h" + +/* ISO/IEC 14496-3/Amd.1 + * 8.5.3.3: Huffman Codeword Reordering for AAC spectral data (HCR) + * + * HCR devides the spectral data in known fixed size segments, and + * sorts it by the importance of the data. The importance is firstly + * the (lower) position in the spectrum, and secondly the largest + * value in the used codebook. + * The most important data is written at the start of each segment + * (at known positions), the remaining data is interleaved inbetween, + * with the writing direction alternating. + * Data length is not increased. +*/ + +#ifdef ERROR_RESILIENCE + +/* 8.5.3.3.1 Pre-sorting */ + +#define NUM_CB 6 +#define NUM_CB_ER 22 +#define MAX_CB 32 +#define VCB11_FIRST 16 +#define VCB11_LAST 31 + +static const uint8_t PreSortCB_STD[NUM_CB] = + { 11, 9, 7, 5, 3, 1}; + +static const uint8_t PreSortCB_ER[NUM_CB_ER] = + { 11, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 9, 7, 5, 3, 1}; + +/* 8.5.3.3.2 Derivation of segment width */ + +static const uint8_t maxCwLen[MAX_CB] = {0, 11, 9, 20, 16, 13, 11, 14, 12, 17, 14, 49, + 0, 0, 0, 0, 14, 17, 21, 21, 25, 25, 29, 29, 29, 29, 33, 33, 33, 37, 37, 41}; + +#define segmentWidth(cb) min(maxCwLen[cb], ics->length_of_longest_codeword) + +/* bit-twiddling helpers */ +static const uint8_t S[] = {1, 2, 4, 8, 16}; +static const uint32_t B[] = {0x55555555, 0x33333333, 0x0F0F0F0F, 0x00FF00FF, 0x0000FFFF}; + +typedef struct +{ + uint8_t cb; + uint8_t decoded; + uint16_t sp_offset; + bits_t bits; +} codeword_t; + +/* rewind and reverse */ +/* 32 bit version */ +static uint32_t rewrev_word(uint32_t v, const uint8_t len) +{ + /* 32 bit reverse */ + v = ((v >> S[0]) & B[0]) | ((v << S[0]) & ~B[0]); + v = ((v >> S[1]) & B[1]) | ((v << S[1]) & ~B[1]); + v = ((v >> S[2]) & B[2]) | ((v << S[2]) & ~B[2]); + v = ((v >> S[3]) & B[3]) | ((v << S[3]) & ~B[3]); + v = ((v >> S[4]) & B[4]) | ((v << S[4]) & ~B[4]); + + /* shift off low bits */ + v >>= (32 - len); + + return v; +} + +/* 64 bit version */ +static void rewrev_lword(uint32_t *hi, uint32_t *lo, const uint8_t len) +{ + if (len <= 32) { + *hi = 0; + *lo = rewrev_word(*lo, len); + } else + { + uint32_t t = *hi, v = *lo; + + /* double 32 bit reverse */ + v = ((v >> S[0]) & B[0]) | ((v << S[0]) & ~B[0]); + t = ((t >> S[0]) & B[0]) | ((t << S[0]) & ~B[0]); + v = ((v >> S[1]) & B[1]) | ((v << S[1]) & ~B[1]); + t = ((t >> S[1]) & B[1]) | ((t << S[1]) & ~B[1]); + v = ((v >> S[2]) & B[2]) | ((v << S[2]) & ~B[2]); + t = ((t >> S[2]) & B[2]) | ((t << S[2]) & ~B[2]); + v = ((v >> S[3]) & B[3]) | ((v << S[3]) & ~B[3]); + t = ((t >> S[3]) & B[3]) | ((t << S[3]) & ~B[3]); + v = ((v >> S[4]) & B[4]) | ((v << S[4]) & ~B[4]); + t = ((t >> S[4]) & B[4]) | ((t << S[4]) & ~B[4]); + + /* last 32<>32 bit swap is implicit below */ + + /* shift off low bits (this is really only one 64 bit shift) */ + *lo = (t >> (64 - len)) | (v << (len - 32)); + *hi = v >> (64 - len); + } +} + + +/* bits_t version */ +static void rewrev_bits(bits_t *bits) +{ + if (bits->len == 0) return; + rewrev_lword(&bits->bufb, &bits->bufa, bits->len); +} + + +/* merge bits of a to b */ +static void concat_bits(bits_t *b, bits_t *a) +{ + uint32_t bl, bh, al, ah; + + if (a->len == 0) return; + + al = a->bufa; + ah = a->bufb; + + if (b->len > 32) + { + /* maskoff superfluous high b bits */ + bl = b->bufa; + bh = b->bufb & ((1 << (b->len-32)) - 1); + /* left shift a b->len bits */ + ah = al << (b->len - 32); + al = 0; + } else { + bl = b->bufa & ((1 << (b->len)) - 1); + bh = 0; + ah = (ah << (b->len)) | (al >> (32 - b->len)); + al = al << b->len; + } + + /* merge */ + b->bufa = bl | al; + b->bufb = bh | ah; + + b->len += a->len; +} + +static uint8_t is_good_cb(uint8_t this_CB, uint8_t this_sec_CB) +{ + /* only want spectral data CB's */ + if ((this_sec_CB > ZERO_HCB && this_sec_CB <= ESC_HCB) || (this_sec_CB >= VCB11_FIRST && this_sec_CB <= VCB11_LAST)) + { + if (this_CB < ESC_HCB) + { + /* normal codebook pairs */ + return ((this_sec_CB == this_CB) || (this_sec_CB == this_CB + 1)); + } else + { + /* escape codebook */ + return (this_sec_CB == this_CB); + } + } + return 0; +} + +static void read_segment(bits_t *segment, uint8_t segwidth, bitfile *ld) +{ + segment->len = segwidth; + + if (segwidth > 32) + { + segment->bufb = faad_getbits(ld, segwidth - 32); + segment->bufa = faad_getbits(ld, 32); + + } else { + segment->bufa = faad_getbits(ld, segwidth); + segment->bufb = 0; + } +} + +static void fill_in_codeword(codeword_t *codeword, uint16_t index, uint16_t sp, uint8_t cb) +{ + codeword[index].sp_offset = sp; + codeword[index].cb = cb; + codeword[index].decoded = 0; + codeword[index].bits.len = 0; +} + +uint8_t reordered_spectral_data(NeAACDecStruct *hDecoder, ic_stream *ics, + bitfile *ld, int16_t *spectral_data) +{ + uint16_t PCWs_done; + uint16_t numberOfSegments, numberOfSets, numberOfCodewords; + + codeword_t codeword[512]; + bits_t segment[512]; + + uint16_t sp_offset[8]; + uint16_t g, i, sortloop, set, bitsread; + uint16_t bitsleft, codewordsleft; + uint8_t w_idx, sfb, this_CB, last_CB, this_sec_CB; + + const uint16_t nshort = hDecoder->frameLength/8; + const uint16_t sp_data_len = ics->length_of_reordered_spectral_data; + + const uint8_t *PreSortCb; + + /* no data (e.g. silence) */ + if (sp_data_len == 0) + return 0; + + /* since there is spectral data, at least one codeword has nonzero length */ + if (ics->length_of_longest_codeword == 0) + return 10; + + if (sp_data_len < ics->length_of_longest_codeword) + return 10; + + sp_offset[0] = 0; + for (g = 1; g < ics->num_window_groups; g++) + { + sp_offset[g] = sp_offset[g-1] + nshort*ics->window_group_length[g-1]; + } + + PCWs_done = 0; + numberOfSegments = 0; + numberOfCodewords = 0; + bitsread = 0; + + /* VCB11 code books in use */ + if (hDecoder->aacSectionDataResilienceFlag) + { + PreSortCb = PreSortCB_ER; + last_CB = NUM_CB_ER; + } else + { + PreSortCb = PreSortCB_STD; + last_CB = NUM_CB; + } + + /* step 1: decode PCW's (set 0), and stuff data in easier-to-use format */ + for (sortloop = 0; sortloop < last_CB; sortloop++) + { + /* select codebook to process this pass */ + this_CB = PreSortCb[sortloop]; + + /* loop over sfbs */ + for (sfb = 0; sfb < ics->max_sfb; sfb++) + { + /* loop over all in this sfb, 4 lines per loop */ + for (w_idx = 0; 4*w_idx < (min(ics->swb_offset[sfb+1], ics->swb_offset_max) - ics->swb_offset[sfb]); w_idx++) + { + for(g = 0; g < ics->num_window_groups; g++) + { + for (i = 0; i < ics->num_sec[g]; i++) + { + /* check whether sfb used here is the one we want to process */ + if ((ics->sect_start[g][i] <= sfb) && (ics->sect_end[g][i] > sfb)) + { + /* check whether codebook used here is the one we want to process */ + this_sec_CB = ics->sect_cb[g][i]; + + if (is_good_cb(this_CB, this_sec_CB)) + { + /* precalculate some stuff */ + uint16_t sect_sfb_size = ics->sect_sfb_offset[g][sfb+1] - ics->sect_sfb_offset[g][sfb]; + uint8_t inc = (this_sec_CB < FIRST_PAIR_HCB) ? QUAD_LEN : PAIR_LEN; + uint16_t group_cws_count = (4*ics->window_group_length[g])/inc; + uint8_t segwidth = segmentWidth(this_sec_CB); + uint16_t cws; + + /* read codewords until end of sfb or end of window group (shouldn't only 1 trigger?) */ + for (cws = 0; (cws < group_cws_count) && ((cws + w_idx*group_cws_count) < sect_sfb_size); cws++) + { + uint16_t sp = sp_offset[g] + ics->sect_sfb_offset[g][sfb] + inc * (cws + w_idx*group_cws_count); + + /* read and decode PCW */ + if (!PCWs_done) + { + /* read in normal segments */ + if (bitsread + segwidth <= sp_data_len) + { + read_segment(&segment[numberOfSegments], segwidth, ld); + bitsread += segwidth; + + huffman_spectral_data_2(this_sec_CB, &segment[numberOfSegments], &spectral_data[sp]); + + /* keep leftover bits */ + rewrev_bits(&segment[numberOfSegments]); + + numberOfSegments++; + } else { + /* remaining stuff after last segment, we unfortunately couldn't read + this in earlier because it might not fit in 64 bits. since we already + decoded (and removed) the PCW it is now guaranteed to fit */ + if (bitsread < sp_data_len) + { + const uint8_t additional_bits = sp_data_len - bitsread; + + read_segment(&segment[numberOfSegments], additional_bits, ld); + segment[numberOfSegments].len += segment[numberOfSegments-1].len; + rewrev_bits(&segment[numberOfSegments]); + + if (segment[numberOfSegments-1].len > 32) + { + segment[numberOfSegments-1].bufb = segment[numberOfSegments].bufb + + showbits_hcr(&segment[numberOfSegments-1], segment[numberOfSegments-1].len - 32); + segment[numberOfSegments-1].bufa = segment[numberOfSegments].bufa + + showbits_hcr(&segment[numberOfSegments-1], 32); + } else { + segment[numberOfSegments-1].bufa = segment[numberOfSegments].bufa + + showbits_hcr(&segment[numberOfSegments-1], segment[numberOfSegments-1].len); + segment[numberOfSegments-1].bufb = segment[numberOfSegments].bufb; + } + segment[numberOfSegments-1].len += additional_bits; + } + bitsread = sp_data_len; + PCWs_done = 1; + + fill_in_codeword(codeword, 0, sp, this_sec_CB); + } + } else { + fill_in_codeword(codeword, numberOfCodewords - numberOfSegments, sp, this_sec_CB); + } + numberOfCodewords++; + } + } + } + } + } + } + } + } + + if (numberOfSegments == 0) + return 10; + + numberOfSets = numberOfCodewords / numberOfSegments; + + /* step 2: decode nonPCWs */ + for (set = 1; set <= numberOfSets; set++) + { + uint16_t trial; + + for (trial = 0; trial < numberOfSegments; trial++) + { + uint16_t codewordBase; + + for (codewordBase = 0; codewordBase < numberOfSegments; codewordBase++) + { + const uint16_t segment_idx = (trial + codewordBase) % numberOfSegments; + const uint16_t codeword_idx = codewordBase + set*numberOfSegments - numberOfSegments; + + /* data up */ + if (codeword_idx >= numberOfCodewords - numberOfSegments) break; + + if (!codeword[codeword_idx].decoded && segment[segment_idx].len > 0) + { + uint8_t tmplen; + + if (codeword[codeword_idx].bits.len != 0) + concat_bits(&segment[segment_idx], &codeword[codeword_idx].bits); + + tmplen = segment[segment_idx].len; + + if (huffman_spectral_data_2(codeword[codeword_idx].cb, &segment[segment_idx], + &spectral_data[codeword[codeword_idx].sp_offset]) >= 0) + { + codeword[codeword_idx].decoded = 1; + } else + { + codeword[codeword_idx].bits = segment[segment_idx]; + codeword[codeword_idx].bits.len = tmplen; + } + + } + } + } + for (i = 0; i < numberOfSegments; i++) + rewrev_bits(&segment[i]); + } + +#if 0 // Seems to give false errors + bitsleft = 0; + + for (i = 0; i < numberOfSegments && !bitsleft; i++) + bitsleft += segment[i].len; + + if (bitsleft) return 10; + + codewordsleft = 0; + + for (i = 0; (i < numberOfCodewords - numberOfSegments) && (!codewordsleft); i++) + if (!codeword[i].decoded) + codewordsleft++; + + if (codewordsleft) return 10; +#endif + + + return 0; + +} +#endif -- cgit v1.2.3