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Diffstat (limited to 'faad2/src/libfaad/hcr.c')
| -rw-r--r-- | faad2/src/libfaad/hcr.c | 432 |
1 files changed, 432 insertions, 0 deletions
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 <stdlib.h>
+#include <string.h>
+
+#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
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