| /* |
| ** 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: rvlc.c,v 1.21 2007/11/01 12:33:34 menno Exp $ |
| **/ |
| |
| /* RVLC scalefactor decoding |
| * |
| * RVLC works like this: |
| * 1. Only symmetric huffman codewords are used |
| * 2. Total length of the scalefactor data is stored in the bitsream |
| * 3. Scalefactors are DPCM coded |
| * 4. Next to the starting value for DPCM the ending value is also stored |
| * |
| * With all this it is possible to read the scalefactor data from 2 sides. |
| * If there is a bit error in the scalefactor data it is possible to start |
| * decoding from the other end of the data, to find all but 1 scalefactor. |
| */ |
| #include <stdlib.h> |
| #include "common.h" |
| #include "structs.h" |
| |
| |
| #include "syntax.h" |
| #include "bits.h" |
| #include "rvlc.h" |
| |
| static /*INLINE*/ uint32_t faad_getbits_rev(bitfile *ld, uint32_t n |
| DEBUGDEC) |
| { |
| uint32_t ret; |
| |
| if (n == 0) { |
| return 0; |
| } |
| |
| ret = faad_showbits_rev(ld, n); |
| faad_flushbits_rev(ld, n); |
| |
| #ifdef ANALYSIS |
| if (print) { |
| fprintf(stdout, "%4d %2d bits, val: %4d, variable: %d %s\n", dbg_count++, n, ret, var, dbg); |
| } |
| #endif |
| |
| return ret; |
| } |
| |
| #ifdef ERROR_RESILIENCE |
| |
| //#define PRINT_RVLC |
| |
| /* static function declarations */ |
| static uint8_t rvlc_decode_sf_forward(ic_stream *ics, |
| bitfile *ld_sf, |
| bitfile *ld_esc, |
| uint8_t *is_used); |
| #if 0 |
| static uint8_t rvlc_decode_sf_reverse(ic_stream *ics, |
| bitfile *ld_sf, |
| bitfile *ld_esc, |
| uint8_t is_used); |
| #endif |
| static int8_t rvlc_huffman_sf(bitfile *ld_sf, bitfile *ld_esc, |
| int8_t direction); |
| static int8_t rvlc_huffman_esc(bitfile *ld_esc, int8_t direction); |
| |
| |
| uint8_t rvlc_scale_factor_data(ic_stream *ics, bitfile *ld) |
| { |
| uint8_t bits = 9; |
| |
| ics->sf_concealment = faad_get1bit(ld |
| DEBUGVAR(1, 149, "rvlc_scale_factor_data(): sf_concealment")); |
| ics->rev_global_gain = (uint8_t)faad_getbits(ld, 8 |
| DEBUGVAR(1, 150, "rvlc_scale_factor_data(): rev_global_gain")); |
| |
| if (ics->window_sequence == EIGHT_SHORT_SEQUENCE) { |
| bits = 11; |
| } |
| |
| /* the number of bits used for the huffman codewords */ |
| ics->length_of_rvlc_sf = (uint16_t)faad_getbits(ld, bits |
| DEBUGVAR(1, 151, "rvlc_scale_factor_data(): length_of_rvlc_sf")); |
| |
| if (ics->noise_used) { |
| ics->dpcm_noise_nrg = (uint16_t)faad_getbits(ld, 9 |
| DEBUGVAR(1, 152, "rvlc_scale_factor_data(): dpcm_noise_nrg")); |
| |
| ics->length_of_rvlc_sf -= 9; |
| } |
| |
| ics->sf_escapes_present = faad_get1bit(ld |
| DEBUGVAR(1, 153, "rvlc_scale_factor_data(): sf_escapes_present")); |
| |
| if (ics->sf_escapes_present) { |
| ics->length_of_rvlc_escapes = (uint8_t)faad_getbits(ld, 8 |
| DEBUGVAR(1, 154, "rvlc_scale_factor_data(): length_of_rvlc_escapes")); |
| } |
| |
| if (ics->noise_used) { |
| ics->dpcm_noise_last_position = (uint16_t)faad_getbits(ld, 9 |
| DEBUGVAR(1, 155, "rvlc_scale_factor_data(): dpcm_noise_last_position")); |
| } |
| |
| return 0; |
| } |
| |
| uint8_t rvlc_decode_scale_factors(ic_stream *ics, bitfile *ld) |
| { |
| uint8_t result; |
| uint8_t intensity_used = 0; |
| uint8_t *rvlc_sf_buffer = NULL; |
| uint8_t *rvlc_esc_buffer = NULL; |
| bitfile ld_rvlc_sf, ld_rvlc_esc; |
| memset(&ld_rvlc_sf, 0, sizeof(ld_rvlc_sf)); |
| memset(&ld_rvlc_esc, 0, sizeof(ld_rvlc_esc)); |
| // bitfile ld_rvlc_sf_rev, ld_rvlc_esc_rev; |
| |
| if (ics->length_of_rvlc_sf > 0) { |
| /* We read length_of_rvlc_sf bits here to put it in a |
| seperate bitfile. |
| */ |
| rvlc_sf_buffer = faad_getbitbuffer(ld, ics->length_of_rvlc_sf |
| DEBUGVAR(1, 156, "rvlc_decode_scale_factors(): bitbuffer: length_of_rvlc_sf")); |
| |
| faad_initbits(&ld_rvlc_sf, (void*)rvlc_sf_buffer, bit2byte(ics->length_of_rvlc_sf)); |
| // faad_initbits_rev(&ld_rvlc_sf_rev, (void*)rvlc_sf_buffer, |
| // ics->length_of_rvlc_sf); |
| } |
| |
| if (ics->sf_escapes_present) { |
| /* We read length_of_rvlc_escapes bits here to put it in a |
| seperate bitfile. |
| */ |
| rvlc_esc_buffer = faad_getbitbuffer(ld, ics->length_of_rvlc_escapes |
| DEBUGVAR(1, 157, "rvlc_decode_scale_factors(): bitbuffer: length_of_rvlc_escapes")); |
| |
| faad_initbits(&ld_rvlc_esc, (void*)rvlc_esc_buffer, bit2byte(ics->length_of_rvlc_escapes)); |
| // faad_initbits_rev(&ld_rvlc_esc_rev, (void*)rvlc_esc_buffer, |
| // ics->length_of_rvlc_escapes); |
| } |
| |
| /* decode the rvlc scale factors and escapes */ |
| result = rvlc_decode_sf_forward(ics, &ld_rvlc_sf, |
| &ld_rvlc_esc, &intensity_used); |
| // result = rvlc_decode_sf_reverse(ics, &ld_rvlc_sf_rev, |
| // &ld_rvlc_esc_rev, intensity_used); |
| |
| |
| if (rvlc_esc_buffer) { |
| faad_free(rvlc_esc_buffer); |
| } |
| if (rvlc_sf_buffer) { |
| faad_free(rvlc_sf_buffer); |
| } |
| |
| if (ics->length_of_rvlc_sf > 0) { |
| faad_endbits(&ld_rvlc_sf); |
| } |
| if (ics->sf_escapes_present) { |
| faad_endbits(&ld_rvlc_esc); |
| } |
| |
| return result; |
| } |
| |
| static uint8_t rvlc_decode_sf_forward(ic_stream *ics, bitfile *ld_sf, bitfile *ld_esc, |
| uint8_t *intensity_used) |
| { |
| int8_t g, sfb; |
| int8_t t = 0; |
| int8_t error = 0; |
| int8_t noise_pcm_flag = 1; |
| |
| int16_t scale_factor = ics->global_gain; |
| int16_t is_position = 0; |
| int16_t noise_energy = ics->global_gain - 90 - 256; |
| |
| #ifdef PRINT_RVLC |
| printf("\nglobal_gain: %d\n", ics->global_gain); |
| #endif |
| |
| for (g = 0; g < ics->num_window_groups; g++) { |
| for (sfb = 0; sfb < ics->max_sfb; sfb++) { |
| if (error) { |
| ics->scale_factors[g][sfb] = 0; |
| } else { |
| switch (ics->sfb_cb[g][sfb]) { |
| case ZERO_HCB: /* zero book */ |
| ics->scale_factors[g][sfb] = 0; |
| break; |
| case INTENSITY_HCB: /* intensity books */ |
| case INTENSITY_HCB2: |
| |
| *intensity_used = 1; |
| |
| /* decode intensity position */ |
| t = rvlc_huffman_sf(ld_sf, ld_esc, +1); |
| |
| is_position += t; |
| ics->scale_factors[g][sfb] = is_position; |
| |
| break; |
| case NOISE_HCB: /* noise books */ |
| |
| /* decode noise energy */ |
| if (noise_pcm_flag) { |
| int16_t n = ics->dpcm_noise_nrg; |
| noise_pcm_flag = 0; |
| noise_energy += n; |
| } else { |
| t = rvlc_huffman_sf(ld_sf, ld_esc, +1); |
| noise_energy += t; |
| } |
| |
| ics->scale_factors[g][sfb] = noise_energy; |
| |
| break; |
| default: /* spectral books */ |
| |
| /* decode scale factor */ |
| t = rvlc_huffman_sf(ld_sf, ld_esc, +1); |
| |
| scale_factor += t; |
| if (scale_factor < 0) { |
| return 4; |
| } |
| |
| ics->scale_factors[g][sfb] = scale_factor; |
| |
| break; |
| } |
| #ifdef PRINT_RVLC |
| printf("%3d:%4d%4d\n", sfb, ics->sfb_cb[g][sfb], |
| ics->scale_factors[g][sfb]); |
| #endif |
| if (t == 99) { |
| error = 1; |
| } |
| } |
| } |
| } |
| #ifdef PRINT_RVLC |
| printf("\n\n"); |
| #endif |
| |
| return 0; |
| } |
| |
| #if 0 // not used right now, doesn't work correctly yet |
| static uint8_t rvlc_decode_sf_reverse(ic_stream *ics, bitfile *ld_sf, bitfile *ld_esc, |
| uint8_t intensity_used) |
| { |
| int8_t g, sfb; |
| int8_t t = 0; |
| int8_t error = 0; |
| int8_t noise_pcm_flag = 1, is_pcm_flag = 1, sf_pcm_flag = 1; |
| |
| int16_t scale_factor = ics->rev_global_gain; |
| int16_t is_position = 0; |
| int16_t noise_energy = ics->rev_global_gain; |
| |
| #ifdef PRINT_RVLC |
| printf("\nrev_global_gain: %d\n", ics->rev_global_gain); |
| #endif |
| |
| if (intensity_used) { |
| is_position = rvlc_huffman_sf(ld_sf, ld_esc, -1); |
| #ifdef PRINT_RVLC |
| printf("is_position: %d\n", is_position); |
| #endif |
| } |
| |
| for (g = ics->num_window_groups - 1; g >= 0; g--) { |
| for (sfb = ics->max_sfb - 1; sfb >= 0; sfb--) { |
| if (error) { |
| ics->scale_factors[g][sfb] = 0; |
| } else { |
| switch (ics->sfb_cb[g][sfb]) { |
| case ZERO_HCB: /* zero book */ |
| ics->scale_factors[g][sfb] = 0; |
| break; |
| case INTENSITY_HCB: /* intensity books */ |
| case INTENSITY_HCB2: |
| |
| if (is_pcm_flag) { |
| is_pcm_flag = 0; |
| ics->scale_factors[g][sfb] = is_position; |
| } else { |
| t = rvlc_huffman_sf(ld_sf, ld_esc, -1); |
| is_position -= t; |
| |
| ics->scale_factors[g][sfb] = (uint8_t)is_position; |
| } |
| break; |
| case NOISE_HCB: /* noise books */ |
| |
| /* decode noise energy */ |
| if (noise_pcm_flag) { |
| noise_pcm_flag = 0; |
| noise_energy = ics->dpcm_noise_last_position; |
| } else { |
| t = rvlc_huffman_sf(ld_sf, ld_esc, -1); |
| noise_energy -= t; |
| } |
| |
| ics->scale_factors[g][sfb] = (uint8_t)noise_energy; |
| break; |
| default: /* spectral books */ |
| |
| if (sf_pcm_flag || (sfb == 0)) { |
| sf_pcm_flag = 0; |
| if (sfb == 0) { |
| scale_factor = ics->global_gain; |
| } |
| } else { |
| /* decode scale factor */ |
| t = rvlc_huffman_sf(ld_sf, ld_esc, -1); |
| scale_factor -= t; |
| } |
| |
| if (scale_factor < 0) { |
| return 4; |
| } |
| |
| ics->scale_factors[g][sfb] = (uint8_t)scale_factor; |
| break; |
| } |
| #ifdef PRINT_RVLC |
| printf("%3d:%4d%4d\n", sfb, ics->sfb_cb[g][sfb], |
| ics->scale_factors[g][sfb]); |
| #endif |
| if (t == 99) { |
| error = 1; |
| } |
| } |
| } |
| } |
| |
| #ifdef PRINT_RVLC |
| printf("\n\n"); |
| #endif |
| |
| return 0; |
| } |
| #endif |
| |
| /* index == 99 means not allowed codeword */ |
| static rvlc_huff_table book_rvlc[] = { |
| /*index length codeword */ |
| { 0, 1, 0 }, /* 0 */ |
| { -1, 3, 5 }, /* 101 */ |
| { 1, 3, 7 }, /* 111 */ |
| { -2, 4, 9 }, /* 1001 */ |
| { -3, 5, 17 }, /* 10001 */ |
| { 2, 5, 27 }, /* 11011 */ |
| { -4, 6, 33 }, /* 100001 */ |
| { 99, 6, 50 }, /* 110010 */ |
| { 3, 6, 51 }, /* 110011 */ |
| { 99, 6, 52 }, /* 110100 */ |
| { -7, 7, 65 }, /* 1000001 */ |
| { 99, 7, 96 }, /* 1100000 */ |
| { 99, 7, 98 }, /* 1100010 */ |
| { 7, 7, 99 }, /* 1100011 */ |
| { 4, 7, 107 }, /* 1101011 */ |
| { -5, 8, 129 }, /* 10000001 */ |
| { 99, 8, 194 }, /* 11000010 */ |
| { 5, 8, 195 }, /* 11000011 */ |
| { 99, 8, 212 }, /* 11010100 */ |
| { 99, 9, 256 }, /* 100000000 */ |
| { -6, 9, 257 }, /* 100000001 */ |
| { 99, 9, 426 }, /* 110101010 */ |
| { 6, 9, 427 }, /* 110101011 */ |
| { 99, 10, 0 } /* Shouldn't come this far */ |
| }; |
| |
| static rvlc_huff_table book_escape[] = { |
| /*index length codeword */ |
| { 1, 2, 0 }, |
| { 0, 2, 2 }, |
| { 3, 3, 2 }, |
| { 2, 3, 6 }, |
| { 4, 4, 14 }, |
| { 7, 5, 13 }, |
| { 6, 5, 15 }, |
| { 5, 5, 31 }, |
| { 11, 6, 24 }, |
| { 10, 6, 25 }, |
| { 9, 6, 29 }, |
| { 8, 6, 61 }, |
| { 13, 7, 56 }, |
| { 12, 7, 120 }, |
| { 15, 8, 114 }, |
| { 14, 8, 242 }, |
| { 17, 9, 230 }, |
| { 16, 9, 486 }, |
| { 19, 10, 463 }, |
| { 18, 10, 974 }, |
| { 22, 11, 925 }, |
| { 20, 11, 1950 }, |
| { 21, 11, 1951 }, |
| { 23, 12, 1848 }, |
| { 25, 13, 3698 }, |
| { 24, 14, 7399 }, |
| { 26, 15, 14797 }, |
| { 49, 19, 236736 }, |
| { 50, 19, 236737 }, |
| { 51, 19, 236738 }, |
| { 52, 19, 236739 }, |
| { 53, 19, 236740 }, |
| { 27, 20, 473482 }, |
| { 28, 20, 473483 }, |
| { 29, 20, 473484 }, |
| { 30, 20, 473485 }, |
| { 31, 20, 473486 }, |
| { 32, 20, 473487 }, |
| { 33, 20, 473488 }, |
| { 34, 20, 473489 }, |
| { 35, 20, 473490 }, |
| { 36, 20, 473491 }, |
| { 37, 20, 473492 }, |
| { 38, 20, 473493 }, |
| { 39, 20, 473494 }, |
| { 40, 20, 473495 }, |
| { 41, 20, 473496 }, |
| { 42, 20, 473497 }, |
| { 43, 20, 473498 }, |
| { 44, 20, 473499 }, |
| { 45, 20, 473500 }, |
| { 46, 20, 473501 }, |
| { 47, 20, 473502 }, |
| { 48, 20, 473503 }, |
| { 99, 21, 0 } /* Shouldn't come this far */ |
| }; |
| |
| static int8_t rvlc_huffman_sf(bitfile *ld_sf, bitfile *ld_esc, |
| int8_t direction) |
| { |
| uint8_t i, j; |
| int8_t index; |
| uint32_t cw; |
| rvlc_huff_table *h = book_rvlc; |
| |
| i = h->len; |
| if (direction > 0) { |
| cw = faad_getbits(ld_sf, i DEBUGVAR(1, 0, "")); |
| } else { |
| cw = faad_getbits_rev(ld_sf, i DEBUGVAR(1, 0, "")); |
| } |
| |
| while ((cw != h->cw) |
| && (i < 10)) { |
| h++; |
| j = h->len - i; |
| i += j; |
| cw <<= j; |
| if (direction > 0) { |
| cw |= faad_getbits(ld_sf, j DEBUGVAR(1, 0, "")); |
| } else { |
| cw |= faad_getbits_rev(ld_sf, j DEBUGVAR(1, 0, "")); |
| } |
| } |
| |
| index = h->index; |
| |
| if (index == +ESC_VAL) { |
| int8_t esc = rvlc_huffman_esc(ld_esc, direction); |
| if (esc == 99) { |
| return 99; |
| } |
| index += esc; |
| #ifdef PRINT_RVLC |
| printf("esc: %d - ", esc); |
| #endif |
| } |
| if (index == -ESC_VAL) { |
| int8_t esc = rvlc_huffman_esc(ld_esc, direction); |
| if (esc == 99) { |
| return 99; |
| } |
| index -= esc; |
| #ifdef PRINT_RVLC |
| printf("esc: %d - ", esc); |
| #endif |
| } |
| |
| return index; |
| } |
| |
| static int8_t rvlc_huffman_esc(bitfile *ld, |
| int8_t direction) |
| { |
| uint8_t i, j; |
| uint32_t cw; |
| rvlc_huff_table *h = book_escape; |
| |
| i = h->len; |
| if (direction > 0) { |
| cw = faad_getbits(ld, i DEBUGVAR(1, 0, "")); |
| } else { |
| cw = faad_getbits_rev(ld, i DEBUGVAR(1, 0, "")); |
| } |
| |
| while ((cw != h->cw) |
| && (i < 21)) { |
| h++; |
| j = h->len - i; |
| i += j; |
| cw <<= j; |
| if (direction > 0) { |
| cw |= faad_getbits(ld, j DEBUGVAR(1, 0, "")); |
| } else { |
| cw |= faad_getbits_rev(ld, j DEBUGVAR(1, 0, "")); |
| } |
| } |
| |
| return h->index; |
| } |
| |
| #endif |
| |