diff options
Diffstat (limited to 'faad2/src/libfaad/rvlc.c')
| -rw-r--r-- | faad2/src/libfaad/rvlc.c | 533 |
1 files changed, 533 insertions, 0 deletions
diff --git a/faad2/src/libfaad/rvlc.c b/faad2/src/libfaad/rvlc.c new file mode 100644 index 0000000..3ce25ec --- /dev/null +++ b/faad2/src/libfaad/rvlc.c @@ -0,0 +1,533 @@ +/*
+** 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 "common.h"
+#include "structs.h"
+
+#include <stdlib.h>
+
+#include "syntax.h"
+#include "bits.h"
+#include "rvlc.h"
+
+
+#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;
+// 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
+
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