/*
- * AC3 and E-AC3 decoder tables
+ * AC-3 and E-AC-3 decoder tables
* Copyright (c) 2007 Bartlomiej Wolowiec <bartek.wolowiec@gmail.com>
*
* This file is part of FFmpeg.
*/
/**
- * @file ac3dec_data.c
- * tables taken directly from AC3 spec.
+ * @file libavcodec/ac3dec_data.c
+ * tables taken directly from the AC-3 spec.
*/
#include "ac3dec_data.h"
#include "ac3.h"
+/**
+ * table used to ungroup 3 values stored in 5 bits.
+ * used by bap=1 mantissas and GAQ.
+ * ff_ac3_ungroup_3_in_5_bits_tab[i] = { i/9, (i%9)/3, (i%9)%3 }
+ */
+const uint8_t ff_ac3_ungroup_3_in_5_bits_tab[32][3] = {
+ { 0, 0, 0 }, { 0, 0, 1 }, { 0, 0, 2 }, { 0, 1, 0 },
+ { 0, 1, 1 }, { 0, 1, 2 }, { 0, 2, 0 }, { 0, 2, 1 },
+ { 0, 2, 2 }, { 1, 0, 0 }, { 1, 0, 1 }, { 1, 0, 2 },
+ { 1, 1, 0 }, { 1, 1, 1 }, { 1, 1, 2 }, { 1, 2, 0 },
+ { 1, 2, 1 }, { 1, 2, 2 }, { 2, 0, 0 }, { 2, 0, 1 },
+ { 2, 0, 2 }, { 2, 1, 0 }, { 2, 1, 1 }, { 2, 1, 2 },
+ { 2, 2, 0 }, { 2, 2, 1 }, { 2, 2, 2 }, { 3, 0, 0 },
+ { 3, 0, 1 }, { 3, 0, 2 }, { 3, 1, 0 }, { 3, 1, 1 }
+};
+
const uint8_t ff_eac3_hebap_tab[64] = {
0, 1, 2, 3, 4, 5, 6, 7, 8, 8,
8, 8, 9, 9, 9, 10, 10, 10, 10, 11,
/**
* Table E3.6, Gk=2 & Gk=4, B
* Large mantissa inverse quantization, negative mantissa remapping offsets
+ * Table values from the spec are right-shifted by 8 to simplify calculations.
* ff_eac3_gaq_remap_3_4_b[hebap-8][Gk=2,4]
*/
-const int16_t ff_eac3_gaq_remap_2_4_b[9][2] = {
- { -5461, -1170},
- { -11703, -4915},
- { -14199, -6606},
- { -15327, -7412},
- { -15864, -7805},
- { -16126, -7999},
- { -16255, -8096},
- { -16320, -8144},
- { -16352, -8168}
+const int8_t ff_eac3_gaq_remap_2_4_b[9][2] = {
+ { -22, -5 },
+ { -46, -20 },
+ { -56, -26 },
+ { -60, -29 },
+ { -62, -31 },
+ { -63, -32 },
+ { -64, -32 },
+ { -64, -32 },
+ { -64, -32 },
};
static const int16_t vq_hebap1[4][6] = {
{ 3231, -3284, 27336, 4174, -1683, 497},
};
-const int16_t (*ff_eac3_vq_hebap[8])[6] = {
+const int16_t (* const ff_eac3_mantissa_vq[8])[6] = {
NULL,
vq_hebap1,
vq_hebap2,
*/
const uint8_t ff_eac3_default_cpl_band_struct[18] =
{ 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1 };
+
+/**
+ * Table of bin locations for rematrixing bands
+ * reference: Section 7.5.2 Rematrixing : Frequency Band Definitions
+ */
+const uint8_t ff_ac3_rematrix_band_tab[5] = { 13, 25, 37, 61, 253 };