bsdec-vlc.h

Go to the documentation of this file.

// GENERATED by bsdec/gentable.py - do not edit.
//
// Sony's standard MDEC AC code book (FileFormat47 Table 1-7), rearranged for a
// count-leading-zeros dispatch. Every code in the book is N zeros, a marker 1, then a
// suffix whose width depends only on N, so one clz plus one indexed load replaces the
// bit-at-a-time walk down a trie.
//
//   n     codes  code lengths  suffix width
//   0     3      [2, 3]        2
//   1     6      [4, 5]        3
//   2     22     [6, 9]        6
//   3     8      [7]           3
//   4     8      [8]           3
//   5     1      [6]           0
//   6     16     [11]          4
//   7     32     [13]          5
//   8     32     [14]          5
//   9     32     [15]          5
//   10    32     [16]          5
//   11    32     [17]          5
//
// 224 symbols, 269 table slots, 0 unreachable (invalid prefixes).
//
// Entry layout, chosen so the common path is one load and one mask:
//   bits  0..15  the MDEC run-level halfword, ready to store (0xfe00 for EOB)
//   bits 16..20  suffix bits to consume after the marker 1
//   bits 21..22  kind: 0 normal, 1 end of block, 2 escape
//   bit  23      set on a valid entry; a zero word is an invalid prefix
 
#pragma once
 
#include <stdint.h>
 
#define BSDEC_VLC_MAXNZ 11
 
#define BSDEC_VLC_HALFWORD(e) ((uint16_t)((e) & 0xffff))
#define BSDEC_VLC_SUFFIXBITS(e) (((e) >> 16) & 0x1f)
#define BSDEC_VLC_KIND(e) (((e) >> 21) & 3)
#define BSDEC_VLC_VALID(e) ((e) & (1 << 23))
 
#define BSDEC_VLC_NORMAL 0
#define BSDEC_VLC_EOB 1
#define BSDEC_VLC_ESCAPE 2
 
/* Rows past 11 are the garbage-prefix sentinel: width 0, pointing at
   the appended EOB slot, so an impossible prefix needs no bounds test. */
static const uint8_t c_bsdecVlcSuffixBits[32] = {2, 3, 6, 3, 3, 0, 4, 5, 5, 5, 5, 5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
 
static const uint16_t c_bsdecVlcOffset[32] = {0, 4, 12, 76, 84, 92, 93, 109, 141, 173, 205, 237, 269, 269, 269, 269, 269, 269, 269, 269, 269, 269, 269, 269, 269, 269, 269, 269, 269, 269, 269, 269};
 
static const uint32_t c_bsdecVlc[270] = {
    // n = 0, suffix 2 bits
    0x00a1fe00, 0x00a1fe00, 0x00820001, 0x008203ff,
    // n = 1, suffix 3 bits
    0x00830002, 0x008303fe, 0x00830801, 0x00830bff, 0x00820401, 0x00820401, 0x008207ff, 0x008207ff,
    // n = 2, suffix 6 bits
    0x00863401, 0x008637ff, 0x00860006, 0x008603fa, 0x00863001, 0x008633ff, 0x00862c01, 0x00862fff, 0x00860c02,
    0x00860ffe, 0x00860403, 0x008607fd, 0x00860005, 0x008603fb, 0x00862801, 0x00862bff, 0x00830003, 0x00830003,
    0x00830003, 0x00830003, 0x00830003, 0x00830003, 0x00830003, 0x00830003, 0x008303fd, 0x008303fd, 0x008303fd,
    0x008303fd, 0x008303fd, 0x008303fd, 0x008303fd, 0x008303fd, 0x00831001, 0x00831001, 0x00831001, 0x00831001,
    0x00831001, 0x00831001, 0x00831001, 0x00831001, 0x008313ff, 0x008313ff, 0x008313ff, 0x008313ff, 0x008313ff,
    0x008313ff, 0x008313ff, 0x008313ff, 0x00830c01, 0x00830c01, 0x00830c01, 0x00830c01, 0x00830c01, 0x00830c01,
    0x00830c01, 0x00830c01, 0x00830fff, 0x00830fff, 0x00830fff, 0x00830fff, 0x00830fff, 0x00830fff, 0x00830fff,
    0x00830fff,
    // n = 3, suffix 3 bits
    0x00831c01, 0x00831fff, 0x00831801, 0x00831bff, 0x00830402, 0x008307fe, 0x00831401, 0x008317ff,
    // n = 4, suffix 3 bits
    0x00830802, 0x00830bfe, 0x00832401, 0x008327ff, 0x00830004, 0x008303fc, 0x00832001, 0x008323ff,
    // n = 5, suffix 0 bits
    0x00c00000,
    // n = 6, suffix 4 bits
    0x00844001, 0x008443ff, 0x00841402, 0x008417fe, 0x00840007, 0x008403f9, 0x00840803, 0x00840bfd, 0x00840404,
    0x008407fc, 0x00843c01, 0x00843fff, 0x00843801, 0x00843bff, 0x00841002, 0x008413fe,
    // n = 7, suffix 5 bits
    0x0085000b, 0x008503f5, 0x00852002, 0x008523fe, 0x00851003, 0x008513fd, 0x0085000a, 0x008503f6, 0x00850804,
    0x00850bfc, 0x00851c02, 0x00851ffe, 0x00855401, 0x008557ff, 0x00855001, 0x008553ff, 0x00850009, 0x008503f7,
    0x00854c01, 0x00854fff, 0x00854801, 0x00854bff, 0x00850405, 0x008507fb, 0x00850c03, 0x00850ffd, 0x00850008,
    0x008503f8, 0x00851802, 0x00851bfe, 0x00854401, 0x008547ff,
    // n = 8, suffix 5 bits
    0x00852802, 0x00852bfe, 0x00852402, 0x008527fe, 0x00851403, 0x008517fd, 0x00850c04, 0x00850ffc, 0x00850805,
    0x00850bfb, 0x00850407, 0x008507f9, 0x00850406, 0x008507fa, 0x0085000f, 0x008503f1, 0x0085000e, 0x008503f2,
    0x0085000d, 0x008503f3, 0x0085000c, 0x008503f4, 0x00856801, 0x00856bff, 0x00856401, 0x008567ff, 0x00856001,
    0x008563ff, 0x00855c01, 0x00855fff, 0x00855801, 0x00855bff,
    // n = 9, suffix 5 bits
    0x0085001f, 0x008503e1, 0x0085001e, 0x008503e2, 0x0085001d, 0x008503e3, 0x0085001c, 0x008503e4, 0x0085001b,
    0x008503e5, 0x0085001a, 0x008503e6, 0x00850019, 0x008503e7, 0x00850018, 0x008503e8, 0x00850017, 0x008503e9,
    0x00850016, 0x008503ea, 0x00850015, 0x008503eb, 0x00850014, 0x008503ec, 0x00850013, 0x008503ed, 0x00850012,
    0x008503ee, 0x00850011, 0x008503ef, 0x00850010, 0x008503f0,
    // n = 10, suffix 5 bits
    0x00850028, 0x008503d8, 0x00850027, 0x008503d9, 0x00850026, 0x008503da, 0x00850025, 0x008503db, 0x00850024,
    0x008503dc, 0x00850023, 0x008503dd, 0x00850022, 0x008503de, 0x00850021, 0x008503df, 0x00850020, 0x008503e0,
    0x0085040e, 0x008507f2, 0x0085040d, 0x008507f3, 0x0085040c, 0x008507f4, 0x0085040b, 0x008507f5, 0x0085040a,
    0x008507f6, 0x00850409, 0x008507f7, 0x00850408, 0x008507f8,
    // n = 11, suffix 5 bits
    0x00850412, 0x008507ee, 0x00850411, 0x008507ef, 0x00850410, 0x008507f0, 0x0085040f, 0x008507f1, 0x00851803,
    0x00851bfd, 0x00854002, 0x008543fe, 0x00853c02, 0x00853ffe, 0x00853802, 0x00853bfe, 0x00853402, 0x008537fe,
    0x00853002, 0x008533fe, 0x00852c02, 0x00852ffe, 0x00857c01, 0x00857fff, 0x00857801, 0x00857bff, 0x00857401,
    0x008577ff, 0x00857001, 0x008573ff, 0x00856c01, 0x00856fff,
    // sentinel: every prefix longer than the book ends the block here
    0x00a0fe00,
};
 
// Version-3 delta-DC size books, indexed by size 0..8: MPEG-1's DC size codes
// (ISO/IEC 11172-2 tables B-12 and B-13). Blocks 0 and 1 of a macroblock are Cr and
// Cb and take the chroma book; blocks 2..5 are luma and share the other one. Both
// are prefix-free, checked at generation time, so a linear walk resolves them
// without caring about the order.
static const uint8_t c_bsdecDcLumaCode[9] = {0x04, 0x00, 0x01, 0x05, 0x06, 0x0e, 0x1e, 0x3e, 0x7e};
static const uint8_t c_bsdecDcLumaBits[9] = {3, 2, 2, 3, 3, 4, 5, 6, 7};
static const uint8_t c_bsdecDcChromaCode[9] = {0x00, 0x01, 0x02, 0x06, 0x0e, 0x1e, 0x3e, 0x7e, 0xfe};
static const uint8_t c_bsdecDcChromaBits[9] = {2, 2, 2, 3, 4, 5, 6, 7, 8};