mpc_decoder.c

这是著名的TCPMP播放器在WINDWOWS,和WINCE下编译通过的源程序.笔者对其中的LIBMAD库做了针对ARM MPU的优化. 并增加了词幕功能.

/*
  Copyright (c) 2005, The Musepack Development Team
  All rights reserved.

  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions are
  met:

  * Redistributions of source code must retain the above copyright
  notice, this list of conditions and the following disclaimer.

  * Redistributions in binary form must reproduce the above
  copyright notice, this list of conditions and the following
  disclaimer in the documentation and/or other materials provided
  with the distribution.

  * Neither the name of the The Musepack Development Team nor the
  names of its contributors may be used to endorse or promote
  products derived from this software without specific prior
  written permission.

  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

/// \file mpc_decoder.c
/// Core decoding routines and logic.

#include "musepack/musepack.h"
#include "musepack/internal.h"
#include "musepack/requant.h"
#include "musepack/huffman.h"

//------------------------------------------------------------------------------
// types
//------------------------------------------------------------------------------
enum
    {
        EQ_TAP = 13,                        // length of FIR filter for EQ
        DELAY = ((EQ_TAP + 1) / 2),         // delay of FIR
        FIR_BANDS = 4,                      // number of subbands to be FIR filtered
        MEMSIZE = MPC_DECODER_MEMSIZE,      // overall buffer size
        MEMSIZE2 = (MEMSIZE/2),             // size of one buffer
        MEMMASK = (MEMSIZE-1)
    };

//------------------------------------------------------------------------------
// forward declarations
//------------------------------------------------------------------------------
void mpc_decoder_init_huffman_sv6(mpc_decoder *d);
void mpc_decoder_init_huffman_sv7(mpc_decoder *d);
void mpc_decoder_read_bitstream_sv6(mpc_decoder *d);
void mpc_decoder_read_bitstream_sv7(mpc_decoder *d);
void mpc_decoder_update_buffer(mpc_decoder *d, mpc_uint32_t RING);
mpc_bool_t mpc_decoder_seek_sample(mpc_decoder *d, mpc_int64_t destsample);
void mpc_decoder_requantisierung(mpc_decoder *d, const mpc_int32_t Last_Band);

//------------------------------------------------------------------------------
// utility functions
//------------------------------------------------------------------------------
static mpc_int32_t f_read(mpc_decoder *d, void *ptr, size_t size) 
{ 
    return d->r->read(d->r->data, ptr, size); 
};

static mpc_bool_t f_seek(mpc_decoder *d, mpc_int32_t offset) 
{ 
    return d->r->seek(d->r->data, offset); 
};

static mpc_int32_t f_read_dword(mpc_decoder *d, mpc_uint32_t * ptr, mpc_uint32_t count) 
{
    count = f_read(d, ptr, count << 2) >> 2;
#ifndef MPC_LITTLE_ENDIAN
    mpc_uint32_t n;
    for(n = 0; n< count; n++) {
        ptr[n] = swap32(ptr[n]);
    }
#endif
    return count;
}

//------------------------------------------------------------------------------
// huffman & bitstream functions
//------------------------------------------------------------------------------
static const mpc_uint32_t mask [33] = {
    0x00000000, 0x00000001, 0x00000003, 0x00000007,
    0x0000000F, 0x0000001F, 0x0000003F, 0x0000007F,
    0x000000FF, 0x000001FF, 0x000003FF, 0x000007FF,
    0x00000FFF, 0x00001FFF, 0x00003FFF, 0x00007FFF,
    0x0000FFFF, 0x0001FFFF, 0x0003FFFF, 0x0007FFFF,
    0x000FFFFF, 0x001FFFFF, 0x003FFFFF, 0x007FFFFF,
    0x00FFFFFF, 0x01FFFFFF, 0x03FFFFFF, 0x07FFFFFF,
    0x0FFFFFFF, 0x1FFFFFFF, 0x3FFFFFFF, 0x7FFFFFFF,
    0xFFFFFFFF
};

/* F U N C T I O N S */

// resets bitstream decoding
static void
mpc_decoder_reset_bitstream_decode(mpc_decoder *d) 
{
    d->dword = 0;
    d->pos = 0;
    d->Zaehler = 0;
    d->WordsRead = 0;
}

// reports the number of read bits
static mpc_uint32_t
mpc_decoder_bits_read(mpc_decoder *d) 
{
    return 32 * d->WordsRead + d->pos;
}

// read desired number of bits out of the bitstream
static mpc_uint32_t
mpc_decoder_bitstream_read(mpc_decoder *d, const mpc_uint32_t bits) 
{
    mpc_uint32_t out = d->dword;

    d->pos += bits;

    if (d->pos < 32) {
        out >>= (32 - d->pos);
    }
    else {
        d->dword = d->Speicher[d->Zaehler = (d->Zaehler + 1) & MEMMASK];
        d->pos -= 32;
        if (d->pos) {
            out <<= d->pos;
            out |= d->dword >> (32 - d->pos);
        }
        ++(d->WordsRead);
    }

    return out & mask[bits];
}

// decode SCFI-bundle (sv4,5,6)
static void
mpc_decoder_scfi_bundle_read(
    mpc_decoder *d,
    HuffmanTyp* Table, mpc_int32_t* SCFI, mpc_int32_t* DSCF) 
{
    // load preview and decode
    mpc_uint32_t code  = d->dword << d->pos;
    if (d->pos > 26) {
        code |= d->Speicher[(d->Zaehler + 1) & MEMMASK] >> (32 - d->pos);
    }
    while (code < Table->Code) {
        Table++;
    }

    // set the new position within bitstream without performing a dummy-read
    if ((d->pos += Table->Length) >= 32) {
        d->pos -= 32;
        d->dword = d->Speicher[d->Zaehler = (d->Zaehler+1) & MEMMASK];
        ++(d->WordsRead);
    }

    *SCFI = Table->Value >> 1;
    *DSCF = Table->Value &  1;
}

static int __cdecl
mpc_decoder_huffman_typ_cmpfn(const void* p1, const void* p2)
{
    if (((HuffmanTyp*) p1)->Code < ((HuffmanTyp*) p2)->Code ) return +1;
    if (((HuffmanTyp*) p1)->Code > ((HuffmanTyp*) p2)->Code ) return -1;
    return 0;
}

// sort huffman-tables by codeword
// offset resulting value
void
mpc_decoder_resort_huff_tables(
    const mpc_uint32_t elements, HuffmanTyp* Table, const mpc_int32_t offset ) 
{
    mpc_uint32_t  i;

    for ( i = 0; i < elements; i++ ) {
        Table[i].Code <<= 32 - Table[i].Length;
        Table[i].Value  =  i - offset;
    }
    qsort(Table, elements, sizeof(*Table), mpc_decoder_huffman_typ_cmpfn);
}

// basic huffman decoding routine
// works with maximum lengths up to 14
static mpc_int32_t
mpc_decoder_huffman_decode(mpc_decoder *d, const HuffmanTyp *Table) 
{
    // load preview and decode
    mpc_uint32_t code = d->dword << d->pos;
    if (d->pos > 18) {
        code |= d->Speicher[(d->Zaehler + 1) & MEMMASK] >> (32 - d->pos);
    }
    while (code < Table->Code) {
        Table++;
    }

    // set the new position within bitstream without performing a dummy-read
    if ((d->pos += Table->Length) >= 32) {
        d->pos -= 32;
        d->dword = d->Speicher[d->Zaehler = (d->Zaehler + 1) & MEMMASK];
        ++(d->WordsRead);
    }

    return Table->Value;
}

// faster huffman through previewing less bits
// works with maximum lengths up to 10
static mpc_int32_t
mpc_decoder_huffman_decode_fast(mpc_decoder *d, const HuffmanTyp* Table)
{
    // load preview and decode
    mpc_uint32_t code  = d->dword << d->pos;
    if (d->pos > 22) {
        code |= d->Speicher[(d->Zaehler + 1) & MEMMASK] >> (32 - d->pos);
    }
    while (code < Table->Code) {
        Table++;
    }

    // set the new position within bitstream without performing a dummy-read
    if ((d->pos += Table->Length) >= 32) {
        d->pos -= 32;
        d->dword = d->Speicher[d->Zaehler = (d->Zaehler + 1) & MEMMASK];
        ++(d->WordsRead);
    }

    return Table->Value;
}

// even faster huffman through previewing even less bits
// works with maximum lengths up to 5
static mpc_int32_t
mpc_decoder_huffman_decode_faster(mpc_decoder *d, const HuffmanTyp* Table)
{
    // load preview and decode
    mpc_uint32_t code  = d->dword << d->pos;
    if (d->pos > 27) {
        code |= d->Speicher[(d->Zaehler + 1) & MEMMASK] >> (32 - d->pos);
    }
    while (code < Table->Code) {
        Table++;
    }

    // set the new position within bitstream without performing a dummy-read
    if ((d->pos += Table->Length) >= 32) {
        d->pos -= 32;
        d->dword = d->Speicher[d->Zaehler = (d->Zaehler + 1) & MEMMASK];
        ++(d->WordsRead);
    }

    return Table->Value;
}

static void
mpc_decoder_reset_v(mpc_decoder *d) 
{
    memset(d->V_L, 0, sizeof d->V_L);
    memset(d->V_R, 0, sizeof d->V_R);
}

static void
mpc_decoder_reset_synthesis(mpc_decoder *d) 
{
    mpc_decoder_reset_v(d);
}

static void
mpc_decoder_reset_y(mpc_decoder *d) 
{
    memset(d->Y_L, 0, sizeof d->Y_L);
    memset(d->Y_R, 0, sizeof d->Y_R);
}

static void
mpc_decoder_reset_globals(mpc_decoder *d) 
{
    mpc_decoder_reset_bitstream_decode(d);

    d->DecodedFrames  = 0;
    d->StreamVersion  = 0;
    d->MS_used        = 0;

    memset(d->Y_L          , 0, sizeof d->Y_L           );
    memset(d->Y_R          , 0, sizeof d->Y_R           );
    memset(d->SCF_Index_L     , 0, sizeof d->SCF_Index_L      );
    memset(d->SCF_Index_R     , 0, sizeof d->SCF_Index_R      );
    memset(d->Res_L           , 0, sizeof d->Res_L            );
    memset(d->Res_R           , 0, sizeof d->Res_R            );
    memset(d->SCFI_L          , 0, sizeof d->SCFI_L           );
    memset(d->SCFI_R          , 0, sizeof d->SCFI_R           );
    memset(d->DSCF_Flag_L     , 0, sizeof d->DSCF_Flag_L      );
    memset(d->DSCF_Flag_R     , 0, sizeof d->DSCF_Flag_R      );
    memset(d->DSCF_Reference_L, 0, sizeof d->DSCF_Reference_L );
    memset(d->DSCF_Reference_R, 0, sizeof d->DSCF_Reference_R );
    memset(d->Q               , 0, sizeof d->Q                );
    memset(d->MS_Flag         , 0, sizeof d->MS_Flag          );
}

static mpc_uint32_t
mpc_decoder_decode_internal(mpc_decoder *d, MPC_SAMPLE_FORMAT *buffer) 
{
    mpc_uint32_t output_frame_length = MPC_FRAME_LENGTH;

    mpc_uint32_t  FrameBitCnt = 0;

    if (d->DecodedFrames >= d->OverallFrames) {
        return (mpc_uint32_t)(-1);                           // end of file -> abort decoding
    }

    // read jump-info for validity check of frame
    d->FwdJumpInfo  = mpc_decoder_bitstream_read(d, 20);
	if (d->SeekTable)
		d->SeekTable[d->DecodedFrames] = 20 + d->FwdJumpInfo; // Picard 2005.04.29

    d->ActDecodePos = (d->Zaehler << 5) + d->pos;

    // decode data and check for validity of frame
    FrameBitCnt = mpc_decoder_bits_read(d);
    switch (d->StreamVersion) {
    case 0x04:
    case 0x05:
    case 0x06:
        mpc_decoder_read_bitstream_sv6(d);
        break;
    case 0x07:
    case 0x17: