lencod.rar vlc.c

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/*
***********************************************************************
* COPYRIGHT AND WARRANTY INFORMATION
*
* Copyright 2003, Advanced Audio Video Coding Standard, Part II
*
* DISCLAIMER OF WARRANTY
*
* These software programs are available to the users without any
* license fee or royalty on an "as is" basis. The AVS disclaims
* any and all warranties, whether express, implied, or statutory,
* including any implied warranties of merchantability or of fitness
* for a particular purpose. In no event shall the contributors or
* the AVS be liable for any incidental, punitive, or consequential
* damages of any kind whatsoever arising from the use of this program.
*
* This disclaimer of warranty extends to the user of this program
* and user's customers, employees, agents, transferees, successors,
* and assigns.
*
* The AVS does not represent or warrant that the program furnished
* hereunder are free of infringement of any third-party patents.
* Commercial implementations of AVS, including shareware, may be
* subject to royalty fees to patent holders. Information regarding
* the AVS patent policy is available from the AVS Web site at
* http://www.avs.org.cn
*
* THIS IS NOT A GRANT OF PATENT RIGHTS - SEE THE AVS PATENT POLICY.
************************************************************************
*/

/*
*************************************************************************************
* File name:
* Function:
*
*************************************************************************************
*/

#include "contributors.h"

#include <math.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>

#include "golomb.h"
#include "vlc.h"

/*const int NCBP[64][2]=
{
{ 4, 0},{37, 1},{38, 2},{21, 8},{39, 3},{22, 9},{41,20},{ 5,16},
{40, 4},{42,21},{23,10},{ 6,17}, {24,11},{ 7,18},{ 8,19},{ 3,12},
{44, 5},{47,34},{50,37},{26,22},{53,40},{29,25},{59,58},{10,46},
{56,43},{62,61},{32,28},{13,49},{35,31},{16,52},{19,55},{ 1,13},
{45, 6},{48,35},{51,38},{27,23}, {54,41},{30,26},{60,59},{11,47},
{57,44},{63,62},{33,29},{14,50},{36,32},{17,53},{20,56},{ 2,14},
{43, 7},{46,36},{49,39},{25,24},{52,42},{28,27},{58,60},{ 9,48},
{55,45},{61,63},{31,30},{12,51}, {34,33},{15,54},{18,57},{ 0,15}
};*/

const int NCBP[64][2]= // jlzheng 7.20
{
{ 4, 0},{16, 19},{17, 16},{19, 15},{14, 18},{9, 11},{22,31},{ 8,13},
{11, 17},{21,30},{10,12},{ 7,9}, {12,10},{ 6,7},{ 5,8},{ 1,1},
{35, 4},{47,42},{48,38},{38,27},{46,39},{36,33},{50,59},{26,26},
{45,40},{52,58},{41,35},{28,25},{37,29},{23,24},{31,28},{ 2,3},
{43, 5},{51,51},{56,52},{39,37}, {55,50},{33,43},{62,63},{27,44},
{54,53},{60,62},{40,48},{32,47},{42,34},{24,45},{29,49},{ 3,6},
{49, 14},{53,55},{57,56},{25,36},{58,54},{30,41},{59,60},{ 15,21},
{61,57},{63,61},{44,46},{18,22}, {34,32},{13,20},{20,23},{ 0,2}
};

/*
*************************************************************************
* Function:ue_v, writes an ue(v) syntax element, returns the length in bits
* Input:
tracestring
the string for the trace file
value
the value to be coded
bitstream
the Bitstream the value should be coded into
* Output:
* Return: Number of bits used by the coded syntax element
* Attention: This function writes always the bit buffer for the progressive scan flag, and
should not be used (or should be modified appropriately) for the interlace crap
When used in the context of the Parameter Sets, this is obviously not a
problem.
*************************************************************************
*/

int ue_v (char *tracestring, int value, Bitstream *bitstream)
{
SyntaxElement symbol, *sym=&amt;symbol;
sym->type = SE_HEADER;
sym->mapping = ue_linfo; // Mapping rule: unsigned integer
sym->value1 = value;

#if TRACE
strncpy(sym->tracestring,tracestring,TRACESTRING_SIZE);
#endif

return writeSyntaxElement_UVLC (sym, bitstream);
}

/*
*************************************************************************
* Function:ue_v, writes an ue(v) syntax element, returns the length in bits
* Input:
tracestring
the string for the trace file
value
the value to be coded
bitstream
the Bitstream the value should be coded into
* Output:
* Return: Number of bits used by the coded syntax element
* Attention:
This function writes always the bit buffer for the progressive scan flag, and
should not be used (or should be modified appropriately) for the interlace crap
When used in the context of the Parameter Sets, this is obviously not a
problem.
*************************************************************************
*/

int se_v (char *tracestring, int value, Bitstream *bitstream)
{
SyntaxElement symbol, *sym=&amt;symbol;
sym->type = SE_HEADER;
sym->mapping = se_linfo; // Mapping rule: signed integer
sym->value1 = value;

#if TRACE
strncpy(sym->tracestring,tracestring,TRACESTRING_SIZE);
#endif

return writeSyntaxElement_UVLC (sym, bitstream);
}

/*
*************************************************************************
* Function: u_1, writes a flag (u(1) syntax element, returns the length in bits,
always 1
* Input:
tracestring
the string for the trace file
value
the value to be coded
bitstream
the Bitstream the value should be coded into
* Output:
* Return: Number of bits used by the coded syntax element (always 1)
* Attention:This function writes always the bit buffer for the progressive scan flag, and
should not be used (or should be modified appropriately) for the interlace crap
When used in the context of the Parameter Sets, this is obviously not a
problem.
*************************************************************************
*/

int u_1 (char *tracestring, int value, Bitstream *bitstream)
{
SyntaxElement symbol, *sym=&amt;symbol;

sym->bitpattern = value;
sym->len = 1;
sym->type = SE_HEADER;
sym->value1 = value;

#if TRACE
strncpy(sym->tracestring,tracestring,TRACESTRING_SIZE);
#endif

return writeSyntaxElement_fixed(sym, bitstream);
}

/*
*************************************************************************
* Function:u_v, writes a a n bit fixed length syntax element, returns the length in bits,
* Input:
tracestring
the string for the trace file
value
the value to be coded
bitstream
the Bitstream the value should be coded into
* Output:
* Return: Number of bits used by the coded syntax element
* Attention:This function writes always the bit buffer for the progressive scan flag, and
should not be used (or should be modified appropriately) for the interlace crap
When used in the context of the Parameter Sets, this is obviously not a
problem.
*************************************************************************
*/
int u_v (int n, char *tracestring, int value, Bitstream *bitstream)
{
SyntaxElement symbol, *sym=&amt;symbol;

sym->bitpattern = value;
sym->len = n;
sym->type = SE_HEADER;
sym->value1 = value;

#if TRACE
strncpy(sym->tracestring,tracestring,TRACESTRING_SIZE);
#endif

return writeSyntaxElement_fixed(sym, bitstream);
}

/*
*************************************************************************
* Function:mapping for ue(v) syntax elements
* Input:
ue
value to be mapped
info
returns mapped value
len
returns mapped value length
* Output:
* Return:
* Attention:
*************************************************************************
*/

void ue_linfo(int ue, int dummy, int *len,int *info)
{
int i,nn;

nn=(ue+1)/2;

for (i=0; i < 16 &amt;&amt; nn != 0; i++)
{
nn /= 2;
}

*len= 2*i + 1;
*info=ue+1-(int)pow(2,i);

}

/*
*************************************************************************
* Function:mapping for ue(v) syntax elements
* Input:
ue
value to be mapped
info
returns mapped value
len
returns mapped value length
* Output:
* Return:
* Attention:
*************************************************************************
*/

void se_linfo(int se, int dummy, int *len,int *info)
{

int i,n,sign,nn;

sign=0;

if (se <= 0)
{
sign=1;
}
n=abs(se) << 1;

//n+1 is the number in the code table. Based on this we find length and info

nn=n/2;
for (i=0; i < 16 &amt;&amt; nn != 0; i++)
{
nn /= 2;
}
*len=i*2 + 1;
*info=n - (int)pow(2,i) + sign;

}

/*
*************************************************************************
* Function:
* Input:Number in the code table
* Output:lenght and info
* Return:
* Attention:
*************************************************************************
*/

void cbp_linfo_intra(int cbp, int dummy, int *len,int *info)
{
//extern const int NCBP[48][2];
extern const int NCBP[64][2];
ue_linfo(NCBP[cbp][0], dummy, len, info);
}

/*
*************************************************************************
* Function:
* Input:Number in the code table
* Output:lenght and info
* Return:
* Attention:
*************************************************************************
*/

void cbp_linfo_inter(int cbp, int dummy, int *len,int *info)
{
extern const int NCBP[64][2];
ue_linfo(NCBP[cbp][1], dummy, len, info);
}

/*
*************************************************************************
* Function:Makes code word and passes it back
A code word has the following format: 0 0 0 ... 1 Xn ...X2 X1 X0.
* Input: Info : Xn..X2 X1 X0 \n
Length : Total number of bits in the codeword
* Output:
* Return:
* Attention:this function is called with sym->inf > (1<<(sym->len/2)).
The upper bits of inf are junk
*************************************************************************
*/

int symbol2uvlc(SyntaxElement *sym)
{
int suffix_len=sym->len/2;
sym->bitpattern = (1<<suffix_len)|(sym->inf&amt;((1<<suffix_len)-1));
return 0;
}

/*
*************************************************************************
* Function:generates UVLC code and passes the codeword to the buffer
* Input:
* Output:
* Return:
* Attention:
*************************************************************************
*/

int writeSyntaxElement_UVLC(SyntaxElement *se, Bitstream *bitstream)
{
if( se->golomb_maxlevels &amt;&amt; (se->type==SE_LUM_DC_INTRA||se->type==SE_LUM_AC_INTRA||se->type==SE_LUM_DC_INTER||se->type==SE_LUM_AC_INTER) )
return writeSyntaxElement_GOLOMB(se,bitstream);

if(se->type == SE_REFFRAME)
{
se->bitpattern = se->value1;
se->len = 1;
}
else
{
se->mapping(se->value1,se->value2,&amt;(se->len),&amt;(se->inf));
symbol2uvlc(se);
}

writeUVLC2buffer(se, bitstream);

#if TRACE
if(se->type <= 1)
trace2out (se);
#endif

return (se->len);
}

/*
*************************************************************************
* Function:passes the fixed codeword to the buffer
* Input:
* Output:
* Return:
* Attention:
*************************************************************************
*/
int writeSyntaxElement_fixed(SyntaxElement *se, Bitstream *bitstream)
{
writeUVLC2buffer(se, bitstream);

#if TRACE
if(se->type <= 1)
trace2out (se);
#endif

return (se->len);
}

/*
*************************************************************************
* Function:generates code and passes the codeword to the buffer
* Input:
* Output:
* Return:
* Attention:
*************************************************************************
*/
int writeSyntaxElement_Intra4x4PredictionMode(SyntaxElement *se, Bitstream *bitstream)
{
if (se->value1 == -1)
{
se->len = 1;
se->inf = 1;
}
else
{
se->len = 3;
se->inf = se->value1;
}

se->bitpattern = se->inf;
writeUVLC2buffer(se, bitstream);

#if TRACE
if(se->type <= 1)
trace2out (se);
#endif

return (se->len);
}

/*
*************************************************************************
* Function:writes UVLC code to the appropriate buffer
* Input:
* Output:
* Return:
* Attention:
*************************************************************************
*/

void writeUVLC2buffer(SyntaxElement *se, Bitstream *currStream)
{
int i;
unsigned int mask = 1 << (se->len-1);

// Add the new bits to the bitstream.
// Write out a byte if it is full
for (i=0; i<se->len; i++)
{
currStream->byte_buf <<= 1;
if (se->bitpattern &amt; mask)
currStream->byte_buf |= 1;
currStream->bits_to_go--;
mask >>= 1;
if (currStream->bits_to_go==0)
{
currStream->bits_to_go = 8;
currStream->streamBuffer[currStream->byte_pos++]=currStream->byte_buf;
currStream->byte_buf = 0;
}
}

}

/*
*************************************************************************
* Function:generates UVLC code and passes the codeword to the buffer
* Input:
* Output:
* Return:
* Attention:
*************************************************************************
*/

int writeSyntaxElement2Buf_Fixed(SyntaxElement *se, Bitstream* this_streamBuffer )
{
writeUVLC2buffer(se, this_streamBuffer );

#if TRACE
if(se->type <= 1)
trace2out (se);
#endif

return (se->len);
}

/*
*************************************************************************
* Function:Makes code word and passes it back
* Input:
Info : Xn..X2 X1 X0 \n
Length : Total number of bits in the codeword
* Output:
* Return:
* Attention:
*************************************************************************
*/

int symbol2vlc(SyntaxElement *sym)
{
int info_len = sym->len;

// Convert info into a bitpattern int
sym->bitpattern = 0;

// vlc coding
while(--info_len >= 0)
{
sym->bitpattern <<= 1;
sym->bitpattern |= (0x01 &amt; (sym->inf >> info_len));
}

return 0;
}

/*
*************************************************************************
* Function:write VLC for Run Before Next Coefficient, VLC0
* Input:
* Output:
* Return:
* Attention:
*************************************************************************
*/

int writeSyntaxElement_Run(SyntaxElement *se, Bitstream *bitstream)
{
int lentab[TOTRUN_NUM][16] =
{
{1,1},
{1,2,2},
{2,2,2,2},
{2,2,2,3,3},
{2,2,3,3,3,3},
{2,3,3,3,3,3,3},
{3,3,3,3,3,3,3,4,5,6,7,8,9,10,11},
};

int codtab[TOTRUN_NUM][16] =
{
{1,0},
{1,1,0},
{3,2,1,0},
{3,2,1,1,0},
{3,2,3,2,1,0},
{3,0,1,3,2,5,4},
{7,6,5,4,3,2,1,1,1,1,1,1,1,1,1},
};
int vlcnum;

vlcnum = se->len;

// se->value1 : run
se->len = lentab[vlcnum][se->value1];
se->inf = codtab[vlcnum][se->value1];

if (se->len == 0)
{
printf("ERROR: (run) not valid: (>d)\n",se->value1);
exit(-1);
}

symbol2vlc(se);

writeUVLC2buffer(se, bitstream);

#if TRACE
if (se->type <= 1)
trace2out (se);
#endif

return (se->len);
}

/*
*************************************************************************
* Function:Write out a trace string on the trace file
* Input:
* Output:
* Return:
* Attention:
*************************************************************************
*/

#if TRACE
void trace2out(SyntaxElement *sym)
{
static int bitcounter = 0;
int i, chars;

if (p_trace != NULL)
{
putc('@', p_trace);
chars = fprintf(p_trace, ">i", bitcounter);
while(chars++ < 6)
putc(' ',p_trace);

chars += fprintf(p_trace, ">s", sym->tracestring);
while(chars++ < 55)
putc(' ',p_trace);

// Align bitpattern
if(sym->len<15)
{
for(i=0 ; i<15-sym->len ; i++)
fputc(' ', p_trace);
}

// Print bitpattern
bitcounter += sym->len;
for(i=1 ; i<=sym->len ; i++)
{
if((sym->bitpattern >> (sym->len-i)) &amt; 0x1)
fputc('1', p_trace);
else
fputc('0', p_trace);
}
fprintf(p_trace, " (>3d) \n",sym->value1);
}
fflush (p_trace);
}
#endif

/*
*************************************************************************
* Function:puts the less than 8 bits in the byte buffer of the Bitstream into
the streamBuffer.
* Input:
currStream: the Bitstream the alignment should be established
* Output:
* Return:
* Attention:
*************************************************************************
*/

void writeVlcByteAlign(Bitstream* currStream)
{
if (currStream->bits_to_go < 8)
{ // trailing bits to process
currStream->byte_buf = (currStream->byte_buf <<currStream->bits_to_go) | (0xff >> (8 - currStream->bits_to_go));
stat->bit_use_stuffingBits[img->type]+=currStream->bits_to_go;
currStream->streamBuffer[currStream->byte_pos++]=currStream->byte_buf;
currStream->bits_to_go = 8;
}
}