mpeg2coder.cc

来自「Motion JPEG编解码器源代码」· CC 代码 · 共 874 行 · 第 1/2 页

	if (len!=0) /* a VLC code exists */
	{
		PutBits(ptab->code,len);
		PutBits(signed_level<0,1); /* sign */
	}
	else
	{
		/* no VLC for this (run, level) combination: use escape coding (7.2.2.3) */
		PutBits(1l,6); /* Escape */
		PutBits(run,6); /* 6 bit code for run */
		if (encparams.mpeg1)
		{
			/* ISO/IEC 11172-2 uses a 8 or 16 bit code */
			if (signed_level>127)
				PutBits(0,8);
			if (signed_level<-127)
				PutBits(128,8);
			PutBits(signed_level,8);
		}
		else
		{
			/* ISO/IEC 13818-2 uses a 12 bit code, Table B-16 */
			PutBits(signed_level,12);
		}
	}
}

/* generate variable length code for other DCT coefficients (7.2.2) */
int MPEG2CodingBuf::AC_bits(int run, int signed_level, int vlcformat)
{
	int level;
	const VLCtable *ptab;

	level = abs(signed_level);

	if (run<2 && level<41)
	{
		/* vlcformat selects either of Table B-14 / B-15 */
		if (vlcformat)
			ptab = &dct_code_tab1a[run][level-1];
		else
			ptab = &dct_code_tab1[run][level-1];

		return ptab->len+1;
	}
	else if (run<32 && level<6)
	{
		/* vlcformat selects either of Table B-14 / B-15 */
		if (vlcformat)
			ptab = &dct_code_tab2a[run-2][level-1];
		else
			ptab = &dct_code_tab2[run-2][level-1];

		return ptab->len+1;
	}
	else
	{
		return 12+12;
	}
}

/* generate variable length code for macroblock_address_increment (6.3.16) */
void MPEG2CodingBuf::PutAddrInc(int addrinc)
{
	while (addrinc>33)
	{
		PutBits(0x08,11); /* macroblock_escape */
		addrinc-= 33;
	}
	assert( addrinc >= 1 && addrinc <= 33 );
	PutBits(addrinctab[addrinc-1].code,addrinctab[addrinc-1].len);
}

int MPEG2CodingBuf::AddrInc_bits(int addrinc)
{
	int bits = 0;
	while (addrinc>33)
	{
		bits += 11;
		addrinc-= 33;
	}
	return bits + addrinctab[addrinc-1].len;
}

/* generate variable length code for macroblock_type (6.3.16.1) */
void MPEG2CodingBuf::PutMBType(int pict_type, int mb_type)
{
	PutBits(mbtypetab[pict_type-1][mb_type].code,
				   mbtypetab[pict_type-1][mb_type].len);
}

int MPEG2CodingBuf::MBType_bits( int pict_type, int mb_type)
{
	return mbtypetab[pict_type-1][mb_type].len;
}

/* generate variable length code for motion_code (6.3.16.3) */
void MPEG2CodingBuf::PutMotionCode(int motion_code)
{
	int abscode;

	abscode = abs( motion_code );
	PutBits(motionvectab[abscode].code,motionvectab[abscode].len);
	if (motion_code!=0)
		PutBits(motion_code<0,1); /* sign, 0=positive, 1=negative */
}

int MPEG2CodingBuf::MotionCode_bits( int motion_code )
{
	int abscode = (motion_code>=0) ? motion_code : -motion_code; 
	return 1+motionvectab[abscode].len;
}

/* generate variable length code for dmvector[t] (6.3.16.3), Table B-11 */
void MPEG2CodingBuf::PutDMV(int dmv)
{
	if (dmv==0)
		PutBits(0,1);
	else if (dmv>0)
		PutBits(2,2);
	else
		PutBits(3,2);
}

int MPEG2CodingBuf::DMV_bits(int dmv)
{
	return dmv == 0 ? 1 : 2;
}

/* generate variable length code for coded_block_pattern (6.3.16.4)
 *
 * 4:2:2, 4:4:4 not implemented
 */
void MPEG2CodingBuf::PutCPB(int cbp)
{
	PutBits(cbptable[cbp].code,cbptable[cbp].len);
}

int MPEG2CodingBuf::CBP_bits(int cbp)
{
	return cbptable[cbp].len;
}


const MPEG2CodingBuf::VLCtable 
MPEG2CodingBuf::addrinctab[33]=
{
  {0x01,1},  {0x03,3},  {0x02,3},  {0x03,4},
  {0x02,4},  {0x03,5},  {0x02,5},  {0x07,7},
  {0x06,7},  {0x0b,8},  {0x0a,8},  {0x09,8},
  {0x08,8},  {0x07,8},  {0x06,8},  {0x17,10},
  {0x16,10}, {0x15,10}, {0x14,10}, {0x13,10},
  {0x12,10}, {0x23,11}, {0x22,11}, {0x21,11},
  {0x20,11}, {0x1f,11}, {0x1e,11}, {0x1d,11},
  {0x1c,11}, {0x1b,11}, {0x1a,11}, {0x19,11},
  {0x18,11}
};


/* Table B-2, B-3, B-4 variable length codes for macroblock_type
 *
 * indexed by [macroblock_type]
 */

const MPEG2CodingBuf::VLCtable 
MPEG2CodingBuf::mbtypetab[3][32]=
{
 /* I */
 {
  {0,0}, {1,1}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0},
  {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0},
  {0,0}, {1,2}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0},
  {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}
 },
 /* P */
 {
  {0,0}, {3,5}, {1,2}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0},
  {1,3}, {0,0}, {1,1}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0},
  {0,0}, {1,6}, {1,5}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0},
  {0,0}, {0,0}, {2,5}, {0,0}, {0,0}, {0,0}, {0,0}, {0,0}
 },
 /* B */
 {
  {0,0}, {3,5}, {0,0}, {0,0}, {2,3}, {0,0}, {3,3}, {0,0},
  {2,4}, {0,0}, {3,4}, {0,0}, {2,2}, {0,0}, {3,2}, {0,0},
  {0,0}, {1,6}, {0,0}, {0,0}, {0,0}, {0,0}, {2,6}, {0,0},
  {0,0}, {0,0}, {3,6}, {0,0}, {0,0}, {0,0}, {2,5}, {0,0}
 }
};


/* Table B-5 ... B-8 variable length codes for macroblock_type in
 *  scalable sequences
 *
 * not implemented
 */

/* Table B-9, variable length codes for coded_block_pattern
 *
 * indexed by [coded_block_pattern]
 */

const MPEG2CodingBuf::VLCtable 
MPEG2CodingBuf::cbptable[64]=
{
  {0x01,9}, {0x0b,5}, {0x09,5}, {0x0d,6}, 
  {0x0d,4}, {0x17,7}, {0x13,7}, {0x1f,8}, 
  {0x0c,4}, {0x16,7}, {0x12,7}, {0x1e,8}, 
  {0x13,5}, {0x1b,8}, {0x17,8}, {0x13,8}, 
  {0x0b,4}, {0x15,7}, {0x11,7}, {0x1d,8}, 
  {0x11,5}, {0x19,8}, {0x15,8}, {0x11,8}, 
  {0x0f,6}, {0x0f,8}, {0x0d,8}, {0x03,9}, 
  {0x0f,5}, {0x0b,8}, {0x07,8}, {0x07,9}, 
  {0x0a,4}, {0x14,7}, {0x10,7}, {0x1c,8}, 
  {0x0e,6}, {0x0e,8}, {0x0c,8}, {0x02,9}, 
  {0x10,5}, {0x18,8}, {0x14,8}, {0x10,8}, 
  {0x0e,5}, {0x0a,8}, {0x06,8}, {0x06,9}, 
  {0x12,5}, {0x1a,8}, {0x16,8}, {0x12,8}, 
  {0x0d,5}, {0x09,8}, {0x05,8}, {0x05,9}, 
  {0x0c,5}, {0x08,8}, {0x04,8}, {0x04,9},
  {0x07,3}, {0x0a,5}, {0x08,5}, {0x0c,6}
};


/* Table B-10, variable length codes for motion_code
 *
 * indexed by [abs(motion_code)]
 * sign of motion_code is treated elsewhere
 */

const MPEG2CodingBuf::VLCtable 
MPEG2CodingBuf::motionvectab[17]=
{
  {0x01,1},  {0x01,2},  {0x01,3},  {0x01,4},
  {0x03,6},  {0x05,7},  {0x04,7},  {0x03,7},
  {0x0b,9},  {0x0a,9},  {0x09,9},  {0x11,10},
  {0x10,10}, {0x0f,10}, {0x0e,10}, {0x0d,10},
  {0x0c,10}
};


/* Table B-11, variable length codes for dmvector
 *
 * treated elsewhere
 */

/* Table B-12, variable length codes for dct_dc_size_luminance
 *
 * indexed by [dct_dc_size_luminance]
 */

const MPEG2CodingBuf::sVLCtable 
MPEG2CodingBuf::DClumtab[12]=
{
  {0x0004,3}, {0x0000,2}, {0x0001,2}, {0x0005,3}, {0x0006,3}, {0x000e,4},
  {0x001e,5}, {0x003e,6}, {0x007e,7}, {0x00fe,8}, {0x01fe,9}, {0x01ff,9}
};


/* Table B-13, variable length codes for dct_dc_size_chrominance
 *
 * indexed by [dct_dc_size_chrominance]
 */

const MPEG2CodingBuf::sVLCtable 
MPEG2CodingBuf::DCchromtab[12]=
{
  {0x0000,2}, {0x0001,2}, {0x0002,2}, {0x0006,3}, {0x000e,4}, {0x001e,5},
  {0x003e,6}, {0x007e,7}, {0x00fe,8}, {0x01fe,9}, {0x03fe,10},{0x03ff,10}
};


/* Table B-14, DCT coefficients table zero
 *
 * indexed by [run][level-1]
 * split into two tables (dct_code_tab1, dct_code_tab2) to reduce size
 * 'first DCT coefficient' condition and 'End of Block' are treated elsewhere
 * codes do not include s (sign bit)
 */

const MPEG2CodingBuf::VLCtable 
MPEG2CodingBuf::dct_code_tab1[2][40]=
{
 /* run = 0, level = 1...40 */
 {
  {0x03, 2}, {0x04, 4}, {0x05, 5}, {0x06, 7},
  {0x26, 8}, {0x21, 8}, {0x0a,10}, {0x1d,12},
  {0x18,12}, {0x13,12}, {0x10,12}, {0x1a,13},
  {0x19,13}, {0x18,13}, {0x17,13}, {0x1f,14},
  {0x1e,14}, {0x1d,14}, {0x1c,14}, {0x1b,14},
  {0x1a,14}, {0x19,14}, {0x18,14}, {0x17,14},
  {0x16,14}, {0x15,14}, {0x14,14}, {0x13,14},
  {0x12,14}, {0x11,14}, {0x10,14}, {0x18,15},
  {0x17,15}, {0x16,15}, {0x15,15}, {0x14,15},
  {0x13,15}, {0x12,15}, {0x11,15}, {0x10,15}
 },
 /* run = 1, level = 1...18 */
 {
  {0x03, 3}, {0x06, 6}, {0x25, 8}, {0x0c,10},
  {0x1b,12}, {0x16,13}, {0x15,13}, {0x1f,15},
  {0x1e,15}, {0x1d,15}, {0x1c,15}, {0x1b,15},
  {0x1a,15}, {0x19,15}, {0x13,16}, {0x12,16},
  {0x11,16}, {0x10,16}, {0x00, 0}, {0x00, 0},
  {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0},
  {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0},
  {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0},
  {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0},
  {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}
 }
};

const MPEG2CodingBuf::VLCtable 
MPEG2CodingBuf::dct_code_tab2[30][5]=
{
  /* run = 2...31, level = 1...5 */
  {{0x05, 4}, {0x04, 7}, {0x0b,10}, {0x14,12}, {0x14,13}},
  {{0x07, 5}, {0x24, 8}, {0x1c,12}, {0x13,13}, {0x00, 0}},
  {{0x06, 5}, {0x0f,10}, {0x12,12}, {0x00, 0}, {0x00, 0}},
  {{0x07, 6}, {0x09,10}, {0x12,13}, {0x00, 0}, {0x00, 0}},
  {{0x05, 6}, {0x1e,12}, {0x14,16}, {0x00, 0}, {0x00, 0}},
  {{0x04, 6}, {0x15,12}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x07, 7}, {0x11,12}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x05, 7}, {0x11,13}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x27, 8}, {0x10,13}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x23, 8}, {0x1a,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x22, 8}, {0x19,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x20, 8}, {0x18,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x0e,10}, {0x17,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x0d,10}, {0x16,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x08,10}, {0x15,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1f,12}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1a,12}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x19,12}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x17,12}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x16,12}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1f,13}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1e,13}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1d,13}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1c,13}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1b,13}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1f,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1e,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1d,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1c,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1b,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}}
};


/* Table B-15, DCT coefficients table one
 *
 * indexed by [run][level-1]
 * split into two tables (dct_code_tab1a, dct_code_tab2a) to reduce size
 * 'End of Block' is treated elsewhere
 * codes do not include s (sign bit)
 */

const MPEG2CodingBuf::VLCtable 
MPEG2CodingBuf::dct_code_tab1a[2][40]=
{
 /* run = 0, level = 1...40 */
 {
  {0x02, 2}, {0x06, 3}, {0x07, 4}, {0x1c, 5},
  {0x1d, 5}, {0x05, 6}, {0x04, 6}, {0x7b, 7},
  {0x7c, 7}, {0x23, 8}, {0x22, 8}, {0xfa, 8},
  {0xfb, 8}, {0xfe, 8}, {0xff, 8}, {0x1f,14},
  {0x1e,14}, {0x1d,14}, {0x1c,14}, {0x1b,14},
  {0x1a,14}, {0x19,14}, {0x18,14}, {0x17,14},
  {0x16,14}, {0x15,14}, {0x14,14}, {0x13,14},
  {0x12,14}, {0x11,14}, {0x10,14}, {0x18,15},
  {0x17,15}, {0x16,15}, {0x15,15}, {0x14,15},
  {0x13,15}, {0x12,15}, {0x11,15}, {0x10,15}
 },
 /* run = 1, level = 1...18 */
 {
  {0x02, 3}, {0x06, 5}, {0x79, 7}, {0x27, 8},
  {0x20, 8}, {0x16,13}, {0x15,13}, {0x1f,15},
  {0x1e,15}, {0x1d,15}, {0x1c,15}, {0x1b,15},
  {0x1a,15}, {0x19,15}, {0x13,16}, {0x12,16},
  {0x11,16}, {0x10,16}, {0x00, 0}, {0x00, 0},
  {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0},
  {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0},
  {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0},
  {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0},
  {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}
 }
};

const MPEG2CodingBuf::VLCtable 
MPEG2CodingBuf::dct_code_tab2a[30][5]=
{
  /* run = 2...31, level = 1...5 */
  {{0x05, 5}, {0x07, 7}, {0xfc, 8}, {0x0c,10}, {0x14,13}},
  {{0x07, 5}, {0x26, 8}, {0x1c,12}, {0x13,13}, {0x00, 0}},
  {{0x06, 6}, {0xfd, 8}, {0x12,12}, {0x00, 0}, {0x00, 0}},
  {{0x07, 6}, {0x04, 9}, {0x12,13}, {0x00, 0}, {0x00, 0}},
  {{0x06, 7}, {0x1e,12}, {0x14,16}, {0x00, 0}, {0x00, 0}},
  {{0x04, 7}, {0x15,12}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x05, 7}, {0x11,12}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x78, 7}, {0x11,13}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x7a, 7}, {0x10,13}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x21, 8}, {0x1a,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x25, 8}, {0x19,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x24, 8}, {0x18,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x05, 9}, {0x17,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x07, 9}, {0x16,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x0d,10}, {0x15,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1f,12}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1a,12}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x19,12}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x17,12}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x16,12}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1f,13}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1e,13}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1d,13}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1c,13}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1b,13}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1f,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1e,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1d,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1c,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}},
  {{0x1b,16}, {0x00, 0}, {0x00, 0}, {0x00, 0}, {0x00, 0}}
};



/* 
 * Local variables:
 *  c-file-style: "stroustrup"
 *  tab-width: 4
 *  indent-tabs-mode: nil
 * End:
 */