csbtb.c

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/*____________________________________________________________________________
	
	MP3 Decoding Libraries
	Lanuguages used: C, C++, ASM

	As much as I would love to, I cannot take
	full credit for writing this code.
	Xing Technology	made MPEG-Layer 3 for us
	to decode. =)
	- ULTiMaTuM -

	MPEG-Layer 3 (MP3)
	Copyright (C) 1995-1997 Xing Technology

  	NOTE: I only edited the bare-minimum. 90%
		of this is original decoding code...
		Hmm... that sounds strange =)

____________________________________________________________________________*/

/****  csbtb.c  ***************************************************
include to csbt.c

MPEG audio decoder, dct and window - byte (8 pcm bit output)
portable C

******************************************************************/
/*============================================================*/
/*============================================================*/
void windowB(float *vbuf, int vb_ptr, unsigned char *pcm);
void windowB_dual(float *vbuf, int vb_ptr, unsigned char *pcm);
void windowB16(float *vbuf, int vb_ptr, unsigned char *pcm);
void windowB16_dual(float *vbuf, int vb_ptr, unsigned char *pcm);
void windowB8(float *vbuf, int vb_ptr, unsigned char *pcm);
void windowB8_dual(float *vbuf, int vb_ptr, unsigned char *pcm);

/*============================================================*/
void sbtB_mono(float *sample, unsigned char *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      fdct32(sample, vbuf + vb_ptr);
      windowB(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 32) & 511;
      pcm += 32;
   }

}
/*------------------------------------------------------------*/
void sbtB_dual(float *sample, unsigned char *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      fdct32_dual(sample, vbuf + vb_ptr);
      fdct32_dual(sample + 1, vbuf2 + vb_ptr);
      windowB_dual(vbuf, vb_ptr, pcm);
      windowB_dual(vbuf2, vb_ptr, pcm + 1);
      sample += 64;
      vb_ptr = (vb_ptr - 32) & 511;
      pcm += 64;
   }


}
/*------------------------------------------------------------*/
/* convert dual to mono */
void sbtB_dual_mono(float *sample, unsigned char *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      fdct32_dual_mono(sample, vbuf + vb_ptr);
      windowB(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 32) & 511;
      pcm += 32;
   }

}
/*------------------------------------------------------------*/
/* convert dual to left */
void sbtB_dual_left(float *sample, unsigned char *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      fdct32_dual(sample, vbuf + vb_ptr);
      windowB(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 32) & 511;
      pcm += 32;
   }
}
/*------------------------------------------------------------*/
/* convert dual to right */
void sbtB_dual_right(float *sample, unsigned char *pcm, int n)
{
   int i;

   sample++;			/* point to right chan */
   for (i = 0; i < n; i++)
   {
      fdct32_dual(sample, vbuf + vb_ptr);
      windowB(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 32) & 511;
      pcm += 32;
   }
}
/*------------------------------------------------------------*/
/*---------------- 16 pt sbt's  -------------------------------*/
/*------------------------------------------------------------*/
void sbtB16_mono(float *sample, unsigned char *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      fdct16(sample, vbuf + vb_ptr);
      windowB16(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 16) & 255;
      pcm += 16;
   }


}
/*------------------------------------------------------------*/
void sbtB16_dual(float *sample, unsigned char *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      fdct16_dual(sample, vbuf + vb_ptr);
      fdct16_dual(sample + 1, vbuf2 + vb_ptr);
      windowB16_dual(vbuf, vb_ptr, pcm);
      windowB16_dual(vbuf2, vb_ptr, pcm + 1);
      sample += 64;
      vb_ptr = (vb_ptr - 16) & 255;
      pcm += 32;
   }
}
/*------------------------------------------------------------*/
void sbtB16_dual_mono(float *sample, unsigned char *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      fdct16_dual_mono(sample, vbuf + vb_ptr);
      windowB16(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 16) & 255;
      pcm += 16;
   }
}
/*------------------------------------------------------------*/
void sbtB16_dual_left(float *sample, unsigned char *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      fdct16_dual(sample, vbuf + vb_ptr);
      windowB16(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 16) & 255;
      pcm += 16;
   }
}
/*------------------------------------------------------------*/
void sbtB16_dual_right(float *sample, unsigned char *pcm, int n)
{
   int i;

   sample++;
   for (i = 0; i < n; i++)
   {
      fdct16_dual(sample, vbuf + vb_ptr);
      windowB16(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 16) & 255;
      pcm += 16;
   }
}
/*------------------------------------------------------------*/
/*---------------- 8 pt sbt's  -------------------------------*/
/*------------------------------------------------------------*/
void sbtB8_mono(float *sample, unsigned char *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      fdct8(sample, vbuf + vb_ptr);
      windowB8(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 8) & 127;
      pcm += 8;
   }

}
/*------------------------------------------------------------*/
void sbtB8_dual(float *sample, unsigned char *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      fdct8_dual(sample, vbuf + vb_ptr);
      fdct8_dual(sample + 1, vbuf2 + vb_ptr);
      windowB8_dual(vbuf, vb_ptr, pcm);
      windowB8_dual(vbuf2, vb_ptr, pcm + 1);
      sample += 64;
      vb_ptr = (vb_ptr - 8) & 127;
      pcm += 16;
   }
}
/*------------------------------------------------------------*/
void sbtB8_dual_mono(float *sample, unsigned char *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      fdct8_dual_mono(sample, vbuf + vb_ptr);
      windowB8(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 8) & 127;
      pcm += 8;
   }
}
/*------------------------------------------------------------*/
void sbtB8_dual_left(float *sample, unsigned char *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      fdct8_dual(sample, vbuf + vb_ptr);
      windowB8(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 8) & 127;
      pcm += 8;
   }
}
/*------------------------------------------------------------*/
void sbtB8_dual_right(float *sample, unsigned char *pcm, int n)
{
   int i;

   sample++;
   for (i = 0; i < n; i++)
   {
      fdct8_dual(sample, vbuf + vb_ptr);
      windowB8(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 8) & 127;
      pcm += 8;
   }
}
/*------------------------------------------------------------*/