mhead.h

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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 =)

____________________________________________________________________________*/

/* portable copy of eco\mhead.h */
/* mpeg audio header   */
typedef struct
{
   int sync;			/* 1 if valid sync */
   int id;
   int option;
   int prot;
   int br_index;
   int sr_index;
   int pad;
   int private_bit;
   int mode;
   int mode_ext;
   int cr;
   int original;
   int emphasis;
}
MPEG_HEAD;

/* portable mpeg audio decoder, decoder functions */
typedef struct
{
   int in_bytes;
   int out_bytes;
}
IN_OUT;


typedef struct
{
   int channels;
   int outvalues;
   long samprate;
   int bits;
   int framebytes;
   int type;
}
DEC_INFO;


#ifdef __cplusplus
extern "C"
{
#endif

   int head_info(unsigned char *buf, unsigned int n, MPEG_HEAD * h);
   int head_info2(unsigned char *buf,
	   unsigned int n, MPEG_HEAD * h, int *br);
	int head_info3(unsigned char *buf, unsigned int n, MPEG_HEAD *h, int*br, unsigned int *searchForward);
/* head_info returns framebytes > 0 for success */
/* audio_decode_init returns 1 for success, 0 for fail */
/* audio_decode returns in_bytes = 0 on sync loss */

   int audio_decode_init(MPEG_HEAD * h, int framebytes_arg,
		   int reduction_code, int transform_code, int convert_code,
			 int freq_limit);
   void audio_decode_info(DEC_INFO * info);
   IN_OUT audio_decode(unsigned char *bs, short *pcm);

   int audio_decode8_init(MPEG_HEAD * h, int framebytes_arg,
		   int reduction_code, int transform_code, int convert_code,
			  int freq_limit);
   void audio_decode8_info(DEC_INFO * info);
   IN_OUT audio_decode8(unsigned char *bs, short *pcmbuf);

/*-- integer decode --*/
   int i_audio_decode_init(MPEG_HEAD * h, int framebytes_arg,
		   int reduction_code, int transform_code, int convert_code,
			   int freq_limit);
   void i_audio_decode_info(DEC_INFO * info);
   IN_OUT i_audio_decode(unsigned char *bs, short *pcm);



#ifdef __cplusplus
}
#endif