/***************************************************************************

 *

 *  FILE NAME:  CODER.C

 *

 *  Main program of the EFR coder at 12.2 kbit/s.

 *

 *    Usage : coder speech_file  bitstream_file

 *

 *    Format for speech_file:

 *      Speech is read from a binary file of 16 bits data.

 *

 *    Format for bitstream_file:

 *      244  words (2-byte) containing 244 bits.

 *          Bit 0 = 0x0000 and Bit 1 = 0x0001

 *      One word (2-byte) for voice activity decision (VAD) flag bit

 *          0x0000 -> inactive (no detected speech activity);

 *          0x0001 -> active

 *      One word (2-byte) for speech (SP) flag bit

 *          0x0000 -> inactive (no transmission of speech frames);

 *          0x0001 -> active

 *

 ***************************************************************************/



#include <string.h>



#include "typedef.h"

#include "basic_op.h"

#include "sig_proc.h"

#include "codec.h"

#include "cnst.h"

#include "e_homing.h"



#include "dtx.h"



Word16 dtx_mode;

extern Word16 txdtx_ctrl;



/* L_FRAME, M, PRM_SIZE, AZ_SIZE, SERIAL_SIZE: defined in "cnst.h" */



void Encode( Word16 *in, Word32 size, Word16 *out )

{

    extern Word16 *new_speech;  /* Pointer to new speech data            */



    Word16 prm[PRM_SIZE];       /* Analysis parameters.                  */

    Word16 serial[SERIAL_SIZE]; /* Output bitstream buffer               */

    Word16 syn[L_FRAME];        /* Buffer for synthesis speech           */



    Word16 frame;



    Word16 vad, sp;



    Word16 reset_flag;

    Word16 i;



		Word32 part;



    /*----------------------------------------------------------------------*

     * Open speech file and result file (output serial bit stream)          *

     *----------------------------------------------------------------------*/



    dtx_mode = 0;               /* DTX disabled by default */



    /*-----------------------------------------------------------------------*

     * Initialisation of the coder.                                          *

     *-----------------------------------------------------------------------*/



    reset_enc (); /* Bring the encoder, VAD and DTX to the initial state */



    /* Loop for each "L_FRAME" speech data. */



    frame = 0;

    while (size > 0)

    {

				memset( new_speech, 0, L_FRAME*2 );



				part = size;

				if (part > L_FRAME)

					part = L_FRAME;

				memcpy( new_speech, in, part*2 );

				in += part;

				size -= part;



        /* Check whether this frame is an encoder homing frame */

        reset_flag = encoder_homing_frame_test (new_speech);



				for (i = 0; i < L_FRAME; i++)   /* Delete the 3 LSBs (13-bit input) */

				{

						new_speech[i] = new_speech[i] & 0xfff8;

				}



        Pre_Process (new_speech, L_FRAME);           /* filter + downscaling */



        Coder_12k2 (prm, syn);  /* Find speech parameters   */



        if ((txdtx_ctrl & TX_SP_FLAG) == 0)

        {

            /* Write comfort noise parameters into the parameter frame.

            Use old parameters in case SID frame is not to be updated */

            CN_encoding (prm, txdtx_ctrl);

        }

        Prm2bits_12k2 (prm, &serial[0]); /* Parameters to serial bits */



        if ((txdtx_ctrl & TX_SP_FLAG) == 0)

        {

            /* Insert SID codeword into the serial parameter frame */

            sid_codeword_encoding (&serial[0]);

        }



        /* Write the bit stream to file */

				memcpy( out, serial, SERIAL_SIZE*2 );

				out += SERIAL_SIZE;



        /* Write the VAD- and SP-flags to file after the speech

        parameter bit stream */

        vad = 0;

        sp = 0;



        if ((txdtx_ctrl & TX_VAD_FLAG) != 0)

        {

            vad = 1;

        }

        if ((txdtx_ctrl & TX_SP_FLAG) != 0)

        {

            sp = 1;

        }



        if (reset_flag != 0)

        {

            reset_enc (); /*Bring the encoder, VAD and DTX to the home state */

        }

    }

}