/* putbits.c, bit-level output                                              */

/* Copyright (C) 1996, MPEG Software Simulation Group. All Rights Reserved. */

/*
 * Disclaimer of Warranty
 *
 * These software programs are available to the user without any license fee or
 * royalty on an "as is" basis.  The MPEG Software Simulation Group disclaims
 * any and all warranties, whether express, implied, or statuary, including any
 * implied warranties or merchantability or of fitness for a particular
 * purpose.  In no event shall the copyright-holder be liable for any
 * incidental, punitive, or consequential damages of any kind whatsoever
 * arising from the use of these programs.
 *
 * This disclaimer of warranty extends to the user of these programs and user's
 * customers, employees, agents, transferees, successors, and assigns.
 *
 * The MPEG Software Simulation Group does not represent or warrant that the
 * programs furnished hereunder are free of infringement of any third-party
 * patents.
 *
 * Commercial implementations of MPEG-1 and MPEG-2 video, including shareware,
 * are subject to royalty fees to patent holders.  Many of these patents are
 * general enough such that they are unavoidable regardless of implementation
 * design.
 *
 */

#include <stdio.h>
#include "config.h"

extern FILE *outfile;		/* the only global var we need here */
extern int outsk;

/* private data */
static unsigned char outbfr;
static int outcnt;
static int bytecnt;

/* initialize buffer, call once before first putbits or alignbits */
void initbits()
{
    outcnt = 8;
    bytecnt = 0;
}

/* write rightmost n (0<=n<=32) bits of val to outfile */
void putbits(val, n)
int val;
int n;
{
    int i;
    unsigned int mask;
    static char szBuf[2048];
    static int ib = 0;

    mask = 1 << (n - 1);	/* selects first (leftmost) bit */

    for (i = 0; i < n; i++) {
	outbfr <<= 1;

	if (val & mask)
	    outbfr |= 1;

	mask >>= 1;		/* select next bit */
	outcnt--;

	if (outcnt == 0) {	/* 8 bit buffer full */
	    if (ib < 2047) {
		szBuf[ib++] = outbfr;
	    } else if (ib == 2047) {
		szBuf[ib++] = outbfr;
		write(outsk, szBuf, ib);
//		write(outsk, szBuf, ib);
//		write(outsk, szBuf, ib);
	    } else {
		write(outsk, &outbfr, 1);
	    }
/*
      putc(outbfr,outfile);
*/
	    outcnt = 8;
	    bytecnt++;
	}
    }
}

/* zero bit stuffing to next byte boundary (5.2.3, 6.2.1) */
void alignbits()
{
    if (outcnt != 8)
	putbits(0, outcnt);
}

/* return total number of generated bits */
int bitcount()
{
    return 8 * bytecnt + (8 - outcnt);
}