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#include "common.h"
#include "encoder.h"
#include "musicin.h"
#include "options.h"
int available_bits(layer *info, options *glopts);
struct slotinfo {
double average;
double frac;
int whole;
double lag;
int extra;
} slots;
/* function returns the number of available bits */
int available_bits(layer *info, options *glopts) {
int adb;
slots.extra = 0; /* be default, no extra slots */
slots.average = ( 1152.0 / s_freq[info->version][info->sampling_frequency]) *
((double)bitrate[info->version][info->bitrate_index] / 8.0);
slots.whole = (int)slots.average;
slots.frac = slots.average - (double)slots.whole;
#ifdef VBR
if (slots.frac != 0 && glopts->usepadbit && glopts->vbr==FALSE)
#else
if (slots.frac != 0 && glopts->usepadbit)
#endif
{
if (slots.lag > (slots.frac-1.0) ) /* no padding for this frame */
{
slots.lag -= slots.frac;
slots.extra = 0;
info->padding = 0;
}
else /* padding */
{
slots.extra = 1;
info->padding = 1;
slots.lag += (1-slots.frac);
}
}
adb = (slots.whole + slots.extra ) * 8;
return adb;
}
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