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/* max compressed frame size */
#define MPA_MAX_CODED_FRAME_SIZE 1200
#define MPA_FRAME_SIZE 1152
#define MPA_MAX_CHANNELS 2
#define SAMPLES_BUF_SIZE 4096
#define SBLIMIT 32 /* number of subbands */
#define DCT_BITS 14 /* number of bits for the DCT */
#define MUL(a,b) (((a) * (b)) >> DCT_BITS)
#define FIX(a) ((int)((a) * (1 << DCT_BITS)))
typedef struct MpegAudioContext {
PutBitContext pb;
int nb_channels;
int freq, bit_rate;
int lsf; /* 1 if mpeg2 low bitrate selected */
int bitrate_index; /* bit rate */
int freq_index;
int frame_size; /* frame size, in bits, without padding */
INT64 nb_samples; /* total number of samples encoded */
/* padding computation */
int frame_frac, frame_frac_incr, do_padding;
short samples_buf[MPA_MAX_CHANNELS][SAMPLES_BUF_SIZE]; /* buffer for filter */
int samples_offset[MPA_MAX_CHANNELS]; /* offset in samples_buf */
int sb_samples[MPA_MAX_CHANNELS][3][12][SBLIMIT];
unsigned char scale_factors[MPA_MAX_CHANNELS][SBLIMIT][3]; /* scale factors */
/* code to group 3 scale factors */
unsigned char scale_code[MPA_MAX_CHANNELS][SBLIMIT];
int sblimit; /* number of used subbands */
const unsigned char *alloc_table;
} MpegAudioContext;
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