mirror of https://git.ffmpeg.org/ffmpeg.git
33 lines
1.0 KiB
C
33 lines
1.0 KiB
C
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#define AC3_FRAME_SIZE (6*256)
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#define AC3_MAX_CODED_FRAME_SIZE 3840 /* in bytes */
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#define AC3_MAX_CHANNELS 2 /* we handle at most two channels, although
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AC3 allows 6 channels */
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typedef struct AC3EncodeContext {
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PutBitContext pb;
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int nb_channels;
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int bit_rate;
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int sample_rate;
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int bsid;
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int frame_size_min; /* minimum frame size in case rounding is necessary */
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int frame_size; /* current frame size in words */
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int halfratecod;
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int frmsizecod;
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int fscod; /* frequency */
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int acmod;
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int bsmod;
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short last_samples[AC3_MAX_CHANNELS][256];
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int chbwcod[AC3_MAX_CHANNELS];
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int nb_coefs[AC3_MAX_CHANNELS];
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/* bitrate allocation control */
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int sgaincod, sdecaycod, fdecaycod, dbkneecod, floorcod;
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int sgain, sdecay, fdecay, dbknee, floor;
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int csnroffst;
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int fgaincod[AC3_MAX_CHANNELS];
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int fsnroffst[AC3_MAX_CHANNELS];
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/* mantissa encoding */
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int mant1_cnt, mant2_cnt, mant4_cnt;
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} AC3EncodeContext;
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