diff options
Diffstat (limited to 'libavcodec/ac3dsp.c')
-rw-r--r-- | libavcodec/ac3dsp.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/libavcodec/ac3dsp.c b/libavcodec/ac3dsp.c index 77250a351b..cd4d30b8f2 100644 --- a/libavcodec/ac3dsp.c +++ b/libavcodec/ac3dsp.c @@ -127,6 +127,28 @@ static void ac3_bit_alloc_calc_bap_c(int16_t *mask, int16_t *psd, } while (end > ff_ac3_band_start_tab[band++]); } +static int ac3_compute_mantissa_size_c(int mant_cnt[5], uint8_t *bap, + int nb_coefs) +{ + int bits, b, i; + + bits = 0; + for (i = 0; i < nb_coefs; i++) { + b = bap[i]; + if (b <= 4) { + // bap=1 to bap=4 will be counted in compute_mantissa_size_final + mant_cnt[b]++; + } else if (b <= 13) { + // bap=5 to bap=13 use (bap-1) bits + bits += b - 1; + } else { + // bap=14 uses 14 bits and bap=15 uses 16 bits + bits += (b == 14) ? 14 : 16; + } + } + return bits; +} + av_cold void ff_ac3dsp_init(AC3DSPContext *c, int bit_exact) { c->ac3_exponent_min = ac3_exponent_min_c; @@ -135,6 +157,7 @@ av_cold void ff_ac3dsp_init(AC3DSPContext *c, int bit_exact) c->ac3_rshift_int32 = ac3_rshift_int32_c; c->float_to_fixed24 = float_to_fixed24_c; c->bit_alloc_calc_bap = ac3_bit_alloc_calc_bap_c; + c->compute_mantissa_size = ac3_compute_mantissa_size_c; if (ARCH_ARM) ff_ac3dsp_init_arm(c, bit_exact); |