diff options
| -rw-r--r-- | libavcodec/ac3dec_data.c | 21 | ||||
| -rw-r--r-- | libavcodec/ac3dec_data.h | 2 | ||||
| -rw-r--r-- | libavcodec/eac3dec.c | 12 |
3 files changed, 18 insertions, 17 deletions
diff --git a/libavcodec/ac3dec_data.c b/libavcodec/ac3dec_data.c index 2a3719ea07..b9f98f904e 100644 --- a/libavcodec/ac3dec_data.c +++ b/libavcodec/ac3dec_data.c @@ -87,19 +87,18 @@ const int16_t ff_eac3_gaq_remap_2_4_a[9][2] = { /** * Table E3.6, Gk=2 & Gk=4, B * Large mantissa inverse quantization, negative mantissa remapping offsets - * Table values from the spec are right-shifted by 8 to simplify calculations. * ff_eac3_gaq_remap_3_4_b[hebap-8][Gk=2,4] */ -const int8_t ff_eac3_gaq_remap_2_4_b[9][2] = { - { -22, -5 }, - { -46, -20 }, - { -56, -26 }, - { -60, -29 }, - { -62, -31 }, - { -63, -32 }, - { -64, -32 }, - { -64, -32 }, - { -64, -32 }, +const int16_t ff_eac3_gaq_remap_2_4_b[9][2] = { + { -5461, -1170 }, + { -11703, -4915 }, + { -14199, -6606 }, + { -15327, -7412 }, + { -15864, -7805 }, + { -16126, -7999 }, + { -16255, -8096 }, + { -16320, -8144 }, + { -16352, -8168 } }; static const int16_t vq_hebap1[4][6] = { diff --git a/libavcodec/ac3dec_data.h b/libavcodec/ac3dec_data.h index 486d04a40b..c9bb58686b 100644 --- a/libavcodec/ac3dec_data.h +++ b/libavcodec/ac3dec_data.h @@ -29,7 +29,7 @@ extern const uint8_t ff_eac3_hebap_tab[64]; extern const uint8_t ff_eac3_bits_vs_hebap[20]; extern const int16_t ff_eac3_gaq_remap_1[12]; extern const int16_t ff_eac3_gaq_remap_2_4_a[9][2]; -extern const int8_t ff_eac3_gaq_remap_2_4_b[9][2]; +extern const int16_t ff_eac3_gaq_remap_2_4_b[9][2]; extern const int16_t (* const ff_eac3_mantissa_vq[8])[6]; extern const uint8_t ff_eac3_frm_expstr[32][6]; diff --git a/libavcodec/eac3dec.c b/libavcodec/eac3dec.c index 8af729dc22..62f6d792cf 100644 --- a/libavcodec/eac3dec.c +++ b/libavcodec/eac3dec.c @@ -178,19 +178,21 @@ void ff_eac3_decode_transform_coeffs_aht_ch(AC3DecodeContext *s, int ch) if (mant == -(1 << (gbits-1))) { /* large mantissa */ int b; - mant = get_sbits(gbc, bits-2+log_gain) << (26-log_gain-bits); + int mbits = bits - (2 - log_gain); + mant = get_sbits(gbc, mbits); + mant <<= (23 - (mbits - 1)); /* remap mantissa value to correct for asymmetric quantization */ if (mant >= 0) - b = 32768 >> (log_gain+8); + b = 1 << (23 - (mbits - 1)); else - b = ff_eac3_gaq_remap_2_4_b[hebap-8][log_gain-1]; - mant += (ff_eac3_gaq_remap_2_4_a[hebap-8][log_gain-1] * (mant>>8) + b) >> 7; + b = ff_eac3_gaq_remap_2_4_b[hebap-8][log_gain-1] << 8; + mant += (((ff_eac3_gaq_remap_2_4_a[hebap-8][log_gain-1] << 8) * (int64_t)mant) >> 23) + b; } else { /* small mantissa, no GAQ, or Gk=1 */ mant <<= 24 - bits; if (!log_gain) { /* remap mantissa value for no GAQ or Gk=1 */ - mant += (ff_eac3_gaq_remap_1[hebap-8] * (mant>>8)) >> 7; + mant += ((ff_eac3_gaq_remap_1[hebap-8] << 8) * (int64_t)mant) >> 23; } } s->pre_mantissa[ch][bin][blk] = mant; |