diff options
Diffstat (limited to 'libavcodec/ac3enc.c')
| -rw-r--r-- | libavcodec/ac3enc.c | 34 |
1 files changed, 17 insertions, 17 deletions
diff --git a/libavcodec/ac3enc.c b/libavcodec/ac3enc.c index debd63d56a..cc8e59e7df 100644 --- a/libavcodec/ac3enc.c +++ b/libavcodec/ac3enc.c @@ -112,6 +112,7 @@ typedef struct AC3Block { uint8_t coeff_shift[AC3_MAX_CHANNELS]; ///< fixed-point coefficient shift values uint8_t new_rematrixing_strategy; ///< send new rematrixing flags in this block uint8_t rematrixing_flags[4]; ///< rematrixing flags + struct AC3Block *exp_ref_block[AC3_MAX_CHANNELS]; ///< reference blocks for EXP_REUSE } AC3Block; /** @@ -692,7 +693,7 @@ static void encode_exponents_blk_ch(uint8_t *exp, int nb_exps, int exp_strategy) static void encode_exponents(AC3EncodeContext *s) { int blk, blk1, ch; - uint8_t *exp, *exp1, *exp_strategy; + uint8_t *exp, *exp_strategy; int nb_coefs, num_reuse_blocks; for (ch = 0; ch < s->channels; ch++) { @@ -704,9 +705,13 @@ static void encode_exponents(AC3EncodeContext *s) while (blk < AC3_MAX_BLOCKS) { blk1 = blk + 1; - /* count the number of EXP_REUSE blocks after the current block */ - while (blk1 < AC3_MAX_BLOCKS && exp_strategy[blk1] == EXP_REUSE) + /* count the number of EXP_REUSE blocks after the current block + and set exponent reference block pointers */ + s->blocks[blk].exp_ref_block[ch] = &s->blocks[blk]; + while (blk1 < AC3_MAX_BLOCKS && exp_strategy[blk1] == EXP_REUSE) { + s->blocks[blk1].exp_ref_block[ch] = &s->blocks[blk]; blk1++; + } num_reuse_blocks = blk1 - blk - 1; /* for the EXP_REUSE case we select the min of the exponents */ @@ -714,15 +719,8 @@ static void encode_exponents(AC3EncodeContext *s) encode_exponents_blk_ch(exp, nb_coefs, exp_strategy[blk]); - /* copy encoded exponents for reuse case */ - exp1 = exp + AC3_MAX_COEFS; - while (blk < blk1-1) { - memcpy(exp1, exp, nb_coefs * sizeof(*exp)); - exp1 += AC3_MAX_COEFS; - blk++; - } + exp += AC3_MAX_COEFS * (num_reuse_blocks + 1); blk = blk1; - exp = exp1; } } } @@ -1035,7 +1033,7 @@ static int bit_alloc(AC3EncodeContext *s, int snr_offset) reset_block_bap(s); mantissa_bits = 0; for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) { - AC3Block *block = &s->blocks[blk]; + AC3Block *block; // initialize grouped mantissa counts. these are set so that they are // padded to the next whole group size when bits are counted in // compute_mantissa_size_final @@ -1047,9 +1045,8 @@ static int bit_alloc(AC3EncodeContext *s, int snr_offset) blocks within a frame are the exponent values. We can take advantage of that by reusing the bit allocation pointers whenever we reuse exponents. */ - if (s->exp_strategy[ch][blk] == EXP_REUSE) { - memcpy(block->bap[ch], s->blocks[blk-1].bap[ch], AC3_MAX_COEFS); - } else { + block = s->blocks[blk].exp_ref_block[ch]; + if (s->exp_strategy[ch][blk] != EXP_REUSE) { ff_ac3_bit_alloc_calc_bap(block->mask[ch], block->psd[ch], 0, s->nb_coefs[ch], snr_offset, s->bit_alloc.floor, ff_ac3_bap_tab, @@ -1352,12 +1349,14 @@ static void quantize_mantissas(AC3EncodeContext *s) for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) { AC3Block *block = &s->blocks[blk]; + AC3Block *ref_block; s->mant1_cnt = s->mant2_cnt = s->mant4_cnt = 0; s->qmant1_ptr = s->qmant2_ptr = s->qmant4_ptr = NULL; for (ch = 0; ch < s->channels; ch++) { + ref_block = block->exp_ref_block[ch]; quantize_mantissas_blk_ch(s, block->fixed_coef[ch], - block->exp[ch], block->bap[ch], + ref_block->exp[ch], ref_block->bap[ch], block->qmant[ch], s->nb_coefs[ch]); } } @@ -1516,9 +1515,10 @@ static void output_audio_block(AC3EncodeContext *s, int blk) /* mantissas */ for (ch = 0; ch < s->channels; ch++) { int b, q; + AC3Block *ref_block = block->exp_ref_block[ch]; for (i = 0; i < s->nb_coefs[ch]; i++) { q = block->qmant[ch][i]; - b = block->bap[ch][i]; + b = ref_block->bap[ch][i]; switch (b) { case 0: break; case 1: if (q != 128) put_bits(&s->pb, 5, q); break; |