diff options
| -rw-r--r-- | libavcodec/ac3enc.c | 40 | ||||
| -rw-r--r-- | libavcodec/ac3enc.h | 2 | ||||
| -rw-r--r-- | libavcodec/ac3enc_template.c | 2 |
3 files changed, 36 insertions, 8 deletions
diff --git a/libavcodec/ac3enc.c b/libavcodec/ac3enc.c index c138f99207..d454654c00 100644 --- a/libavcodec/ac3enc.c +++ b/libavcodec/ac3enc.c @@ -527,19 +527,46 @@ static void encode_exponents(AC3EncodeContext *s) /** + * Count exponent bits based on bandwidth, coupling, and exponent strategies. + */ +static int count_exponent_bits(AC3EncodeContext *s) +{ + int blk, ch; + int nb_groups, bit_count; + + bit_count = 0; + for (blk = 0; blk < s->num_blocks; blk++) { + AC3Block *block = &s->blocks[blk]; + for (ch = !block->cpl_in_use; ch <= s->channels; ch++) { + int exp_strategy = s->exp_strategy[ch][blk]; + int cpl = (ch == CPL_CH); + int nb_coefs = block->end_freq[ch] - s->start_freq[ch]; + + if (exp_strategy == EXP_REUSE) + continue; + + nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_coefs]; + bit_count += 4 + (nb_groups * 7); + } + } + + return bit_count; +} + + +/** * Group exponents. * 3 delta-encoded exponents are in each 7-bit group. The number of groups * varies depending on exponent strategy and bandwidth. */ -static void group_exponents(AC3EncodeContext *s) +void ff_ac3_group_exponents(AC3EncodeContext *s) { int blk, ch, i, cpl; - int group_size, nb_groups, bit_count; + int group_size, nb_groups; uint8_t *p; int delta0, delta1, delta2; int exp0, exp1; - bit_count = 0; for (blk = 0; blk < s->num_blocks; blk++) { AC3Block *block = &s->blocks[blk]; for (ch = !block->cpl_in_use; ch <= s->channels; ch++) { @@ -549,7 +576,6 @@ static void group_exponents(AC3EncodeContext *s) cpl = (ch == CPL_CH); group_size = exp_strategy + (exp_strategy == EXP_D45); nb_groups = exponent_group_tab[cpl][exp_strategy-1][block->end_freq[ch]-s->start_freq[ch]]; - bit_count += 4 + (nb_groups * 7); p = block->exp[ch] + s->start_freq[ch] - cpl; /* DC exponent */ @@ -581,8 +607,6 @@ static void group_exponents(AC3EncodeContext *s) } } } - - s->exponent_bits = bit_count; } @@ -599,8 +623,6 @@ void ff_ac3_process_exponents(AC3EncodeContext *s) encode_exponents(s); - group_exponents(s); - emms_c(); } @@ -1095,6 +1117,8 @@ int ff_ac3_compute_bit_allocation(AC3EncodeContext *s) { count_frame_bits(s); + s->exponent_bits = count_exponent_bits(s); + bit_alloc_masking(s); return cbr_bit_allocation(s); diff --git a/libavcodec/ac3enc.h b/libavcodec/ac3enc.h index 6d57143a01..c1e69b101f 100644 --- a/libavcodec/ac3enc.h +++ b/libavcodec/ac3enc.h @@ -257,6 +257,8 @@ void ff_ac3_process_exponents(AC3EncodeContext *s); int ff_ac3_compute_bit_allocation(AC3EncodeContext *s); +void ff_ac3_group_exponents(AC3EncodeContext *s); + void ff_ac3_quantize_mantissas(AC3EncodeContext *s); void ff_ac3_output_frame(AC3EncodeContext *s, unsigned char *frame); diff --git a/libavcodec/ac3enc_template.c b/libavcodec/ac3enc_template.c index 103e7b1a96..dd1e48d1f8 100644 --- a/libavcodec/ac3enc_template.c +++ b/libavcodec/ac3enc_template.c @@ -463,6 +463,8 @@ int AC3_NAME(encode_frame)(AVCodecContext *avctx, unsigned char *frame, return ret; } + ff_ac3_group_exponents(s); + ff_ac3_quantize_mantissas(s); ff_ac3_output_frame(s, frame); |