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Code Issues Releases Activity

Move bit counts to AC3EncodeContext.

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Originally committed as revision 26007 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Justin Ruggles 2010-12-14 22:45:12 +00:00
parent 82ccbe6b27
commit 359c1d1926
1 changed files with 14 additions and 15 deletions
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29
libavcodec/ac3enc.c
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@ -93,6 +93,8 @@ typedef struct AC3EncodeContext {
int coarse_snr_offset; ///< coarse SNR offsets (csnroffst)
int fast_gain_code[AC3_MAX_CHANNELS]; ///< fast gain codes (signal-to-mask ratio) (fgaincod)
int fine_snr_offset[AC3_MAX_CHANNELS]; ///< fine SNR offsets (fsnroffst)
int frame_bits; ///< all frame bits except exponents and mantissas
int exponent_bits; ///< number of bits used for exponents
/* mantissa encoding */
int mant1_cnt, mant2_cnt, mant4_cnt; ///< mantissa counts for bap=1,2,4
@ -663,9 +665,8 @@ static void encode_exponents(AC3EncodeContext *s,
* Group exponents.
* 3 delta-encoded exponents are in each 7-bit group. The number of groups
* varies depending on exponent strategy and bandwidth.
* @return bits needed to encode the exponents
*/
static int group_exponents(AC3EncodeContext *s,
static void group_exponents(AC3EncodeContext *s,
uint8_t encoded_exp[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][AC3_MAX_COEFS],
uint8_t exp_strategy[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS],
uint8_t num_exp_groups[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS],
@ -715,7 +716,7 @@ static int group_exponents(AC3EncodeContext *s,
}
}
return bit_count;
s->exponent_bits = bit_count;
}
@ -723,9 +724,8 @@ static int group_exponents(AC3EncodeContext *s,
* Calculate final exponents from the supplied MDCT coefficients and exponent shift.
* Extract exponents from MDCT coefficients, calculate exponent strategies,
* and encode final exponents.
* @return bits needed to encode the exponents
*/
static int process_exponents(AC3EncodeContext *s,
static void process_exponents(AC3EncodeContext *s,
int32_t mdct_coef[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][AC3_MAX_COEFS],
int8_t exp_shift[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS],
uint8_t exp[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][AC3_MAX_COEFS],
@ -740,7 +740,7 @@ static int process_exponents(AC3EncodeContext *s,
encode_exponents(s, exp, exp_strategy, num_exp_groups, encoded_exp);
return group_exponents(s, encoded_exp, exp_strategy, num_exp_groups, grouped_exp);
group_exponents(s, encoded_exp, exp_strategy, num_exp_groups, grouped_exp);
}
@ -777,9 +777,8 @@ static void bit_alloc_init(AC3EncodeContext *s)
/**
* Count the bits used to encode the frame, minus exponents and mantissas.
* @return bit count
*/
static int count_frame_bits(AC3EncodeContext *s,
static void count_frame_bits(AC3EncodeContext *s,
uint8_t exp_strategy[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS])
{
static const int frame_bits_inc[8] = { 0, 0, 2, 2, 2, 4, 2, 4 };
@ -822,7 +821,7 @@ static int count_frame_bits(AC3EncodeContext *s,
/* CRC */
frame_bits += 16;
return frame_bits;
s->frame_bits = frame_bits;
}
@ -958,17 +957,17 @@ static int bit_alloc(AC3EncodeContext *s,
static int compute_bit_allocation(AC3EncodeContext *s,
uint8_t bap[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][AC3_MAX_COEFS],
uint8_t encoded_exp[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][AC3_MAX_COEFS],
uint8_t exp_strategy[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS],
int frame_bits)
uint8_t exp_strategy[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS])
{
int ch;
int frame_bits;
int coarse_snr_offset, fine_snr_offset;
uint8_t bap1[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][AC3_MAX_COEFS];
int16_t psd[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][AC3_MAX_COEFS];
int16_t mask[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][AC3_CRITICAL_BANDS];
/* count frame bits other than exponents and mantissas */
frame_bits += count_frame_bits(s, exp_strategy);
count_frame_bits(s, exp_strategy);
/* calculate psd and masking curve before doing bit allocation */
bit_alloc_masking(s, encoded_exp, exp_strategy, psd, mask);
@ -976,6 +975,7 @@ static int compute_bit_allocation(AC3EncodeContext *s,
/* now the big work begins : do the bit allocation. Modify the snr
offset until we can pack everything in the requested frame size */
frame_bits = s->frame_bits + s->exponent_bits;
coarse_snr_offset = s->coarse_snr_offset;
while (coarse_snr_offset >= 0 &&
bit_alloc(s, mask, psd, bap, frame_bits, coarse_snr_offset, 0) < 0)
@ -1442,7 +1442,6 @@ static int ac3_encode_frame(AVCodecContext *avctx,
uint8_t bap[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][AC3_MAX_COEFS];
int8_t exp_shift[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS];
uint16_t qmant[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][AC3_MAX_COEFS];
int frame_bits;
int ret;
if (s->bit_alloc.sr_code == 1)
@ -1452,10 +1451,10 @@ static int ac3_encode_frame(AVCodecContext *avctx,
apply_mdct(s, planar_samples, exp_shift, mdct_coef);
frame_bits = process_exponents(s, mdct_coef, exp_shift, exp, exp_strategy,
process_exponents(s, mdct_coef, exp_shift, exp, exp_strategy,
encoded_exp, num_exp_groups, grouped_exp);
ret = compute_bit_allocation(s, bap, encoded_exp, exp_strategy, frame_bits);
ret = compute_bit_allocation(s, bap, encoded_exp, exp_strategy);
if (ret) {
av_log(avctx, AV_LOG_ERROR, "Bit allocation failed. Try increasing the bitrate.\n");
return ret;