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Only calculate num_exp_groups once.

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Originally committed as revision 26000 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Justin Ruggles
2010-12-14 14:53:33 +00:00
parent dc0bc0f84e
commit d3325d555b
1 changed files with 8 additions and 5 deletions
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13
libavcodec/ac3enc.c
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@@ -575,13 +575,15 @@ static void exponent_min(uint8_t exp[AC3_MAX_COEFS], uint8_t exp1[AC3_MAX_COEFS]
*/
static void encode_exponents_blk_ch(uint8_t encoded_exp[AC3_MAX_COEFS],
uint8_t exp[AC3_MAX_COEFS],
int nb_exps, int exp_strategy)
int nb_exps, int exp_strategy,
uint8_t *num_exp_groups)
{
int group_size, nb_groups, i, j, k, exp_min;
uint8_t exp1[AC3_MAX_COEFS];
group_size = exp_strategy + (exp_strategy == EXP_D45);
nb_groups = ((nb_exps + (group_size * 3) - 4) / (3 * group_size)) * 3;
*num_exp_groups = (nb_exps + (group_size * 3) - 4) / (3 * group_size);
nb_groups = *num_exp_groups * 3;
/* for each group, compute the minimum exponent */
exp1[0] = exp[0]; /* DC exponent is handled separately */
@@ -628,6 +630,7 @@ static void encode_exponents_blk_ch(uint8_t encoded_exp[AC3_MAX_COEFS],
static void encode_exponents(AC3EncodeContext *s,
uint8_t 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],
uint8_t encoded_exp[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][AC3_MAX_COEFS])
{
int blk, blk1, blk2, ch;
@@ -643,7 +646,8 @@ static void encode_exponents(AC3EncodeContext *s,
}
encode_exponents_blk_ch(encoded_exp[blk][ch],
exp[blk][ch], s->nb_coefs[ch],
exp_strategy[blk][ch]);
exp_strategy[blk][ch],
&num_exp_groups[blk][ch]);
/* copy encoded exponents for reuse case */
for (blk2 = blk+1; blk2 < blk1; blk2++) {
memcpy(encoded_exp[blk2][ch], encoded_exp[blk][ch],
@@ -681,7 +685,6 @@ static int group_exponents(AC3EncodeContext *s,
continue;
}
group_size = exp_strategy[blk][ch] + (exp_strategy[blk][ch] == EXP_D45);
num_exp_groups[blk][ch] = (s->nb_coefs[ch] + (group_size * 3) - 4) / (3 * group_size);
bit_count += 4 + (num_exp_groups[blk][ch] * 7);
p = encoded_exp[blk][ch];
@@ -735,7 +738,7 @@ static int process_exponents(AC3EncodeContext *s,
compute_exp_strategy(s, exp_strategy, exp);
encode_exponents(s, exp, exp_strategy, encoded_exp);
encode_exponents(s, exp, exp_strategy, num_exp_groups, encoded_exp);
return group_exponents(s, encoded_exp, exp_strategy, num_exp_groups, grouped_exp);
}