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streamline FLAC__fixed_compute_best_predictor_slow()

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This commit is contained in:
Josh Coalson
2001-05-18 18:49:19 +00:00
parent d80c18e4ac
commit eee20a5fdd
1 changed files with 6 additions and 11 deletions
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17
src/libFLAC/fixed.c
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@@ -80,7 +80,7 @@ unsigned FLAC__fixed_compute_best_predictor_slow(const int32 data[], unsigned da
int32 last_error_1 = data[-1] - data[-2];
int32 last_error_2 = last_error_1 - (data[-2] - data[-3]);
int32 last_error_3 = last_error_2 - (data[-2] - 2*data[-3] + data[-4]);
int32 error_0, error_1, error_2, error_3, error_4;
int32 error_0, save;
/* total_error_* are 64-bits to avoid overflow when encoding
* erratic signals when the bits-per-sample and blocksize are
* large.
@@ -89,16 +89,11 @@ unsigned FLAC__fixed_compute_best_predictor_slow(const int32 data[], unsigned da
unsigned i, order;
for(i = 0; i < data_len; i++) {
error_0 = data[i] ; total_error_0 += local_abs(error_0);
error_1 = error_0 - last_error_0; total_error_1 += local_abs(error_1);
error_2 = error_1 - last_error_1; total_error_2 += local_abs(error_2);
error_3 = error_2 - last_error_2; total_error_3 += local_abs(error_3);
error_4 = error_3 - last_error_3; total_error_4 += local_abs(error_4);
last_error_0 = error_0;
last_error_1 = error_1;
last_error_2 = error_2;
last_error_3 = error_3;
error = data[i] ; total_error_0 += local_abs(error); save = error;
error -= last_error_0; total_error_1 += local_abs(error); last_error_0 = save; save = error;
error -= last_error_1; total_error_2 += local_abs(error); last_error_1 = save; save = error;
error -= last_error_2; total_error_3 += local_abs(error); last_error_2 = save; save = error;
error -= last_error_3; total_error_4 += local_abs(error); last_error_3 = save;
}
if(total_error_0 < min(min(min(total_error_1, total_error_2), total_error_3), total_error_4))