From 427048f0c1faa90b8950d8d719b38c8883dda818 Mon Sep 17 00:00:00 2001 From: Josh Coalson Date: Tue, 27 Aug 2002 05:44:57 +0000 Subject: [PATCH] streamline the residual energy calculation --- src/libFLAC/fixed.c | 43 ++++++++++++++++++++++++++++--------------- 1 file changed, 28 insertions(+), 15 deletions(-) diff --git a/src/libFLAC/fixed.c b/src/libFLAC/fixed.c index 1fb3f063..f1d76753 100644 --- a/src/libFLAC/fixed.c +++ b/src/libFLAC/fixed.c @@ -65,11 +65,19 @@ unsigned FLAC__fixed_compute_best_predictor(const FLAC__int32 data[], unsigned d else order = 4; - residual_bits_per_sample[0] = (FLAC__real)((data_len > 0 && total_error_0 > 0) ? log(M_LN2 * (double)total_error_0 / (double) data_len) / M_LN2 : 0.0); - residual_bits_per_sample[1] = (FLAC__real)((data_len > 0 && total_error_1 > 0) ? log(M_LN2 * (double)total_error_1 / (double) data_len) / M_LN2 : 0.0); - residual_bits_per_sample[2] = (FLAC__real)((data_len > 0 && total_error_2 > 0) ? log(M_LN2 * (double)total_error_2 / (double) data_len) / M_LN2 : 0.0); - residual_bits_per_sample[3] = (FLAC__real)((data_len > 0 && total_error_3 > 0) ? log(M_LN2 * (double)total_error_3 / (double) data_len) / M_LN2 : 0.0); - residual_bits_per_sample[4] = (FLAC__real)((data_len > 0 && total_error_4 > 0) ? log(M_LN2 * (double)total_error_4 / (double) data_len) / M_LN2 : 0.0); + /* Estimate the expected number of bits per residual signal sample. */ + /* 'total_error*' is linearly related to the variance of the residual */ + /* signal, so we use it directly to compute E(|x|) */ + FLAC__ASSERT(data_len > 0 || total_error_0 == 0); + FLAC__ASSERT(data_len > 0 || total_error_1 == 0); + FLAC__ASSERT(data_len > 0 || total_error_2 == 0); + FLAC__ASSERT(data_len > 0 || total_error_3 == 0); + FLAC__ASSERT(data_len > 0 || total_error_4 == 0); + residual_bits_per_sample[0] = (FLAC__real)((total_error_0 > 0) ? log(M_LN2 * (double)total_error_0 / (double)data_len) / M_LN2 : 0.0); + residual_bits_per_sample[1] = (FLAC__real)((total_error_1 > 0) ? log(M_LN2 * (double)total_error_1 / (double)data_len) / M_LN2 : 0.0); + residual_bits_per_sample[2] = (FLAC__real)((total_error_2 > 0) ? log(M_LN2 * (double)total_error_2 / (double)data_len) / M_LN2 : 0.0); + residual_bits_per_sample[3] = (FLAC__real)((total_error_3 > 0) ? log(M_LN2 * (double)total_error_3 / (double)data_len) / M_LN2 : 0.0); + residual_bits_per_sample[4] = (FLAC__real)((total_error_4 > 0) ? log(M_LN2 * (double)total_error_4 / (double)data_len) / M_LN2 : 0.0); return order; } @@ -110,19 +118,24 @@ unsigned FLAC__fixed_compute_best_predictor_wide(const FLAC__int32 data[], unsig /* Estimate the expected number of bits per residual signal sample. */ /* 'total_error*' is linearly related to the variance of the residual */ /* signal, so we use it directly to compute E(|x|) */ + FLAC__ASSERT(data_len > 0 || total_error_0 == 0); + FLAC__ASSERT(data_len > 0 || total_error_1 == 0); + FLAC__ASSERT(data_len > 0 || total_error_2 == 0); + FLAC__ASSERT(data_len > 0 || total_error_3 == 0); + FLAC__ASSERT(data_len > 0 || total_error_4 == 0); #if defined _MSC_VER || defined __MINGW32__ /* with VC++ you have to spoon feed it the casting */ - residual_bits_per_sample[0] = (FLAC__real)((data_len > 0 && total_error_0 > 0) ? log(M_LN2 * (double)(FLAC__int64)total_error_0 / (double) data_len) / M_LN2 : 0.0); - residual_bits_per_sample[1] = (FLAC__real)((data_len > 0 && total_error_1 > 0) ? log(M_LN2 * (double)(FLAC__int64)total_error_1 / (double) data_len) / M_LN2 : 0.0); - residual_bits_per_sample[2] = (FLAC__real)((data_len > 0 && total_error_2 > 0) ? log(M_LN2 * (double)(FLAC__int64)total_error_2 / (double) data_len) / M_LN2 : 0.0); - residual_bits_per_sample[3] = (FLAC__real)((data_len > 0 && total_error_3 > 0) ? log(M_LN2 * (double)(FLAC__int64)total_error_3 / (double) data_len) / M_LN2 : 0.0); - residual_bits_per_sample[4] = (FLAC__real)((data_len > 0 && total_error_4 > 0) ? log(M_LN2 * (double)(FLAC__int64)total_error_4 / (double) data_len) / M_LN2 : 0.0); + residual_bits_per_sample[0] = (FLAC__real)((total_error_0 > 0) ? log(M_LN2 * (double)(FLAC__int64)total_error_0 / (double)data_len) / M_LN2 : 0.0); + residual_bits_per_sample[1] = (FLAC__real)((total_error_1 > 0) ? log(M_LN2 * (double)(FLAC__int64)total_error_1 / (double)data_len) / M_LN2 : 0.0); + residual_bits_per_sample[2] = (FLAC__real)((total_error_2 > 0) ? log(M_LN2 * (double)(FLAC__int64)total_error_2 / (double)data_len) / M_LN2 : 0.0); + residual_bits_per_sample[3] = (FLAC__real)((total_error_3 > 0) ? log(M_LN2 * (double)(FLAC__int64)total_error_3 / (double)data_len) / M_LN2 : 0.0); + residual_bits_per_sample[4] = (FLAC__real)((total_error_4 > 0) ? log(M_LN2 * (double)(FLAC__int64)total_error_4 / (double)data_len) / M_LN2 : 0.0); #else - residual_bits_per_sample[0] = (FLAC__real)((data_len > 0 && total_error_0 > 0) ? log(M_LN2 * (double)total_error_0 / (double) data_len) / M_LN2 : 0.0); - residual_bits_per_sample[1] = (FLAC__real)((data_len > 0 && total_error_1 > 0) ? log(M_LN2 * (double)total_error_1 / (double) data_len) / M_LN2 : 0.0); - residual_bits_per_sample[2] = (FLAC__real)((data_len > 0 && total_error_2 > 0) ? log(M_LN2 * (double)total_error_2 / (double) data_len) / M_LN2 : 0.0); - residual_bits_per_sample[3] = (FLAC__real)((data_len > 0 && total_error_3 > 0) ? log(M_LN2 * (double)total_error_3 / (double) data_len) / M_LN2 : 0.0); - residual_bits_per_sample[4] = (FLAC__real)((data_len > 0 && total_error_4 > 0) ? log(M_LN2 * (double)total_error_4 / (double) data_len) / M_LN2 : 0.0); + residual_bits_per_sample[0] = (FLAC__real)((total_error_0 > 0) ? log(M_LN2 * (double)total_error_0 / (double)data_len) / M_LN2 : 0.0); + residual_bits_per_sample[1] = (FLAC__real)((total_error_1 > 0) ? log(M_LN2 * (double)total_error_1 / (double)data_len) / M_LN2 : 0.0); + residual_bits_per_sample[2] = (FLAC__real)((total_error_2 > 0) ? log(M_LN2 * (double)total_error_2 / (double)data_len) / M_LN2 : 0.0); + residual_bits_per_sample[3] = (FLAC__real)((total_error_3 > 0) ? log(M_LN2 * (double)total_error_3 / (double)data_len) / M_LN2 : 0.0); + residual_bits_per_sample[4] = (FLAC__real)((total_error_4 > 0) ? log(M_LN2 * (double)total_error_4 / (double)data_len) / M_LN2 : 0.0); #endif return order;