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author | Koen Vos <koenvos@users.noreply.github.com> | 2016-06-02 23:03:27 +0800 |
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committer | Jean-Marc Valin <jmvalin@jmvalin.ca> | 2016-07-19 16:11:19 -0400 |
commit | d60816f76d2efcb5058874c9bcd440b79781ce68 (patch) | |
tree | 5b68336f492e01ccc3012e0e5b81aa30e9667141 | |
parent | 3af77bf4256cc0c69c99b3c384f6b47e5c9b3fd6 (diff) | |
download | opus-d60816f76d2efcb5058874c9bcd440b79781ce68.tar.gz |
comment about reduced codelength component in LTP quantizer error metric
-rw-r--r-- | silk/VQ_WMat_EC.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/silk/VQ_WMat_EC.c b/silk/VQ_WMat_EC.c index 2f3aa82a..8b5ebde8 100644 --- a/silk/VQ_WMat_EC.c +++ b/silk/VQ_WMat_EC.c @@ -65,7 +65,7 @@ void silk_VQ_WMat_EC_c( *ind = 0; for( k = 0; k < L; k++ ) { /* Weighted rate */ - /* Quantization error: 1 - 2* xX * cb + cb' * XX * cb */ + /* Quantization error: 1 - 2 * xX * cb + cb' * XX * cb */ sum1_Q15 = SILK_FIX_CONST( 1.001, 15 ); /* first row of XX_Q17 */ @@ -107,7 +107,8 @@ void silk_VQ_WMat_EC_c( if( sum1_Q15 >= 0 ) { /* Translate residual energy to bits using high-rate assumption (6 dB ==> 1 bit/sample) */ bits_res_Q8 = silk_SMULBB( subfr_len, silk_lin2log( sum1_Q15 ) - (15 << 7) ); - bits_tot_Q8 = silk_ADD_LSHIFT32( bits_res_Q8, cl_Q5[ k ], 2 ); + /* In the following line we reduce the codelength component by half ("-1"); seems to slghtly improve quality */ + bits_tot_Q8 = silk_ADD_LSHIFT32( bits_res_Q8, cl_Q5[ k ], 3-1 ); if( bits_tot_Q8 <= *rate_dist_Q8 ) { *rate_dist_Q8 = bits_tot_Q8; *res_nrg_Q15 = sum1_Q15; |