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| author | Jean-Marc Valin <jmvalin@jmvalin.ca> | 2011-10-27 13:51:21 -0400 |
|---|---|---|
| committer | Jean-Marc Valin <jmvalin@jmvalin.ca> | 2011-10-27 13:51:21 -0400 |
| commit | 4a7027b27e2d962dedc63360a45db5ff74dc1131 (patch) | |
| tree | bca307bc6c1889b86afa24f58bca1b69c98e6835 /silk/LPC_analysis_filter.c | |
| parent | e6a0be8ee6a0675dc7c959a0c3cf9d3f7219b682 (diff) | |
| download | opus-4a7027b27e2d962dedc63360a45db5ff74dc1131.tar.gz | |
Allow wrap-around in silk_LPC_analysis_filter()
Diffstat (limited to 'silk/LPC_analysis_filter.c')
| -rw-r--r-- | silk/LPC_analysis_filter.c | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/silk/LPC_analysis_filter.c b/silk/LPC_analysis_filter.c index a8d1c333..5fc4349b 100644 --- a/silk/LPC_analysis_filter.c +++ b/silk/LPC_analysis_filter.c @@ -58,18 +58,20 @@ void silk_LPC_analysis_filter( in_ptr = &in[ ix - 1 ]; out32_Q12 = silk_SMULBB( in_ptr[ 0 ], B[ 0 ] ); - out32_Q12 = silk_SMLABB( out32_Q12, in_ptr[ -1 ], B[ 1 ] ); - out32_Q12 = silk_SMLABB( out32_Q12, in_ptr[ -2 ], B[ 2 ] ); - out32_Q12 = silk_SMLABB( out32_Q12, in_ptr[ -3 ], B[ 3 ] ); - out32_Q12 = silk_SMLABB( out32_Q12, in_ptr[ -4 ], B[ 4 ] ); - out32_Q12 = silk_SMLABB( out32_Q12, in_ptr[ -5 ], B[ 5 ] ); + /* Allowing wrap around so that two wraps can cancel each other. The rare + cases where the result wraps around can only be triggered by invalid streams*/ + out32_Q12 = silk_SMLABB_ovflw( out32_Q12, in_ptr[ -1 ], B[ 1 ] ); + out32_Q12 = silk_SMLABB_ovflw( out32_Q12, in_ptr[ -2 ], B[ 2 ] ); + out32_Q12 = silk_SMLABB_ovflw( out32_Q12, in_ptr[ -3 ], B[ 3 ] ); + out32_Q12 = silk_SMLABB_ovflw( out32_Q12, in_ptr[ -4 ], B[ 4 ] ); + out32_Q12 = silk_SMLABB_ovflw( out32_Q12, in_ptr[ -5 ], B[ 5 ] ); for( j = 6; j < d; j += 2 ) { - out32_Q12 = silk_SMLABB( out32_Q12, in_ptr[ -j ], B[ j ] ); - out32_Q12 = silk_SMLABB( out32_Q12, in_ptr[ -j - 1 ], B[ j + 1 ] ); + out32_Q12 = silk_SMLABB_ovflw( out32_Q12, in_ptr[ -j ], B[ j ] ); + out32_Q12 = silk_SMLABB_ovflw( out32_Q12, in_ptr[ -j - 1 ], B[ j + 1 ] ); } /* Subtract prediction */ - out32_Q12 = silk_SUB32( silk_LSHIFT( (opus_int32)in_ptr[ 1 ], 12 ), out32_Q12 ); + out32_Q12 = silk_SUB32_ovflw( silk_LSHIFT( (opus_int32)in_ptr[ 1 ], 12 ), out32_Q12 ); /* Scale to Q0 */ out32 = silk_RSHIFT_ROUND( out32_Q12, 12 ); |