diff options
Diffstat (limited to 'media/libstagefright/codecs/amrwbenc/src/residu.c')
-rw-r--r-- | media/libstagefright/codecs/amrwbenc/src/residu.c | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/media/libstagefright/codecs/amrwbenc/src/residu.c b/media/libstagefright/codecs/amrwbenc/src/residu.c new file mode 100644 index 0000000..b0c04b5 --- /dev/null +++ b/media/libstagefright/codecs/amrwbenc/src/residu.c @@ -0,0 +1,67 @@ +/* + ** Copyright 2003-2010, VisualOn, Inc. + ** + ** Licensed under the Apache License, Version 2.0 (the "License"); + ** you may not use this file except in compliance with the License. + ** You may obtain a copy of the License at + ** + ** http://www.apache.org/licenses/LICENSE-2.0 + ** + ** Unless required by applicable law or agreed to in writing, software + ** distributed under the License is distributed on an "AS IS" BASIS, + ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + ** See the License for the specific language governing permissions and + ** limitations under the License. + */ + +/*********************************************************************** +* File: residu.c * +* * +* Description: Compute the LPC residual by filtering * +* the input speech through A(z) * +* * +************************************************************************/ + +#include "typedef.h" +#include "basic_op.h" + +void Residu( + Word16 a[], /* (i) Q12 : prediction coefficients */ + Word16 x[], /* (i) : speech (values x[-m..-1] are needed */ + Word16 y[], /* (o) x2 : residual signal */ + Word16 lg /* (i) : size of filtering */ + ) +{ + Word16 i,*p1, *p2; + Word32 s; + for (i = 0; i < lg; i++) + { + p1 = a; + p2 = &x[i]; + s = vo_mult32((*p1++), (*p2--)); + s += vo_mult32((*p1++), (*p2--)); + s += vo_mult32((*p1++), (*p2--)); + s += vo_mult32((*p1++), (*p2--)); + s += vo_mult32((*p1++), (*p2--)); + s += vo_mult32((*p1++), (*p2--)); + s += vo_mult32((*p1++), (*p2--)); + s += vo_mult32((*p1++), (*p2--)); + s += vo_mult32((*p1++), (*p2--)); + s += vo_mult32((*p1++), (*p2--)); + s += vo_mult32((*p1++), (*p2--)); + s += vo_mult32((*p1++), (*p2--)); + s += vo_mult32((*p1++), (*p2--)); + s += vo_mult32((*p1++), (*p2--)); + s += vo_mult32((*p1++), (*p2--)); + s += vo_mult32((*p1++), (*p2--)); + s += vo_mult32((*p1), (*p2)); + + s = L_shl2(s, 5); + y[i] = extract_h(L_add(s, 0x8000)); + } + + return; +} + + + |