diff options
Diffstat (limited to 'codecs/ilbc/hpInput.c')
-rwxr-xr-x | codecs/ilbc/hpInput.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/codecs/ilbc/hpInput.c b/codecs/ilbc/hpInput.c new file mode 100755 index 000000000..1599c2923 --- /dev/null +++ b/codecs/ilbc/hpInput.c @@ -0,0 +1,58 @@ + +/****************************************************************** + + iLBC Speech Coder ANSI-C Source Code + + hpInput.c + + Copyright (c) 2001, + Global IP Sound AB. + All rights reserved. + +******************************************************************/ + +#include "constants.h" + +/*----------------------------------------------------------------* + * Input high-pass filter + *---------------------------------------------------------------*/ + +void hpInput( + float *In, /* (i) vector to filter */ + int len, /* (i) length of vector to filter */ + float *Out, /* (o) the resulting filtered vector */ + float *mem /* (i/o) the filter state */ +){ + int i; + float *pi, *po; + + /* all-zero section*/ + + pi = &In[0]; + po = &Out[0]; + for (i=0; i<len; i++) { + *po = hpi_zero_coefsTbl[0] * (*pi); + *po += hpi_zero_coefsTbl[1] * mem[0]; + *po += hpi_zero_coefsTbl[2] * mem[1]; + + mem[1] = mem[0]; + mem[0] = *pi; + po++; + pi++; + + } + + /* all-pole section*/ + + po = &Out[0]; + for (i=0; i<len; i++) { + *po -= hpi_pole_coefsTbl[1] * mem[2]; + *po -= hpi_pole_coefsTbl[2] * mem[3]; + + mem[3] = mem[2]; + mem[2] = *po; + po++; + } +} + + |