1 /*=============================================================================
3 // This software has been released under the terms of the GNU General Public
4 // license. See http://www.gnu.org/copyleft/gpl.html for details.
6 // Copyright 2001 Anders Johansson ajh@atri.curtin.edu.au
8 //=============================================================================
11 #if !defined MPLAYER_DSP_H
12 # error Never use filter.h directly; include dsp.h instead.
15 #ifndef MPLAYER_FILTER_H
16 #define MPLAYER_FILTER_H
19 // Design and implementation of different types of digital filters
22 // Flags used for filter design
24 // Filter characteristics
25 #define LP 0x00010000 // Low pass
26 #define HP 0x00020000 // High pass
27 #define BP 0x00040000 // Band pass
28 #define BS 0x00080000 // Band stop
29 #define TYPE_MASK 0x000F0000
32 #define BOXCAR 0x00000001
33 #define TRIANG 0x00000002
34 #define HAMMING 0x00000004
35 #define HANNING 0x00000008
36 #define BLACKMAN 0x00000010
37 #define FLATTOP 0x00000011
38 #define KAISER 0x00000012
39 #define WINDOW_MASK 0x0000001F
41 // Parallel filter design
42 #define FWD 0x00000001 // Forward indexing of polyphase filter
43 #define REW 0x00000002 // Reverse indexing of polyphase filter
44 #define ODD 0x00000010 // Make filter HP
47 extern FLOAT_TYPE
af_filter_fir(unsigned int n
, const FLOAT_TYPE
* w
, const FLOAT_TYPE
* x
);
49 extern FLOAT_TYPE
* af_filter_pfir(unsigned int n
, unsigned int k
,
50 unsigned int xi
, const FLOAT_TYPE
** w
,
51 const FLOAT_TYPE
** x
, FLOAT_TYPE
* y
,
54 //extern int af_filter_updateq(unsigned int n, unsigned int xi,
55 // FLOAT_TYPE* xq, FLOAT_TYPE* in);
56 extern int af_filter_updatepq(unsigned int n
, unsigned int k
, unsigned int xi
,
57 FLOAT_TYPE
** xq
, const FLOAT_TYPE
* in
, unsigned int s
);
59 extern int af_filter_design_fir(unsigned int n
, FLOAT_TYPE
* w
, const FLOAT_TYPE
* fc
,
60 unsigned int flags
, FLOAT_TYPE opt
);
62 extern int af_filter_design_pfir(unsigned int n
, unsigned int k
, const FLOAT_TYPE
* w
,
63 FLOAT_TYPE
** pw
, FLOAT_TYPE g
,
66 extern int af_filter_szxform(const FLOAT_TYPE
* a
, const FLOAT_TYPE
* b
, FLOAT_TYPE Q
,
67 FLOAT_TYPE fc
, FLOAT_TYPE fs
, FLOAT_TYPE
*k
,
70 /* Add new data to circular queue designed to be used with a FIR
71 filter. xq is the circular queue, in pointing at the new sample, xi
72 current index for xq and n the length of the filter. xq must be n*2
75 #define af_filter_updateq(n,xi,xq,in)\
76 xq[xi]=(xq)[(xi)+(n)]=*(in);\
79 #endif /* MPLAYER_FILTER_H */