2 * HRTF utility for producing and demonstrating the process of creating an
3 * OpenAL Soft compatible HRIR data set.
5 * Copyright (C) 2011-2017 Christopher Fitzgerald
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License along
18 * with this program; if not, write to the Free Software Foundation, Inc.,
19 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
21 * Or visit: http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
23 * --------------------------------------------------------------------------
25 * A big thanks goes out to all those whose work done in the field of
26 * binaural sound synthesis using measured HRTFs makes this utility and the
27 * OpenAL Soft implementation possible.
29 * The algorithm for diffuse-field equalization was adapted from the work
30 * done by Rio Emmanuel and Larcher Veronique of IRCAM and Bill Gardner of
31 * MIT Media Laboratory. It operates as follows:
33 * 1. Take the FFT of each HRIR and only keep the magnitude responses.
34 * 2. Calculate the diffuse-field power-average of all HRIRs weighted by
35 * their contribution to the total surface area covered by their
37 * 3. Take the diffuse-field average and limit its magnitude range.
38 * 4. Equalize the responses by using the inverse of the diffuse-field
40 * 5. Reconstruct the minimum-phase responses.
41 * 5. Zero the DC component.
42 * 6. IFFT the result and truncate to the desired-length minimum-phase FIR.
44 * The spherical head algorithm for calculating propagation delay was adapted
47 * Modeling Interaural Time Difference Assuming a Spherical Head
49 * Music 150, Musical Acoustics, Stanford University
52 * The formulae for calculating the Kaiser window metrics are from the
55 * Discrete-Time Signal Processing
56 * Alan V. Oppenheim and Ronald W. Schafer
57 * Prentice-Hall Signal Processing Series
74 // Rely (if naively) on OpenAL's header for the types used for serialization.
79 #define M_PI (3.14159265358979323846)
83 #define HUGE_VAL (1.0 / 0.0)
86 // The epsilon used to maintain signal stability.
87 #define EPSILON (1e-9)
89 // Constants for accessing the token reader's ring buffer.
90 #define TR_RING_BITS (16)
91 #define TR_RING_SIZE (1 << TR_RING_BITS)
92 #define TR_RING_MASK (TR_RING_SIZE - 1)
94 // The token reader's load interval in bytes.
95 #define TR_LOAD_SIZE (TR_RING_SIZE >> 2)
97 // The maximum identifier length used when processing the data set
99 #define MAX_IDENT_LEN (16)
101 // The maximum path length used when processing filenames.
102 #define MAX_PATH_LEN (256)
104 // The limits for the sample 'rate' metric in the data set definition and for
106 #define MIN_RATE (32000)
107 #define MAX_RATE (96000)
109 // The limits for the HRIR 'points' metric in the data set definition.
110 #define MIN_POINTS (16)
111 #define MAX_POINTS (8192)
113 // The limits to the number of 'azimuths' listed in the data set definition.
114 #define MIN_EV_COUNT (5)
115 #define MAX_EV_COUNT (128)
117 // The limits for each of the 'azimuths' listed in the data set definition.
118 #define MIN_AZ_COUNT (1)
119 #define MAX_AZ_COUNT (128)
121 // The limits for the listener's head 'radius' in the data set definition.
122 #define MIN_RADIUS (0.05)
123 #define MAX_RADIUS (0.15)
125 // The limits for the 'distance' from source to listener in the definition
127 #define MIN_DISTANCE (0.5)
128 #define MAX_DISTANCE (2.5)
130 // The maximum number of channels that can be addressed for a WAVE file
131 // source listed in the data set definition.
132 #define MAX_WAVE_CHANNELS (65535)
134 // The limits to the byte size for a binary source listed in the definition
136 #define MIN_BIN_SIZE (2)
137 #define MAX_BIN_SIZE (4)
139 // The minimum number of significant bits for binary sources listed in the
140 // data set definition. The maximum is calculated from the byte size.
141 #define MIN_BIN_BITS (16)
143 // The limits to the number of significant bits for an ASCII source listed in
144 // the data set definition.
145 #define MIN_ASCII_BITS (16)
146 #define MAX_ASCII_BITS (32)
148 // The limits to the FFT window size override on the command line.
149 #define MIN_FFTSIZE (65536)
150 #define MAX_FFTSIZE (131072)
152 // The limits to the equalization range limit on the command line.
153 #define MIN_LIMIT (2.0)
154 #define MAX_LIMIT (120.0)
156 // The limits to the truncation window size on the command line.
157 #define MIN_TRUNCSIZE (16)
158 #define MAX_TRUNCSIZE (512)
160 // The limits to the custom head radius on the command line.
161 #define MIN_CUSTOM_RADIUS (0.05)
162 #define MAX_CUSTOM_RADIUS (0.15)
164 // The truncation window size must be a multiple of the below value to allow
165 // for vectorized convolution.
166 #define MOD_TRUNCSIZE (8)
168 // The defaults for the command line options.
169 #define DEFAULT_FFTSIZE (65536)
170 #define DEFAULT_EQUALIZE (1)
171 #define DEFAULT_SURFACE (1)
172 #define DEFAULT_LIMIT (24.0)
173 #define DEFAULT_TRUNCSIZE (32)
174 #define DEFAULT_HEAD_MODEL (HM_DATASET)
175 #define DEFAULT_CUSTOM_RADIUS (0.0)
177 // The four-character-codes for RIFF/RIFX WAVE file chunks.
178 #define FOURCC_RIFF (0x46464952) // 'RIFF'
179 #define FOURCC_RIFX (0x58464952) // 'RIFX'
180 #define FOURCC_WAVE (0x45564157) // 'WAVE'
181 #define FOURCC_FMT (0x20746D66) // 'fmt '
182 #define FOURCC_DATA (0x61746164) // 'data'
183 #define FOURCC_LIST (0x5453494C) // 'LIST'
184 #define FOURCC_WAVL (0x6C766177) // 'wavl'
185 #define FOURCC_SLNT (0x746E6C73) // 'slnt'
187 // The supported wave formats.
188 #define WAVE_FORMAT_PCM (0x0001)
189 #define WAVE_FORMAT_IEEE_FLOAT (0x0003)
190 #define WAVE_FORMAT_EXTENSIBLE (0xFFFE)
192 // The maximum propagation delay value supported by OpenAL Soft.
193 #define MAX_HRTD (63.0)
195 // The OpenAL Soft HRTF format marker. It stands for minimum-phase head
196 // response protocol 01.
197 #define MHR_FORMAT ("MinPHR01")
199 #define MHR_FORMAT_EXPERIMENTAL ("MinPHRTEMPDONOTUSE")
201 // Sample and channel type enum values
202 typedef enum SampleTypeT
{
207 typedef enum ChannelTypeT
{
212 // Byte order for the serialization routines.
213 typedef enum ByteOrderT
{
219 // Source format for the references listed in the data set definition.
220 typedef enum SourceFormatT
{
222 SF_WAVE
, // RIFF/RIFX WAVE file.
223 SF_BIN_LE
, // Little-endian binary file.
224 SF_BIN_BE
, // Big-endian binary file.
225 SF_ASCII
// ASCII text file.
228 // Element types for the references listed in the data set definition.
229 typedef enum ElementTypeT
{
231 ET_INT
, // Integer elements.
232 ET_FP
// Floating-point elements.
235 // Head model used for calculating the impulse delays.
236 typedef enum HeadModelT
{
238 HM_DATASET
, // Measure the onset from the dataset.
239 HM_SPHERE
// Calculate the onset using a spherical head model.
242 // Desired output format from the command line.
243 typedef enum OutputFormatT
{
245 OF_MHR
// OpenAL Soft MHR data set file.
248 // Unsigned integer type.
249 typedef unsigned int uint
;
251 // Serialization types. The trailing digit indicates the number of bits.
252 typedef ALubyte uint8
;
254 typedef ALuint uint32
;
255 typedef ALuint64SOFT uint64
;
257 // Token reader state for parsing the data set definition.
258 typedef struct TokenReaderT
{
263 char mRing
[TR_RING_SIZE
];
268 // Source reference state used when loading sources.
269 typedef struct SourceRefT
{
270 SourceFormatT mFormat
;
277 char mPath
[MAX_PATH_LEN
+1];
280 // The HRIR metrics and data set used when loading, processing, and storing
281 // the resulting HRTF.
282 typedef struct HrirDataT
{
284 SampleTypeT mSampleType
;
285 ChannelTypeT mChannelType
;
292 uint mAzCount
[MAX_EV_COUNT
];
293 uint mEvOffset
[MAX_EV_COUNT
];
301 // The resampler metrics and FIR filter.
302 typedef struct ResamplerT
{
308 /****************************************
309 *** Complex number type and routines ***
310 ****************************************/
316 static Complex
MakeComplex(double r
, double i
)
318 Complex c
= { r
, i
};
322 static Complex
c_add(Complex a
, Complex b
)
325 r
.Real
= a
.Real
+ b
.Real
;
326 r
.Imag
= a
.Imag
+ b
.Imag
;
330 static Complex
c_sub(Complex a
, Complex b
)
333 r
.Real
= a
.Real
- b
.Real
;
334 r
.Imag
= a
.Imag
- b
.Imag
;
338 static Complex
c_mul(Complex a
, Complex b
)
341 r
.Real
= a
.Real
*b
.Real
- a
.Imag
*b
.Imag
;
342 r
.Imag
= a
.Imag
*b
.Real
+ a
.Real
*b
.Imag
;
346 static double c_abs(Complex a
)
348 return sqrt(a
.Real
*a
.Real
+ a
.Imag
*a
.Imag
);
351 static Complex
c_exp(Complex a
)
354 double e
= exp(a
.Real
);
355 r
.Real
= e
* cos(a
.Imag
);
356 r
.Imag
= e
* sin(a
.Imag
);
360 /*****************************
361 *** Token reader routines ***
362 *****************************/
364 /* Whitespace is not significant. It can process tokens as identifiers, numbers
365 * (integer and floating-point), strings, and operators. Strings must be
366 * encapsulated by double-quotes and cannot span multiple lines.
369 // Setup the reader on the given file. The filename can be NULL if no error
370 // output is desired.
371 static void TrSetup(FILE *fp
, const char *filename
, TokenReaderT
*tr
)
373 const char *name
= NULL
;
377 const char *slash
= strrchr(filename
, '/');
380 const char *bslash
= strrchr(slash
+1, '\\');
381 if(bslash
) name
= bslash
+1;
386 const char *bslash
= strrchr(filename
, '\\');
387 if(bslash
) name
= bslash
+1;
388 else name
= filename
;
400 // Prime the reader's ring buffer, and return a result indicating that there
401 // is text to process.
402 static int TrLoad(TokenReaderT
*tr
)
404 size_t toLoad
, in
, count
;
406 toLoad
= TR_RING_SIZE
- (tr
->mIn
- tr
->mOut
);
407 if(toLoad
>= TR_LOAD_SIZE
&& !feof(tr
->mFile
))
409 // Load TR_LOAD_SIZE (or less if at the end of the file) per read.
410 toLoad
= TR_LOAD_SIZE
;
411 in
= tr
->mIn
&TR_RING_MASK
;
412 count
= TR_RING_SIZE
- in
;
415 tr
->mIn
+= fread(&tr
->mRing
[in
], 1, count
, tr
->mFile
);
416 tr
->mIn
+= fread(&tr
->mRing
[0], 1, toLoad
-count
, tr
->mFile
);
419 tr
->mIn
+= fread(&tr
->mRing
[in
], 1, toLoad
, tr
->mFile
);
421 if(tr
->mOut
>= TR_RING_SIZE
)
423 tr
->mOut
-= TR_RING_SIZE
;
424 tr
->mIn
-= TR_RING_SIZE
;
427 if(tr
->mIn
> tr
->mOut
)
432 // Error display routine. Only displays when the base name is not NULL.
433 static void TrErrorVA(const TokenReaderT
*tr
, uint line
, uint column
, const char *format
, va_list argPtr
)
437 fprintf(stderr
, "Error (%s:%u:%u): ", tr
->mName
, line
, column
);
438 vfprintf(stderr
, format
, argPtr
);
441 // Used to display an error at a saved line/column.
442 static void TrErrorAt(const TokenReaderT
*tr
, uint line
, uint column
, const char *format
, ...)
446 va_start(argPtr
, format
);
447 TrErrorVA(tr
, line
, column
, format
, argPtr
);
451 // Used to display an error at the current line/column.
452 static void TrError(const TokenReaderT
*tr
, const char *format
, ...)
456 va_start(argPtr
, format
);
457 TrErrorVA(tr
, tr
->mLine
, tr
->mColumn
, format
, argPtr
);
461 // Skips to the next line.
462 static void TrSkipLine(TokenReaderT
*tr
)
468 ch
= tr
->mRing
[tr
->mOut
&TR_RING_MASK
];
480 // Skips to the next token.
481 static int TrSkipWhitespace(TokenReaderT
*tr
)
487 ch
= tr
->mRing
[tr
->mOut
&TR_RING_MASK
];
507 // Get the line and/or column of the next token (or the end of input).
508 static void TrIndication(TokenReaderT
*tr
, uint
*line
, uint
*column
)
510 TrSkipWhitespace(tr
);
511 if(line
) *line
= tr
->mLine
;
512 if(column
) *column
= tr
->mColumn
;
515 // Checks to see if a token is the given operator. It does not display any
516 // errors and will not proceed to the next token.
517 static int TrIsOperator(TokenReaderT
*tr
, const char *op
)
522 if(!TrSkipWhitespace(tr
))
526 while(op
[len
] != '\0' && out
< tr
->mIn
)
528 ch
= tr
->mRing
[out
&TR_RING_MASK
];
529 if(ch
!= op
[len
]) break;
538 /* The TrRead*() routines obtain the value of a matching token type. They
539 * display type, form, and boundary errors and will proceed to the next
543 // Reads and validates an identifier token.
544 static int TrReadIdent(TokenReaderT
*tr
, const uint maxLen
, char *ident
)
550 if(TrSkipWhitespace(tr
))
553 ch
= tr
->mRing
[tr
->mOut
&TR_RING_MASK
];
554 if(ch
== '_' || isalpha(ch
))
564 ch
= tr
->mRing
[tr
->mOut
&TR_RING_MASK
];
565 } while(ch
== '_' || isdigit(ch
) || isalpha(ch
));
573 TrErrorAt(tr
, tr
->mLine
, col
, "Identifier is too long.\n");
577 TrErrorAt(tr
, tr
->mLine
, col
, "Expected an identifier.\n");
581 // Reads and validates (including bounds) an integer token.
582 static int TrReadInt(TokenReaderT
*tr
, const int loBound
, const int hiBound
, int *value
)
584 uint col
, digis
, len
;
588 if(TrSkipWhitespace(tr
))
592 ch
= tr
->mRing
[tr
->mOut
&TR_RING_MASK
];
593 if(ch
== '+' || ch
== '-')
602 ch
= tr
->mRing
[tr
->mOut
&TR_RING_MASK
];
603 if(!isdigit(ch
)) break;
611 if(digis
> 0 && ch
!= '.' && !isalpha(ch
))
615 TrErrorAt(tr
, tr
->mLine
, col
, "Integer is too long.");
619 *value
= strtol(temp
, NULL
, 10);
620 if(*value
< loBound
|| *value
> hiBound
)
622 TrErrorAt(tr
, tr
->mLine
, col
, "Expected a value from %d to %d.\n", loBound
, hiBound
);
628 TrErrorAt(tr
, tr
->mLine
, col
, "Expected an integer.\n");
632 // Reads and validates (including bounds) a float token.
633 static int TrReadFloat(TokenReaderT
*tr
, const double loBound
, const double hiBound
, double *value
)
635 uint col
, digis
, len
;
639 if(TrSkipWhitespace(tr
))
643 ch
= tr
->mRing
[tr
->mOut
&TR_RING_MASK
];
644 if(ch
== '+' || ch
== '-')
654 ch
= tr
->mRing
[tr
->mOut
&TR_RING_MASK
];
655 if(!isdigit(ch
)) break;
671 ch
= tr
->mRing
[tr
->mOut
&TR_RING_MASK
];
672 if(!isdigit(ch
)) break;
681 if(ch
== 'E' || ch
== 'e')
688 if(ch
== '+' || ch
== '-')
697 ch
= tr
->mRing
[tr
->mOut
&TR_RING_MASK
];
698 if(!isdigit(ch
)) break;
707 if(digis
> 0 && ch
!= '.' && !isalpha(ch
))
711 TrErrorAt(tr
, tr
->mLine
, col
, "Float is too long.");
715 *value
= strtod(temp
, NULL
);
716 if(*value
< loBound
|| *value
> hiBound
)
718 TrErrorAt (tr
, tr
->mLine
, col
, "Expected a value from %f to %f.\n", loBound
, hiBound
);
727 TrErrorAt(tr
, tr
->mLine
, col
, "Expected a float.\n");
731 // Reads and validates a string token.
732 static int TrReadString(TokenReaderT
*tr
, const uint maxLen
, char *text
)
738 if(TrSkipWhitespace(tr
))
741 ch
= tr
->mRing
[tr
->mOut
&TR_RING_MASK
];
748 ch
= tr
->mRing
[tr
->mOut
&TR_RING_MASK
];
754 TrErrorAt (tr
, tr
->mLine
, col
, "Unterminated string at end of line.\n");
763 tr
->mColumn
+= 1 + len
;
764 TrErrorAt(tr
, tr
->mLine
, col
, "Unterminated string at end of input.\n");
767 tr
->mColumn
+= 2 + len
;
770 TrErrorAt (tr
, tr
->mLine
, col
, "String is too long.\n");
777 TrErrorAt(tr
, tr
->mLine
, col
, "Expected a string.\n");
781 // Reads and validates the given operator.
782 static int TrReadOperator(TokenReaderT
*tr
, const char *op
)
788 if(TrSkipWhitespace(tr
))
792 while(op
[len
] != '\0' && TrLoad(tr
))
794 ch
= tr
->mRing
[tr
->mOut
&TR_RING_MASK
];
795 if(ch
!= op
[len
]) break;
803 TrErrorAt(tr
, tr
->mLine
, col
, "Expected '%s' operator.\n", op
);
807 /* Performs a string substitution. Any case-insensitive occurrences of the
808 * pattern string are replaced with the replacement string. The result is
809 * truncated if necessary.
811 static int StrSubst(const char *in
, const char *pat
, const char *rep
, const size_t maxLen
, char *out
)
813 size_t inLen
, patLen
, repLen
;
818 patLen
= strlen(pat
);
819 repLen
= strlen(rep
);
823 while(si
< inLen
&& di
< maxLen
)
825 if(patLen
<= inLen
-si
)
827 if(strncasecmp(&in
[si
], pat
, patLen
) == 0)
829 if(repLen
> maxLen
-di
)
831 repLen
= maxLen
- di
;
834 strncpy(&out
[di
], rep
, repLen
);
850 /*********************
851 *** Math routines ***
852 *********************/
854 // Provide missing math routines for MSVC versions < 1800 (Visual Studio 2013).
855 #if defined(_MSC_VER) && _MSC_VER < 1800
856 static double round(double val
)
859 return ceil(val
-0.5);
860 return floor(val
+0.5);
863 static double fmin(double a
, double b
)
865 return (a
<b
) ? a
: b
;
868 static double fmax(double a
, double b
)
870 return (a
>b
) ? a
: b
;
874 // Simple clamp routine.
875 static double Clamp(const double val
, const double lower
, const double upper
)
877 return fmin(fmax(val
, lower
), upper
);
880 // Performs linear interpolation.
881 static double Lerp(const double a
, const double b
, const double f
)
883 return a
+ (f
* (b
- a
));
886 static inline uint
dither_rng(uint
*seed
)
888 *seed
= (*seed
* 96314165) + 907633515;
892 // Performs a triangular probability density function dither. It assumes the
893 // input sample is already scaled.
894 static inline double TpdfDither(const double in
, uint
*seed
)
896 static const double PRNG_SCALE
= 1.0 / UINT_MAX
;
899 prn0
= dither_rng(seed
);
900 prn1
= dither_rng(seed
);
901 return round(in
+ (prn0
*PRNG_SCALE
- prn1
*PRNG_SCALE
));
904 // Allocates an array of doubles.
905 static double *CreateArray(size_t n
)
910 a
= calloc(n
, sizeof(double));
913 fprintf(stderr
, "Error: Out of memory.\n");
919 // Frees an array of doubles.
920 static void DestroyArray(double *a
)
923 /* Fast Fourier transform routines. The number of points must be a power of
924 * two. In-place operation is possible only if both the real and imaginary
925 * parts are in-place together.
928 // Performs bit-reversal ordering.
929 static void FftArrange(const uint n
, const Complex
*in
, Complex
*out
)
935 // Handle in-place arrangement.
941 Complex temp
= in
[rk
];
953 // Handle copy arrangement.
966 // Performs the summation.
967 static void FftSummation(const int n
, const double s
, Complex
*cplx
)
974 for(m
= 1, m2
= 2;m
< n
; m
<<= 1, m2
<<= 1)
976 // v = Complex (-2.0 * sin (0.5 * pi / m) * sin (0.5 * pi / m), -sin (pi / m))
977 double sm
= sin(0.5 * pi
/ m
);
978 Complex v
= MakeComplex(-2.0*sm
*sm
, -sin(pi
/ m
));
979 Complex w
= MakeComplex(1.0, 0.0);
982 for(k
= i
;k
< n
;k
+= m2
)
986 t
= c_mul(w
, cplx
[mk
]);
987 cplx
[mk
] = c_sub(cplx
[k
], t
);
988 cplx
[k
] = c_add(cplx
[k
], t
);
990 w
= c_add(w
, c_mul(v
, w
));
995 // Performs a forward FFT.
996 static void FftForward(const uint n
, const Complex
*in
, Complex
*out
)
998 FftArrange(n
, in
, out
);
999 FftSummation(n
, 1.0, out
);
1002 // Performs an inverse FFT.
1003 static void FftInverse(const uint n
, const Complex
*in
, Complex
*out
)
1008 FftArrange(n
, in
, out
);
1009 FftSummation(n
, -1.0, out
);
1011 for(i
= 0;i
< n
;i
++)
1018 /* Calculate the complex helical sequence (or discrete-time analytical signal)
1019 * of the given input using the Hilbert transform. Given the natural logarithm
1020 * of a signal's magnitude response, the imaginary components can be used as
1021 * the angles for minimum-phase reconstruction.
1023 static void Hilbert(const uint n
, const Complex
*in
, Complex
*out
)
1029 // Handle in-place operation.
1030 for(i
= 0;i
< n
;i
++)
1035 // Handle copy operation.
1036 for(i
= 0;i
< n
;i
++)
1038 out
[i
].Real
= in
[i
].Real
;
1042 FftInverse(n
, out
, out
);
1043 for(i
= 1;i
< (n
+1)/2;i
++)
1048 /* Increment i if n is even. */
1055 FftForward(n
, out
, out
);
1058 /* Calculate the magnitude response of the given input. This is used in
1059 * place of phase decomposition, since the phase residuals are discarded for
1060 * minimum phase reconstruction. The mirrored half of the response is also
1063 static void MagnitudeResponse(const uint n
, const Complex
*in
, double *out
)
1065 const uint m
= 1 + (n
/ 2);
1067 for(i
= 0;i
< m
;i
++)
1068 out
[i
] = fmax(c_abs(in
[i
]), EPSILON
);
1071 /* Apply a range limit (in dB) to the given magnitude response. This is used
1072 * to adjust the effects of the diffuse-field average on the equalization
1075 static void LimitMagnitudeResponse(const uint n
, const double limit
, const double *in
, double *out
)
1077 const uint m
= 1 + (n
/ 2);
1079 uint i
, lower
, upper
;
1082 halfLim
= limit
/ 2.0;
1083 // Convert the response to dB.
1084 for(i
= 0;i
< m
;i
++)
1085 out
[i
] = 20.0 * log10(in
[i
]);
1086 // Use six octaves to calculate the average magnitude of the signal.
1087 lower
= ((uint
)ceil(n
/ pow(2.0, 8.0))) - 1;
1088 upper
= ((uint
)floor(n
/ pow(2.0, 2.0))) - 1;
1090 for(i
= lower
;i
<= upper
;i
++)
1092 ave
/= upper
- lower
+ 1;
1093 // Keep the response within range of the average magnitude.
1094 for(i
= 0;i
< m
;i
++)
1095 out
[i
] = Clamp(out
[i
], ave
- halfLim
, ave
+ halfLim
);
1096 // Convert the response back to linear magnitude.
1097 for(i
= 0;i
< m
;i
++)
1098 out
[i
] = pow(10.0, out
[i
] / 20.0);
1101 /* Reconstructs the minimum-phase component for the given magnitude response
1102 * of a signal. This is equivalent to phase recomposition, sans the missing
1103 * residuals (which were discarded). The mirrored half of the response is
1106 static void MinimumPhase(const uint n
, const double *in
, Complex
*out
)
1108 const uint m
= 1 + (n
/ 2);
1112 mags
= CreateArray(n
);
1113 for(i
= 0;i
< m
;i
++)
1115 mags
[i
] = fmax(EPSILON
, in
[i
]);
1116 out
[i
].Real
= log(mags
[i
]);
1121 mags
[i
] = mags
[n
- i
];
1122 out
[i
] = out
[n
- i
];
1124 Hilbert(n
, out
, out
);
1125 // Remove any DC offset the filter has.
1127 for(i
= 0;i
< n
;i
++)
1129 Complex a
= c_exp(MakeComplex(0.0, out
[i
].Imag
));
1130 out
[i
] = c_mul(MakeComplex(mags
[i
], 0.0), a
);
1136 /***************************
1137 *** Resampler functions ***
1138 ***************************/
1140 /* This is the normalized cardinal sine (sinc) function.
1142 * sinc(x) = { 1, x = 0
1143 * { sin(pi x) / (pi x), otherwise.
1145 static double Sinc(const double x
)
1147 if(fabs(x
) < EPSILON
)
1149 return sin(M_PI
* x
) / (M_PI
* x
);
1152 /* The zero-order modified Bessel function of the first kind, used for the
1155 * I_0(x) = sum_{k=0}^inf (1 / k!)^2 (x / 2)^(2 k)
1156 * = sum_{k=0}^inf ((x / 2)^k / k!)^2
1158 static double BesselI_0(const double x
)
1160 double term
, sum
, x2
, y
, last_sum
;
1163 // Start at k=1 since k=0 is trivial.
1169 // Let the integration converge until the term of the sum is no longer
1177 } while(sum
!= last_sum
);
1181 /* Calculate a Kaiser window from the given beta value and a normalized k
1184 * w(k) = { I_0(B sqrt(1 - k^2)) / I_0(B), -1 <= k <= 1
1187 * Where k can be calculated as:
1189 * k = i / l, where -l <= i <= l.
1193 * k = 2 i / M - 1, where 0 <= i <= M.
1195 static double Kaiser(const double b
, const double k
)
1197 if(!(k
>= -1.0 && k
<= 1.0))
1199 return BesselI_0(b
* sqrt(1.0 - k
*k
)) / BesselI_0(b
);
1202 // Calculates the greatest common divisor of a and b.
1203 static uint
Gcd(uint x
, uint y
)
1214 /* Calculates the size (order) of the Kaiser window. Rejection is in dB and
1215 * the transition width is normalized frequency (0.5 is nyquist).
1217 * M = { ceil((r - 7.95) / (2.285 2 pi f_t)), r > 21
1218 * { ceil(5.79 / 2 pi f_t), r <= 21.
1221 static uint
CalcKaiserOrder(const double rejection
, const double transition
)
1223 double w_t
= 2.0 * M_PI
* transition
;
1224 if(rejection
> 21.0)
1225 return (uint
)ceil((rejection
- 7.95) / (2.285 * w_t
));
1226 return (uint
)ceil(5.79 / w_t
);
1229 // Calculates the beta value of the Kaiser window. Rejection is in dB.
1230 static double CalcKaiserBeta(const double rejection
)
1232 if(rejection
> 50.0)
1233 return 0.1102 * (rejection
- 8.7);
1234 if(rejection
>= 21.0)
1235 return (0.5842 * pow(rejection
- 21.0, 0.4)) +
1236 (0.07886 * (rejection
- 21.0));
1240 /* Calculates a point on the Kaiser-windowed sinc filter for the given half-
1241 * width, beta, gain, and cutoff. The point is specified in non-normalized
1242 * samples, from 0 to M, where M = (2 l + 1).
1244 * w(k) 2 p f_t sinc(2 f_t x)
1246 * x -- centered sample index (i - l)
1247 * k -- normalized and centered window index (x / l)
1248 * w(k) -- window function (Kaiser)
1249 * p -- gain compensation factor when sampling
1250 * f_t -- normalized center frequency (or cutoff; 0.5 is nyquist)
1252 static double SincFilter(const int l
, const double b
, const double gain
, const double cutoff
, const int i
)
1254 return Kaiser(b
, (double)(i
- l
) / l
) * 2.0 * gain
* cutoff
* Sinc(2.0 * cutoff
* (i
- l
));
1257 /* This is a polyphase sinc-filtered resampler.
1259 * Upsample Downsample
1261 * p/q = 3/2 p/q = 3/5
1263 * M-+-+-+-> M-+-+-+->
1264 * -------------------+ ---------------------+
1265 * p s * f f f f|f| | p s * f f f f f |
1266 * | 0 * 0 0 0|0|0 | | 0 * 0 0 0 0|0| |
1267 * v 0 * 0 0|0|0 0 | v 0 * 0 0 0|0|0 |
1268 * s * f|f|f f f | s * f f|f|f f |
1269 * 0 * |0|0 0 0 0 | 0 * 0|0|0 0 0 |
1270 * --------+=+--------+ 0 * |0|0 0 0 0 |
1271 * d . d .|d|. d . d ----------+=+--------+
1272 * d . . . .|d|. . . .
1276 * P_f(i,j) = q i mod p + pj
1277 * P_s(i,j) = floor(q i / p) - j
1278 * d[i=0..N-1] = sum_{j=0}^{floor((M - 1) / p)} {
1279 * { f[P_f(i,j)] s[P_s(i,j)], P_f(i,j) < M
1280 * { 0, P_f(i,j) >= M. }
1283 // Calculate the resampling metrics and build the Kaiser-windowed sinc filter
1284 // that's used to cut frequencies above the destination nyquist.
1285 static void ResamplerSetup(ResamplerT
*rs
, const uint srcRate
, const uint dstRate
)
1287 double cutoff
, width
, beta
;
1291 gcd
= Gcd(srcRate
, dstRate
);
1292 rs
->mP
= dstRate
/ gcd
;
1293 rs
->mQ
= srcRate
/ gcd
;
1294 /* The cutoff is adjusted by half the transition width, so the transition
1295 * ends before the nyquist (0.5). Both are scaled by the downsampling
1300 cutoff
= 0.475 / rs
->mP
;
1301 width
= 0.05 / rs
->mP
;
1305 cutoff
= 0.475 / rs
->mQ
;
1306 width
= 0.05 / rs
->mQ
;
1308 // A rejection of -180 dB is used for the stop band. Round up when
1309 // calculating the left offset to avoid increasing the transition width.
1310 l
= (CalcKaiserOrder(180.0, width
)+1) / 2;
1311 beta
= CalcKaiserBeta(180.0);
1314 rs
->mF
= CreateArray(rs
->mM
);
1315 for(i
= 0;i
< ((int)rs
->mM
);i
++)
1316 rs
->mF
[i
] = SincFilter((int)l
, beta
, rs
->mP
, cutoff
, i
);
1319 // Clean up after the resampler.
1320 static void ResamplerClear(ResamplerT
*rs
)
1322 DestroyArray(rs
->mF
);
1326 // Perform the upsample-filter-downsample resampling operation using a
1327 // polyphase filter implementation.
1328 static void ResamplerRun(ResamplerT
*rs
, const uint inN
, const double *in
, const uint outN
, double *out
)
1330 const uint p
= rs
->mP
, q
= rs
->mQ
, m
= rs
->mM
, l
= rs
->mL
;
1331 const double *f
= rs
->mF
;
1339 // Handle in-place operation.
1341 work
= CreateArray(outN
);
1344 // Resample the input.
1345 for(i
= 0;i
< outN
;i
++)
1348 // Input starts at l to compensate for the filter delay. This will
1349 // drop any build-up from the first half of the filter.
1350 j_f
= (l
+ (q
* i
)) % p
;
1351 j_s
= (l
+ (q
* i
)) / p
;
1354 // Only take input when 0 <= j_s < inN. This single unsigned
1355 // comparison catches both cases.
1357 r
+= f
[j_f
] * in
[j_s
];
1363 // Clean up after in-place operation.
1366 for(i
= 0;i
< outN
;i
++)
1372 /*************************
1373 *** File source input ***
1374 *************************/
1376 // Read a binary value of the specified byte order and byte size from a file,
1377 // storing it as a 32-bit unsigned integer.
1378 static int ReadBin4(FILE *fp
, const char *filename
, const ByteOrderT order
, const uint bytes
, uint32
*out
)
1384 if(fread(in
, 1, bytes
, fp
) != bytes
)
1386 fprintf(stderr
, "Error: Bad read from file '%s'.\n", filename
);
1393 for(i
= 0;i
< bytes
;i
++)
1394 accum
= (accum
<<8) | in
[bytes
- i
- 1];
1397 for(i
= 0;i
< bytes
;i
++)
1398 accum
= (accum
<<8) | in
[i
];
1407 // Read a binary value of the specified byte order from a file, storing it as
1408 // a 64-bit unsigned integer.
1409 static int ReadBin8(FILE *fp
, const char *filename
, const ByteOrderT order
, uint64
*out
)
1415 if(fread(in
, 1, 8, fp
) != 8)
1417 fprintf(stderr
, "Error: Bad read from file '%s'.\n", filename
);
1424 for(i
= 0;i
< 8;i
++)
1425 accum
= (accum
<<8) | in
[8 - i
- 1];
1428 for(i
= 0;i
< 8;i
++)
1429 accum
= (accum
<<8) | in
[i
];
1438 /* Read a binary value of the specified type, byte order, and byte size from
1439 * a file, converting it to a double. For integer types, the significant
1440 * bits are used to normalize the result. The sign of bits determines
1441 * whether they are padded toward the MSB (negative) or LSB (positive).
1442 * Floating-point types are not normalized.
1444 static int ReadBinAsDouble(FILE *fp
, const char *filename
, const ByteOrderT order
, const ElementTypeT type
, const uint bytes
, const int bits
, double *out
)
1459 if(!ReadBin8(fp
, filename
, order
, &v8
.ui
))
1466 if(!ReadBin4(fp
, filename
, order
, bytes
, &v4
.ui
))
1473 v4
.ui
>>= (8*bytes
) - ((uint
)bits
);
1475 v4
.ui
&= (0xFFFFFFFF >> (32+bits
));
1477 if(v4
.ui
&(uint
)(1<<(abs(bits
)-1)))
1478 v4
.ui
|= (0xFFFFFFFF << abs (bits
));
1479 *out
= v4
.i
/ (double)(1<<(abs(bits
)-1));
1485 /* Read an ascii value of the specified type from a file, converting it to a
1486 * double. For integer types, the significant bits are used to normalize the
1487 * result. The sign of the bits should always be positive. This also skips
1488 * up to one separator character before the element itself.
1490 static int ReadAsciiAsDouble(TokenReaderT
*tr
, const char *filename
, const ElementTypeT type
, const uint bits
, double *out
)
1492 if(TrIsOperator(tr
, ","))
1493 TrReadOperator(tr
, ",");
1494 else if(TrIsOperator(tr
, ":"))
1495 TrReadOperator(tr
, ":");
1496 else if(TrIsOperator(tr
, ";"))
1497 TrReadOperator(tr
, ";");
1498 else if(TrIsOperator(tr
, "|"))
1499 TrReadOperator(tr
, "|");
1503 if(!TrReadFloat(tr
, -HUGE_VAL
, HUGE_VAL
, out
))
1505 fprintf(stderr
, "Error: Bad read from file '%s'.\n", filename
);
1512 if(!TrReadInt(tr
, -(1<<(bits
-1)), (1<<(bits
-1))-1, &v
))
1514 fprintf(stderr
, "Error: Bad read from file '%s'.\n", filename
);
1517 *out
= v
/ (double)((1<<(bits
-1))-1);
1522 // Read the RIFF/RIFX WAVE format chunk from a file, validating it against
1523 // the source parameters and data set metrics.
1524 static int ReadWaveFormat(FILE *fp
, const ByteOrderT order
, const uint hrirRate
, SourceRefT
*src
)
1526 uint32 fourCC
, chunkSize
;
1527 uint32 format
, channels
, rate
, dummy
, block
, size
, bits
;
1532 fseek (fp
, (long) chunkSize
, SEEK_CUR
);
1533 if(!ReadBin4(fp
, src
->mPath
, BO_LITTLE
, 4, &fourCC
) ||
1534 !ReadBin4(fp
, src
->mPath
, order
, 4, &chunkSize
))
1536 } while(fourCC
!= FOURCC_FMT
);
1537 if(!ReadBin4(fp
, src
->mPath
, order
, 2, & format
) ||
1538 !ReadBin4(fp
, src
->mPath
, order
, 2, & channels
) ||
1539 !ReadBin4(fp
, src
->mPath
, order
, 4, & rate
) ||
1540 !ReadBin4(fp
, src
->mPath
, order
, 4, & dummy
) ||
1541 !ReadBin4(fp
, src
->mPath
, order
, 2, & block
))
1546 if(!ReadBin4(fp
, src
->mPath
, order
, 2, &size
))
1554 if(format
== WAVE_FORMAT_EXTENSIBLE
)
1556 fseek(fp
, 2, SEEK_CUR
);
1557 if(!ReadBin4(fp
, src
->mPath
, order
, 2, &bits
))
1561 fseek(fp
, 4, SEEK_CUR
);
1562 if(!ReadBin4(fp
, src
->mPath
, order
, 2, &format
))
1564 fseek(fp
, (long)(chunkSize
- 26), SEEK_CUR
);
1570 fseek(fp
, (long)(chunkSize
- 16), SEEK_CUR
);
1572 fseek(fp
, (long)(chunkSize
- 14), SEEK_CUR
);
1574 if(format
!= WAVE_FORMAT_PCM
&& format
!= WAVE_FORMAT_IEEE_FLOAT
)
1576 fprintf(stderr
, "Error: Unsupported WAVE format in file '%s'.\n", src
->mPath
);
1579 if(src
->mChannel
>= channels
)
1581 fprintf(stderr
, "Error: Missing source channel in WAVE file '%s'.\n", src
->mPath
);
1584 if(rate
!= hrirRate
)
1586 fprintf(stderr
, "Error: Mismatched source sample rate in WAVE file '%s'.\n", src
->mPath
);
1589 if(format
== WAVE_FORMAT_PCM
)
1591 if(size
< 2 || size
> 4)
1593 fprintf(stderr
, "Error: Unsupported sample size in WAVE file '%s'.\n", src
->mPath
);
1596 if(bits
< 16 || bits
> (8*size
))
1598 fprintf (stderr
, "Error: Bad significant bits in WAVE file '%s'.\n", src
->mPath
);
1601 src
->mType
= ET_INT
;
1605 if(size
!= 4 && size
!= 8)
1607 fprintf(stderr
, "Error: Unsupported sample size in WAVE file '%s'.\n", src
->mPath
);
1613 src
->mBits
= (int)bits
;
1614 src
->mSkip
= channels
;
1618 // Read a RIFF/RIFX WAVE data chunk, converting all elements to doubles.
1619 static int ReadWaveData(FILE *fp
, const SourceRefT
*src
, const ByteOrderT order
, const uint n
, double *hrir
)
1621 int pre
, post
, skip
;
1624 pre
= (int)(src
->mSize
* src
->mChannel
);
1625 post
= (int)(src
->mSize
* (src
->mSkip
- src
->mChannel
- 1));
1627 for(i
= 0;i
< n
;i
++)
1631 fseek(fp
, skip
, SEEK_CUR
);
1632 if(!ReadBinAsDouble(fp
, src
->mPath
, order
, src
->mType
, src
->mSize
, src
->mBits
, &hrir
[i
]))
1637 fseek(fp
, skip
, SEEK_CUR
);
1641 // Read the RIFF/RIFX WAVE list or data chunk, converting all elements to
1643 static int ReadWaveList(FILE *fp
, const SourceRefT
*src
, const ByteOrderT order
, const uint n
, double *hrir
)
1645 uint32 fourCC
, chunkSize
, listSize
, count
;
1646 uint block
, skip
, offset
, i
;
1650 if(!ReadBin4(fp
, src
->mPath
, BO_LITTLE
, 4, & fourCC
) ||
1651 !ReadBin4(fp
, src
->mPath
, order
, 4, & chunkSize
))
1654 if(fourCC
== FOURCC_DATA
)
1656 block
= src
->mSize
* src
->mSkip
;
1657 count
= chunkSize
/ block
;
1658 if(count
< (src
->mOffset
+ n
))
1660 fprintf(stderr
, "Error: Bad read from file '%s'.\n", src
->mPath
);
1663 fseek(fp
, (long)(src
->mOffset
* block
), SEEK_CUR
);
1664 if(!ReadWaveData(fp
, src
, order
, n
, &hrir
[0]))
1668 else if(fourCC
== FOURCC_LIST
)
1670 if(!ReadBin4(fp
, src
->mPath
, BO_LITTLE
, 4, &fourCC
))
1673 if(fourCC
== FOURCC_WAVL
)
1677 fseek(fp
, (long)chunkSize
, SEEK_CUR
);
1679 listSize
= chunkSize
;
1680 block
= src
->mSize
* src
->mSkip
;
1681 skip
= src
->mOffset
;
1684 while(offset
< n
&& listSize
> 8)
1686 if(!ReadBin4(fp
, src
->mPath
, BO_LITTLE
, 4, &fourCC
) ||
1687 !ReadBin4(fp
, src
->mPath
, order
, 4, &chunkSize
))
1689 listSize
-= 8 + chunkSize
;
1690 if(fourCC
== FOURCC_DATA
)
1692 count
= chunkSize
/ block
;
1695 fseek(fp
, (long)(skip
* block
), SEEK_CUR
);
1696 chunkSize
-= skip
* block
;
1699 if(count
> (n
- offset
))
1701 if(!ReadWaveData(fp
, src
, order
, count
, &hrir
[offset
]))
1703 chunkSize
-= count
* block
;
1705 lastSample
= hrir
[offset
- 1];
1713 else if(fourCC
== FOURCC_SLNT
)
1715 if(!ReadBin4(fp
, src
->mPath
, order
, 4, &count
))
1722 if(count
> (n
- offset
))
1724 for(i
= 0; i
< count
; i
++)
1725 hrir
[offset
+ i
] = lastSample
;
1735 fseek(fp
, (long)chunkSize
, SEEK_CUR
);
1739 fprintf(stderr
, "Error: Bad read from file '%s'.\n", src
->mPath
);
1745 // Load a source HRIR from a RIFF/RIFX WAVE file.
1746 static int LoadWaveSource(FILE *fp
, SourceRefT
*src
, const uint hrirRate
, const uint n
, double *hrir
)
1748 uint32 fourCC
, dummy
;
1751 if(!ReadBin4(fp
, src
->mPath
, BO_LITTLE
, 4, &fourCC
) ||
1752 !ReadBin4(fp
, src
->mPath
, BO_LITTLE
, 4, &dummy
))
1754 if(fourCC
== FOURCC_RIFF
)
1756 else if(fourCC
== FOURCC_RIFX
)
1760 fprintf(stderr
, "Error: No RIFF/RIFX chunk in file '%s'.\n", src
->mPath
);
1764 if(!ReadBin4(fp
, src
->mPath
, BO_LITTLE
, 4, &fourCC
))
1766 if(fourCC
!= FOURCC_WAVE
)
1768 fprintf(stderr
, "Error: Not a RIFF/RIFX WAVE file '%s'.\n", src
->mPath
);
1771 if(!ReadWaveFormat(fp
, order
, hrirRate
, src
))
1773 if(!ReadWaveList(fp
, src
, order
, n
, hrir
))
1778 // Load a source HRIR from a binary file.
1779 static int LoadBinarySource(FILE *fp
, const SourceRefT
*src
, const ByteOrderT order
, const uint n
, double *hrir
)
1783 fseek(fp
, (long)src
->mOffset
, SEEK_SET
);
1784 for(i
= 0;i
< n
;i
++)
1786 if(!ReadBinAsDouble(fp
, src
->mPath
, order
, src
->mType
, src
->mSize
, src
->mBits
, &hrir
[i
]))
1789 fseek(fp
, (long)src
->mSkip
, SEEK_CUR
);
1794 // Load a source HRIR from an ASCII text file containing a list of elements
1795 // separated by whitespace or common list operators (',', ';', ':', '|').
1796 static int LoadAsciiSource(FILE *fp
, const SourceRefT
*src
, const uint n
, double *hrir
)
1802 TrSetup(fp
, NULL
, &tr
);
1803 for(i
= 0;i
< src
->mOffset
;i
++)
1805 if(!ReadAsciiAsDouble(&tr
, src
->mPath
, src
->mType
, (uint
)src
->mBits
, &dummy
))
1808 for(i
= 0;i
< n
;i
++)
1810 if(!ReadAsciiAsDouble(&tr
, src
->mPath
, src
->mType
, (uint
)src
->mBits
, &hrir
[i
]))
1812 for(j
= 0;j
< src
->mSkip
;j
++)
1814 if(!ReadAsciiAsDouble(&tr
, src
->mPath
, src
->mType
, (uint
)src
->mBits
, &dummy
))
1821 // Load a source HRIR from a supported file type.
1822 static int LoadSource(SourceRefT
*src
, const uint hrirRate
, const uint n
, double *hrir
)
1827 if (src
->mFormat
== SF_ASCII
)
1828 fp
= fopen(src
->mPath
, "r");
1830 fp
= fopen(src
->mPath
, "rb");
1833 fprintf(stderr
, "Error: Could not open source file '%s'.\n", src
->mPath
);
1836 if(src
->mFormat
== SF_WAVE
)
1837 result
= LoadWaveSource(fp
, src
, hrirRate
, n
, hrir
);
1838 else if(src
->mFormat
== SF_BIN_LE
)
1839 result
= LoadBinarySource(fp
, src
, BO_LITTLE
, n
, hrir
);
1840 else if(src
->mFormat
== SF_BIN_BE
)
1841 result
= LoadBinarySource(fp
, src
, BO_BIG
, n
, hrir
);
1843 result
= LoadAsciiSource(fp
, src
, n
, hrir
);
1849 /***************************
1850 *** File storage output ***
1851 ***************************/
1853 // Write an ASCII string to a file.
1854 static int WriteAscii(const char *out
, FILE *fp
, const char *filename
)
1859 if(fwrite(out
, 1, len
, fp
) != len
)
1862 fprintf(stderr
, "Error: Bad write to file '%s'.\n", filename
);
1868 // Write a binary value of the given byte order and byte size to a file,
1869 // loading it from a 32-bit unsigned integer.
1870 static int WriteBin4(const ByteOrderT order
, const uint bytes
, const uint32 in
, FILE *fp
, const char *filename
)
1878 for(i
= 0;i
< bytes
;i
++)
1879 out
[i
] = (in
>>(i
*8)) & 0x000000FF;
1882 for(i
= 0;i
< bytes
;i
++)
1883 out
[bytes
- i
- 1] = (in
>>(i
*8)) & 0x000000FF;
1888 if(fwrite(out
, 1, bytes
, fp
) != bytes
)
1890 fprintf(stderr
, "Error: Bad write to file '%s'.\n", filename
);
1896 // Store the OpenAL Soft HRTF data set.
1897 static int StoreMhr(const HrirDataT
*hData
, const int experimental
, const char *filename
)
1899 uint e
, step
, end
, n
, j
, i
;
1904 if((fp
=fopen(filename
, "wb")) == NULL
)
1906 fprintf(stderr
, "Error: Could not open MHR file '%s'.\n", filename
);
1909 if(!WriteAscii(experimental
? MHR_FORMAT_EXPERIMENTAL
: MHR_FORMAT
, fp
, filename
))
1911 if(!WriteBin4(BO_LITTLE
, 4, (uint32
)hData
->mIrRate
, fp
, filename
))
1915 if(!WriteBin4(BO_LITTLE
, 1, (uint32
)hData
->mSampleType
, fp
, filename
))
1917 if(!WriteBin4(BO_LITTLE
, 1, (uint32
)hData
->mChannelType
, fp
, filename
))
1920 if(!WriteBin4(BO_LITTLE
, 1, (uint32
)hData
->mIrPoints
, fp
, filename
))
1922 if(!WriteBin4(BO_LITTLE
, 1, (uint32
)hData
->mEvCount
, fp
, filename
))
1924 for(e
= 0;e
< hData
->mEvCount
;e
++)
1926 if(!WriteBin4(BO_LITTLE
, 1, (uint32
)hData
->mAzCount
[e
], fp
, filename
))
1929 step
= hData
->mIrSize
;
1930 end
= hData
->mIrCount
* step
;
1931 n
= hData
->mIrPoints
;
1932 dither_seed
= 22222;
1933 for(j
= 0;j
< end
;j
+= step
)
1935 const double scale
= (!experimental
|| hData
->mSampleType
== ST_S16
) ? 32767.0 :
1936 ((hData
->mSampleType
== ST_S24
) ? 8388607.0 : 0.0);
1937 const int bps
= (!experimental
|| hData
->mSampleType
== ST_S16
) ? 2 :
1938 ((hData
->mSampleType
== ST_S24
) ? 3 : 0);
1939 double out
[MAX_TRUNCSIZE
];
1940 for(i
= 0;i
< n
;i
++)
1941 out
[i
] = TpdfDither(scale
* hData
->mHrirs
[j
+i
], &dither_seed
);
1942 for(i
= 0;i
< n
;i
++)
1944 v
= (int)Clamp(out
[i
], -scale
-1.0, scale
);
1945 if(!WriteBin4(BO_LITTLE
, bps
, (uint32
)v
, fp
, filename
))
1949 for(j
= 0;j
< hData
->mIrCount
;j
++)
1951 v
= (int)fmin(round(hData
->mIrRate
* hData
->mHrtds
[j
]), MAX_HRTD
);
1952 if(!WriteBin4(BO_LITTLE
, 1, (uint32
)v
, fp
, filename
))
1960 /***********************
1961 *** HRTF processing ***
1962 ***********************/
1964 // Calculate the onset time of an HRIR and average it with any existing
1965 // timing for its elevation and azimuth.
1966 static void AverageHrirOnset(const double *hrir
, const double f
, const uint ei
, const uint ai
, const HrirDataT
*hData
)
1972 n
= hData
->mIrPoints
;
1973 for(i
= 0;i
< n
;i
++)
1974 mag
= fmax(fabs(hrir
[i
]), mag
);
1976 for(i
= 0;i
< n
;i
++)
1978 if(fabs(hrir
[i
]) >= mag
)
1981 j
= hData
->mEvOffset
[ei
] + ai
;
1982 hData
->mHrtds
[j
] = Lerp(hData
->mHrtds
[j
], ((double)i
) / hData
->mIrRate
, f
);
1985 // Calculate the magnitude response of an HRIR and average it with any
1986 // existing responses for its elevation and azimuth.
1987 static void AverageHrirMagnitude(const double *hrir
, const double f
, const uint ei
, const uint ai
, const HrirDataT
*hData
)
1993 n
= hData
->mFftSize
;
1994 cplx
= calloc(sizeof(*cplx
), n
);
1995 mags
= calloc(sizeof(*mags
), n
);
1996 for(i
= 0;i
< hData
->mIrPoints
;i
++)
1997 cplx
[i
] = MakeComplex(hrir
[i
], 0.0);
1999 cplx
[i
] = MakeComplex(0.0, 0.0);
2000 FftForward(n
, cplx
, cplx
);
2001 MagnitudeResponse(n
, cplx
, mags
);
2003 j
= (hData
->mEvOffset
[ei
] + ai
) * hData
->mIrSize
;
2004 for(i
= 0;i
< m
;i
++)
2005 hData
->mHrirs
[j
+i
] = Lerp(hData
->mHrirs
[j
+i
], mags
[i
], f
);
2010 /* Calculate the contribution of each HRIR to the diffuse-field average based
2011 * on the area of its surface patch. All patches are centered at the HRIR
2012 * coordinates on the unit sphere and are measured by solid angle.
2014 static void CalculateDfWeights(const HrirDataT
*hData
, double *weights
)
2016 double evs
, sum
, ev
, up_ev
, down_ev
, solidAngle
;
2019 evs
= 90.0 / (hData
->mEvCount
- 1);
2021 for(ei
= hData
->mEvStart
;ei
< hData
->mEvCount
;ei
++)
2023 // For each elevation, calculate the upper and lower limits of the
2025 ev
= -90.0 + (ei
* 2.0 * evs
);
2026 if(ei
< (hData
->mEvCount
- 1))
2027 up_ev
= (ev
+ evs
) * M_PI
/ 180.0;
2031 down_ev
= (ev
- evs
) * M_PI
/ 180.0;
2033 down_ev
= -M_PI
/ 2.0;
2034 // Calculate the area of the patch band.
2035 solidAngle
= 2.0 * M_PI
* (sin(up_ev
) - sin(down_ev
));
2036 // Each weight is the area of one patch.
2037 weights
[ei
] = solidAngle
/ hData
->mAzCount
[ei
];
2038 // Sum the total surface area covered by the HRIRs.
2041 // Normalize the weights given the total surface coverage.
2042 for(ei
= hData
->mEvStart
;ei
< hData
->mEvCount
;ei
++)
2046 /* Calculate the diffuse-field average from the given magnitude responses of
2047 * the HRIR set. Weighting can be applied to compensate for the varying
2048 * surface area covered by each HRIR. The final average can then be limited
2049 * by the specified magnitude range (in positive dB; 0.0 to skip).
2051 static void CalculateDiffuseFieldAverage(const HrirDataT
*hData
, const int weighted
, const double limit
, double *dfa
)
2053 uint ei
, ai
, count
, step
, start
, end
, m
, j
, i
;
2056 weights
= CreateArray(hData
->mEvCount
);
2059 // Use coverage weighting to calculate the average.
2060 CalculateDfWeights(hData
, weights
);
2064 // If coverage weighting is not used, the weights still need to be
2065 // averaged by the number of HRIRs.
2067 for(ei
= hData
->mEvStart
;ei
< hData
->mEvCount
;ei
++)
2068 count
+= hData
->mAzCount
[ei
];
2069 for(ei
= hData
->mEvStart
;ei
< hData
->mEvCount
;ei
++)
2070 weights
[ei
] = 1.0 / count
;
2072 ei
= hData
->mEvStart
;
2074 step
= hData
->mIrSize
;
2075 start
= hData
->mEvOffset
[ei
] * step
;
2076 end
= hData
->mIrCount
* step
;
2077 m
= 1 + (hData
->mFftSize
/ 2);
2078 for(i
= 0;i
< m
;i
++)
2080 for(j
= start
;j
< end
;j
+= step
)
2082 // Get the weight for this HRIR's contribution.
2083 double weight
= weights
[ei
];
2084 // Add this HRIR's weighted power average to the total.
2085 for(i
= 0;i
< m
;i
++)
2086 dfa
[i
] += weight
* hData
->mHrirs
[j
+i
] * hData
->mHrirs
[j
+i
];
2087 // Determine the next weight to use.
2089 if(ai
>= hData
->mAzCount
[ei
])
2095 // Finish the average calculation and keep it from being too small.
2096 for(i
= 0;i
< m
;i
++)
2097 dfa
[i
] = fmax(sqrt(dfa
[i
]), EPSILON
);
2098 // Apply a limit to the magnitude range of the diffuse-field average if
2101 LimitMagnitudeResponse(hData
->mFftSize
, limit
, dfa
, dfa
);
2102 DestroyArray(weights
);
2105 // Perform diffuse-field equalization on the magnitude responses of the HRIR
2106 // set using the given average response.
2107 static void DiffuseFieldEqualize(const double *dfa
, const HrirDataT
*hData
)
2109 uint step
, start
, end
, m
, j
, i
;
2111 step
= hData
->mIrSize
;
2112 start
= hData
->mEvOffset
[hData
->mEvStart
] * step
;
2113 end
= hData
->mIrCount
* step
;
2114 m
= 1 + (hData
->mFftSize
/ 2);
2115 for(j
= start
;j
< end
;j
+= step
)
2117 for(i
= 0;i
< m
;i
++)
2118 hData
->mHrirs
[j
+i
] /= dfa
[i
];
2122 // Perform minimum-phase reconstruction using the magnitude responses of the
2124 static void ReconstructHrirs(const HrirDataT
*hData
)
2126 uint step
, start
, end
, n
, j
, i
;
2129 step
= hData
->mIrSize
;
2130 start
= hData
->mEvOffset
[hData
->mEvStart
] * step
;
2131 end
= hData
->mIrCount
* step
;
2132 n
= hData
->mFftSize
;
2133 cplx
= calloc(sizeof(*cplx
), n
);
2134 for(j
= start
;j
< end
;j
+= step
)
2136 MinimumPhase(n
, &hData
->mHrirs
[j
], cplx
);
2137 FftInverse(n
, cplx
, cplx
);
2138 for(i
= 0;i
< hData
->mIrPoints
;i
++)
2139 hData
->mHrirs
[j
+i
] = cplx
[i
].Real
;
2144 // Resamples the HRIRs for use at the given sampling rate.
2145 static void ResampleHrirs(const uint rate
, HrirDataT
*hData
)
2147 uint n
, step
, start
, end
, j
;
2150 ResamplerSetup(&rs
, hData
->mIrRate
, rate
);
2151 n
= hData
->mIrPoints
;
2152 step
= hData
->mIrSize
;
2153 start
= hData
->mEvOffset
[hData
->mEvStart
] * step
;
2154 end
= hData
->mIrCount
* step
;
2155 for(j
= start
;j
< end
;j
+= step
)
2156 ResamplerRun(&rs
, n
, &hData
->mHrirs
[j
], n
, &hData
->mHrirs
[j
]);
2157 ResamplerClear(&rs
);
2158 hData
->mIrRate
= rate
;
2161 /* Given an elevation index and an azimuth, calculate the indices of the two
2162 * HRIRs that bound the coordinate along with a factor for calculating the
2163 * continous HRIR using interpolation.
2165 static void CalcAzIndices(const HrirDataT
*hData
, const uint ei
, const double az
, uint
*j0
, uint
*j1
, double *jf
)
2170 af
= ((2.0*M_PI
) + az
) * hData
->mAzCount
[ei
] / (2.0*M_PI
);
2171 ai
= ((uint
)af
) % hData
->mAzCount
[ei
];
2174 *j0
= hData
->mEvOffset
[ei
] + ai
;
2175 *j1
= hData
->mEvOffset
[ei
] + ((ai
+1) % hData
->mAzCount
[ei
]);
2179 // Synthesize any missing onset timings at the bottom elevations. This just
2180 // blends between slightly exaggerated known onsets. Not an accurate model.
2181 static void SynthesizeOnsets(HrirDataT
*hData
)
2183 uint oi
, e
, a
, j0
, j1
;
2186 oi
= hData
->mEvStart
;
2188 for(a
= 0;a
< hData
->mAzCount
[oi
];a
++)
2189 t
+= hData
->mHrtds
[hData
->mEvOffset
[oi
] + a
];
2190 hData
->mHrtds
[0] = 1.32e-4 + (t
/ hData
->mAzCount
[oi
]);
2191 for(e
= 1;e
< hData
->mEvStart
;e
++)
2193 of
= ((double)e
) / hData
->mEvStart
;
2194 for(a
= 0;a
< hData
->mAzCount
[e
];a
++)
2196 CalcAzIndices(hData
, oi
, a
* 2.0 * M_PI
/ hData
->mAzCount
[e
], &j0
, &j1
, &jf
);
2197 hData
->mHrtds
[hData
->mEvOffset
[e
] + a
] = Lerp(hData
->mHrtds
[0], Lerp(hData
->mHrtds
[j0
], hData
->mHrtds
[j1
], jf
), of
);
2202 /* Attempt to synthesize any missing HRIRs at the bottom elevations. Right
2203 * now this just blends the lowest elevation HRIRs together and applies some
2204 * attenuation and high frequency damping. It is a simple, if inaccurate
2207 static void SynthesizeHrirs (HrirDataT
*hData
)
2209 uint oi
, a
, e
, step
, n
, i
, j
;
2210 double lp
[4], s0
, s1
;
2215 if(hData
->mEvStart
<= 0)
2217 step
= hData
->mIrSize
;
2218 oi
= hData
->mEvStart
;
2219 n
= hData
->mIrPoints
;
2220 for(i
= 0;i
< n
;i
++)
2221 hData
->mHrirs
[i
] = 0.0;
2222 for(a
= 0;a
< hData
->mAzCount
[oi
];a
++)
2224 j
= (hData
->mEvOffset
[oi
] + a
) * step
;
2225 for(i
= 0;i
< n
;i
++)
2226 hData
->mHrirs
[i
] += hData
->mHrirs
[j
+i
] / hData
->mAzCount
[oi
];
2228 for(e
= 1;e
< hData
->mEvStart
;e
++)
2230 of
= ((double)e
) / hData
->mEvStart
;
2231 b
= (1.0 - of
) * (3.5e-6 * hData
->mIrRate
);
2232 for(a
= 0;a
< hData
->mAzCount
[e
];a
++)
2234 j
= (hData
->mEvOffset
[e
] + a
) * step
;
2235 CalcAzIndices(hData
, oi
, a
* 2.0 * M_PI
/ hData
->mAzCount
[e
], &j0
, &j1
, &jf
);
2242 for(i
= 0;i
< n
;i
++)
2244 s0
= hData
->mHrirs
[i
];
2245 s1
= Lerp(hData
->mHrirs
[j0
+i
], hData
->mHrirs
[j1
+i
], jf
);
2246 s0
= Lerp(s0
, s1
, of
);
2247 lp
[0] = Lerp(s0
, lp
[0], b
);
2248 lp
[1] = Lerp(lp
[0], lp
[1], b
);
2249 lp
[2] = Lerp(lp
[1], lp
[2], b
);
2250 lp
[3] = Lerp(lp
[2], lp
[3], b
);
2251 hData
->mHrirs
[j
+i
] = lp
[3];
2255 b
= 3.5e-6 * hData
->mIrRate
;
2260 for(i
= 0;i
< n
;i
++)
2262 s0
= hData
->mHrirs
[i
];
2263 lp
[0] = Lerp(s0
, lp
[0], b
);
2264 lp
[1] = Lerp(lp
[0], lp
[1], b
);
2265 lp
[2] = Lerp(lp
[1], lp
[2], b
);
2266 lp
[3] = Lerp(lp
[2], lp
[3], b
);
2267 hData
->mHrirs
[i
] = lp
[3];
2269 hData
->mEvStart
= 0;
2272 // The following routines assume a full set of HRIRs for all elevations.
2274 // Normalize the HRIR set and slightly attenuate the result.
2275 static void NormalizeHrirs (const HrirDataT
*hData
)
2277 uint step
, end
, n
, j
, i
;
2280 step
= hData
->mIrSize
;
2281 end
= hData
->mIrCount
* step
;
2282 n
= hData
->mIrPoints
;
2284 for(j
= 0;j
< end
;j
+= step
)
2286 for(i
= 0;i
< n
;i
++)
2287 maxLevel
= fmax(fabs(hData
->mHrirs
[j
+i
]), maxLevel
);
2289 maxLevel
= 1.01 * maxLevel
;
2290 for(j
= 0;j
< end
;j
+= step
)
2292 for(i
= 0;i
< n
;i
++)
2293 hData
->mHrirs
[j
+i
] /= maxLevel
;
2297 // Calculate the left-ear time delay using a spherical head model.
2298 static double CalcLTD(const double ev
, const double az
, const double rad
, const double dist
)
2300 double azp
, dlp
, l
, al
;
2302 azp
= asin(cos(ev
) * sin(az
));
2303 dlp
= sqrt((dist
*dist
) + (rad
*rad
) + (2.0*dist
*rad
*sin(azp
)));
2304 l
= sqrt((dist
*dist
) - (rad
*rad
));
2305 al
= (0.5 * M_PI
) + azp
;
2307 dlp
= l
+ (rad
* (al
- acos(rad
/ dist
)));
2308 return (dlp
/ 343.3);
2311 // Calculate the effective head-related time delays for each minimum-phase
2313 static void CalculateHrtds (const HeadModelT model
, const double radius
, HrirDataT
*hData
)
2315 double minHrtd
, maxHrtd
;
2321 for(e
= 0;e
< hData
->mEvCount
;e
++)
2323 for(a
= 0;a
< hData
->mAzCount
[e
];a
++)
2325 j
= hData
->mEvOffset
[e
] + a
;
2326 if(model
== HM_DATASET
)
2327 t
= hData
->mHrtds
[j
] * radius
/ hData
->mRadius
;
2329 t
= CalcLTD((-90.0 + (e
* 180.0 / (hData
->mEvCount
- 1))) * M_PI
/ 180.0,
2330 (a
* 360.0 / hData
->mAzCount
[e
]) * M_PI
/ 180.0,
2331 radius
, hData
->mDistance
);
2332 hData
->mHrtds
[j
] = t
;
2333 maxHrtd
= fmax(t
, maxHrtd
);
2334 minHrtd
= fmin(t
, minHrtd
);
2338 for(j
= 0;j
< hData
->mIrCount
;j
++)
2339 hData
->mHrtds
[j
] -= minHrtd
;
2340 hData
->mMaxHrtd
= maxHrtd
;
2344 // Process the data set definition to read and validate the data set metrics.
2345 static int ProcessMetrics(TokenReaderT
*tr
, const uint fftSize
, const uint truncSize
, HrirDataT
*hData
)
2347 int hasRate
= 0, hasPoints
= 0, hasAzimuths
= 0;
2348 int hasRadius
= 0, hasDistance
= 0;
2349 char ident
[MAX_IDENT_LEN
+1];
2355 while(!(hasRate
&& hasPoints
&& hasAzimuths
&& hasRadius
&& hasDistance
))
2357 TrIndication(tr
, & line
, & col
);
2358 if(!TrReadIdent(tr
, MAX_IDENT_LEN
, ident
))
2360 if(strcasecmp(ident
, "rate") == 0)
2364 TrErrorAt(tr
, line
, col
, "Redefinition of 'rate'.\n");
2367 if(!TrReadOperator(tr
, "="))
2369 if(!TrReadInt(tr
, MIN_RATE
, MAX_RATE
, &intVal
))
2371 hData
->mIrRate
= (uint
)intVal
;
2374 else if(strcasecmp(ident
, "points") == 0)
2377 TrErrorAt(tr
, line
, col
, "Redefinition of 'points'.\n");
2380 if(!TrReadOperator(tr
, "="))
2382 TrIndication(tr
, &line
, &col
);
2383 if(!TrReadInt(tr
, MIN_POINTS
, MAX_POINTS
, &intVal
))
2385 points
= (uint
)intVal
;
2386 if(fftSize
> 0 && points
> fftSize
)
2388 TrErrorAt(tr
, line
, col
, "Value exceeds the overridden FFT size.\n");
2391 if(points
< truncSize
)
2393 TrErrorAt(tr
, line
, col
, "Value is below the truncation size.\n");
2396 hData
->mIrPoints
= points
;
2399 hData
->mFftSize
= DEFAULT_FFTSIZE
;
2400 hData
->mIrSize
= 1 + (DEFAULT_FFTSIZE
/ 2);
2404 hData
->mFftSize
= fftSize
;
2405 hData
->mIrSize
= 1 + (fftSize
/ 2);
2406 if(points
> hData
->mIrSize
)
2407 hData
->mIrSize
= points
;
2411 else if(strcasecmp(ident
, "azimuths") == 0)
2415 TrErrorAt(tr
, line
, col
, "Redefinition of 'azimuths'.\n");
2418 if(!TrReadOperator(tr
, "="))
2420 hData
->mIrCount
= 0;
2421 hData
->mEvCount
= 0;
2422 hData
->mEvOffset
[0] = 0;
2425 if(!TrReadInt(tr
, MIN_AZ_COUNT
, MAX_AZ_COUNT
, &intVal
))
2427 hData
->mAzCount
[hData
->mEvCount
] = (uint
)intVal
;
2428 hData
->mIrCount
+= (uint
)intVal
;
2430 if(!TrIsOperator(tr
, ","))
2432 if(hData
->mEvCount
>= MAX_EV_COUNT
)
2434 TrError(tr
, "Exceeded the maximum of %d elevations.\n", MAX_EV_COUNT
);
2437 hData
->mEvOffset
[hData
->mEvCount
] = hData
->mEvOffset
[hData
->mEvCount
- 1] + ((uint
)intVal
);
2438 TrReadOperator(tr
, ",");
2440 if(hData
->mEvCount
< MIN_EV_COUNT
)
2442 TrErrorAt(tr
, line
, col
, "Did not reach the minimum of %d azimuth counts.\n", MIN_EV_COUNT
);
2447 else if(strcasecmp(ident
, "radius") == 0)
2451 TrErrorAt(tr
, line
, col
, "Redefinition of 'radius'.\n");
2454 if(!TrReadOperator(tr
, "="))
2456 if(!TrReadFloat(tr
, MIN_RADIUS
, MAX_RADIUS
, &fpVal
))
2458 hData
->mRadius
= fpVal
;
2461 else if(strcasecmp(ident
, "distance") == 0)
2465 TrErrorAt(tr
, line
, col
, "Redefinition of 'distance'.\n");
2468 if(!TrReadOperator(tr
, "="))
2470 if(!TrReadFloat(tr
, MIN_DISTANCE
, MAX_DISTANCE
, & fpVal
))
2472 hData
->mDistance
= fpVal
;
2477 TrErrorAt(tr
, line
, col
, "Expected a metric name.\n");
2480 TrSkipWhitespace (tr
);
2485 // Parse an index pair from the data set definition.
2486 static int ReadIndexPair(TokenReaderT
*tr
, const HrirDataT
*hData
, uint
*ei
, uint
*ai
)
2489 if(!TrReadInt(tr
, 0, (int)hData
->mEvCount
, &intVal
))
2492 if(!TrReadOperator(tr
, ","))
2494 if(!TrReadInt(tr
, 0, (int)hData
->mAzCount
[*ei
], &intVal
))
2500 // Match the source format from a given identifier.
2501 static SourceFormatT
MatchSourceFormat(const char *ident
)
2503 if(strcasecmp(ident
, "wave") == 0)
2505 if(strcasecmp(ident
, "bin_le") == 0)
2507 if(strcasecmp(ident
, "bin_be") == 0)
2509 if(strcasecmp(ident
, "ascii") == 0)
2514 // Match the source element type from a given identifier.
2515 static ElementTypeT
MatchElementType(const char *ident
)
2517 if(strcasecmp(ident
, "int") == 0)
2519 if(strcasecmp(ident
, "fp") == 0)
2524 // Parse and validate a source reference from the data set definition.
2525 static int ReadSourceRef(TokenReaderT
*tr
, SourceRefT
*src
)
2527 char ident
[MAX_IDENT_LEN
+1];
2531 TrIndication(tr
, &line
, &col
);
2532 if(!TrReadIdent(tr
, MAX_IDENT_LEN
, ident
))
2534 src
->mFormat
= MatchSourceFormat(ident
);
2535 if(src
->mFormat
== SF_NONE
)
2537 TrErrorAt(tr
, line
, col
, "Expected a source format.\n");
2540 if(!TrReadOperator(tr
, "("))
2542 if(src
->mFormat
== SF_WAVE
)
2544 if(!TrReadInt(tr
, 0, MAX_WAVE_CHANNELS
, &intVal
))
2546 src
->mType
= ET_NONE
;
2549 src
->mChannel
= (uint
)intVal
;
2554 TrIndication(tr
, &line
, &col
);
2555 if(!TrReadIdent(tr
, MAX_IDENT_LEN
, ident
))
2557 src
->mType
= MatchElementType(ident
);
2558 if(src
->mType
== ET_NONE
)
2560 TrErrorAt(tr
, line
, col
, "Expected a source element type.\n");
2563 if(src
->mFormat
== SF_BIN_LE
|| src
->mFormat
== SF_BIN_BE
)
2565 if(!TrReadOperator(tr
, ","))
2567 if(src
->mType
== ET_INT
)
2569 if(!TrReadInt(tr
, MIN_BIN_SIZE
, MAX_BIN_SIZE
, &intVal
))
2571 src
->mSize
= (uint
)intVal
;
2572 if(!TrIsOperator(tr
, ","))
2573 src
->mBits
= (int)(8*src
->mSize
);
2576 TrReadOperator(tr
, ",");
2577 TrIndication(tr
, &line
, &col
);
2578 if(!TrReadInt(tr
, -2147483647-1, 2147483647, &intVal
))
2580 if(abs(intVal
) < MIN_BIN_BITS
|| ((uint
)abs(intVal
)) > (8*src
->mSize
))
2582 TrErrorAt(tr
, line
, col
, "Expected a value of (+/-) %d to %d.\n", MIN_BIN_BITS
, 8*src
->mSize
);
2585 src
->mBits
= intVal
;
2590 TrIndication(tr
, &line
, &col
);
2591 if(!TrReadInt(tr
, -2147483647-1, 2147483647, &intVal
))
2593 if(intVal
!= 4 && intVal
!= 8)
2595 TrErrorAt(tr
, line
, col
, "Expected a value of 4 or 8.\n");
2598 src
->mSize
= (uint
)intVal
;
2602 else if(src
->mFormat
== SF_ASCII
&& src
->mType
== ET_INT
)
2604 if(!TrReadOperator(tr
, ","))
2606 if(!TrReadInt(tr
, MIN_ASCII_BITS
, MAX_ASCII_BITS
, &intVal
))
2609 src
->mBits
= intVal
;
2617 if(!TrIsOperator(tr
, ";"))
2621 TrReadOperator(tr
, ";");
2622 if(!TrReadInt (tr
, 0, 0x7FFFFFFF, &intVal
))
2624 src
->mSkip
= (uint
)intVal
;
2627 if(!TrReadOperator(tr
, ")"))
2629 if(TrIsOperator(tr
, "@"))
2631 TrReadOperator(tr
, "@");
2632 if(!TrReadInt(tr
, 0, 0x7FFFFFFF, &intVal
))
2634 src
->mOffset
= (uint
)intVal
;
2638 if(!TrReadOperator(tr
, ":"))
2640 if(!TrReadString(tr
, MAX_PATH_LEN
, src
->mPath
))
2645 // Process the list of sources in the data set definition.
2646 static int ProcessSources(const HeadModelT model
, TokenReaderT
*tr
, HrirDataT
*hData
)
2648 uint
*setCount
, *setFlag
;
2649 uint line
, col
, ei
, ai
;
2654 setCount
= (uint
*)calloc(hData
->mEvCount
, sizeof(uint
));
2655 setFlag
= (uint
*)calloc(hData
->mIrCount
, sizeof(uint
));
2656 hrir
= CreateArray(hData
->mIrPoints
);
2657 while(TrIsOperator(tr
, "["))
2659 TrIndication(tr
, & line
, & col
);
2660 TrReadOperator(tr
, "[");
2661 if(!ReadIndexPair(tr
, hData
, &ei
, &ai
))
2663 if(!TrReadOperator(tr
, "]"))
2665 if(setFlag
[hData
->mEvOffset
[ei
] + ai
])
2667 TrErrorAt(tr
, line
, col
, "Redefinition of source.\n");
2670 if(!TrReadOperator(tr
, "="))
2676 if(!ReadSourceRef(tr
, &src
))
2678 if(!LoadSource(&src
, hData
->mIrRate
, hData
->mIrPoints
, hrir
))
2681 if(model
== HM_DATASET
)
2682 AverageHrirOnset(hrir
, 1.0 / factor
, ei
, ai
, hData
);
2683 AverageHrirMagnitude(hrir
, 1.0 / factor
, ei
, ai
, hData
);
2685 if(!TrIsOperator(tr
, "+"))
2687 TrReadOperator(tr
, "+");
2689 setFlag
[hData
->mEvOffset
[ei
] + ai
] = 1;
2694 while(ei
< hData
->mEvCount
&& setCount
[ei
] < 1)
2696 if(ei
< hData
->mEvCount
)
2698 hData
->mEvStart
= ei
;
2699 while(ei
< hData
->mEvCount
&& setCount
[ei
] == hData
->mAzCount
[ei
])
2701 if(ei
>= hData
->mEvCount
)
2710 TrError(tr
, "Errant data at end of source list.\n");
2713 TrError(tr
, "Missing sources for elevation index %d.\n", ei
);
2716 TrError(tr
, "Missing source references.\n");
2725 /* Parse the data set definition and process the source data, storing the
2726 * resulting data set as desired. If the input name is NULL it will read
2727 * from standard input.
2729 static int ProcessDefinition(const char *inName
, const uint outRate
, const uint fftSize
, const int equalize
, const int surface
, const double limit
, const uint truncSize
, const HeadModelT model
, const double radius
, const OutputFormatT outFormat
, const int experimental
, const char *outName
)
2731 char rateStr
[8+1], expName
[MAX_PATH_LEN
];
2738 hData
.mSampleType
= ST_S24
;
2739 hData
.mChannelType
= CT_LEFTONLY
;
2740 hData
.mIrPoints
= 0;
2746 hData
.mDistance
= 0;
2747 fprintf(stdout
, "Reading HRIR definition...\n");
2750 fp
= fopen(inName
, "r");
2753 fprintf(stderr
, "Error: Could not open definition file '%s'\n", inName
);
2756 TrSetup(fp
, inName
, &tr
);
2761 TrSetup(fp
, "<stdin>", &tr
);
2763 if(!ProcessMetrics(&tr
, fftSize
, truncSize
, &hData
))
2769 hData
.mHrirs
= CreateArray(hData
.mIrCount
* hData
.mIrSize
);
2770 hData
.mHrtds
= CreateArray(hData
.mIrCount
);
2771 if(!ProcessSources(model
, &tr
, &hData
))
2773 DestroyArray(hData
.mHrtds
);
2774 DestroyArray(hData
.mHrirs
);
2783 dfa
= CreateArray(1 + (hData
.mFftSize
/2));
2784 fprintf(stdout
, "Calculating diffuse-field average...\n");
2785 CalculateDiffuseFieldAverage(&hData
, surface
, limit
, dfa
);
2786 fprintf(stdout
, "Performing diffuse-field equalization...\n");
2787 DiffuseFieldEqualize(dfa
, &hData
);
2790 fprintf(stdout
, "Performing minimum phase reconstruction...\n");
2791 ReconstructHrirs(&hData
);
2792 if(outRate
!= 0 && outRate
!= hData
.mIrRate
)
2794 fprintf(stdout
, "Resampling HRIRs...\n");
2795 ResampleHrirs(outRate
, &hData
);
2797 fprintf(stdout
, "Truncating minimum-phase HRIRs...\n");
2798 hData
.mIrPoints
= truncSize
;
2799 fprintf(stdout
, "Synthesizing missing elevations...\n");
2800 if(model
== HM_DATASET
)
2801 SynthesizeOnsets(&hData
);
2802 SynthesizeHrirs(&hData
);
2803 fprintf(stdout
, "Normalizing final HRIRs...\n");
2804 NormalizeHrirs(&hData
);
2805 fprintf(stdout
, "Calculating impulse delays...\n");
2806 CalculateHrtds(model
, (radius
> DEFAULT_CUSTOM_RADIUS
) ? radius
: hData
.mRadius
, &hData
);
2807 snprintf(rateStr
, 8, "%u", hData
.mIrRate
);
2808 StrSubst(outName
, "%r", rateStr
, MAX_PATH_LEN
, expName
);
2812 fprintf(stdout
, "Creating MHR data set file...\n");
2813 if(!StoreMhr(&hData
, experimental
, expName
))
2815 DestroyArray(hData
.mHrtds
);
2816 DestroyArray(hData
.mHrirs
);
2823 DestroyArray(hData
.mHrtds
);
2824 DestroyArray(hData
.mHrirs
);
2828 static void PrintHelp(const char *argv0
, FILE *ofile
)
2830 fprintf(ofile
, "Usage: %s <command> [<option>...]\n\n", argv0
);
2831 fprintf(ofile
, "Commands:\n");
2832 fprintf(ofile
, " -m, --make-mhr Makes an OpenAL Soft compatible HRTF data set.\n");
2833 fprintf(ofile
, " Defaults output to: ./oalsoft_hrtf_%%r.mhr\n");
2834 fprintf(ofile
, " -h, --help Displays this help information.\n\n");
2835 fprintf(ofile
, "Options:\n");
2836 fprintf(ofile
, " -r=<rate> Change the data set sample rate to the specified value and\n");
2837 fprintf(ofile
, " resample the HRIRs accordingly.\n");
2838 fprintf(ofile
, " -f=<points> Override the FFT window size (default: %u).\n", DEFAULT_FFTSIZE
);
2839 fprintf(ofile
, " -e={on|off} Toggle diffuse-field equalization (default: %s).\n", (DEFAULT_EQUALIZE
? "on" : "off"));
2840 fprintf(ofile
, " -s={on|off} Toggle surface-weighted diffuse-field average (default: %s).\n", (DEFAULT_SURFACE
? "on" : "off"));
2841 fprintf(ofile
, " -l={<dB>|none} Specify a limit to the magnitude range of the diffuse-field\n");
2842 fprintf(ofile
, " average (default: %.2f).\n", DEFAULT_LIMIT
);
2843 fprintf(ofile
, " -w=<points> Specify the size of the truncation window that's applied\n");
2844 fprintf(ofile
, " after minimum-phase reconstruction (default: %u).\n", DEFAULT_TRUNCSIZE
);
2845 fprintf(ofile
, " -d={dataset| Specify the model used for calculating the head-delay timing\n");
2846 fprintf(ofile
, " sphere} values (default: %s).\n", ((DEFAULT_HEAD_MODEL
== HM_DATASET
) ? "dataset" : "sphere"));
2847 fprintf(ofile
, " -c=<size> Use a customized head radius measured ear-to-ear in meters.\n");
2848 fprintf(ofile
, " -i=<filename> Specify an HRIR definition file to use (defaults to stdin).\n");
2849 fprintf(ofile
, " -o=<filename> Specify an output file. Overrides command-selected default.\n");
2850 fprintf(ofile
, " Use of '%%r' will be substituted with the data set sample rate.\n");
2853 // Standard command line dispatch.
2854 int main(const int argc
, const char *argv
[])
2856 const char *inName
= NULL
, *outName
= NULL
;
2857 OutputFormatT outFormat
;
2858 uint outRate
, fftSize
;
2859 int equalize
, surface
;
2868 if(argc
< 2 || strcmp(argv
[1], "--help") == 0 || strcmp(argv
[1], "-h") == 0)
2870 fprintf(stdout
, "HRTF Processing and Composition Utility\n\n");
2871 PrintHelp(argv
[0], stdout
);
2875 if(strcmp(argv
[1], "--make-mhr") == 0 || strcmp(argv
[1], "-m") == 0)
2877 outName
= "./oalsoft_hrtf_%r.mhr";
2882 fprintf(stderr
, "Error: Invalid command '%s'.\n\n", argv
[1]);
2883 PrintHelp(argv
[0], stderr
);
2889 equalize
= DEFAULT_EQUALIZE
;
2890 surface
= DEFAULT_SURFACE
;
2891 limit
= DEFAULT_LIMIT
;
2892 truncSize
= DEFAULT_TRUNCSIZE
;
2893 model
= DEFAULT_HEAD_MODEL
;
2894 radius
= DEFAULT_CUSTOM_RADIUS
;
2900 if(strncmp(argv
[argi
], "-r=", 3) == 0)
2902 outRate
= strtoul(&argv
[argi
][3], &end
, 10);
2903 if(end
[0] != '\0' || outRate
< MIN_RATE
|| outRate
> MAX_RATE
)
2905 fprintf(stderr
, "Error: Expected a value from %u to %u for '-r'.\n", MIN_RATE
, MAX_RATE
);
2909 else if(strncmp(argv
[argi
], "-f=", 3) == 0)
2911 fftSize
= strtoul(&argv
[argi
][3], &end
, 10);
2912 if(end
[0] != '\0' || (fftSize
&(fftSize
-1)) || fftSize
< MIN_FFTSIZE
|| fftSize
> MAX_FFTSIZE
)
2914 fprintf(stderr
, "Error: Expected a power-of-two value from %u to %u for '-f'.\n", MIN_FFTSIZE
, MAX_FFTSIZE
);
2918 else if(strncmp(argv
[argi
], "-e=", 3) == 0)
2920 if(strcmp(&argv
[argi
][3], "on") == 0)
2922 else if(strcmp(&argv
[argi
][3], "off") == 0)
2926 fprintf(stderr
, "Error: Expected 'on' or 'off' for '-e'.\n");
2930 else if(strncmp(argv
[argi
], "-s=", 3) == 0)
2932 if(strcmp(&argv
[argi
][3], "on") == 0)
2934 else if(strcmp(&argv
[argi
][3], "off") == 0)
2938 fprintf(stderr
, "Error: Expected 'on' or 'off' for '-s'.\n");
2942 else if(strncmp(argv
[argi
], "-l=", 3) == 0)
2944 if(strcmp(&argv
[argi
][3], "none") == 0)
2948 limit
= strtod(&argv
[argi
] [3], &end
);
2949 if(end
[0] != '\0' || limit
< MIN_LIMIT
|| limit
> MAX_LIMIT
)
2951 fprintf(stderr
, "Error: Expected 'none' or a value from %.2f to %.2f for '-l'.\n", MIN_LIMIT
, MAX_LIMIT
);
2956 else if(strncmp(argv
[argi
], "-w=", 3) == 0)
2958 truncSize
= strtoul(&argv
[argi
][3], &end
, 10);
2959 if(end
[0] != '\0' || truncSize
< MIN_TRUNCSIZE
|| truncSize
> MAX_TRUNCSIZE
|| (truncSize
%MOD_TRUNCSIZE
))
2961 fprintf(stderr
, "Error: Expected a value from %u to %u in multiples of %u for '-w'.\n", MIN_TRUNCSIZE
, MAX_TRUNCSIZE
, MOD_TRUNCSIZE
);
2965 else if(strncmp(argv
[argi
], "-d=", 3) == 0)
2967 if(strcmp(&argv
[argi
][3], "dataset") == 0)
2969 else if(strcmp(&argv
[argi
][3], "sphere") == 0)
2973 fprintf(stderr
, "Error: Expected 'dataset' or 'sphere' for '-d'.\n");
2977 else if(strncmp(argv
[argi
], "-c=", 3) == 0)
2979 radius
= strtod(&argv
[argi
][3], &end
);
2980 if(end
[0] != '\0' || radius
< MIN_CUSTOM_RADIUS
|| radius
> MAX_CUSTOM_RADIUS
)
2982 fprintf(stderr
, "Error: Expected a value from %.2f to %.2f for '-c'.\n", MIN_CUSTOM_RADIUS
, MAX_CUSTOM_RADIUS
);
2986 else if(strncmp(argv
[argi
], "-i=", 3) == 0)
2987 inName
= &argv
[argi
][3];
2988 else if(strncmp(argv
[argi
], "-o=", 3) == 0)
2989 outName
= &argv
[argi
][3];
2990 else if(strcmp(argv
[argi
], "--experimental") == 0)
2994 fprintf(stderr
, "Error: Invalid option '%s'.\n", argv
[argi
]);
2999 if(!ProcessDefinition(inName
, outRate
, fftSize
, equalize
, surface
, limit
,
3000 truncSize
, model
, radius
, outFormat
, experimental
,
3003 fprintf(stdout
, "Operation completed.\n");