1 /* ----------------------------------------------------------------------
2 * Copyright (C) 2010-2012 ARM Limited. All rights reserved.
3 *
4 * $Date: 17. January 2013
5 * $Revision: V1.4.0
6 *
7 * Project: CMSIS DSP Library
8 * Title: arm_graphic_equalizer_example_q31.c
9 *
10 * Description: Example showing an audio graphic equalizer constructed
11 * out of Biquad filters.
12 *
13 * Target Processor: Cortex-M4/Cortex-M3
14 *
15 * Redistribution and use in source and binary forms, with or without
16 * modification, are permitted provided that the following conditions
17 * are met:
18 * - Redistributions of source code must retain the above copyright
19 * notice, this list of conditions and the following disclaimer.
20 * - Redistributions in binary form must reproduce the above copyright
21 * notice, this list of conditions and the following disclaimer in
22 * the documentation and/or other materials provided with the
23 * distribution.
24 * - Neither the name of ARM LIMITED nor the names of its contributors
25 * may be used to endorse or promote products derived from this
26 * software without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
31 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
32 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
33 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
34 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
35 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
36 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
38 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
39 * POSSIBILITY OF SUCH DAMAGE.
40 * -------------------------------------------------------------------- */
41
42 /**
43 * @addtogroup groupExamples
44 * @{
45 *
46 * @defgroup GEQ5Band Graphic Audio Equalizer Example
47 *
48 * \par Description:
49 * \par
50 * This example demonstrates how a 5-band graphic equalizer can be constructed
51 * using the Biquad cascade functions.
52 * A graphic equalizer is used in audio applications to vary the tonal quality
53 * of the audio.
54 *
55 * \par Block Diagram:
56 * \par
57 * The design is based on a cascade of 5 filter sections.
58 * \image html GEQ_signalflow.gif
59 * Each filter section is 4th order and consists of a cascade of two Biquads.
60 * Each filter has a nominal gain of 0 dB (1.0 in linear units) and
61 * boosts or cuts signals within a specific frequency range.
62 * The edge frequencies between the 5 bands are 100, 500, 2000, and 6000 Hz.
63 * Each band has an adjustable boost or cut in the range of +/- 9 dB.
64 * For example, the band that extends from 500 to 2000 Hz has the response shown below:
65 * \par
66 * \image html GEQ_bandresponse.gif
67 * \par
68 * With 1 dB steps, each filter has a total of 19 different settings.
69 * The filter coefficients for all possible 19 settings were precomputed
70 * in MATLAB and stored in a table. With 5 different tables, there are
71 * a total of 5 x 19 = 95 different 4th order filters.
72 * All 95 responses are shown below:
73 * \par
74 * \image html GEQ_allbandresponse.gif
75 * \par
76 * Each 4th order filter has 10 coefficents for a grand total of 950 different filter
77 * coefficients that must be tabulated. The input and output data is in Q31 format.
78 * For better noise performance, the two low frequency bands are implemented using the high
79 * precision 32x64-bit Biquad filters. The remaining 3 high frequency bands use standard
80 * 32x32-bit Biquad filters. The input signal used in the example is a logarithmic chirp.
81 * \par
82 * \image html GEQ_inputchirp.gif
83 * \par
84 * The array <code>bandGains</code> specifies the gain in dB to apply in each band.
85 * For example, if <code>bandGains={0, -3, 6, 4, -6};</code> then the output signal will be:
86 * \par
87 * \image html GEQ_outputchirp.gif
88 * \par
89 * \note The output chirp signal follows the gain or boost of each band.
90 * \par
91 *
92 * \par Variables Description:
93 * \par
94 * \li \c testInput_f32 points to the input data
95 * \li \c testRefOutput_f32 points to the reference output data
96 * \li \c testOutput points to the test output data
97 * \li \c inputQ31 temporary input buffer
98 * \li \c outputQ31 temporary output buffer
99 * \li \c biquadStateBand1Q31 points to state buffer for band1
100 * \li \c biquadStateBand2Q31 points to state buffer for band2
101 * \li \c biquadStateBand3Q31 points to state buffer for band3
102 * \li \c biquadStateBand4Q31 points to state buffer for band4
103 * \li \c biquadStateBand5Q31 points to state buffer for band5
104 * \li \c coeffTable points to coefficient buffer for all bands
105 * \li \c gainDB gain buffer which has gains applied for all the bands
106 *
107 * \par CMSIS DSP Software Library Functions Used:
108 * \par
109 * - arm_biquad_cas_df1_32x64_init_q31()
110 * - arm_biquad_cas_df1_32x64_q31()
111 * - arm_biquad_cascade_df1_init_q31()
112 * - arm_biquad_cascade_df1_q31()
113 * - arm_scale_q31()
114 * - arm_scale_f32()
115 * - arm_float_to_q31()
116 * - arm_q31_to_float()
117 *
118 * <b> Refer </b>
119 * \link arm_graphic_equalizer_example_q31.c \endlink
120 *
121 * \example arm_graphic_equalizer_example_q31.c
122 *
123 * @} */
124
125 #include "arm_math.h"
126 #include "math_helper.h"
127
128 #if defined(SEMIHOSTING)
129 #include <stdio.h>
130 #endif
131
132 /* Length of the overall data in the test */
133 #define TESTLENGTH 320
134
135 /* Block size for the underlying processing */
136 #define BLOCKSIZE 32
137
138 /* Total number of blocks to run */
139 #define NUMBLOCKS (TESTLENGTH/BLOCKSIZE)
140
141 /* Number of 2nd order Biquad stages per filter */
142 #define NUMSTAGES 2
143
144 #define SNR_THRESHOLD_F32 98
145
146 /* -------------------------------------------------------------------
147 * External Declarations for Input and Output buffers
148 * ------------------------------------------------------------------- */
149
150 extern float32_t testInput_f32[TESTLENGTH];
151 static float32_t testOutput[TESTLENGTH];
152
153 extern float32_t testRefOutput_f32[TESTLENGTH];
154
155 /* ----------------------------------------------------------------------
156 ** Q31 state buffers for Band1, Band2, Band3, Band4, Band5
157 ** ------------------------------------------------------------------- */
158
159 static q63_t biquadStateBand1Q31[4 * 2];
160 static q63_t biquadStateBand2Q31[4 * 2];
161 static q31_t biquadStateBand3Q31[4 * 2];
162 static q31_t biquadStateBand4Q31[4 * 2];
163 static q31_t biquadStateBand5Q31[4 * 2];
164
165 /* ----------------------------------------------------------------------
166 ** Q31 input and output buffers
167 ** ------------------------------------------------------------------- */
168
169 q31_t inputQ31[BLOCKSIZE];
170 q31_t outputQ31[BLOCKSIZE];
171
172 /* ----------------------------------------------------------------------
173 ** Entire coefficient table. There are 10 coefficients per 4th order Biquad
174 ** cascade filter. The first 10 coefficients correspond to the -9 dB gain
175 ** setting of band 1; the next 10 coefficient correspond to the -8 dB gain
176 ** setting of band 1; and so on. There are 10*19=190 coefficients in total
177 ** for band 1 (gains = -9, -8, -7, ..., 9). After this come the 190 coefficients
178 ** for band 2.
179 **
180 ** The coefficients are in Q29 format and require a postShift of 2.
181 ** ------------------------------------------------------------------- */
182
183 const q31_t coeffTable[950] = {
184
185 /* Band 1, -9 dB gain */
186 535576962, -1071153923, 535576962, 1073741824, -536870912, 535576962, -1063501998, 527979313, 1060865294, -524146981,
187 /* Band 1, -8 dB gain */
188 535723226, -1071446451, 535723226, 1073741824, -536870912, 535723226, -1063568947, 527903217, 1061230578, -524503778,
189 535868593, -1071737186, 535868593, 1073741824, -536870912, 535868593, -1063627467, 527819780, 1061585502, -524850686,
190 536013181, -1072026363, 536013181, 1073741824, -536870912, 536013181, -1063677598, 527728935, 1061930361, -525187972,
191 536157109, -1072314217, 536157109, 1073741824, -536870912, 536157109, -1063719372, 527630607, 1062265438, -525515897,
192 536300492, -1072600983, 536300492, 1073741824, -536870912, 536300492, -1063752815, 527524720, 1062591011, -525834716,
193 536443447, -1072886894, 536443447, 1073741824, -536870912, 536443447, -1063777945, 527411186, 1062907350, -526144676,
194 536586091, -1073172183, 536586091, 1073741824, -536870912, 536586091, -1063794775, 527289917, 1063214717, -526446017,
195 536728541, -1073457082, 536728541, 1073741824, -536870912, 536728541, -1063803308, 527160815, 1063513366, -526738975,
196 536870912, -1073741824, 536870912, 1073741824, -536870912, 536870912, -1063803543, 527023777, 1063803543, -527023777,
197 537013321, -1074026642, 537013321, 1073741824, -536870912, 537013321, -1063795470, 526878696, 1064085490, -527300648,
198 537155884, -1074311768, 537155884, 1073741824, -536870912, 537155884, -1063779073, 526725455, 1064359439, -527569803,
199 537298718, -1074597435, 537298718, 1073741824, -536870912, 537298718, -1063754328, 526563934, 1064625617, -527831454,
200 537441939, -1074883878, 537441939, 1073741824, -536870912, 537441939, -1063721205, 526394005, 1064884245, -528085806,
201 537585666, -1075171331, 537585666, 1073741824, -536870912, 537585666, -1063679666, 526215534, 1065135536, -528333059,
202 537730015, -1075460030, 537730015, 1073741824, -536870912, 537730015, -1063629666, 526028380, 1065379699, -528573409,
203 537875106, -1075750212, 537875106, 1073741824, -536870912, 537875106, -1063571152, 525832396, 1065616936, -528807045,
204 538021057, -1076042114, 538021057, 1073741824, -536870912, 538021057, -1063504065, 525627429, 1065847444, -529034151,
205 538167989, -1076335977, 538167989, 1073741824, -536870912, 538167989, -1063428338, 525413317, 1066071412, -529254907,
206
207 /* Band 2, -9 dB gain */
208 531784976, -1055497692, 523873415, 1066213307, -529420241, 531784976, -1040357886, 509828014, 1028908252, -494627367,
209 /* Band 2, -8 dB gain */
210 532357636, -1056601982, 524400080, 1066115844, -529326645, 532357636, -1040623406, 509562600, 1030462237, -496062122,
211 532927392, -1057707729, 524931110, 1066024274, -529239070, 532927392, -1040848253, 509262081, 1031969246, -497457090,
212 533494678, -1058816094, 525467240, 1065939047, -529157961, 533494678, -1041032161, 508925950, 1033429976, -498812573,
213 534059929, -1059928204, 526009170, 1065860582, -529083734, 534059929, -1041174868, 508553717, 1034845124, -500128887,
214 534623580, -1061045148, 526557561, 1065789260, -529016764, 534623580, -1041276126, 508144920, 1036215393, -501406373,
215 535186068, -1062167969, 527113032, 1065725420, -528957385, 535186068, -1041335703, 507699125, 1037541500, -502645399,
216 535747827, -1063297666, 527676151, 1065669351, -528905879, 535747827, -1041353386, 507215934, 1038824183, -503846368,
217 536309295, -1064435183, 528247436, 1065621289, -528862476, 536309295, -1041328990, 506694984, 1040064203, -505009724,
218 536870912, -1065581413, 528827349, 1065581413, -528827349, 536870912, -1041262354, 506135953, 1041262354, -506135953,
219 537433117, -1066737194, 529416295, 1065549847, -528800610, 537433117, -1041153346, 505538564, 1042419457, -507225588,
220 537996352, -1067903307, 530014622, 1065526651, -528782316, 537996352, -1041001864, 504902578, 1043536370, -508279208,
221 538561061, -1069080480, 530622620, 1065511830, -528772462, 538561061, -1040807833, 504227800, 1044613981, -509297437,
222 539127690, -1070269387, 531240527, 1065505333, -528770987, 539127690, -1040571205, 503514074, 1045653211, -510280946,
223 539696690, -1071470656, 531868525, 1065507054, -528777778, 539696690, -1040291951, 502761277, 1046655011, -511230450,
224 540268512, -1072684867, 532506750, 1065516837, -528792672, 540268512, -1039970063, 501969320, 1047620358, -512146700,
225 540843613, -1073912567, 533155297, 1065534483, -528815459, 540843613, -1039605542, 501138139, 1048550251, -513030484,
226 541422451, -1075154268, 533814224, 1065559750, -528845892, 541422451, -1039198394, 500267687, 1049445708, -513882621,
227 542005489, -1076410460, 534483561, 1065592362, -528883686, 542005489, -1038748624, 499357932, 1050307760, -514703956,
228 518903861, -1001986830, 486725277, 1037235801, -502367695, 518903861, -945834422, 446371043, 902366163, -400700571,
229 520899989, -1005630916, 488289126, 1036926846, -502147311, 520899989, -946490935, 445581846, 907921945, -404936158,
230 522893209, -1009290002, 489869792, 1036650484, -501961419, 522893209, -947006359, 444685310, 913306106, -409075225,
231 524884763, -1012968199, 491470256, 1036407567, -501810737, 524884763, -947377809, 443679533, 918521018, -413116221,
232 526875910, -1016669649, 493093518, 1036198712, -501695739, 526875910, -947602324, 442562672, 923569247, -417057897,
233 528867927, -1020398503, 494742575, 1036024293, -501616651, 528867927, -947676875, 441332970, 928453558, -420899319,
234 530862111, -1024158905, 496420407, 1035884447, -501573457, 530862111, -947598385, 439988777, 933176909, -424639872,
235 532859778, -1027954970, 498129955, 1035779077, -501565907, 532859778, -947363742, 438528571, 937742446, -428279254,
236 534862260, -1031790763, 499874098, 1035707863, -501593525, 534862260, -946969823, 436950987, 942153486, -431817474,
237 536870912, -1035670279, 501655630, 1035670279, -501655630, 536870912, -946413508, 435254839, 946413508, -435254839,
238 538887107, -1039597419, 503477238, 1035665609, -501751354, 538887107, -945691703, 433439146, 950526127, -438591937,
239 540912240, -1043575967, 505341475, 1035692963, -501879659, 540912240, -944801359, 431503152, 954495080, -441829621,
240 542947726, -1047609569, 507250741, 1035751307, -502039364, 542947726, -943739490, 429446349, 958324201, -444968987,
241 544995000, -1051701717, 509207261, 1035839473, -502229165, 544995000, -942503190, 427268492, 962017400, -448011351,
242 547055523, -1055855728, 511213065, 1035956193, -502447657, 547055523, -941089647, 424969617, 965578640, -450958226,
243 549130774, -1060074734, 513269973, 1036100110, -502693359, 549130774, -939496155, 422550049, 969011913, -453811298,
244 551222259, -1064361672, 515379585, 1036269804, -502964731, 551222259, -937720119, 420010407, 972321228, -456572401,
245 553331507, -1068719280, 517543273, 1036463810, -503260192, 553331507, -935759057, 417351601, 975510582, -459243495,
246 555460072, -1073150100, 519762181, 1036680633, -503578144, 555460072, -933610600, 414574832, 978583948, -461826644,
247 494084017, -851422604, 404056273, 930151631, -423619864, 494084017, -673714108, 339502486, 561843007, -265801750,
248 498713542, -859177141, 406587077, 929211656, -423786402, 498713542, -673274906, 338185129, 573719128, -272222942,
249 503369016, -867012190, 409148384, 928362985, -424054784, 503369016, -672533059, 336693984, 585290277, -278599028,
250 508052536, -874935599, 411746438, 927604291, -424422151, 508052536, -671478538, 335026905, 596558312, -284920289,
251 512766286, -882955583, 414387826, 926933782, -424885216, 512766286, -670100998, 333182045, 607525792, -291177811,
252 517512534, -891080712, 417079474, 926349262, -425440318, 517512534, -668389789, 331157902, 618195914, -297363485,
253 522293635, -899319903, 419828635, 925848177, -426083491, 522293635, -666333963, 328953368, 628572440, -303470012,
254 527112032, -907682405, 422642886, 925427679, -426810526, 527112032, -663922286, 326567785, 638659631, -309490882,
255 531970251, -916177781, 425530105, 925084675, -427617023, 531970251, -661143261, 324000998, 648462180, -315420352,
256 536870912, -924815881, 428498454, 924815881, -428498454, 536870912, -657985147, 321253420, 657985147, -321253420,
257 541816719, -933606817, 431556352, 924617870, -429450209, 541816719, -654435997, 318326093, 667233900, -326985786,
258 546810467, -942560921, 434712438, 924487114, -430467639, 546810467, -650483688, 315220754, 676214053, -332613816,
259 551855042, -951688708, 437975532, 924420027, -431546101, 551855042, -646115970, 311939896, 684931422, -338134495,
260 556953421, -961000826, 441354588, 924413001, -432680993, 556953421, -641320513, 308486839, 693391970, -343545389,
261 562108672, -970508005, 444858642, 924462435, -433867780, 562108672, -636084967, 304865786, 701601770, -348844597,
262 567323959, -980220994, 448496743, 924564764, -435102022, 567323959, -630397020, 301081886, 709566963, -354030710,
263 572602539, -990150500, 452277894, 924716482, -436379394, 572602539, -624244471, 297141281, 717293726, -359102767,
264 577947763, -1000307125, 456210977, 924914158, -437695705, 577947763, -617615296, 293051155, 724788245, -364060214,
265 583363084, -1010701292, 460304674, 925154455, -439046908, 583363084, -610497723, 288819761, 732056685, -368902865,
266 387379495, -506912469, 196933274, 840112184, -347208270, 387379495, 506912469, 196933274, -840112184, -347208270,
267 401658082, -532275898, 207149427, 833765363, -343175316, 401658082, 532275898, 207149427, -833765363, -343175316,
268 416472483, -558722695, 217902617, 827270154, -339107319, 416472483, 558722695, 217902617, -827270154, -339107319,
269 431841949, -586290861, 229212798, 820624988, -335007540, 431841949, 586290861, 229212798, -820624988, -335007540,
270 447786335, -615019650, 241100489, 813828443, -330879528, 447786335, 615019650, 241100489, -813828443, -330879528,
271 464326111, -644949597, 253586805, 806879270, -326727141, 464326111, 644949597, 253586805, -806879270, -326727141,
272 481482377, -676122557, 266693475, 799776409, -322554559, 481482377, 676122557, 266693475, -799776409, -322554559,
273 499276882, -708581728, 280442865, 792519013, -318366296, 499276882, 708581728, 280442865, -792519013, -318366296,
274 517732032, -742371685, 294857996, 785106465, -314167221, 517732032, 742371685, 294857996, -785106465, -314167221,
275 536870912, -777538408, 309962566, 777538408, -309962566, 536870912, 777538408, 309962566, -777538408, -309962566,
276 556717294, -814129313, 325780968, 769814766, -305757943, 556717294, 814129313, 325780968, -769814766, -305757943,
277 577295658, -852193284, 342338310, 761935777, -301559360, 577295658, 852193284, 342338310, -761935777, -301559360,
278 598631206, -891780698, 359660433, 753902014, -297373230, 598631206, 891780698, 359660433, -753902014, -297373230,
279 620749877, -932943463, 377773927, 745714425, -293206383, 620749877, 932943463, 377773927, -745714425, -293206383,
280 643678365, -975735041, 396706151, 737374355, -289066077, 643678365, 975735041, 396706151, -737374355, -289066077,
281 667444134, -1020210487, 416485252, 728883588, -284960004, 667444134, 1020210487, 416485252, -728883588, -284960004,
282 692075438, -1066426476, 437140179, 720244375, -280896294, 692075438, 1066426476, 437140179, -720244375, -280896294,
283 717601336, -1114441339, 458700704, 711459472, -276883515, 717601336, 1114441339, 458700704, -711459472, -276883515,
284 744051710, -1164315096, 481197437, 702532174, -272930673, 744051710, 1164315096, 481197437, -702532174, -272930673
285
286 };
287
288 /* ----------------------------------------------------------------------
289 ** Desired gains, in dB, per band
290 ** ------------------------------------------------------------------- */
291
292 int gainDB[5] = {0, -3, 6, 4, -6};
293
294 float32_t snr;
295
296
297 /* ----------------------------------------------------------------------
298 * Graphic equalizer Example
299 * ------------------------------------------------------------------- */
300
main(void)301 int32_t main(void)
302 {
303 float32_t *inputF32, *outputF32;
304 arm_biquad_cas_df1_32x64_ins_q31 S1;
305 arm_biquad_cas_df1_32x64_ins_q31 S2;
306 arm_biquad_casd_df1_inst_q31 S3;
307 arm_biquad_casd_df1_inst_q31 S4;
308 arm_biquad_casd_df1_inst_q31 S5;
309 int i;
310 int32_t status;
311
312 inputF32 = &testInput_f32[0];
313 outputF32 = &testOutput[0];
314
315 /* Initialize the state and coefficient buffers for all Biquad sections */
316
317 arm_biquad_cas_df1_32x64_init_q31(&S1, NUMSTAGES,
318 (q31_t *) &coeffTable[190*0 + 10*(gainDB[0] + 9)],
319 &biquadStateBand1Q31[0], 2);
320
321 arm_biquad_cas_df1_32x64_init_q31(&S2, NUMSTAGES,
322 (q31_t *) &coeffTable[190*1 + 10*(gainDB[1] + 9)],
323 &biquadStateBand2Q31[0], 2);
324
325 arm_biquad_cascade_df1_init_q31(&S3, NUMSTAGES,
326 (q31_t *) &coeffTable[190*2 + 10*(gainDB[2] + 9)],
327 &biquadStateBand3Q31[0], 2);
328
329 arm_biquad_cascade_df1_init_q31(&S4, NUMSTAGES,
330 (q31_t *) &coeffTable[190*3 + 10*(gainDB[3] + 9)],
331 &biquadStateBand4Q31[0], 2);
332
333 arm_biquad_cascade_df1_init_q31(&S5, NUMSTAGES,
334 (q31_t *) &coeffTable[190*4 + 10*(gainDB[4] + 9)],
335 &biquadStateBand5Q31[0], 2);
336
337
338 /* Call the process functions and needs to change filter coefficients
339 for varying the gain of each band */
340
341 for(i=0; i < NUMBLOCKS; i++)
342 {
343
344 /* ----------------------------------------------------------------------
345 ** Convert block of input data from float to Q31
346 ** ------------------------------------------------------------------- */
347
348 arm_float_to_q31(inputF32 + (i*BLOCKSIZE), inputQ31, BLOCKSIZE);
349
350 /* ----------------------------------------------------------------------
351 ** Scale down by 1/8. This provides additional headroom so that the
352 ** graphic EQ can apply gain.
353 ** ------------------------------------------------------------------- */
354
355 arm_scale_q31(inputQ31, 0x7FFFFFFF, -3, inputQ31, BLOCKSIZE);
356
357 /* ----------------------------------------------------------------------
358 ** Call the Q31 Biquad Cascade DF1 32x64 process function for band1, band2
359 ** ------------------------------------------------------------------- */
360
361 arm_biquad_cas_df1_32x64_q31(&S1, inputQ31, outputQ31, BLOCKSIZE);
362 arm_biquad_cas_df1_32x64_q31(&S2, outputQ31, outputQ31, BLOCKSIZE);
363
364 /* ----------------------------------------------------------------------
365 ** Call the Q31 Biquad Cascade DF1 process function for band3, band4, band5
366 ** ------------------------------------------------------------------- */
367
368 arm_biquad_cascade_df1_q31(&S3, outputQ31, outputQ31, BLOCKSIZE);
369 arm_biquad_cascade_df1_q31(&S4, outputQ31, outputQ31, BLOCKSIZE);
370 arm_biquad_cascade_df1_q31(&S5, outputQ31, outputQ31, BLOCKSIZE);
371
372 /* ----------------------------------------------------------------------
373 ** Convert Q31 result back to float
374 ** ------------------------------------------------------------------- */
375
376 arm_q31_to_float(outputQ31, outputF32 + (i * BLOCKSIZE), BLOCKSIZE);
377
378 /* ----------------------------------------------------------------------
379 ** Scale back up
380 ** ------------------------------------------------------------------- */
381
382 arm_scale_f32(outputF32 + (i * BLOCKSIZE), 8.0f, outputF32 + (i * BLOCKSIZE), BLOCKSIZE);
383 };
384
385 snr = arm_snr_f32(testRefOutput_f32, testOutput, TESTLENGTH);
386
387 status = (snr < SNR_THRESHOLD_F32) ? ARM_MATH_TEST_FAILURE : ARM_MATH_SUCCESS;
388
389 if (status != ARM_MATH_SUCCESS)
390 {
391 #if defined (SEMIHOSTING)
392 printf("FAILURE\n");
393 #else
394 while (1); /* main function does not return */
395 #endif
396 }
397 else
398 {
399 #if defined (SEMIHOSTING)
400 printf("SUCCESS\n");
401 #else
402 while (1); /* main function does not return */
403 #endif
404 }
405
406 }
407
408 /** \endlink */
409
410
411
412
