Fix bug in DTMF generation where events with level > 36 would be ignored.

webrtc/modules/audio_coding/neteq/dtmf_tone_generator.cc

 /*
  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 12 matching lines @@
 // respectively, on the keypad as illustrated below.
 //
 //          1209 Hz  1336 Hz  1477 Hz  1633 Hz
 // 697 Hz      1        2        3       12
 // 770 Hz      4        5        6       13
 // 852 Hz      7        8        9       14
 // 941 Hz     10        0       11       15
 
 #include "webrtc/modules/audio_coding/neteq/dtmf_tone_generator.h"
 
-#include <assert.h>
+#include "webrtc/base/arraysize.h"
+#include "webrtc/base/checks.h"
 
 namespace webrtc {
 
 // The filter coefficient a = 2*cos(2*pi*f/fs) for the low frequency tone, for
 // sample rates fs = {8000, 16000, 32000, 48000} Hz, and events 0 through 15.
 // Values are in Q14.
 const int DtmfToneGenerator::kCoeff1[4][16] = {
     { 24219, 27980, 27980, 27980, 26956, 26956, 26956, 25701, 25701, 25701,
       24219, 24219, 27980, 26956, 25701, 24219 },
     { 30556, 31548, 31548, 31548, 31281, 31281, 31281, 30951, 30951, 30951,
@@ skipping 35 matching lines @@
 const int DtmfToneGenerator::kInitValue2[4][16] = {
     { 14206, 13323, 14206, 15021, 13323, 14206, 15021, 13323, 14206, 15021,
       13323, 15021, 15708, 15708, 15708, 15708},
     { 8207, 7490, 8207, 8979, 7490, 8207, 8979, 7490, 8207, 8979, 7490, 8979,
       9801, 9801, 9801, 9801},
     { 4249, 3853, 4249, 4685, 3853, 4249, 4685, 3853, 4249, 4685, 3853, 4685,
       5164, 5164, 5164, 5164},
     { 2851, 2582, 2851, 3148, 2582, 2851, 3148, 2582, 2851, 3148, 2582, 3148,
       3476, 3476, 3476, 3476} };
 
-// Amplitude multipliers for volume values 0 through 36, corresponding to
-// 0 dBm0 through -36 dBm0. Values are in Q14.
-const int DtmfToneGenerator::kAmplitude[37] = {
+// Amplitude multipliers for volume values 0 through 63, corresponding to
+// 0 dBm0 through -63 dBm0. Values are in Q14.
+// for a in range(0, 64):
+//   print round(16141.0 * 10**(-float(a)/20))
+const int DtmfToneGenerator::kAmplitude[64] = {
     16141, 14386, 12821, 11427, 10184, 9077, 8090, 7210, 6426, 5727, 5104, 4549,
     4054, 3614, 3221, 2870, 2558, 2280, 2032, 1811, 1614, 1439, 1282, 1143,
-    1018, 908, 809, 721, 643, 573, 510, 455, 405, 361, 322, 287, 256 };
+    1018, 908, 809, 721, 643, 573, 510, 455, 405, 361, 322, 287, 256, 228, 203,
+    181, 161, 144, 128, 114, 102, 91, 81, 72, 64, 57, 51, 45, 41, 36, 32, 29,
+    26, 23, 20, 18, 16, 14, 13, 11 };
 
 // Constructor.
 DtmfToneGenerator::DtmfToneGenerator()
     : initialized_(false),
       coeff1_(0),
       coeff2_(0),
       amplitude_(0) {
 }
 
 // Initialize the DTMF generator with sample rate fs Hz (8000, 16000, 32000,
 // 48000), event (0-15) and attenuation (0-36 dB).
 // Returns 0 on success, otherwise an error code.
 int DtmfToneGenerator::Init(int fs, int event, int attenuation) {
   initialized_ = false;
-  int fs_index;
+  size_t fs_index;
   if (fs == 8000) {
     fs_index = 0;
   } else if (fs == 16000) {
     fs_index = 1;
   } else if (fs == 32000) {
     fs_index = 2;
   } else if (fs == 48000) {
     fs_index = 3;
   } else {
-    assert(false);
+    RTC_NOTREACHED();
     fs_index = 1;  // Default to 8000 Hz.
   }
 
   if (event < 0 || event > 15) {
     return kParameterError;  // Invalid event number.
   }
 
-  if (attenuation < 0 || attenuation > 36) {
+  if (attenuation < 0 || attenuation > 63) {
     return kParameterError;  // Invalid attenuation.
   }
 
   // Look up oscillator coefficient for low and high frequencies.
+  RTC_DCHECK_LE(0u, fs_index);
+  RTC_DCHECK_GT(arraysize(kCoeff1), fs_index);
+  RTC_DCHECK_GT(arraysize(kCoeff2), fs_index);
+  RTC_DCHECK_LE(0, event);
+  RTC_DCHECK_GT(arraysize(kCoeff1[fs_index]), static_cast<size_t>(event));
+  RTC_DCHECK_GT(arraysize(kCoeff2[fs_index]), static_cast<size_t>(event));
   coeff1_ = kCoeff1[fs_index][event];
   coeff2_ = kCoeff2[fs_index][event];
+
   // Look up amplitude multiplier.
+  RTC_DCHECK_LE(0, attenuation);
+  RTC_DCHECK_GT(arraysize(kAmplitude), static_cast<size_t>(attenuation));
   amplitude_ = kAmplitude[attenuation];
+
   // Initialize sample history.
+  RTC_DCHECK_LE(0u, fs_index);
+  RTC_DCHECK_GT(arraysize(kInitValue1), fs_index);
+  RTC_DCHECK_GT(arraysize(kInitValue2), fs_index);
+  RTC_DCHECK_LE(0, event);
+  RTC_DCHECK_GT(arraysize(kInitValue1[fs_index]), static_cast<size_t>(event));
+  RTC_DCHECK_GT(arraysize(kInitValue2[fs_index]), static_cast<size_t>(event));
   sample_history1_[0] = kInitValue1[fs_index][event];
   sample_history1_[1] = 0;
   sample_history2_[0] = kInitValue2[fs_index][event];
   sample_history2_[1] = 0;
 
   initialized_ = true;
   return 0;
 }
 
 // Reset tone generator to uninitialized state.
@@ skipping 40 matching lines @@
   }
 
   return static_cast<int>(num_samples);
 }
 
 bool DtmfToneGenerator::initialized() const {
   return initialized_;
 }
 
 }  // namespace webrtc