Delete full-band mode from the iSAC codec

webrtc/modules/audio_coding/codecs/isac/main/source/isac.c

Index: webrtc/modules/audio_coding/codecs/isac/main/source/isac.c
diff --git a/webrtc/modules/audio_coding/codecs/isac/main/source/isac.c b/webrtc/modules/audio_coding/codecs/isac/main/source/isac.c
index 0a5f75a901635b6be23e03ae2aad5489091c5555..bc1565151be231c0569ae7bb8804af27ef8a28c0 100644
--- a/webrtc/modules/audio_coding/codecs/isac/main/source/isac.c
+++ b/webrtc/modules/audio_coding/codecs/isac/main/source/isac.c
@@ -469,7 +469,6 @@ int16_t WebRtcIsac_EncoderInit(ISACStruct* ISAC_main_inst,
       return -1;
     }
   }
-  memset(instISAC->state_in_resampler, 0, sizeof(instISAC->state_in_resampler));
   /* Initialization is successful, set the flag. */
   instISAC->initFlag |= BIT_MASK_ENC_INIT;
   return 0;
@@ -516,8 +515,6 @@ int WebRtcIsac_Encode(ISACStruct* ISAC_main_inst,
   ISACMainStruct* instISAC = (ISACMainStruct*)ISAC_main_inst;
   ISACLBStruct* instLB = &(instISAC->instLB);
   ISACUBStruct* instUB = &(instISAC->instUB);
-  const int16_t* speech_in_ptr = speechIn;
-  int16_t resampled_buff[FRAMESAMPLES_10ms * 2];
 
   /* Check if encoder initiated. */
   if ((instISAC->initFlag & BIT_MASK_ENC_INIT) !=
@@ -526,37 +523,8 @@ int WebRtcIsac_Encode(ISACStruct* ISAC_main_inst,
     return -1;
   }
 
-  if (instISAC->in_sample_rate_hz == 48000) {
-    /* Samples in 10 ms @ 48 kHz. */
-    const size_t kNumInputSamples = FRAMESAMPLES_10ms * 3;
-    /* Samples 10 ms @ 32 kHz. */
-    const size_t kNumOutputSamples = FRAMESAMPLES_10ms * 2;
-    /* Resampler divide the input into blocks of 3 samples, i.e.
-     * kNumInputSamples / 3. */
-    const size_t kNumResamplerBlocks = FRAMESAMPLES_10ms;
-    int32_t buffer32[FRAMESAMPLES_10ms * 3 + SIZE_RESAMPLER_STATE];
-
-    /* Restore last samples from the past to the beginning of the buffer
-     * and store the last samples of current frame for the next resampling. */
-    for (k = 0; k < SIZE_RESAMPLER_STATE; k++) {
-      buffer32[k] = instISAC->state_in_resampler[k];
-      instISAC->state_in_resampler[k] = speechIn[kNumInputSamples -
-                                                 SIZE_RESAMPLER_STATE + k];
-    }
-    for (k = 0; k < kNumInputSamples; k++) {
-      buffer32[SIZE_RESAMPLER_STATE + k] = speechIn[k];
-    }
-    /* Resampling 3 samples to 2. Function divides the input in
-     * |kNumResamplerBlocks| number of 3-sample groups, and output is
-     * |kNumResamplerBlocks| number of 2-sample groups. */
-    WebRtcSpl_Resample48khzTo32khz(buffer32, buffer32, kNumResamplerBlocks);
-    WebRtcSpl_VectorBitShiftW32ToW16(resampled_buff, kNumOutputSamples,
-                                     buffer32, 15);
-    speech_in_ptr = resampled_buff;
-  }
-
   if (instISAC->encoderSamplingRateKHz == kIsacSuperWideband) {
-    WebRtcSpl_AnalysisQMF(speech_in_ptr, SWBFRAMESAMPLES_10ms, speechInLB,
+    WebRtcSpl_AnalysisQMF(speechIn, SWBFRAMESAMPLES_10ms, speechInLB,
                           speechInUB, instISAC->analysisFBState1,
                           instISAC->analysisFBState2);
 
@@ -1852,10 +1820,8 @@ int16_t WebRtcIsac_GetNewFrameLen(ISACStruct* ISAC_main_inst) {
   /* Return new frame length. */
   if (instISAC->in_sample_rate_hz == 16000)
     return (instISAC->instLB.ISACencLB_obj.new_framelength);
-  else if (instISAC->in_sample_rate_hz == 32000)
+  else  /* 32000 Hz */
     return ((instISAC->instLB.ISACencLB_obj.new_framelength) * 2);
-  else
-    return ((instISAC->instLB.ISACencLB_obj.new_framelength) * 3);
 }
 
 
@@ -2205,17 +2171,10 @@ void WebRtcIsac_version(char* version) {
  * and the bottleneck remain unchanged by this call, however, the maximum rate
  * and maximum payload-size will be reset to their default values.
  *
- * NOTE:
- * The maximum internal sampling rate is 32 kHz. If the encoder sample rate is
- * set to 48 kHz the input is expected to be at 48 kHz but will be resampled to
- * 32 kHz before any further processing.
- * This mode is created for compatibility with full-band codecs if iSAC is used
- * in dual-streaming. See SetDecSampleRate() for sampling rates at the decoder.
- *
  * Input:
  *        - ISAC_main_inst    : iSAC instance
- *        - sample_rate_hz    : sampling rate in Hertz, valid values are 16000,
- *                              32000 and 48000.
+ *        - sample_rate_hz    : sampling rate in Hertz, valid values are 16000
+ *                              and 32000.
  *
  * Return value               : 0 if successful
  *                             -1 if failed.
@@ -2225,8 +2184,7 @@ int16_t WebRtcIsac_SetEncSampRate(ISACStruct* ISAC_main_inst,
   ISACMainStruct* instISAC = (ISACMainStruct*)ISAC_main_inst;
   enum IsacSamplingRate encoder_operational_rate;
 
-  if ((sample_rate_hz != 16000) && (sample_rate_hz != 32000) &&
-      (sample_rate_hz != 48000)) {
+  if ((sample_rate_hz != 16000) && (sample_rate_hz != 32000)) {
     /* Sampling Frequency is not supported. */
     instISAC->errorCode = ISAC_UNSUPPORTED_SAMPLING_FREQUENCY;
     return -1;