diff options
Diffstat (limited to 'third_party/libwebrtc/modules/audio_coding/codecs/ilbc/abs_quant.c')
-rw-r--r-- | third_party/libwebrtc/modules/audio_coding/codecs/ilbc/abs_quant.c | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/third_party/libwebrtc/modules/audio_coding/codecs/ilbc/abs_quant.c b/third_party/libwebrtc/modules/audio_coding/codecs/ilbc/abs_quant.c new file mode 100644 index 0000000000..77da78ba7f --- /dev/null +++ b/third_party/libwebrtc/modules/audio_coding/codecs/ilbc/abs_quant.c @@ -0,0 +1,82 @@ +/* + * Copyright (c) 2011 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. + */ + +/****************************************************************** + + iLBC Speech Coder ANSI-C Source Code + + WebRtcIlbcfix_AbsQuant.c + +******************************************************************/ + +#include "modules/audio_coding/codecs/ilbc/abs_quant.h" + +#include "modules/audio_coding/codecs/ilbc/abs_quant_loop.h" +#include "modules/audio_coding/codecs/ilbc/constants.h" +#include "modules/audio_coding/codecs/ilbc/defines.h" + + +/*----------------------------------------------------------------* + * predictive noise shaping encoding of scaled start state + * (subrutine for WebRtcIlbcfix_StateSearch) + *---------------------------------------------------------------*/ + +void WebRtcIlbcfix_AbsQuant( + IlbcEncoder *iLBCenc_inst, + /* (i) Encoder instance */ + iLBC_bits *iLBC_encbits, /* (i/o) Encoded bits (outputs idxForMax + and idxVec, uses state_first as + input) */ + int16_t *in, /* (i) vector to encode */ + int16_t *weightDenum /* (i) denominator of synthesis filter */ + ) { + int16_t *syntOut; + size_t quantLen[2]; + + /* Stack based */ + int16_t syntOutBuf[LPC_FILTERORDER+STATE_SHORT_LEN_30MS]; + int16_t in_weightedVec[STATE_SHORT_LEN_30MS+LPC_FILTERORDER]; + int16_t *in_weighted = &in_weightedVec[LPC_FILTERORDER]; + + /* Initialize the buffers */ + WebRtcSpl_MemSetW16(syntOutBuf, 0, LPC_FILTERORDER+STATE_SHORT_LEN_30MS); + syntOut = &syntOutBuf[LPC_FILTERORDER]; + /* Start with zero state */ + WebRtcSpl_MemSetW16(in_weightedVec, 0, LPC_FILTERORDER); + + /* Perform the quantization loop in two sections of length quantLen[i], + where the perceptual weighting filter is updated at the subframe + border */ + + if (iLBC_encbits->state_first) { + quantLen[0]=SUBL; + quantLen[1]=iLBCenc_inst->state_short_len-SUBL; + } else { + quantLen[0]=iLBCenc_inst->state_short_len-SUBL; + quantLen[1]=SUBL; + } + + /* Calculate the weighted residual, switch perceptual weighting + filter at the subframe border */ + WebRtcSpl_FilterARFastQ12( + in, in_weighted, + weightDenum, LPC_FILTERORDER+1, quantLen[0]); + WebRtcSpl_FilterARFastQ12( + &in[quantLen[0]], &in_weighted[quantLen[0]], + &weightDenum[LPC_FILTERORDER+1], LPC_FILTERORDER+1, quantLen[1]); + + WebRtcIlbcfix_AbsQuantLoop( + syntOut, + in_weighted, + weightDenum, + quantLen, + iLBC_encbits->idxVec); + +} |