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Diffstat (limited to '')
-rw-r--r-- | third_party/libwebrtc/modules/audio_coding/codecs/ilbc/comp_corr.c | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/third_party/libwebrtc/modules/audio_coding/codecs/ilbc/comp_corr.c b/third_party/libwebrtc/modules/audio_coding/codecs/ilbc/comp_corr.c new file mode 100644 index 0000000000..452bc78e3b --- /dev/null +++ b/third_party/libwebrtc/modules/audio_coding/codecs/ilbc/comp_corr.c @@ -0,0 +1,51 @@ +/* + * 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_CompCorr.c + +******************************************************************/ + +#include "modules/audio_coding/codecs/ilbc/comp_corr.h" + +#include "modules/audio_coding/codecs/ilbc/defines.h" + +/*----------------------------------------------------------------* + * Compute cross correlation and pitch gain for pitch prediction + * of last subframe at given lag. + *---------------------------------------------------------------*/ + +void WebRtcIlbcfix_CompCorr( + int32_t *corr, /* (o) cross correlation */ + int32_t *ener, /* (o) energy */ + int16_t *buffer, /* (i) signal buffer */ + size_t lag, /* (i) pitch lag */ + size_t bLen, /* (i) length of buffer */ + size_t sRange, /* (i) correlation search length */ + int16_t scale /* (i) number of rightshifts to use */ + ){ + int16_t *w16ptr; + + w16ptr=&buffer[bLen-sRange-lag]; + + /* Calculate correlation and energy */ + (*corr)=WebRtcSpl_DotProductWithScale(&buffer[bLen-sRange], w16ptr, sRange, scale); + (*ener)=WebRtcSpl_DotProductWithScale(w16ptr, w16ptr, sRange, scale); + + /* For zero energy set the energy to 0 in order to avoid potential + problems for coming divisions */ + if (*ener == 0) { + *corr = 0; + *ener = 1; + } +} |