Avoid -1.0 autocorrelation input data.

am: e51063ca54

Change-Id: Ic059b05ceb43d993900805c746382d17adc52ee8
This commit is contained in:
Fraunhofer IIS FDK 2019-05-15 22:54:08 -07:00 committed by android-build-merger
commit ced1a601f0
1 changed files with 21 additions and 3 deletions

View File

@ -1,7 +1,7 @@
/* -----------------------------------------------------------------------------
Software License for The Fraunhofer FDK AAC Codec Library for Android
© Copyright 1995 - 2018 Fraunhofer-Gesellschaft zur Förderung der angewandten
© Copyright 1995 - 2019 Fraunhofer-Gesellschaft zur Förderung der angewandten
Forschung e.V. All rights reserved.
1. INTRODUCTION
@ -446,8 +446,26 @@ void lppTransposer(
pSettings->nCols) +
lowBandShift);
}
dynamicScale = fixMax(
0, dynamicScale - 1); /* one additional bit headroom to prevent -1.0 */
if (dynamicScale == 0) {
/* In this special case the available headroom bits as well as
ovLowBandShift and lowBandShift are zero. The spectrum is limited to
prevent -1.0, so negative values for dynamicScale can be avoided. */
for (i = 0; i < (LPC_ORDER + pSettings->overlap + pSettings->nCols);
i++) {
lowBandReal[i] = fixMax(lowBandReal[i], (FIXP_DBL)0x80000001);
}
if (!useLP) {
for (i = 0; i < (LPC_ORDER + pSettings->overlap + pSettings->nCols);
i++) {
lowBandImag[i] = fixMax(lowBandImag[i], (FIXP_DBL)0x80000001);
}
}
} else {
dynamicScale =
fixMax(0, dynamicScale -
1); /* one additional bit headroom to prevent -1.0 */
}
/*
Scale temporal QMF buffer.