summaryrefslogtreecommitdiffstats
path: root/libAACdec/src/aacdec_drc.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'libAACdec/src/aacdec_drc.cpp')
-rw-r--r--libAACdec/src/aacdec_drc.cpp38
1 files changed, 26 insertions, 12 deletions
diff --git a/libAACdec/src/aacdec_drc.cpp b/libAACdec/src/aacdec_drc.cpp
index c660b83..ebc6975 100644
--- a/libAACdec/src/aacdec_drc.cpp
+++ b/libAACdec/src/aacdec_drc.cpp
@@ -220,8 +220,9 @@ AAC_DECODER_ERROR aacDecoder_drcSetParam (
else {
/* ref_level must be between 0 and MAX_REFERENCE_LEVEL, inclusive */
self->digitalNorm = 1;
- self->progRefLevel = AACDEC_DRC_DEFAULT_REF_LEVEL;
self->params.targetRefLevel = value;
+ self->progRefLevel = (SCHAR)value; /* Set the program reference level equal to the target
+ level according to 4.5.2.7.3 of ISO/IEC 14496-3. */
}
break;
case APPLY_HEAVY_COMPRESSION:
@@ -783,6 +784,7 @@ void aacDecoder_drcApply (
{
int band, top, bin, numBands;
int bottom = 0;
+ int modifyBins = 0;
FIXP_DBL max_mantissa;
INT max_exponent;
@@ -937,6 +939,12 @@ void aacDecoder_drcApply (
if (fact_exponent[band] < max_exponent) {
fact_mantissa[band] >>= max_exponent - fact_exponent[band];
}
+ if (fact_mantissa[band] != FL2FXCONST_DBL(0.5f)) {
+ modifyBins = 1;
+ }
+ }
+ if (max_exponent != 1) {
+ modifyBins = 1;
}
}
@@ -948,23 +956,28 @@ void aacDecoder_drcApply (
{
bottom = 0;
- for (band = 0; band < numBands; band++)
+ if (!modifyBins) {
+ /* We don't have to modify the spectral bins because the fractional part of all factors is 0.5.
+ In order to keep accurancy we don't apply the factor but decrease the exponent instead. */
+ max_exponent -= 1;
+ } else
{
- top = fixMin((int)( (pDrcChData->bandTop[band]+1)<<2 ), aacFrameSize); /* ... * DRC_BAND_MULT; */
+ for (band = 0; band < numBands; band++)
+ {
+ top = fixMin((int)( (pDrcChData->bandTop[band]+1)<<2 ), aacFrameSize); /* ... * DRC_BAND_MULT; */
- for (bin = bottom; bin < top; bin++) {
- pSpectralCoefficient[bin] = fMult(pSpectralCoefficient[bin], fact_mantissa[band]);
- }
+ for (bin = bottom; bin < top; bin++) {
+ pSpectralCoefficient[bin] = fMult(pSpectralCoefficient[bin], fact_mantissa[band]);
+ }
- bottom = top;
+ bottom = top;
+ }
}
/* above topmost DRC band gain factor is 1 */
if (max_exponent > 0) {
- FIXP_DBL fact = FL2FXCONST_DBL(0.5f) >> (max_exponent - 1);
-
- for (bin = top; bin < aacFrameSize; bin++) {
- pSpectralCoefficient[bin] = fMult(pSpectralCoefficient[bin], fact);
+ for (bin = bottom; bin < aacFrameSize; bin+=1) {
+ pSpectralCoefficient[bin] >>= max_exponent;
}
}
@@ -980,12 +993,13 @@ void aacDecoder_drcApply (
}
else {
HANDLE_SBRDECODER hSbrDecoder = (HANDLE_SBRDECODER)pSbrDec;
+ UINT numBands = pDrcChData->numBands;
/* feed factors into SBR decoder for application in QMF domain. */
sbrDecoder_drcFeedChannel (
hSbrDecoder,
ch,
- pDrcChData->numBands,
+ numBands,
fact_mantissa,
max_exponent,
pDrcChData->drcInterpolationScheme,