diff options
Diffstat (limited to 'fdk-aac/libAACenc/src/aacenc.cpp')
| -rw-r--r-- | fdk-aac/libAACenc/src/aacenc.cpp | 53 |
1 files changed, 47 insertions, 6 deletions
diff --git a/fdk-aac/libAACenc/src/aacenc.cpp b/fdk-aac/libAACenc/src/aacenc.cpp index 372df31..42755ab 100644 --- a/fdk-aac/libAACenc/src/aacenc.cpp +++ b/fdk-aac/libAACenc/src/aacenc.cpp @@ -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 - 2020 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. All rights reserved. 1. INTRODUCTION @@ -114,6 +114,8 @@ amm-info@iis.fraunhofer.de #include "genericStds.h" +#define BITRES_MIN \ + 300 /* default threshold for using reduced/disabled bitres mode */ #define BITRES_MAX_LD 4000 #define BITRES_MIN_LD 500 #define BITRATE_MAX_LD 70000 /* Max assumed bitrate for bitres calculation */ @@ -244,6 +246,46 @@ INT FDKaacEnc_GetVBRBitrate(AACENC_BITRATE_MODE bitrateMode, return bitrate; } +/*----------------------------------------------------------------------------- + + functionname: FDKaacEnc_AdjustVBRBitrateMode + description: Adjust bitrate mode to given bitrate parameter + input params: int vbrQuality (VBR0, VBR1, VBR2) + bitrate + channelMode + returns: vbr bitrate mode + + ------------------------------------------------------------------------------*/ +AACENC_BITRATE_MODE FDKaacEnc_AdjustVBRBitrateMode( + AACENC_BITRATE_MODE bitrateMode, INT bitrate, CHANNEL_MODE channelMode) { + AACENC_BITRATE_MODE newBitrateMode = bitrateMode; + + if (bitrate != -1) { + const INT monoStereoMode = + (FDKaacEnc_GetMonoStereoMode(channelMode) == EL_MODE_STEREO) ? 1 : 0; + const INT nChannelsEff = + FDKaacEnc_GetChannelModeConfiguration(channelMode)->nChannelsEff; + newBitrateMode = AACENC_BR_MODE_INVALID; + + for (int idx = (int)(sizeof(configTabVBR) / sizeof(*configTabVBR)) - 1; + idx >= 0; idx--) { + if (bitrate >= + configTabVBR[idx].chanBitrate[monoStereoMode] * nChannelsEff) { + if (configTabVBR[idx].chanBitrate[monoStereoMode] * nChannelsEff < + FDKaacEnc_GetVBRBitrate(bitrateMode, channelMode)) { + newBitrateMode = configTabVBR[idx].bitrateMode; + } else { + newBitrateMode = bitrateMode; + } + break; + } + } + } + + return AACENC_BR_MODE_IS_VBR(newBitrateMode) ? newBitrateMode + : AACENC_BR_MODE_INVALID; +} + /** * \brief Convert encoder bitreservoir value for transport library. * @@ -396,7 +438,6 @@ AAC_ENCODER_ERROR FDKaacEnc_Initialize( FIXP_DBL mbfac, bw_ratio; QC_INIT qcInit; INT averageBitsPerFrame = 0; - int bitresMin = 0; /* the bitreservoir is always big for AAC-LC */ const CHANNEL_MODE prevChannelMode = hAacEnc->encoderMode; if (config == NULL) return AAC_ENC_INVALID_HANDLE; @@ -582,7 +623,7 @@ AAC_ENCODER_ERROR FDKaacEnc_Initialize( (config->minBitsPerFrame != -1) ? config->minBitsPerFrame : 0; qcInit.minBits = fixMin(qcInit.minBits, averageBitsPerFrame & ~7); } else { - INT bitreservoir = -1; /* default bitrservoir size*/ + INT bitreservoir = -1; /* default bitreservoir size*/ if (isLowDelay(config->audioObjectType)) { INT brPerChannel = config->bitRate / config->nChannels; brPerChannel = fMin(BITRATE_MAX_LD, fMax(BITRATE_MIN_LD, brPerChannel)); @@ -596,7 +637,6 @@ AAC_ENCODER_ERROR FDKaacEnc_Initialize( bitreservoir = fMultI(slope, (INT)(BITRES_MAX_LD - BITRES_MIN_LD)) + BITRES_MIN_LD; /* interpolate */ bitreservoir = bitreservoir & ~7; /* align to bytes */ - bitresMin = BITRES_MIN_LD; } int maxBitres; @@ -633,9 +673,10 @@ AAC_ENCODER_ERROR FDKaacEnc_Initialize( qcInit.nSubFrames = config->nSubFrames; qcInit.padding.paddingRest = config->sampleRate; - if (qcInit.bitRes >= bitresMin * config->nChannels) { + if (qcInit.maxBits - qcInit.averageBits >= + ((qcInit.isLowDelay) ? BITRES_MIN_LD : BITRES_MIN) * config->nChannels) { qcInit.bitResMode = AACENC_BR_MODE_FULL; /* full bitreservoir */ - } else if (qcInit.bitRes > 0) { + } else if (qcInit.maxBits > qcInit.averageBits) { qcInit.bitResMode = AACENC_BR_MODE_REDUCED; /* reduced bitreservoir */ } else { qcInit.bitResMode = AACENC_BR_MODE_DISABLED; /* disabled bitreservoir */ |