From 3aec97e388e29a1d03f0197b27b893bc6aaf8ac3 Mon Sep 17 00:00:00 2001 From: Jean-Michel Trivi Date: Thu, 29 Aug 2013 12:24:04 -0700 Subject: Encoder downsampled SBR * AAC-Encoder - Introduce optional AACENC_SBR_RATIO encoder API parameter to configure dualrate or downsampled SBR explicitely. ELD makes use of downsampled SBR in default configuration. Modified file(s): documentation\aacEncoder.pdf libAACenc\include\aacenc_lib.h libAACenc\src\aacenc.h libAACenc\src\aacenc_lib.cpp * SBR-Encoder - Implement downsampled SBR feature. - Revise sbr tuning parameter selection. Modified file(s): libSBRenc\include\sbr_encoder.h libSBRenc\src\bit_sbr.h libSBRenc\src\env_est.cpp libSBRenc\src\mh_det.cpp libSBRenc\src\nf_est.cpp libSBRenc\src\ps_main.cpp libSBRenc\src\sbr.h libSBRenc\src\sbr_def.h libSBRenc\src\sbr_encoder.cpp libSBRenc\src\sbr_rom.cpp libSBRenc\src\sbr_rom.h libSBRenc\src\sbrenc_freq_sca.cpp libSBRenc\src\sbrenc_freq_sca.h libSBRenc\src\ton_corr.cpp Bug 9428126 Change-Id: I731720a10829272acaaf70b84525df00a09ff3d2 --- libAACenc/include/aacenc_lib.h | 58 +++++++++++---- libAACenc/src/aacenc.h | 2 + libAACenc/src/aacenc_lib.cpp | 163 +++++++++++++++++++++++++++-------------- 3 files changed, 154 insertions(+), 69 deletions(-) (limited to 'libAACenc') diff --git a/libAACenc/include/aacenc_lib.h b/libAACenc/include/aacenc_lib.h index 649cfba..6002366 100644 --- a/libAACenc/include/aacenc_lib.h +++ b/libAACenc/include/aacenc_lib.h @@ -316,7 +316,8 @@ if the parameter was not set from extern. The bitrate depends on the number of e channels and sampling rate and is determined as follows. \code AAC-LC (AOT_AAC_LC): 1.5 bits per sample -HE-AAC (AOT_SBR): 0.625 bits per sample +HE-AAC (AOT_SBR): 0.625 bits per sample (dualrate sbr) +HE-AAC (AOT_SBR): 1.125 bits per sample (downsampled sbr) HE-AAC v2 (AOT_PS): 0.5 bits per sample \endcode @@ -416,8 +417,9 @@ determines the maximum allowed bitrate for AAC-LC. For HE-AAC and HE-AAC v2 a li look-up table is used. A good working point in terms of audio quality, sampling rate and bitrate, is at 1 to 1.5 -bits/audio sample for AAC-LC, 0.625 bits/audio sample for HE-AAC and 0.5 bits/audio sample -for HE-AAC v2. For example for one channel with a sampling frequency of 48 kHz, the range from +bits/audio sample for AAC-LC, 0.625 bits/audio sample for dualrate HE-AAC, 1.125 bits/audio sample +for downsampled HE-AAC and 0.5 bits/audio sample for HE-AAC v2. +For example for one channel with a sampling frequency of 48 kHz, the range from 48 kbit/s to 72 kbit/s achieves reasonable audio quality for AAC-LC. For HE-AAC and HE-AAC v2 the lowest possible audio input sampling frequency is 16 kHz because then the @@ -434,7 +436,7 @@ quality at that bitrate than HE-AAC or HE-AAC v2. The following table provides an overview of recommended encoder configuration parameters which we determined by virtue of numerous listening tests. -\subsection reommendedConfigLC AAC-LC, HE-AAC, HE-AACv2. +\subsection reommendedConfigLC AAC-LC, HE-AAC, HE-AACv2 in Dualrate SBR mode. \verbatim ----------------------------------------------------------------------------------- Audio Object Type | Bit Rate Range | Supported | Preferred | No. of @@ -457,8 +459,8 @@ AAC LC + SBR | 64000 - 128000 | 32.00, 44.10, 48.00 | 48.00 | -------------------+------------------+-----------------------+------------+------- AAC LC + SBR | 64000 - 69999 | 32.00, 44.10, 48.00 | 32.00 | 5, 5.1 AAC LC + SBR | 70000 - 159999 | 32.00, 44.10, 48.00 | 44.10 | 5, 5.1 -AAC LC + SBR | 160000 - 319999 | 32.00, 44.10, 48.00 | 48.00 | 5, 5.1 -AAC LC + SBR | 320000 - 640000 | 64.00, 88.20, 96.00 | 96.00 | 5, 5.1 +AAC LC + SBR | 160000 - 245999 | 32.00, 44.10, 48.00 | 48.00 | 5 +AAC LC + SBR | 160000 - 265999 | 32.00, 44.10, 48.00 | 48.00 | 5.1 -------------------+------------------+-----------------------+------------+------- AAC LC | 8000 - 15999 | 11.025, 12.00, 16.00 | 12.00 | 1 AAC LC | 16000 - 23999 | 16.00 | 16.00 | 1 @@ -481,7 +483,7 @@ AAC LC | 280000 - 800000 | 32.00, 44.10, 48.00 | 44.10 | 5, ----------------------------------------------------------------------------------- \endverbatim \n -\subsection reommendedConfigLD AAC-LD, AAC-ELD, AAC-ELD with SBR. +\subsection reommendedConfigLD AAC-LD, AAC-ELD, AAC-ELD with SBR in Dualrate SBR mode. \verbatim ----------------------------------------------------------------------------------- Audio Object Type | Bit Rate Range | Supported | Preferred | No. of @@ -489,18 +491,20 @@ Audio Object Type | Bit Rate Range | Supported | Preferred | No. | | [kHz] | Rate | | | | [kHz] | -------------------+------------------+-----------------------+------------+------- -ELD + SBR | 16000 - 24999 | 32.00 - 44.10 | 32.00 | 1 +ELD + SBR | 18000 - 24999 | 32.00 - 44.10 | 32.00 | 1 ELD + SBR | 25000 - 31999 | 32.00 - 48.00 | 32.00 | 1 ELD + SBR | 32000 - 64000 | 32.00 - 48.00 | 48.00 | 1 -------------------+------------------+-----------------------+------------+------- ELD + SBR | 32000 - 51999 | 32.00 - 48.00 | 44.10 | 2 ELD + SBR | 52000 - 128000 | 32.00 - 48.00 | 48.00 | 2 -------------------+------------------+-----------------------+------------+------- -ELD + SBR | 72000 - 192000 | 44.10 - 48.00 | 48.00 | 3 +ELD + SBR | 72000 - 160000 | 44.10 - 48.00 | 48.00 | 3 -------------------+------------------+-----------------------+------------+------- -ELD + SBR | 96000 - 256000 | 44.10 - 48.00 | 48.00 | 4 +ELD + SBR | 96000 - 212000 | 44.10 - 48.00 | 48.00 | 4 -------------------+------------------+-----------------------+------------+------- -ELD + SBR | 120000 - 320000 | 44.10 - 48.00 | 48.00 | 5 +ELD + SBR | 120000 - 246000 | 44.10 - 48.00 | 48.00 | 5 +-------------------+------------------+-----------------------+------------+------- +ELD + SBR | 120000 - 266000 | 44.10 - 48.00 | 48.00 | 5.1 -------------------+------------------+-----------------------+------------+------- LD, ELD | 16000 - 19999 | 16.00 - 24.00 | 16.00 | 1 LD, ELD | 20000 - 39999 | 16.00 - 32.00 | 24.00 | 1 @@ -531,13 +535,33 @@ LD, ELD | 340000 - 960000 | 44.10 - 48.00 | 48.00 | ----------------------------------------------------------------------------------- \endverbatim \n +\subsection reommendedConfigELD AAC-ELD with SBR in Downsampled SBR mode. +\verbatim +----------------------------------------------------------------------------------- +Audio Object Type | Bit Rate Range | Supported | Preferred | No. of + | [bit/s] | Sampling Rates | Sampl. | Chan. + | | [kHz] | Rate | + | | | [kHz] | +-------------------+------------------+-----------------------+------------+------- +ELD + SBR | 18000 - 24999 | 16.00 - 22.05 | 22.05 | 1 +(downsampled SBR) | 25000 - 35999 | 22.05 - 32.00 | 24.00 | 1 + | 36000 - 64000 | 32.00 - 48.00 | 32.00 | 1 +----------------------------------------------------------------------------------- +\endverbatim \n + + \page ENCODERBEHAVIOUR Encoder Behaviour \section BEHAVIOUR_BANDWIDTH Bandwidth The FDK AAC encoder usually does not use the full frequency range of the input signal, but restricts the bandwidth according to certain library-internal settings. They can be changed in the table "bandWidthTable" in the -file bandwidth.cpp (if available), or via command-line argument "-w" (see chapter \ref CommandLineUsage). +file bandwidth.cpp (if available). + +The encoder API provides the ::AACENC_BANDWIDTH parameter to adjust the bandwidth explicitly. +\code +aacEncoder_SetParam(hAacEncoder, AACENC_BANDWIDTH, value); +\endcode However it is not recommended to change these settings, because they are based on numerious listening tests and careful tweaks to ensure the best overall encoding quality. @@ -638,7 +662,6 @@ an MPEG-2 AOT is choosen since PNS is an MPEG-4 AAC feature. If SBR is activated, the encoder automatically deactivates PNS internally. If TNS is disabled but PNS is allowed, the encoder deactivates PNS calculation internally. - */ #ifndef _AAC_ENC_LIB_H_ @@ -875,6 +898,15 @@ typedef enum - 0: MPEG channel ordering (e. g. 5.1: C, L, R, SL, SR, LFE). (default) - 1: WAVE file format channel ordering (e. g. 5.1: L, R, C, LFE, SL, SR). */ + AACENC_SBR_RATIO = 0x0108, /*!< Controls activation of downsampled SBR. With downsampled SBR, the delay will be + shorter. On the other hand, for achieving the same quality level, downsampled SBR + needs more bits than dual-rate SBR. + With downsampled SBR, the AAC encoder will work at the same sampling rate as the + SBR encoder (single rate). + Downsampled SBR is supported for AAC-ELD and HE-AACv1. + - 1: Downsampled SBR (default for ELD). + - 2: Dual-rate SBR (default for HE-AAC). */ + AACENC_AFTERBURNER = 0x0200, /*!< This parameter controls the use of the afterburner feature. The afterburner is a type of analysis by synthesis algorithm which increases the audio quality but also the required processing power. It is recommended to always diff --git a/libAACenc/src/aacenc.h b/libAACenc/src/aacenc.h index c4e1ecb..f07bc17 100644 --- a/libAACenc/src/aacenc.h +++ b/libAACenc/src/aacenc.h @@ -204,6 +204,8 @@ struct AACENC_CONFIG { INT maxBitsPerFrame; /* maximum number of bits in AU */ INT bitreservoir; /* size of bitreservoir */ + UINT sbrRatio; /* sbr sampling rate ratio: dual- or single-rate */ + UCHAR useTns; /* flag: use temporal noise shaping */ UCHAR usePns; /* flag: use perceptual noise substitution */ UCHAR useIS; /* flag: use intensity coding */ diff --git a/libAACenc/src/aacenc_lib.cpp b/libAACenc/src/aacenc_lib.cpp index 4d5984d..0db84e8 100644 --- a/libAACenc/src/aacenc_lib.cpp +++ b/libAACenc/src/aacenc_lib.cpp @@ -98,7 +98,7 @@ amm-info@iis.fraunhofer.de /* Encoder library info */ #define AACENCODER_LIB_VL0 3 #define AACENCODER_LIB_VL1 4 -#define AACENCODER_LIB_VL2 8 +#define AACENCODER_LIB_VL2 9 #define AACENCODER_LIB_TITLE "AAC Encoder" #define AACENCODER_LIB_BUILD_DATE __DATE__ #define AACENCODER_LIB_BUILD_TIME __TIME__ @@ -118,7 +118,7 @@ amm-info@iis.fraunhofer.de #define SBL(fl) (fl/8) /*!< Short block length (hardcoded to 8 short blocks per long block) */ #define BSLA(fl) (4*SBL(fl)+SBL(fl)/2) /*!< AAC block switching look-ahead */ #define DELAY_AAC(fl) (fl+BSLA(fl)) /*!< MDCT + blockswitching */ -#define DELAY_AACELD(fl) ( (fl) + ((fl)/2) ) /*!< ELD FB delay */ +#define DELAY_AACELD(fl) ((fl)/2) /*!< ELD FB delay (no framing delay included) */ #define INPUTBUFFER_SIZE (1537+100+2048) @@ -166,7 +166,8 @@ typedef struct { UCHAR userMetaDataMode; /*!< Meta data library configuration. */ - UCHAR userSbrEnabled; + UCHAR userSbrEnabled; /*!< Enable SBR for ELD. */ + UINT userSbrRatio; /*!< SBR sampling rate ratio. Dual- or single-rate. */ } USER_PARAM; @@ -229,7 +230,7 @@ struct AACENCODER UINT encoder_modis; - /* Capabity flags */ + /* Capability flags */ UINT CAPF_tpEnc; } ; @@ -255,6 +256,20 @@ static inline INT isSbrActive(const HANDLE_AACENC_CONFIG hAacConfig) return ( sbrUsed ); } +static inline INT isPsActive(const AUDIO_OBJECT_TYPE audioObjectType) +{ + INT psUsed = 0; + + if ( (audioObjectType==AOT_PS) + || (audioObjectType==AOT_MP2_PS) + || (audioObjectType==AOT_DABPLUS_PS) + || (audioObjectType==AOT_DRM_MPEG_PS) ) + { + psUsed = 1; + } + + return ( psUsed ); +} /**************************************************************************** Allocate Encoder ****************************************************************************/ @@ -449,6 +464,14 @@ AAC_ENCODER_ERROR aacEncDefaultConfig(HANDLE_AACENC_CONFIG hAacConfig, config->userAncDataRate = 0; + /* SBR rate is set to 0 here, which means it should be set automatically + in FDKaacEnc_AdjustEncSettings() if the user did not set a rate + expilicitely. */ + config->userSbrRatio = 0; + + /* SBR enable set to -1 means to inquire ELD audio configurator for reasonable configuration. */ + config->userSbrEnabled = -1; + return AAC_ENC_OK; } @@ -483,6 +506,7 @@ INT aacEncoder_LimitBitrate( INT bitRate, const INT nSubFrames, const INT sbrActive, + const INT sbrDownSampleRate, const AUDIO_OBJECT_TYPE aot ) { @@ -492,8 +516,7 @@ INT aacEncoder_LimitBitrate( FDKaacEnc_InitChannelMapping(channelMode, CH_ORDER_MPEG, &cm); if (sbrActive) { - /* Assume SBR rate ratio of 2:1 */ - coreSamplingRate = samplingRate / 2; + coreSamplingRate = samplingRate >> (sbrEncoder_IsSingleRatePossible(aot) ? (sbrDownSampleRate-1):1); } else { coreSamplingRate = samplingRate; } @@ -669,19 +692,6 @@ AACENC_ERROR FDKaacEnc_AdjustEncSettings(HANDLE_AACENCODER hAacEncoder, break; } - /* We need the frame length to call aacEncoder_LimitBitrate() */ - hAacConfig->bitRate = aacEncoder_LimitBitrate( - NULL, - hAacConfig->sampleRate, - hAacConfig->framelength, - hAacConfig->nChannels, - hAacConfig->channelMode, - config->userBitrate, - hAacConfig->nSubFrames, - isSbrActive(hAacConfig), - hAacConfig->audioObjectType - ); - switch ( hAacConfig->audioObjectType ) { case AOT_ER_AAC_LD: case AOT_ER_AAC_ELD: @@ -699,24 +709,7 @@ AACENC_ERROR FDKaacEnc_AdjustEncSettings(HANDLE_AACENCODER hAacEncoder, break; } - if (hAacConfig->epConfig >= 0) { - hAacConfig->syntaxFlags |= AC_ER; - if (((INT)hAacConfig->channelMode < 1) || ((INT)hAacConfig->channelMode > 7)) { - return AACENC_INVALID_CONFIG; /* Cannel config 0 not supported. */ - } - } - - if ( FDKaacEnc_DetermineEncoderMode(&hAacConfig->channelMode, hAacConfig->nChannels) != AAC_ENC_OK) { - return AACENC_INVALID_CONFIG; /* nChannels doesn't match chMode, this is just a check-up */ - } - - if ( (hAacConfig->nChannels > hAacEncoder->nMaxAacChannels) - || ( (FDKaacEnc_GetChannelModeConfiguration(hAacConfig->channelMode)->nChannelsEff > hAacEncoder->nMaxSbrChannels) && - isSbrActive(hAacConfig) ) - ) - { - return AACENC_INVALID_CONFIG; /* not enough channels allocated */ - } + hAacConfig->bitRate = config->userBitrate; /* get bitrate in VBR configuration */ if ( (hAacConfig->bitrateMode>=1) && (hAacConfig->bitrateMode<=5) ) { @@ -727,25 +720,52 @@ AACENC_ERROR FDKaacEnc_AdjustEncSettings(HANDLE_AACENCODER hAacEncoder, /* Set default bitrate if no external bitrate declared. */ - if (hAacConfig->bitRate==-1) { + if ( (hAacConfig->bitrateMode==0) && (config->userBitrate==(UINT)-1) ) { INT bitrate = FDKaacEnc_GetChannelModeConfiguration(hAacConfig->channelMode)->nChannelsEff * hAacConfig->sampleRate; - switch (hAacConfig->audioObjectType) + + if ( isPsActive(hAacConfig->audioObjectType) ) { + hAacConfig->bitRate = (bitrate>>1); /* 0.5 bit per sample */ + } + else if ( isSbrActive(hAacConfig) ) + { + if ( (config->userSbrRatio==2) || ((config->userSbrRatio==0)&&(hAacConfig->audioObjectType!=AOT_ER_AAC_ELD)) ) { + hAacConfig->bitRate = (bitrate + (bitrate>>2))>>1; /* 0.625 bits per sample */ + } + if ( (config->userSbrRatio==1) || ((config->userSbrRatio==0)&&(hAacConfig->audioObjectType==AOT_ER_AAC_ELD)) ) { + hAacConfig->bitRate = (bitrate + (bitrate>>3)); /* 1.125 bits per sample */ + } + } else { - case AOT_AAC_LC: hAacConfig->bitRate = bitrate + (bitrate>>1); /* 1.5 bits per sample */ - break; - case AOT_SBR: - hAacConfig->bitRate = (bitrate + (bitrate>>2))>>1; /* 0.625 bits per sample */ - break; - case AOT_PS: - hAacConfig->bitRate = (bitrate>>1); /* 0.5 bit per sample */ - break; - default: - hAacConfig->bitRate = bitrate; - break; } } + /* Initialize SBR parameters */ + if ( (config->userSbrRatio==0) && (isSbrActive(hAacConfig)) ) { + /* Automatic SBR ratio configuration + * - downsampled SBR for ELD + * - otherwise always dualrate SBR + */ + hAacConfig->sbrRatio = (hAacConfig->audioObjectType==AOT_ER_AAC_ELD) ? 1 : 2; + } + else { + /* SBR ratio has been set by the user, so use it. */ + hAacConfig->sbrRatio = config->userSbrRatio; + } + /* We need the frame length to call aacEncoder_LimitBitrate() */ + hAacConfig->bitRate = aacEncoder_LimitBitrate( + NULL, + hAacConfig->sampleRate, + hAacConfig->framelength, + hAacConfig->nChannels, + hAacConfig->channelMode, + hAacConfig->bitRate, + hAacConfig->nSubFrames, + isSbrActive(hAacConfig), + hAacConfig->sbrRatio, + hAacConfig->audioObjectType + ); + /* Configure PNS */ if ( ((hAacConfig->bitrateMode>=1) && (hAacConfig->bitrateMode<=5)) /* VBR without PNS. */ || (hAacConfig->useTns == 0) ) /* TNS required. */ @@ -753,6 +773,25 @@ AACENC_ERROR FDKaacEnc_AdjustEncSettings(HANDLE_AACENCODER hAacEncoder, hAacConfig->usePns = 0; } + if (hAacConfig->epConfig >= 0) { + hAacConfig->syntaxFlags |= AC_ER; + if (((INT)hAacConfig->channelMode < 1) || ((INT)hAacConfig->channelMode > 7)) { + return AACENC_INVALID_CONFIG; /* Cannel config 0 not supported. */ + } + } + + if ( FDKaacEnc_DetermineEncoderMode(&hAacConfig->channelMode, hAacConfig->nChannels) != AAC_ENC_OK) { + return AACENC_INVALID_CONFIG; /* nChannels doesn't match chMode, this is just a check-up */ + } + + if ( (hAacConfig->nChannels > hAacEncoder->nMaxAacChannels) + || ( (FDKaacEnc_GetChannelModeConfiguration(hAacConfig->channelMode)->nChannelsEff > hAacEncoder->nMaxSbrChannels) && + isSbrActive(hAacConfig) ) + ) + { + return AACENC_INVALID_CONFIG; /* not enough channels allocated */ + } + /* Meta data restriction. */ switch (hAacConfig->audioObjectType) { @@ -846,8 +885,6 @@ static AACENC_ERROR aacEncInit(HANDLE_AACENCODER hAacEncoder, SBR_ELEMENT_INFO sbrElInfo[(6)]; CHANNEL_MAPPING channelMapping; - AUDIO_OBJECT_TYPE aot = hAacConfig->audioObjectType; - if ( FDKaacEnc_InitChannelMapping(hAacConfig->channelMode, hAacConfig->channelOrder, &channelMapping) != AAC_ENC_OK ) @@ -875,8 +912,9 @@ static AACENC_ERROR aacEncInit(HANDLE_AACENCODER hAacEncoder, &aacBufferOffset, &hAacConfig->nChannels, &hAacConfig->sampleRate, + &hAacConfig->sbrRatio, &frameLength, - &hAacConfig->audioObjectType, + hAacConfig->audioObjectType, &hAacEncoder->nDelay, (hAacConfig->audioObjectType == AOT_ER_AAC_ELD) ? 1 : TRANS_FAC, (config->userTpHeaderPeriod!=0xFF) ? config->userTpHeaderPeriod : DEFAULT_HEADER_PERIOD_REPETITION_RATE, @@ -884,7 +922,7 @@ static AACENC_ERROR aacEncInit(HANDLE_AACENCODER hAacEncoder, ); /* Suppress AOT reconfiguration and check error status. */ - if ( sbrError || (hAacConfig->audioObjectType!=aot) ) { + if (sbrError) { return AACENC_INIT_SBR_ERROR; } @@ -953,7 +991,7 @@ static AACENC_ERROR aacEncInit(HANDLE_AACENCODER hAacEncoder, INT inputDataDelay = DELAY_AAC(hAacConfig->framelength); if ( isSbrActive(hAacConfig) && hSbrEncoder!=NULL) { - inputDataDelay = 2*inputDataDelay + sbrEncoder_GetInputDataDelay(*hSbrEncoder); + inputDataDelay = hAacConfig->sbrRatio*inputDataDelay + sbrEncoder_GetInputDataDelay(*hSbrEncoder); } if ( FDK_MetadataEnc_Init(hAacEncoder->hMetadataEnc, @@ -1684,6 +1722,16 @@ AACENC_ERROR aacEncoder_SetParam( } } break; + case AACENC_SBR_RATIO: + if (settings->userSbrRatio != value) { + if (! ((value==0) || (value==1) || (value==2)) ) { + err = AACENC_INVALID_CONFIG; + break; + } + settings->userSbrRatio = value; + hAacEncoder->InitFlags |= AACENC_INIT_CONFIG | AACENC_INIT_STATES | AACENC_INIT_TRANSPORT; + } + break; case AACENC_SBR_MODE: if (settings->userSbrEnabled != value) { settings->userSbrEnabled = value; @@ -1805,7 +1853,7 @@ UINT aacEncoder_GetParam( value = (UINT)hAacEncoder->aacConfig.bitrateMode; break; case AACENC_SAMPLERATE: - value = (UINT)settings->userSamplerate; + value = (UINT)hAacEncoder->coderConfig.extSamplingRate; break; case AACENC_CHANNELMODE: value = (UINT)hAacEncoder->aacConfig.channelMode; @@ -1822,6 +1870,9 @@ UINT aacEncoder_GetParam( case AACENC_GRANULE_LENGTH: value = (UINT)hAacEncoder->aacConfig.framelength; break; + case AACENC_SBR_RATIO: + value = isSbrActive(&hAacEncoder->aacConfig) ? hAacEncoder->aacConfig.sbrRatio : 0; + break; case AACENC_SBR_MODE: value = (UINT) (hAacEncoder->aacConfig.syntaxFlags & AC_SBR_PRESENT) ? 1 : 0; break; -- cgit v1.2.3