1、 INTERNATIONAL STANDARD ISO/IEC 23003-3:2012 TECHNICAL CORRIGENDUM 2 Published 2013-09-01 INTERNATIONAL ORGANIZATION FOR STANDARDIZATION ORGANISATION INTERNATIONALE DE NORMALISATION INTERNATIONAL ELECTROTECHNICAL COMMISSION COMMISSION LECTROTECHNIQUE INTERNATIONALEInformation technology MPEG audio t
2、echnologies Part 3: Unified speech and audio coding TECHNICAL CORRIGENDUM 2 Technologies de linformation Technologies audio MPEG Partie 3: Discours unifi et codage audio RECTIFICATIF TECHNIQUE 2 Technical Corrigendum 2 to ISO/IEC 23003-3:2012 was prepared by Joint Technical Committee ISO/IEC JTC 1,
3、Information technology, Subcommittee SC 29, Coding of audio, picture, multimedia and hypermedia information. At the end of 4.5.3 add: “ Furthermore, restrictions on the sampling rate apply for the USAC Baseline profile. The sampling rate signaled as part of the UsacConfig() shall be one out of those
4、 listed in Table 3. These sampling rates are chosen such that they can conveniently be resampled to 44100 Hz and 48000 Hz, respectively. ICS 35.040 Ref. No. ISO/IEC 23003-3:2012/Cor.2:2013(E) ISO/IEC 2013 All rights reserved Published in Switzerland ISO/IEC 23003-3:2012/Cor.2:2013(E) 2 ISO/IEC 2013
5、All rights reservedTable 3 Allowed sampling rates for the Baseline USAC profile SamplingRates Hz and usacSamplingFrequencyIndex 88200 0x01 96000 0x00 70560 n/a 76800 n/a 58800 n/a 64000 0x02 44100 0x04 48000 0x03 35280 n/a 38400 0x12 29400 n/a 32000 0x05 22050 0x07 24000 0x06 17640 n/a 19200 0x17 14
6、700 n/a 16000 0x08 11760 n/a 12800 0x1a 11025 0x0a 12000 0x09 8820 n/a 9600 0x1b 7350 0x0c 8000 0x0b “ In 5.3.2 replace: “ Table 23 Syntax of UsacCoreCoderData() Syntax No. of bits Mnemonic UsacCoreCoderData(nrChannels, indepFlag) for (ch=0; ch nrChannels; ch+) core_modech; 1 uimsbf if (nrChannels =
7、 2) StereoCoreToolInfo(core_mode); for (ch=0; chnrChannels; ch+) if (core_modech = 1) lpd_channel_stream(indepFlag); e l s e if ( (nrChannels = 1) | (core_mode0 != core_mode1) ) tns_data_presentch; 1 uimsbf fd_channel_stream(common_window, common_tw, tns_data_presentch, noiseFilling, indepFlag); “ I
8、SO/IEC 23003-3:2012/Cor.2:2013(E) ISO/IEC 2013 All rights reserved 3With: “ Table 23 Syntax of UsacCoreCoderData() Syntax No. of bits Mnemonic UsacCoreCoderData(nrChannels, indepFlag) for (ch=0; ch nrChannels; ch+) core_modech; 1 uimsbf if (nrChannels = 2) StereoCoreToolInfo(core_mode); for (ch=0; c
9、hnrChannels; ch+) if (core_modech = 1) lpd_channel_stream(indepFlag); NOTE 1 e l s e if ( (nrChannels = 1) | (core_mode0 != core_mode1) ) tns_data_presentch; 1 uimsbf fd_channel_stream(common_window, common_tw, tns_data_presentch, noiseFilling, indepFlag); NOTE 2 Note 1: Each channel shall have its
10、own instance of lpd_channel_stream Note 2: Each channel shall have its own instance of fd_channel_stream “ In Table 23, replace “ if (nrChannels = 2) StereoCoreToolInfo(core_mode); “ With “ if (nrChannels = 2) StereoCoreToolInfo(core_mode, stereoConfigIndex); “ In Table 24, replace “ if (ms_mask_pre
11、sent = 3) cplx_pred_data(); “ ISO/IEC 23003-3:2012/Cor.2:2013(E) 4 ISO/IEC 2013 All rights reservedWith “ if (ms_mask_present = 3) “ In Table 35, replace “ for (k=0; k0) arith_rewind_bitstream(14); for (i=offset ;iN/4;i+) x_ac_dec2*i = 0; x_ac_dec2*i+1 = 0; ISO/IEC 23003-3:2012/Cor.2:2013(E) ISO/IEC
12、 2013 All rights reserved 5, ,q1i = 1; “ In 7.7.2.3.4, replace “ if (ms_mask_present = 3) “ With “ if (ms_mask_present = 3) & (stereoConfigIndex = 0) “ In subclause 7.11.2.3.3, replace “ , 1 , 2 lm lm left lm lm lm left OPD OPD IPD “ With “ , 1 , 2 lm lm left lm lm lm left OPD OPD IPD It is noted th
13、at due to the wrapping property of phase values, the correction angles , 1 lmand , 2 lmare calculated using a modulo 2 operation. “ In 7.11.2.7, replace “ The RES input to the MPS decoder is fed by the 32 QMF band analysis of the RES output from the core decoder, with the upper 32 QMF bands set to z
14、ero (as described in ISO/IEC 23003-1:2007, 6.3.3 for downsampled MPS decoder operation). “ With “ The RES input to the MPS decoder is fed by the 32 (16, 24, depending on sbrRatioIndex) QMF band analysis of the RES output from the core decoder, with the upper 32 (resp. 48, 40) QMF bands set to zero (
15、as described in ISO/IEC 23003-1:2007, 6.3.3 for downsampled MPS decoder operation). “ ISO/IEC 23003-3:2012/Cor.2:2013(E) 6 ISO/IEC 2013 All rights reservedIn 7.11.2.7, replace “ The MPS decoder is fed by the 32 QMF band analysis of the output of the core decoder, with the upper 32 QMF bands set to z
16、ero (as described in ISO/IEC 23003-1:2007, 6.3.3 for downsampled MPS decoder operation). “ With “ The MPS decoder is fed by the 32 (16, 24, depending on sbrRatioIndex) QMF band analysis of the output of the core decoder, with the upper 32 (resp. 48, 40) QMF bands set to zero (as described in ISO/IEC 23003- 1:2007, 6.3.3 for downsampled MPS decoder operation). “