X-Git-Url: https://scm.cri.ensmp.fr/git/Faustine.git/blobdiff_plain/e775f23a10c4ba37fc1a762299f52cd0d71593b7..f1f94803668061f90a5ce88bf06ee72bba8e41a5:/interpretor/lib/src/libsndfile-1.0.25/src/GSM610/decode.c diff --git a/interpretor/lib/src/libsndfile-1.0.25/src/GSM610/decode.c b/interpretor/lib/src/libsndfile-1.0.25/src/GSM610/decode.c new file mode 100644 index 0000000..350df12 --- /dev/null +++ b/interpretor/lib/src/libsndfile-1.0.25/src/GSM610/decode.c @@ -0,0 +1,59 @@ +/* + * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische + * Universitaet Berlin. See the accompanying file "COPYRIGHT" for + * details. THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE. + */ + +#include + +#include "gsm610_priv.h" + +/* + * 4.3 FIXED POINT IMPLEMENTATION OF THE RPE-LTP DECODER + */ + +static void Postprocessing ( + struct gsm_state * S, + register word * s) +{ + register int k; + register word msr = S->msr; + register word tmp; + + for (k = 160; k--; s++) { + tmp = GSM_MULT_R( msr, 28180 ); + msr = GSM_ADD(*s, tmp); /* Deemphasis */ + *s = GSM_ADD(msr, msr) & 0xFFF8; /* Truncation & Upscaling */ + } + S->msr = msr; +} + +void Gsm_Decoder ( + struct gsm_state * S, + + word * LARcr, /* [0..7] IN */ + + word * Ncr, /* [0..3] IN */ + word * bcr, /* [0..3] IN */ + word * Mcr, /* [0..3] IN */ + word * xmaxcr, /* [0..3] IN */ + word * xMcr, /* [0..13*4] IN */ + + word * s) /* [0..159] OUT */ +{ + int j, k; + word erp[40], wt[160]; + word * drp = S->dp0 + 120; + + for (j=0; j <= 3; j++, xmaxcr++, bcr++, Ncr++, Mcr++, xMcr += 13) { + + Gsm_RPE_Decoding( /*-S,-*/ *xmaxcr, *Mcr, xMcr, erp ); + Gsm_Long_Term_Synthesis_Filtering( S, *Ncr, *bcr, erp, drp ); + + for (k = 0; k <= 39; k++) wt[ j * 40 + k ] = drp[ k ]; + } + + Gsm_Short_Term_Synthesis_Filter( S, LARcr, wt, s ); + Postprocessing(S, s); +} +