I don't understand the comment in src/libFLAC/stream_decoder.c: /*@@@@@@ technically not pessimistic enough, should be more like if( (FLAC__uint64)order * ((((FLAC__uint64)1)<<bps)-1) * ((1<<subframe->qlp_coeff_precision)-1) < (((FLAC__uint64)-1) << 32) ) */ if(bps + subframe->qlp_coeff_precision + FLAC__bitmath_ilog2(order) <= 32)
see http://git.xiph.org/?p=flac.git;a=commitdiff;h=8534bbe4e92300609fd6dc289d882130b69d48cd First, I suspect that there's a typo and the intended code is ... < (((FLAC__uint64)1) << 32) ) (without an unary minus). Second, this condition (in algebraic form) order * (2^bps - 1) * (2^qlp_coeff_precision - 1) < 2^32 makes sense if qlp_coeff[] and data[] in FLAC__lpc_restore_signal() are unsigned integers. But they are signed, and the condition should be order * 2^(bps-1) * 2^(qlp_coeff_precision-1) < 2^31 which is equivalent to the current bps + subframe->qlp_coeff_precision + FLAC__bitmath_ilog2(order) <= 32 So IMHO the comment is incorrect. _______________________________________________ flac-dev mailing list flac-dev@xiph.org http://lists.xiph.org/mailman/listinfo/flac-dev