Diffstat (limited to 'core/multimedia/opieplayer/libmad/layer12.c') (more/less context) (ignore whitespace changes)
| -rw-r--r-- | core/multimedia/opieplayer/libmad/layer12.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/core/multimedia/opieplayer/libmad/layer12.c b/core/multimedia/opieplayer/libmad/layer12.c index 41b17ca..d291174 100644 --- a/core/multimedia/opieplayer/libmad/layer12.c +++ b/core/multimedia/opieplayer/libmad/layer12.c @@ -1,98 +1,98 @@ /* - * mad - MPEG audio decoder + * libmad - MPEG audio decoder library * Copyright (C) 2000-2001 Robert Leslie * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * $Id$ */ # ifdef HAVE_CONFIG_H # include "libmad_config.h" # endif # include "libmad_global.h" # ifdef HAVE_LIMITS_H # include <limits.h> # else # define CHAR_BIT 8 # endif # include "fixed.h" # include "bit.h" # include "stream.h" # include "frame.h" # include "layer12.h" /* * scalefactor table * used in both Layer I and Layer II decoding */ static mad_fixed_t const sf_table[63] = { # include "sf_table.dat" }; /* --- Layer I ------------------------------------------------------------- */ /* linear scaling table */ static mad_fixed_t const linear_table[14] = { MAD_F(0x15555555), /* 2^2 / (2^2 - 1) == 1.33333333333333 */ MAD_F(0x12492492), /* 2^3 / (2^3 - 1) == 1.14285714285714 */ MAD_F(0x11111111), /* 2^4 / (2^4 - 1) == 1.06666666666667 */ MAD_F(0x10842108), /* 2^5 / (2^5 - 1) == 1.03225806451613 */ MAD_F(0x10410410), /* 2^6 / (2^6 - 1) == 1.01587301587302 */ MAD_F(0x10204081), /* 2^7 / (2^7 - 1) == 1.00787401574803 */ MAD_F(0x10101010), /* 2^8 / (2^8 - 1) == 1.00392156862745 */ MAD_F(0x10080402), /* 2^9 / (2^9 - 1) == 1.00195694716243 */ MAD_F(0x10040100), /* 2^10 / (2^10 - 1) == 1.00097751710655 */ MAD_F(0x10020040), /* 2^11 / (2^11 - 1) == 1.00048851978505 */ MAD_F(0x10010010), /* 2^12 / (2^12 - 1) == 1.00024420024420 */ MAD_F(0x10008004), /* 2^13 / (2^13 - 1) == 1.00012208521548 */ MAD_F(0x10004001), /* 2^14 / (2^14 - 1) == 1.00006103888177 */ MAD_F(0x10002000) /* 2^15 / (2^15 - 1) == 1.00003051850948 */ }; /* * NAME: I_sample() * DESCRIPTION: decode one requantized Layer I sample from a bitstream */ static mad_fixed_t I_sample(struct mad_bitptr *ptr, unsigned int nb) { mad_fixed_t sample; sample = mad_bit_read(ptr, nb); /* invert most significant bit, extend sign, then scale to fixed format */ sample ^= 1 << (nb - 1); sample |= -(sample & (1 << (nb - 1))); sample <<= MAD_F_FRACBITS - (nb - 1); /* requantize the sample */ /* s'' = (2^nb / (2^nb - 1)) * (s''' + 2^(-nb + 1)) */ sample += MAD_F_ONE >> (nb - 1); return mad_f_mul(sample, linear_table[nb - 2]); /* s' = factor * s'' */ /* (to be performed by caller) */ } |