aboutsummaryrefslogtreecommitdiffstats
path: root/codecs/mp3/src/cupL1.c
diff options
context:
space:
mode:
authormarkster <markster@f38db490-d61c-443f-a65b-d21fe96a405b>1999-12-07 05:57:45 +0000
committermarkster <markster@f38db490-d61c-443f-a65b-d21fe96a405b>1999-12-07 05:57:45 +0000
commit203a586f28972e48fdb9522afc9d8ac1d6106c3b (patch)
tree83146ef6a16d720b3ba3c8db0e34b5dcb92239e5 /codecs/mp3/src/cupL1.c
parent9bea3cc618bdaa5d09c433987d47f1532a31227c (diff)
Version 0.1.1 from FTP
git-svn-id: http://svn.digium.com/svn/asterisk/trunk@118 f38db490-d61c-443f-a65b-d21fe96a405b
Diffstat (limited to 'codecs/mp3/src/cupL1.c')
-rwxr-xr-xcodecs/mp3/src/cupL1.c319
1 files changed, 319 insertions, 0 deletions
diff --git a/codecs/mp3/src/cupL1.c b/codecs/mp3/src/cupL1.c
new file mode 100755
index 000000000..84b46d24d
--- /dev/null
+++ b/codecs/mp3/src/cupL1.c
@@ -0,0 +1,319 @@
+/*____________________________________________________________________________
+
+ FreeAmp - The Free MP3 Player
+
+ MP3 Decoder originally Copyright (C) 1995-1997 Xing Technology
+ Corp. http://www.xingtech.com
+
+ Portions Copyright (C) 1998-1999 EMusic.com
+
+ 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ $Id$
+____________________________________________________________________________*/
+
+/**** cupL1.c ***************************************************
+
+MPEG audio decoder Layer I mpeg1 and mpeg2
+
+include to clup.c
+
+
+******************************************************************/
+/*======================================================================*/
+
+
+/* Read Only */
+static int bat_bit_masterL1[] =
+{
+ 0, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16};
+
+/*======================================================================*/
+static void unpack_baL1(MPEG *m)
+{
+ int j;
+ int nstereo;
+
+ m->cup.bit_skip = 0;
+ nstereo = m->cup.stereo_sb;
+
+ for (j = 0; j < m->cup.nbatL1; j++)
+ {
+ mac_load_check(4);
+ m->cup.ballo[j] = m->cup.samp_dispatch[j] = mac_load(4);
+ if (j >= m->cup.nsb_limit)
+ m->cup.bit_skip += bat_bit_masterL1[m->cup.samp_dispatch[j]];
+ m->cup.c_value[j] = m->cup.look_c_valueL1[m->cup.samp_dispatch[j]];
+ if (--nstereo < 0)
+ {
+ m->cup.ballo[j + 1] = m->cup.ballo[j];
+ m->cup.samp_dispatch[j] += 15; /* flag as joint */
+ m->cup.samp_dispatch[j + 1] = m->cup.samp_dispatch[j]; /* flag for sf */
+ m->cup.c_value[j + 1] = m->cup.c_value[j];
+ j++;
+ }
+ }
+/*-- terminate with bit skip and end --*/
+ m->cup.samp_dispatch[m->cup.nsb_limit] = 31;
+ m->cup.samp_dispatch[j] = 30;
+}
+/*-------------------------------------------------------------------------*/
+static void unpack_sfL1(MPEG *m) /* unpack scale factor */
+{ /* combine dequant and scale factors */
+ int i;
+
+ for (i = 0; i < m->cup.nbatL1; i++)
+ {
+ if (m->cup.ballo[i])
+ {
+ mac_load_check(6);
+ m->cup.cs_factorL1[i] = m->cup.c_value[i] * m->cup.sf_table[mac_load(6)];
+ }
+ }
+/*-- done --*/
+}
+/*-------------------------------------------------------------------------*/
+#define UNPACKL1_N(n) s[k] = m->cup.cs_factorL1[k]*(load(m,n)-((1 << (n-1)) -1)); \
+ goto dispatch;
+#define UNPACKL1J_N(n) tmp = (load(m,n)-((1 << (n-1)) -1)); \
+ s[k] = m->cup.cs_factorL1[k]*tmp; \
+ s[k+1] = m->cup.cs_factorL1[k+1]*tmp; \
+ k++; \
+ goto dispatch;
+/*-------------------------------------------------------------------------*/
+static void unpack_sampL1(MPEG *m) /* unpack samples */
+{
+ int j, k;
+ float *s;
+ long tmp;
+
+ s = m->cup.sample;
+ for (j = 0; j < 12; j++)
+ {
+ k = -1;
+ dispatch:switch (m->cup.samp_dispatch[++k])
+ {
+ case 0:
+ s[k] = 0.0F;
+ goto dispatch;
+ case 1:
+ UNPACKL1_N(2) /* 3 levels */
+ case 2:
+ UNPACKL1_N(3) /* 7 levels */
+ case 3:
+ UNPACKL1_N(4) /* 15 levels */
+ case 4:
+ UNPACKL1_N(5) /* 31 levels */
+ case 5:
+ UNPACKL1_N(6) /* 63 levels */
+ case 6:
+ UNPACKL1_N(7) /* 127 levels */
+ case 7:
+ UNPACKL1_N(8) /* 255 levels */
+ case 8:
+ UNPACKL1_N(9) /* 511 levels */
+ case 9:
+ UNPACKL1_N(10) /* 1023 levels */
+ case 10:
+ UNPACKL1_N(11) /* 2047 levels */
+ case 11:
+ UNPACKL1_N(12) /* 4095 levels */
+ case 12:
+ UNPACKL1_N(13) /* 8191 levels */
+ case 13:
+ UNPACKL1_N(14) /* 16383 levels */
+ case 14:
+ UNPACKL1_N(15) /* 32767 levels */
+/* -- joint ---- */
+ case 15 + 0:
+ s[k + 1] = s[k] = 0.0F;
+ k++; /* skip right chan dispatch */
+ goto dispatch;
+/* -- joint ---- */
+ case 15 + 1:
+ UNPACKL1J_N(2) /* 3 levels */
+ case 15 + 2:
+ UNPACKL1J_N(3) /* 7 levels */
+ case 15 + 3:
+ UNPACKL1J_N(4) /* 15 levels */
+ case 15 + 4:
+ UNPACKL1J_N(5) /* 31 levels */
+ case 15 + 5:
+ UNPACKL1J_N(6) /* 63 levels */
+ case 15 + 6:
+ UNPACKL1J_N(7) /* 127 levels */
+ case 15 + 7:
+ UNPACKL1J_N(8) /* 255 levels */
+ case 15 + 8:
+ UNPACKL1J_N(9) /* 511 levels */
+ case 15 + 9:
+ UNPACKL1J_N(10) /* 1023 levels */
+ case 15 + 10:
+ UNPACKL1J_N(11) /* 2047 levels */
+ case 15 + 11:
+ UNPACKL1J_N(12) /* 4095 levels */
+ case 15 + 12:
+ UNPACKL1J_N(13) /* 8191 levels */
+ case 15 + 13:
+ UNPACKL1J_N(14) /* 16383 levels */
+ case 15 + 14:
+ UNPACKL1J_N(15) /* 32767 levels */
+
+/* -- end of dispatch -- */
+ case 31:
+ skip(m,m->cup.bit_skip);
+ case 30:
+ s += 64;
+ } /* end switch */
+ } /* end j loop */
+
+/*-- done --*/
+}
+/*-------------------------------------------------------------------*/
+IN_OUT L1audio_decode(void *mv, unsigned char *bs, signed short *pcm)
+{
+ MPEG *m = mv;
+ int sync, prot;
+ IN_OUT in_out;
+
+ load_init(m, bs); /* initialize bit getter */
+/* test sync */
+ in_out.in_bytes = 0; /* assume fail */
+ in_out.out_bytes = 0;
+ sync = load(m,12);
+ if (sync != 0xFFF)
+ return in_out; /* sync fail */
+
+
+ load(m,3); /* skip id and option (checked by init) */
+ prot = load(m,1); /* load prot bit */
+ load(m,6); /* skip to pad */
+ m->cup.pad = (load(m,1)) << 2;
+ load(m,1); /* skip to mode */
+ m->cup.stereo_sb = look_joint[load(m,4)];
+ if (prot)
+ load(m,4); /* skip to data */
+ else
+ load(m,20); /* skip crc */
+
+ unpack_baL1(m); /* unpack bit allocation */
+ unpack_sfL1(m); /* unpack scale factor */
+ unpack_sampL1(m); /* unpack samples */
+
+ m->cup.sbt(m, m->cup.sample, pcm, 12);
+/*-----------*/
+ in_out.in_bytes = m->cup.framebytes + m->cup.pad;
+ in_out.out_bytes = m->cup.outbytes;
+
+ return in_out;
+}
+/*-------------------------------------------------------------------------*/
+int L1audio_decode_init(MPEG *m, MPEG_HEAD * h, int framebytes_arg,
+ int reduction_code, int transform_code, int convert_code,
+ int freq_limit)
+{
+ int i, k;
+ long samprate;
+ int limit;
+ long step;
+ int bit_code;
+
+/*--- sf init done by layer II init ---*/
+ if (m->cup.first_pass_L1)
+ {
+ for (step = 4, i = 1; i < 16; i++, step <<= 1)
+ m->cup.look_c_valueL1[i] = (float) (2.0 / (step - 1));
+ m->cup.first_pass_L1 = 0;
+ }
+
+ transform_code = transform_code; /* not used, asm compatability */
+
+ bit_code = 0;
+ if (convert_code & 8)
+ bit_code = 1;
+ convert_code = convert_code & 3; /* higher bits used by dec8 freq cvt */
+ if (reduction_code < 0)
+ reduction_code = 0;
+ if (reduction_code > 2)
+ reduction_code = 2;
+ if (freq_limit < 1000)
+ freq_limit = 1000;
+
+
+ m->cup.framebytes = framebytes_arg;
+/* check if code handles */
+ if (h->option != 3)
+ return 0; /* layer I only */
+
+ m->cup.nbatL1 = 32;
+ m->cup.max_sb = m->cup.nbatL1;
+/*----- compute nsb_limit --------*/
+ samprate = sr_table[4 * h->id + h->sr_index];
+ m->cup.nsb_limit = (freq_limit * 64L + samprate / 2) / samprate;
+/*- caller limit -*/
+/*---- limit = 0.94*(32>>reduction_code); ----*/
+ limit = (32 >> reduction_code);
+ if (limit > 8)
+ limit--;
+ if (m->cup.nsb_limit > limit)
+ m->cup.nsb_limit = limit;
+ if (m->cup.nsb_limit > m->cup.max_sb)
+ m->cup.nsb_limit = m->cup.max_sb;
+
+ m->cup.outvalues = 384 >> reduction_code;
+ if (h->mode != 3)
+ { /* adjust for 2 channel modes */
+ m->cup.nbatL1 *= 2;
+ m->cup.max_sb *= 2;
+ m->cup.nsb_limit *= 2;
+ }
+
+/* set sbt function */
+ k = 1 + convert_code;
+ if (h->mode == 3)
+ {
+ k = 0;
+ }
+ m->cup.sbt = sbt_table[bit_code][reduction_code][k];
+ m->cup.outvalues *= out_chans[k];
+
+ if (bit_code)
+ m->cup.outbytes = m->cup.outvalues;
+ else
+ m->cup.outbytes = sizeof(short) * m->cup.outvalues;
+
+ m->cup.decinfo.channels = out_chans[k];
+ m->cup.decinfo.outvalues = m->cup.outvalues;
+ m->cup.decinfo.samprate = samprate >> reduction_code;
+ if (bit_code)
+ m->cup.decinfo.bits = 8;
+ else
+ m->cup.decinfo.bits = sizeof(short) * 8;
+
+ m->cup.decinfo.framebytes = m->cup.framebytes;
+ m->cup.decinfo.type = 0;
+
+
+/* clear sample buffer, unused sub bands must be 0 */
+ for (i = 0; i < 768; i++)
+ m->cup.sample[i] = 0.0F;
+
+
+/* init sub-band transform */
+ sbt_init();
+
+ return 1;
+}
+/*---------------------------------------------------------*/