1 files changed, 135 insertions, 0 deletions

diff --git a/core/multimedia/opieplayer/libmpeg3/audio/uncouple.c b/core/multimedia/opieplayer/libmpeg3/audio/uncouple.c
new file mode 100644
index 0000000..d87a078
--- a/dev/null
+++ b/core/multimedia/opieplayer/libmpeg3/audio/uncouple.c
@@ -0,0 +1,135 @@
+/* 
+ *
+         *uncouple.c Copyright (C) Aaron Holtzman - May 1999
+ *
+ *  This file is part of libmpeg3
+         *
+ *  libmpeg3 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, or (at your option)
+ *  any later version.
+ *   
+ *  libmpeg3 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 GNU Make; see the file COPYING.  If not, write to
+ *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. 
+ *
+ */
+
+#include "../bitstream.h"
+#include "mpeg3audio.h"
+
+static unsigned char mpeg3_first_bit_lut[256] = 
+{
+        0, 8, 7, 7, 6, 6, 6, 6, 5, 5, 5, 5, 5, 5, 5, 5, 
+        4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 
+        3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 
+        3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 
+        2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 
+        2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+        2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+        2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
+};
+
+/* Converts an unsigned exponent in the range of 0-24 and a 16 bit mantissa
+ * to an IEEE single precision floating point value */
+static inline void mpeg3audio_ac3_convert_to_float(unsigned short exp, 
+        unsigned short mantissa, 
+        unsigned MPEG3_INT32 *dest)
+{
+        int num;
+        short exponent;
+        int i;
+
+/* If the mantissa is zero we can simply return zero */
+        if(mantissa == 0)
+        {
+                *dest = 0;
+                return;
+        }
+
+/* Exponent is offset by 127 in IEEE format minus the shift to
+ * align the mantissa to 1.f (subtracted in the final result) */
+        exponent = 127 - exp;
+
+/* Take care of the one asymmetric negative number */
+        if(mantissa == 0x8000)
+                mantissa++;
+
+/* Extract the sign bit, invert the mantissa if it's negative, and 
+   shift out the sign bit */
+        if(mantissa & 0x8000)
+        {
+                mantissa *= -1;
+                num = 0x80000000 + (exponent << 23);
+        }
+        else
+        {
+                mantissa *= 1;
+                num = exponent << 23;
+        }
+
+/* Find the index of the most significant one bit */
+        i = mpeg3_first_bit_lut[mantissa >> 8];
+
+        if(i == 0)
+                i = mpeg3_first_bit_lut[mantissa & 0xff] + 8;
+
+        *dest = num - (i << 23) + (mantissa << (7 + i));
+        return;
+}
+
+
+int mpeg3audio_ac3_uncouple(mpeg3audio_t *audio, 
+                mpeg3_ac3bsi_t *bsi,
+                mpeg3_ac3audblk_t *audblk,
+                mpeg3_stream_coeffs_t *coeffs)
+{
+        int i, j;
+
+        for(i = 0; i < bsi->nfchans; i++)
+        {
+                for(j = 0; j < audblk->endmant[i]; j++)
+                         mpeg3audio_ac3_convert_to_float(audblk->fbw_exp[i][j], 
+                                        audblk->chmant[i][j],
+                                        (unsigned MPEG3_INT32*)&coeffs->fbw[i][j]);
+        }
+
+        if(audblk->cplinu)
+        {
+                for(i = 0; i < bsi->nfchans; i++)
+                {
+                        if(audblk->chincpl[i])
+                        {
+                                mpeg3audio_ac3_uncouple_channel(audio, 
+                                        coeffs,
+                                        audblk,
+                                        i);
+                        }
+                }
+
+        }
+
+        if(bsi->lfeon)
+        {
+/* There are always 7 mantissas for lfe */
+                for(j = 0; j < 7 ; j++)
+                         mpeg3audio_ac3_convert_to_float(audblk->lfe_exp[j], 
+                                        audblk->lfemant[j],
+                                         (unsigned MPEG3_INT32*)&coeffs->lfe[j]);
+
+        }
+        return 0;
+}