audio/mixeng.c

   1 /*
   2  * QEMU Mixing engine
   3  *
   4  * Copyright (c) 2004 Vassili Karpov (malc)
   5  * Copyright (c) 1998 Fabrice Bellard
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  23  * THE SOFTWARE.
  24  */
  25 #include "vl.h"
  26 //#define DEBUG_FP
  27 #include "audio/mixeng.h"
  28
  29 #define IN_T int8_t
  30 #define IN_MIN CHAR_MIN
  31 #define IN_MAX CHAR_MAX
  32 #define SIGNED
  33 #include "mixeng_template.h"
  34 #undef SIGNED
  35 #undef IN_MAX
  36 #undef IN_MIN
  37 #undef IN_T
  38
  39 #define IN_T uint8_t
  40 #define IN_MIN 0
  41 #define IN_MAX UCHAR_MAX
  42 #include "mixeng_template.h"
  43 #undef IN_MAX
  44 #undef IN_MIN
  45 #undef IN_T
  46
  47 #define IN_T int16_t
  48 #define IN_MIN SHRT_MIN
  49 #define IN_MAX SHRT_MAX
  50 #define SIGNED
  51 #include "mixeng_template.h"
  52 #undef SIGNED
  53 #undef IN_MAX
  54 #undef IN_MIN
  55 #undef IN_T
  56
  57 #define IN_T uint16_t
  58 #define IN_MIN 0
  59 #define IN_MAX USHRT_MAX
  60 #include "mixeng_template.h"
  61 #undef IN_MAX
  62 #undef IN_MIN
  63 #undef IN_T
  64
  65 t_sample *mixeng_conv[2][2][2] = {
  66     {
  67         {
  68             conv_uint8_t_to_mono,
  69             conv_uint16_t_to_mono
  70         },
  71         {
  72             conv_int8_t_to_mono,
  73             conv_int16_t_to_mono
  74         }
  75     },
  76     {
  77         {
  78             conv_uint8_t_to_stereo,
  79             conv_uint16_t_to_stereo
  80         },
  81         {
  82             conv_int8_t_to_stereo,
  83             conv_int16_t_to_stereo
  84         }
  85     }
  86 };
  87
  88 f_sample *mixeng_clip[2][2][2] = {
  89     {
  90         {
  91             clip_uint8_t_from_mono,
  92             clip_uint16_t_from_mono
  93         },
  94         {
  95             clip_int8_t_from_mono,
  96             clip_int16_t_from_mono
  97         }
  98     },
  99     {
 100         {
 101             clip_uint8_t_from_stereo,
 102             clip_uint16_t_from_stereo
 103         },
 104         {
 105             clip_int8_t_from_stereo,
 106             clip_int16_t_from_stereo
 107         }
 108     }
 109 };
 110
 111 /*
 112  * August 21, 1998
 113  * Copyright 1998 Fabrice Bellard.
 114  *
 115  * [Rewrote completly the code of Lance Norskog And Sundry
 116  * Contributors with a more efficient algorithm.]
 117  *
 118  * This source code is freely redistributable and may be used for
 119  * any purpose.  This copyright notice must be maintained.
 120  * Lance Norskog And Sundry Contributors are not responsible for
 121  * the consequences of using this software.
 122  */
 123
 124 /*
 125  * Sound Tools rate change effect file.
 126  */
 127 /*
 128  * Linear Interpolation.
 129  *
 130  * The use of fractional increment allows us to use no buffer. It
 131  * avoid the problems at the end of the buffer we had with the old
 132  * method which stored a possibly big buffer of size
 133  * lcm(in_rate,out_rate).
 134  *
 135  * Limited to 16 bit samples and sampling frequency <= 65535 Hz. If
 136  * the input & output frequencies are equal, a delay of one sample is
 137  * introduced.  Limited to processing 32-bit count worth of samples.
 138  *
 139  * 1 << FRAC_BITS evaluating to zero in several places.  Changed with
 140  * an (unsigned long) cast to make it safe.  MarkMLl 2/1/99
 141  */
 142
 143 /* Private data */
 144 typedef struct ratestuff {
 145     uint64_t opos;
 146     uint64_t opos_inc;
 147     uint32_t ipos;              /* position in the input stream (integer) */
 148     st_sample_t ilast;          /* last sample in the input stream */
 149 } *rate_t;
 150
 151 /*
 152  * Prepare processing.
 153  */
 154 void *st_rate_start (int inrate, int outrate)
 155 {
 156     rate_t rate = (rate_t) qemu_mallocz (sizeof (struct ratestuff));
 157
 158     if (!rate) {
 159         exit (EXIT_FAILURE);
 160     }
 161
 162     if (inrate == outrate) {
 163         // exit (EXIT_FAILURE);
 164     }
 165
 166     if (inrate >= 65535 || outrate >= 65535) {
 167         // exit (EXIT_FAILURE);
 168     }
 169
 170     rate->opos = 0;
 171
 172     /* increment */
 173     rate->opos_inc = (inrate * ((int64_t) UINT_MAX)) / outrate;
 174
 175     rate->ipos = 0;
 176     rate->ilast.l = 0;
 177     rate->ilast.r = 0;
 178     return rate;
 179 }
 180
 181 /*
 182  * Processed signed long samples from ibuf to obuf.
 183  * Return number of samples processed.
 184  */
 185 void st_rate_flow (void *opaque, st_sample_t *ibuf, st_sample_t *obuf,
 186                    int *isamp, int *osamp)
 187 {
 188     rate_t rate = (rate_t) opaque;
 189     st_sample_t *istart, *iend;
 190     st_sample_t *ostart, *oend;
 191     st_sample_t ilast, icur, out;
 192     int64_t t;
 193
 194     ilast = rate->ilast;
 195
 196     istart = ibuf;
 197     iend = ibuf + *isamp;
 198
 199     ostart = obuf;
 200     oend = obuf + *osamp;
 201
 202     if (rate->opos_inc == 1ULL << 32) {
 203         int i, n = *isamp > *osamp ? *osamp : *isamp;
 204         for (i = 0; i < n; i++) {
 205             obuf[i].l += ibuf[i].r;
 206             obuf[i].r += ibuf[i].r;
 207         }
 208         *isamp = n;
 209         *osamp = n;
 210         return;
 211     }
 212
 213     while (obuf < oend) {
 214
 215         /* Safety catch to make sure we have input samples.  */
 216         if (ibuf >= iend)
 217             break;
 218
 219         /* read as many input samples so that ipos > opos */
 220
 221         while (rate->ipos <= (rate->opos >> 32)) {
 222             ilast = *ibuf++;
 223             rate->ipos++;
 224             /* See if we finished the input buffer yet */
 225             if (ibuf >= iend) goto the_end;
 226         }
 227
 228         icur = *ibuf;
 229
 230         /* interpolate */
 231         t = rate->opos & 0xffffffff;
 232         out.l = (ilast.l * (INT_MAX - t) + icur.l * t) / INT_MAX;
 233         out.r = (ilast.r * (INT_MAX - t) + icur.r * t) / INT_MAX;
 234
 235         /* output sample & increment position */
 236 #if 0
 237         *obuf++ = out;
 238 #else
 239         obuf->l += out.l;
 240         obuf->r += out.r;
 241         obuf += 1;
 242 #endif
 243         rate->opos += rate->opos_inc;
 244     }
 245
 246 the_end:
 247     *isamp = ibuf - istart;
 248     *osamp = obuf - ostart;
 249     rate->ilast = ilast;
 250 }
 251
 252 void st_rate_stop (void *opaque)
 253 {
 254     qemu_free (opaque);
 255 }