diff options
Diffstat (limited to 'qemu/audio/rate_template.h')
-rw-r--r-- | qemu/audio/rate_template.h | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/qemu/audio/rate_template.h b/qemu/audio/rate_template.h new file mode 100644 index 000000000..bd4b1c768 --- /dev/null +++ b/qemu/audio/rate_template.h @@ -0,0 +1,111 @@ +/* + * QEMU Mixing engine + * + * Copyright (c) 2004-2005 Vassili Karpov (malc) + * Copyright (c) 1998 Fabrice Bellard + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +/* + * Processed signed long samples from ibuf to obuf. + * Return number of samples processed. + */ +void NAME (void *opaque, struct st_sample *ibuf, struct st_sample *obuf, + int *isamp, int *osamp) +{ + struct rate *rate = opaque; + struct st_sample *istart, *iend; + struct st_sample *ostart, *oend; + struct st_sample ilast, icur, out; +#ifdef FLOAT_MIXENG + mixeng_real t; +#else + int64_t t; +#endif + + ilast = rate->ilast; + + istart = ibuf; + iend = ibuf + *isamp; + + ostart = obuf; + oend = obuf + *osamp; + + if (rate->opos_inc == (1ULL + UINT_MAX)) { + int i, n = *isamp > *osamp ? *osamp : *isamp; + for (i = 0; i < n; i++) { + OP (obuf[i].l, ibuf[i].l); + OP (obuf[i].r, ibuf[i].r); + } + *isamp = n; + *osamp = n; + return; + } + + while (obuf < oend) { + + /* Safety catch to make sure we have input samples. */ + if (ibuf >= iend) { + break; + } + + /* read as many input samples so that ipos > opos */ + + while (rate->ipos <= (rate->opos >> 32)) { + ilast = *ibuf++; + rate->ipos++; + /* See if we finished the input buffer yet */ + if (ibuf >= iend) { + goto the_end; + } + } + + icur = *ibuf; + + /* interpolate */ +#ifdef FLOAT_MIXENG +#ifdef RECIPROCAL + t = (rate->opos & UINT_MAX) * (1.f / UINT_MAX); +#else + t = (rate->opos & UINT_MAX) / (mixeng_real) UINT_MAX; +#endif + out.l = (ilast.l * (1.0 - t)) + icur.l * t; + out.r = (ilast.r * (1.0 - t)) + icur.r * t; +#else + t = rate->opos & 0xffffffff; + out.l = (ilast.l * ((int64_t) UINT_MAX - t) + icur.l * t) >> 32; + out.r = (ilast.r * ((int64_t) UINT_MAX - t) + icur.r * t) >> 32; +#endif + + /* output sample & increment position */ + OP (obuf->l, out.l); + OP (obuf->r, out.r); + obuf += 1; + rate->opos += rate->opos_inc; + } + +the_end: + *isamp = ibuf - istart; + *osamp = obuf - ostart; + rate->ilast = ilast; +} + +#undef NAME +#undef OP |