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#ifdef CONFIG_OSS_VMIX_FLOAT
This file is part of Open Sound System.
Copyright (C) 4Front Technologies 1996-2008.
This this source file is released under GPL v2 license (no other versions). See the COPYING file included in the main directory of this source distribution for the license terms and conditions.
vmix_mixer_t *mixer = portc->mixer; vmix_engine_t *eng = &mixer->record_engine; dmap_t *dmap = audio_engines[portc->audio_dev]->dmap_in; int frame_size; int outptr, outmax; int used_channels; int i, ch;
Initial setup
frame_size = sizeof (*outp); outmax = dmap->bytes_in_use / frame_size; outptr = portc->rec_dma_pointer / frame_size; outp = (BUFFER_TYPE) dmap->dmabuf; used_channels = portc->channels; if (used_channels > eng->channels) used_channels = eng->channels; /* ignored_channels = portc->channels - used_channels; */
Do the mixing
for (ch = 0; ch < used_channels; ch++) { int op = outptr + ch; float *chbuf = eng->chbufs[ch+portc->rec_choffs]; for (i = 0; i < nsamples; i++) { float tmp; tmp = *chbuf++;
Convert the sample to right endianess.
outp[op] = VMIX_BYTESWAP ((int)(tmp * range)); op = (op + portc->channels) % outmax; } }
Finally save the state variables
portc->rec_dma_pointer = (portc->rec_dma_pointer + nsamples * frame_size * portc->channels) % dmap->bytes_in_use; #else #include "rec_export_int.inc" #endif