echo-cancel: Split out speex code from the core module

This splits out the echo-cancelling core from the PA-specific bits to
allow us to plug in other echo-cancellation engines.

1 files changed, 64 insertions, 0 deletions

diff --git a/src/modules/echo-cancel/speex.c b/src/modules/echo-cancel/speex.c
new file mode 100644
index 00000000..1b9e76f4
--- /dev/null
+++ b/src/modules/echo-cancel/speex.c
@@ -0,0 +1,64 @@
+/***
+    This file is part of PulseAudio.
+
+    Copyright 2010 Wim Taymans <wim.taymans@gmail.com>
+
+    Contributor: Arun Raghavan <arun.raghavan@collabora.co.uk>
+
+    PulseAudio is free software; you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published
+    by the Free Software Foundation; either version 2.1 of the License,
+    or (at your option) any later version.
+
+    PulseAudio 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 Lesser General Public License
+    along with PulseAudio; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+    USA.
+***/
+
+#include "echo-cancel.h"
+
+pa_bool_t pa_speex_ec_init(pa_echo_canceller *ec, pa_sample_spec ss, pa_channel_map map, uint32_t filter_size_ms, uint32_t frame_size_ms)
+{
+    int framelen, y, rate = ss.rate;
+
+    framelen = (rate * frame_size_ms) / 1000;
+    /* framelen should be a power of 2, round down to nearest power of two */
+    y = 1 << ((8 * sizeof (int)) - 2);
+    while (y > framelen)
+      y >>= 1;
+    framelen = y;
+
+    ec->params.priv.speex.blocksize = framelen * pa_frame_size (&ss);
+
+    pa_log_debug ("Using framelen %d, blocksize %lld, channels %d, rate %d", framelen, (long long) ec->params.priv.speex.blocksize, ss.channels, ss.rate);
+
+    ec->params.priv.speex.state = speex_echo_state_init_mc (framelen, (rate * filter_size_ms) / 1000, ss.channels, ss.channels);
+
+    if (ec->params.priv.speex.state) {
+	speex_echo_ctl(ec->params.priv.speex.state, SPEEX_ECHO_SET_SAMPLING_RATE, &rate);
+	return TRUE;
+    } else
+	return FALSE;
+}
+
+void pa_speex_ec_run(pa_echo_canceller *ec, uint8_t *rec, uint8_t *play, uint8_t *out)
+{
+    speex_echo_cancellation(ec->params.priv.speex.state, (const spx_int16_t *) rec, (const spx_int16_t *) play, (spx_int16_t *) out);
+}
+
+void pa_speex_ec_done(pa_echo_canceller *ec)
+{
+    speex_echo_state_destroy (ec->params.priv.speex.state);
+    ec->params.priv.speex.state = NULL;
+}
+
+uint32_t pa_speex_ec_get_block_size(pa_echo_canceller *ec)
+{
+    return ec->params.priv.speex.blocksize;
+}