Merge branch 'develop'

[lcr.git] / gsm_bs.cpp

diff --git a/gsm_bs.cpp b/gsm_bs.cpp
index e25732a..22ac70c 100644 (file)
--- a/gsm_bs.cpp
+++ b/gsm_bs.cpp
@@ -57,6 +57,34 @@ void generate_dtmf(void)
 
 
 /*
+ * DTMF stuff
+ */
+unsigned char dtmf_samples[16][8000];
+static int dtmf_x[4] = { 1209, 1336, 1477, 1633 };
+static int dtmf_y[4] = { 697, 770, 852, 941 };
+
+void generate_dtmf(void)
+{
+       double fx, fy, sample;
+       int i, x, y;
+       unsigned char *law;
+
+       for (y = 0; y < 4; y++) {
+               fy = 2 * 3.1415927 * ((double)dtmf_y[y]) / 8000.0;
+               for (x = 0; x < 4; x++) {
+                       fx = 2 * 3.1415927 * ((double)dtmf_x[x]) / 8000.0;
+                       law = dtmf_samples[y << 2 | x];
+                       for (i = 0; i < 8000; i++) {
+                               sample = sin(fy * ((double)i)) * 0.251 * 32767.0; /* -6 dB */
+                               sample += sin(fx * ((double)i)) * 0.158 * 32767.0; /* -8 dB */
+                               *law++ = audio_s16_to_law[(int)sample & 0xffff];
+                       }
+               }
+       }
+}
+
+
+/*
  * constructor
  */
 Pgsm_bs::Pgsm_bs(int type, struct mISDNport *mISDNport, char *portname, struct port_settings *settings, int channel, int exclusive, int mode) : Pgsm(type, mISDNport, portname, settings, channel, exclusive, mode)