moving ecasound

library/ecasound-2.7.2/examples/ecidoc_example.c

@@ -0,0 +1,59 @@
+/*************************************************************************
+ * Implementation of the following:
+ * 
+ * 1. Setup ECI to read audio from file, apply a 100Hz lowpass filter, and 
+ *    send it to the soundcard (/dev/dsp).
+ * 2. Every second, check the current position. If the stream has
+ *    been running for over 15 seconds, exit immediately. Also,
+ *    every second, increase the lowpass filter's cutoff frequency
+ *    by 500Hz.
+ * 3. Stop the stream (if not already finished) and disconnect the 
+ *    chainsetup. Print chain operator status info.
+ ************************************************************************/
+
+#include <stdio.h>
+#include <unistd.h>
+#include <ecasoundc.h>
+
+/* compile with: 
+ *
+ * gcc -o ecidoc_example ecidoc_example.c `libecasoundc-config --cflags --libs`
+ */
+
+int main(int argc, char *argv[])
+{
+  double cutoff_inc = 500.0;
+
+  eci_init();
+  eci_command("cs-add play_chainsetup");
+  eci_command("c-add 1st_chain");
+  eci_command("ai-add foo.wav");
+  eci_command("ao-add /dev/dsp");
+  eci_command("cop-add -efl:100");
+  eci_command("cop-select 1");
+  eci_command("copp-select 1");
+  eci_command("cs-connect");
+  eci_command("start");
+
+  while(1) {
+    double curpos, next_cutoff;
+
+    sleep(1);
+    eci_command("engine-status");
+    if (strcmp(eci_last_string(), "running") != 0) break;
+    eci_command("get-position");
+    curpos = eci_last_float();
+    if (curpos > 15.0) break;
+    eci_command("copp-get");
+    next_cutoff = cutoff_inc + eci_last_float();
+    eci_command_float_arg("copp-set", next_cutoff);
+  }
+  
+  eci_command("stop");
+  eci_command("cs-disconnect");
+  eci_command("cop-status");
+  printf("Chain operator status: %s", eci_last_string());
+  eci_cleanup();
+
+  return(0);
+}