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authorJedidiah Barber <contact@jedbarber.id.au>2023-06-19 22:15:44 +1200
committerJedidiah Barber <contact@jedbarber.id.au>2023-06-19 22:15:44 +1200
commit74af58587359206ef92249d18e4830c40cac0bc5 (patch)
tree8dfae06813f8e9f41787e45e7e31354b017f5713 /example
Initial commit
Diffstat (limited to 'example')
-rw-r--r--example/aao_example.adb101
-rw-r--r--example/ao_example.c87
2 files changed, 188 insertions, 0 deletions
diff --git a/example/aao_example.adb b/example/aao_example.adb
new file mode 100644
index 0000000..7d12b56
--- /dev/null
+++ b/example/aao_example.adb
@@ -0,0 +1,101 @@
+
+
+-- Programmed by Jedidiah Barber
+-- Released into the public domain
+
+-- This program opens the default libao driver and plays a 440 Hz tone for one second
+
+
+with
+
+ Ada.Command_Line,
+ Ada.Numerics.Elementary_Functions,
+ Ada.Text_IO,
+ Libao;
+
+
+procedure AAO_Example is
+
+ package ACom renames Ada.Command_Line;
+ package Math renames Ada.Numerics.Elementary_Functions;
+ package TIO renames Ada.Text_IO;
+
+ My_Device : Libao.Device;
+ My_Format : Libao.Sample_Format;
+
+ Default_Driver : Libao.Driver_ID_Number;
+
+begin
+
+ -- Initialize
+
+ TIO.Put_Line ("libao example program");
+
+ Libao.Startup;
+
+
+ -- Setup for default driver
+
+ Default_Driver := Libao.Default_Driver_ID;
+
+ My_Format := Libao.Create
+ (Bits => 16,
+ Rate => 44100,
+ Channels => 2,
+ Byte_Format => Libao.Little_Endian,
+ Channel_Matrix => Libao.Stereo);
+
+
+ -- Open driver
+
+ begin
+ My_Device := Libao.Open_Live
+ (Driver_ID => Default_Driver,
+ Format => My_Format,
+ Options => Libao.Empty_Options);
+ exception
+ when Libao.Open_Device_Error | Libao.General_Failure =>
+ TIO.Put_Line ("Error opening device.");
+ ACom.Set_Exit_Status (ACom.Failure);
+ return;
+ end;
+
+
+ -- Play some stuff
+
+ -- This sine wave generation was directly translated from the C example,
+ -- but it ends up being a little messy playing fast and loose like this.
+
+ declare
+ Buffer : Libao.Data_Buffer (1 .. 16 / 8 * 2 * 44100);
+
+ type Wraparound is mod 65536;
+ Sample : Wraparound;
+ begin
+ for I in Integer range 0 .. 44100 - 1 loop
+ Sample := Wraparound (Integer (0.75 * 32768.0 *
+ Math.Sin (2.0 * Ada.Numerics.Pi * 440.0 * Float (I) / 44100.0)) mod 65536);
+
+ -- Put the same stuff in left and right channel
+ Buffer (4 * I + 1) := Character'Val (Sample and 16#FF#);
+ Buffer (4 * I + 2) := Character'Val ((Sample / 256) and 16#FF#);
+ Buffer (4 * I + 3) := Character'Val (Sample and 16#FF#);
+ Buffer (4 * I + 4) := Character'Val ((Sample / 256) and 16#FF#);
+ end loop;
+
+ Libao.Play (My_Device, Buffer);
+ end;
+
+
+ -- Close and shutdown
+
+ -- Technically the binding will take care of closing open devices at shutdown,
+ -- but it is always good practice to close them anyway.
+
+ Libao.Close (My_Device);
+
+ Libao.Shutdown;
+
+end AAO_Example;
+
+
diff --git a/example/ao_example.c b/example/ao_example.c
new file mode 100644
index 0000000..a5642a0
--- /dev/null
+++ b/example/ao_example.c
@@ -0,0 +1,87 @@
+/*
+ *
+ * ao_example.c
+ *
+ * Written by Stan Seibert - July 2001
+ *
+ * Legal Terms:
+ *
+ * This source file is released into the public domain. It is
+ * distributed without any warranty; without even the implied
+ * warranty * of merchantability or fitness for a particular
+ * purpose.
+ *
+ * Function:
+ *
+ * This program opens the default driver and plays a 440 Hz tone for
+ * one second.
+ *
+ * Compilation command line (for Linux systems):
+ *
+ * gcc -o ao_example ao_example.c -lao -ldl -lm
+ *
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <ao/ao.h>
+#include <math.h>
+
+#define BUF_SIZE 4096
+
+int main()
+{
+ ao_device *device;
+ ao_sample_format format;
+ int default_driver;
+ char *buffer;
+ int buf_size;
+ int sample;
+ float freq = 440.0;
+ int i;
+
+ /* -- Initialize -- */
+
+ fprintf(stderr, "libao example program\n");
+
+ ao_initialize();
+
+ /* -- Setup for default driver -- */
+
+ default_driver = ao_default_driver_id();
+
+ memset(&format, 0, sizeof(format));
+ format.bits = 16;
+ format.channels = 2;
+ format.rate = 44100;
+ format.byte_format = AO_FMT_LITTLE;
+
+ /* -- Open driver -- */
+ device = ao_open_live(default_driver, &format, NULL /* no options */);
+ if (device == NULL) {
+ fprintf(stderr, "Error opening device.\n");
+ return 1;
+ }
+
+ /* -- Play some stuff -- */
+ buf_size = format.bits/8 * format.channels * format.rate;
+ buffer = calloc(buf_size,
+ sizeof(char));
+
+ for (i = 0; i < format.rate; i++) {
+ sample = (int)(0.75 * 32768.0 *
+ sin(2 * M_PI * freq * ((float) i/format.rate)));
+
+ /* Put the same stuff in left and right channel */
+ buffer[4*i] = buffer[4*i+2] = sample & 0xff;
+ buffer[4*i+1] = buffer[4*i+3] = (sample >> 8) & 0xff;
+ }
+ ao_play(device, buffer, buf_size);
+
+ /* -- Close and shutdown -- */
+ ao_close(device);
+
+ ao_shutdown();
+
+ return (0);
+}