add audio functions

New functions for audio capture and make LEDs react to music

CHANGES.md

@@ -1,3 +1,6 @@
+# Version 6.1
+* Added functions to make LEDs react to audio input
+
 # Version 6.0
 * Added support for 2D graphics
 * Added virtual channels

README.md

@@ -10,13 +10,13 @@ read the change log to see what is new:
 You can use this with the WS2811, WS2812, SK6812, SK9822 chips.
 
 # Installation
-On the raspberry you open a terminal window and type following commands:
+Standard installation with support for all features use the following commands:
 ```
 sudo apt-get update
-sudo apt-get install gcc make git libjpeg-dev libpng-dev pkg-config
+sudo apt-get install gcc make git libjpeg-dev libpng-dev pkg-config libasound2-dev libcairo2-dev libx11-dev libxcb1-dev libfreetype6-dev
 git clone https://github.com/tom-2015/rpi-ws2812-server.git
 cd rpi-ws2812-server
-make
+make ENABLE_2D=1 ENABLE_AUDIO=1
 sudo chmod +x ws2812svr
 ```
 
@@ -33,6 +33,12 @@ sudo apt-get install pkg-config libcairo2-dev libx11-dev libxcb1-dev libfreetype
 make ENABLE_2D=1
 ```
 
+If you want to use audio commands to make your LEDs react to music input (through USB sound card). You must
+install libasound2-dev and compile with ENABLE_AUDIO=1
+```
+make ENABLE_AUDIO=1
+```
+
 On newer Raspbian (>=Jessie) operating system the audio output is activated by default, you need to disable this:
 You can do this by blacklisting the sound module:
 ```
@@ -325,13 +331,13 @@ color_change <channel>,<start_color>,<stop_color>,<duration>,<start>,<len>
 
 * `chaser` makes a chaser light
 ```
-chaser <channel>,<duration>,<color>,<direction>,<count>,<delay>,<start>,<len>,<brightness>,<loops>
+chaser <channel>,<duration>,<color>,<count>,<direction>,<delay>,<start>,<len>,<brightness>,<loops>
 
 # <channel>     Channel number to use
 # <duration>    Max number of seconds the event may take in seconds (default 10) use 0 to make chaser run forever
 # <color>       Color 000000-FFFFFF to use for chasing leds
-# <direction>   Direction 1 or 0 to indicate forward/backwards direction of movement
 # <count>       Number of LEDs in the chaser that will light up
+# <direction>   Direction 1 or 0 to indicate forward/backwards direction of movement
 # <delay>       Delay between moving one pixel (milliseconds) default is 10ms
 # <start>       Start effect at this led position
 # <len>         Number of leds the chaser will move before starting back start led
@@ -897,4 +903,87 @@ pixel_color <channel>,<x>,<y>,<z>,<color>
 # <y>				Y location to fill
 # <z>				Z location to fill, a.t.m. Z is not supported
 # <color>			Color to set in the pixel
-```
+```
+
+# Audio input
+Since version 6.1 it's possible to make LEDs react to audio input. This audio will be captured from an ALSA sound device (USB sound card,...).
+This requires to compile with the parameter ENABLE_AUDIO=1.
+Before you can use any of the audio commands you first need to start recording, you can do so with the record_audio command.
+NOTE: if you want to use multiple threads each thread needs to run the record_audio command before you can use the audio effect commands.
+
+```
+
+* `record_audio` records audio
+
+```
+record_audio <channel>,<sample_rate>,<sample_count>,<channels>
+
+# <channel>			Channel number
+# <sample_rate>		Here you can change the number of samples per second, default is 24000. Higher will require more CPU but better results with high frequency.
+# <sample_count>	Number of samples to store in the internal buffer before forwarding to DSP. Default is 1024 and you better leave it like that.
+# <channels>		Number of audio channels, default is 2 (stereo)
+```
+
+```
+
+* `light_organ` Generates a light organ, alle LEDs blink to the rhythm of the music.
+
+```
+light_organ <channel>,<color_mode>,<color(s)>,<color_change_delay>,<duration>,<delay>,<start>,<len>
+
+# <channel>				Channel number
+# <color_mode>			Sets how changing of color should behave (default 2).
+# <color(s)>			Give color or multiple colors like FF0000 (red) or FF000000FF000000FF (red,green,blue)
+# <color_change_delay>	Number of seconds to wait before changing the color
+# <duration>			Number of seconds before automatic exit of the command, 0 to run forever.
+# <delay>				Delay between rendering of the strip. default is 25ms increase to make flashing slower
+# <start>				Start at this LED number
+# <len>					Effect for this number of LEDs starting at start
+```
+Color modes:
+0 = 1 fixed color
+1 = color sequence provided in the color(s) argument
+2 = random colors provided in the color(s) argument, color(s) argument can be left empty for some default colors.
+3 = keep existing color in the strip, this must be set first 
+
+```
+
+* `pulses` Generates wave pattern on the LED strip (like a music driven chaser)
+
+```
+pulses <channel>,<threshold>,<color_mode>,<color(s)>,<delay>,<color_change_delay>,<direction>,<duration>,<min_brightness>,<start>,<len>
+
+# <channel>				Channel number
+# <threshold>			Minimum level of audio sample to react, float value range 0-1 default is 0.1, audio sample values <0.1 will be ignored
+# <color_mode>			Sets how changing of color should behave, see light_organ for possible values (default 2).
+# <color(s)>			Give color or multiple colors like FF0000 (red) or FF000000FF000000FF (red,green,blue)
+# <delay>				Delay between rendering of the strip, default 25ms. Decrease to make wave go faster but increase CPU load
+# <color_change_delay>	Number of seconds to wait before changing the color
+# <direction>			Chaser go forward or backwards
+# <duration>			Number of seconds before automatic exit of the command, 0 to run forever.
+# <min_brightness>		Minimum level of brightness or LEDs will be turned off (default is 10 max 255).
+# <start>				Start at this LED number
+# <len>					Effect for this number of LEDs starting at start
+```
+
+* `vu_meter` 
+
+```
+vu_meter <channel>,<color_mode>,<color(s)>,<color_change_delay>,<duration>,<delay>,<brightness>,<start>,<len>
+
+# <channel>				Channel number
+# <color_mode>			Sets how changing of color should behave (default 4).
+# <color(s)>			Give color or multiple colors like FF0000 (red) or FF000000FF000000FF (red,green,blue)
+# <color_change_delay>	Number of seconds to wait before changing the color
+# <duration>			Number of seconds before automatic exit of the command, 0 to run forever.
+# <delay>				Delay between rendering of the strip, default 25ms. Decrease to make wave go faster but increase CPU load
+# <brightness>			Brightness level of turned on LEDs, (0-255) default is 255
+# <start>				Start at this LED number
+# <len>					Effect for this number of LEDs starting at start
+```
+Color modes:
+0 = 1 fixed color
+1 = color sequence provided in the color(s) argument
+2 = random colors provided in the color(s) argument, color(s) argument can be left empty for some default colors.
+3 = keep existing color in the strip, this must be set first 
+4 = Classic VU meter colors (green - yellow - orange - red)

audio/light_organ.c

@@ -0,0 +1,132 @@
+//light_organ <channel>,<color_mode>,<color(s)>,<color_change_delay>,<duration>,<delay>,<start>,<len>
+void light_organ(thread_context* context, char* args) {
+	const unsigned int MAX_COLORS = 255;
+	int channel = 0;
+	int duration = 0;
+	int delay = 25;
+	int len = 0, start = 0;
+	unsigned int next_color = 255;
+	unsigned int colors[MAX_COLORS];
+	int color_count = 0;
+	int color_mode = 2; //default some random colors
+	int color_change_delay = 60; //60 sec change color
+	float gain = 4.0;
+	int i;
+
+	if (!context->audio_capture.capturing) {
+		fprintf(stderr, "Error audio capture is not running on this thread. Use the audio_capture command to start capturing first!\n");
+		return;
+	}
+
+	args = read_channel(args, &channel);
+
+	if (is_valid_channel_number(channel)) {
+		//args = read_float(args, &threshold);
+		args = read_int(args, &color_mode);
+
+		switch (color_mode) {
+		case 0: //fixed color
+			args = read_color_arg(args, &next_color, get_color_size(channel));
+			colors[0] = next_color;
+			break;
+		case 1: //color sequence
+			if (*args == ',') args++;
+			while (color_count < MAX_COLORS && *args != ',' && *args != 0) {
+				args = read_color(args, &colors[color_count], get_color_size(channel));
+				color_count++;
+			}
+			next_color = colors[0];
+			break;
+		case 2: //random colors
+			if (*args == ',') args++;
+			while (color_count < MAX_COLORS && *args != ',' && *args != 0) {
+				args = read_color(args, &colors[color_count], get_color_size(channel));
+				color_count++;
+			}
+			if (color_count == 0) {
+				colors[0] = color(255, 0, 0);
+				colors[1] = color(255, 255, 0);
+				colors[2] = color(0, 255, 255);
+				colors[3] = color(0, 255, 0);
+				colors[4] = color(255, 128, 0);
+				colors[5] = color(255, 0, 128);
+				colors[6] = color(0, 0, 255);
+				color_count = 7;
+			}
+			next_color = colors[0];
+			break;
+		case 3: //don't care about color
+
+			break;
+		default:
+			fprintf(stderr, "Error invalid color mode %d\n", color_mode);
+			return;
+			break;
+		}
+
+		args = read_int(args, &color_change_delay);
+		args = read_int(args, &duration);
+		args = read_int(args, &delay);
+		args = read_int(args, &start);
+		args = read_int(args, &len);
+
+		if (debug) printf("light_organ %d,%d,%d,%d,%d,%d,%d,%d\n", channel, color_mode, color_count, color_change_delay, duration, delay, start, len);
+
+		if (start >= get_led_count(channel)) start = 0;
+		if ((start + len) > get_led_count(channel)) len = get_led_count(channel) - start;
+		if (len == 0) len = get_led_count(channel);
+
+		ws2811_led_t* leds = get_led_string(channel);
+		unsigned int start_time = time(0);
+		unsigned int color_time = time(0);
+		unsigned int next_color_time = color_time;
+		unsigned int color_index = 0;
+		unsigned int current_color = next_color;
+
+		volatile float low_pass_buffer=0; //here the record function will store the number of times threshold was reached
+		context->audio_capture.capture_dst_buffer = (void*)&low_pass_buffer;
+		context->audio_capture.dsp_mode = DSP_MODE_LOW_PASS;
+
+		while ((((time(0) - start_time) < duration) || duration == 0) && context->end_current_command == 0) {
+			float low_pass_value;
+
+			pthread_mutex_lock(&context->audio_capture.buffer_mutex);
+			low_pass_value = low_pass_buffer;
+			pthread_mutex_unlock(&context->audio_capture.buffer_mutex);
+
+			unsigned int intensity = 255.0 * low_pass_value * gain;
+
+			if (color_mode!=3 && next_color_time <= time(0)) {
+				switch (color_mode) {
+				case 0: //fixed color
+					break;
+				case 1: //color sequence
+					next_color = colors[color_index];
+					color_index++;
+					if (color_index == color_count) color_index = 0;
+					break;
+				case 2: //random color from color list
+					color_index = (float)color_count * ((float)rand() / (float)RAND_MAX);
+					next_color = colors[color_index];
+					break;
+				}
+				next_color_time = time(0) + color_change_delay;
+				for (i = 0;i < len;i++) {
+					leds[start + i].color = next_color;
+				}
+			}
+
+			for (i = 0;i < len;i++) {
+				leds[start + i].brightness = intensity;
+			}
+
+			render_channel(channel);
+			usleep(delay * 1000);
+
+		}
+		context->audio_capture.dsp_mode = DSP_MODE_NONE;
+	}
+	else {
+		fprintf(stderr, ERROR_INVALID_CHANNEL);
+	}
+}