out_ndi: Basic NDI Output.

I have a feeling that it's 4:2:2 or 4:2:0, but it works good enough for the Night of Science, I think.

Author: vifino

GNUmakefile

@@ -24,7 +24,7 @@ FLTMODS_AVAILABLE += flt_debug flt_gamma_correct flt_flip_x flt_flip_y flt_scale
 FLTMODS_AVAILABLE += flt_rot_90 flt_smapper flt_channel_reorder
 
 OUTMODS_AVAILABLE := out_dummy out_sdl2 out_rpi_ws2812b out_udp out_fb out_rpi_hub75
-OUTMODS_AVAILABLE += out_sf75_bi_spidev out_ansi out_pixelflut
+OUTMODS_AVAILABLE += out_sf75_bi_spidev out_ansi out_pixelflut out_ndi
 
 # List of modules to compile.
 GFXMODS_DEFAULT := gfx_twinkle gfx_gol gfx_rainbow gfx_math_sinpi gfx_plasma

src/modules/out_ndi.c

@@ -0,0 +1,152 @@
+#include <types.h>
+#include <oscore.h>
+#include <timers.h>
+#include <assert.h>
+#include <pthread.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdatomic.h>
+#include <Processing.NDI.Lib.h>  // NDI SDK headers
+
+// Matrix size
+#ifndef MATRIX_X
+#error Define MATRIX_X as the matrix's X size.
+#endif
+
+#ifndef MATRIX_Y
+#error Define MATRIX_Y as the matrix's Y size.
+#endif
+
+#define FPS 60
+
+static RGB *primary_buffer;
+static RGB *front_buffer;
+static RGB *back_buffer;
+static atomic_bool keep_running;
+static atomic_int front_or_back;
+
+static NDIlib_send_instance_t ndi_send = NULL;
+static oscore_task ndi_task;
+
+static void* send_task(void *arg);
+	
+int init(void) {
+	assert(sizeof(RGB) == 4);
+
+	// Allocate memory for the buffers
+	primary_buffer = (RGB*)malloc(MATRIX_X * MATRIX_Y * sizeof(RGB));
+	front_buffer = (RGB*)malloc(MATRIX_X * MATRIX_Y * sizeof(RGB));
+	back_buffer = (RGB*)malloc(MATRIX_X * MATRIX_Y * sizeof(RGB));
+
+	atomic_init(&keep_running, true);
+	atomic_init(&front_or_back, true);
+
+	// Start the NDI sending task
+	ndi_task = oscore_task_create("NDI Sender", send_task, NULL);
+	return 0;
+}
+
+int getx(int _modno) {
+	return MATRIX_X;
+}
+
+int gety(int _modno) {
+	return MATRIX_Y;
+}
+
+int set(int _modno, int x, int y, RGB color) {
+	primary_buffer[(y * MATRIX_X + x)] = color;
+	return 0;
+}
+
+RGB get(int _modno, int x, int y) {
+	return primary_buffer[(y * MATRIX_X + x)];
+}
+
+int clear(int _modno) {
+	// Clear the primary buffer
+	memset(primary_buffer, 0, MATRIX_X * MATRIX_Y * sizeof(RGB));
+	return 0;
+}
+
+int render(void) {
+	// Get current buffer
+	int current_fob = atomic_load(&front_or_back);
+	RGB *current_buffer = current_fob ? front_buffer : back_buffer;
+
+	// Copy primary buffer to current buffer
+	memcpy(current_buffer, primary_buffer, MATRIX_X * MATRIX_Y * sizeof(RGB));
+
+	// Flip buffers
+	atomic_store(&front_or_back, !current_fob);
+
+	return 0;
+}
+
+oscore_time wait_until(int _modno, oscore_time desired_usec) {
+#ifdef CIMODE
+	return desired_usec;
+#else
+	return timers_wait_until_core(desired_usec);
+#endif
+}
+
+void wait_until_break(int _modno) {
+#ifndef CIMODE
+	timers_wait_until_break_core();
+#endif
+}
+
+void deinit(int _modno) {
+	// Stop the NDI Sender task
+	atomic_store(&keep_running, false);
+	oscore_task_join(&ndi_task);
+
+	// Clean up resources
+	NDIlib_send_destroy(ndi_send);
+	NDIlib_destroy();
+
+	free(primary_buffer);
+	free(front_buffer);
+	free(back_buffer);
+}
+
+// NDI sending function (runs in a separate task)
+static void* send_task(void *arg) {
+	// Create the NDI sender
+	NDIlib_initialize();
+	NDIlib_send_create_t send_create_desc = {0};
+	send_create_desc.p_ndi_name = "SLED";
+	send_create_desc.clock_video = false;
+	send_create_desc.clock_audio = false;
+	ndi_send = NDIlib_send_create(&send_create_desc);
+
+	// Prepopulate frame with static info.
+	NDIlib_video_frame_v2_t video_frame;
+	video_frame.xres = MATRIX_X;
+	video_frame.yres = MATRIX_Y;
+	video_frame.line_stride_in_bytes = MATRIX_X * sizeof(RGB);
+	video_frame.picture_aspect_ratio = (float)MATRIX_X / (float)MATRIX_Y;
+	video_frame.FourCC = NDIlib_FourCC_type_RGBX;
+	video_frame.frame_format_type = NDIlib_frame_format_type_progressive;
+	video_frame.frame_rate_N = FPS * 1000;
+	video_frame.frame_rate_D = 1000;
+	
+	while (atomic_load(&keep_running)) {
+		// Get current buffer
+		int current_fob = atomic_load(&front_or_back);
+
+		// Send a video frame with the actual data.
+		video_frame.p_data = (uint8_t*) (current_fob ? front_buffer : back_buffer);
+		NDIlib_send_send_video_async_v2(ndi_send, &video_frame);
+
+		// Wait for the next frame
+		usleep(1000000 / FPS);
+	}
+
+	// Force sync for last frame.
+	NDIlib_send_send_video_async_v2(ndi_send, NULL);
+	return NULL;
+}
+

src/modules/out_ndi.incs

@@ -0,0 +1 @@
+-I"$NDI_SDK_DIR/include"

src/modules/out_ndi.libs

@@ -0,0 +1 @@
+-L"$NDI_SDK_DIR/lib" -L/usr/local/lib -lndi