Add some convenient DSP methods for lua scripts

1 files changed, 56 insertions, 0 deletions

diff --git a/libs/ardour/ardour/dsp_filter.h b/libs/ardour/ardour/dsp_filter.h
index ae2928de93..1b4cb6eed8 100644
--- a/libs/ardour/ardour/dsp_filter.h
+++ b/libs/ardour/ardour/dsp_filter.h
@@ -20,13 +20,69 @@
 #define _dsp_filter_h_
 
 #include <stdint.h>
+#include <string.h>
+#include <assert.h>
+#include <glib.h>
 #include "ardour/libardour_visibility.h"
 
 namespace ARDOUR { namespace DSP {
 
+	/** a convenience class for lua scripts to use C memory for DSP operations.
+	 *
+	 * It should be allocated during dsp_init() or dsp_configure().
+	 */
+	class DspShm {
+		public:
+			DspShm ()
+				: _data (0)
+				, _size (0)
+			{
+				assert (sizeof(float) == sizeof (int32_t));
+				assert (sizeof(float) == sizeof (int));
+			}
+
+			~DspShm () {
+				free (_data);
+			}
+
+			void allocate (size_t s) {
+				_data = realloc (_data, sizeof(float) * s);
+				if (_data) { _size = s; }
+			}
+
+			void clear () {
+				memset (_data, 0, sizeof(float) * _size);
+			}
+
+			float* to_float (size_t off) {
+				if (off >= _size) { return 0; }
+				return &(((float*)_data)[off]);
+			}
+
+			int32_t* to_int (size_t off) {
+				if (off >= _size) { return 0; }
+				return &(((int32_t*)_data)[off]);
+			}
+
+			void atomic_set_int (size_t off, int32_t val) {
+				g_atomic_int_set (&(((int32_t*)_data)[off]), val);
+			}
+
+			int32_t atomic_get_int (size_t off) {
+				return g_atomic_int_get (&(((int32_t*)_data)[off]));
+			}
+
+		private:
+			void* _data;
+			size_t _size;
+	};
+
 	void memset (float *data, const float val, const uint32_t n_samples);
 	void mmult (float *data, float *mult, const uint32_t n_samples);
+	void peaks (float *data, float &min, float &max, uint32_t n_samples);
 
+	float log_meter (float power);
+	float log_meter_coeff (float coeff);
 
 	class LIBARDOUR_API LowPass {
 		public: