add an plugin API to query generic-gui grid-layout

[ardour.git] / libs / ardour / ardour / dsp_filter.h

diff --git a/libs/ardour/ardour/dsp_filter.h b/libs/ardour/ardour/dsp_filter.h
index 1ffccd331982e73c2f929060967ddb934c7dd723..50fe1ff704f440c415ff6548cba8377630f8682c 100644 (file)
--- a/libs/ardour/ardour/dsp_filter.h
+++ b/libs/ardour/ardour/dsp_filter.h
@@ -23,6 +23,8 @@
 #include <string.h>
 #include <assert.h>
 #include <glib.h>
+#include <glibmm.h>
+#include <fftw3.h>
 #include "ardour/libardour_visibility.h"
 
 namespace ARDOUR { namespace DSP {
@@ -46,12 +48,13 @@ namespace ARDOUR { namespace DSP {
         */
        class DspShm {
                public:
-                       DspShm ()
+                       DspShm (size_t s = 0)
                                : _data (0)
                                , _size (0)
                        {
                                assert (sizeof(float) == sizeof (int32_t));
                                assert (sizeof(float) == sizeof (int));
+                               allocate (s);
                        }
 
                        ~DspShm () {
@@ -63,6 +66,7 @@ namespace ARDOUR { namespace DSP {
                         * @param s size, total number of float or integer elements to store.
                         */
                        void allocate (size_t s) {
+                               if (s == _size) { return; }
                                _data = realloc (_data, sizeof(float) * s);
                                if (_data) { _size = s; }
                        }
@@ -193,7 +197,7 @@ namespace ARDOUR { namespace DSP {
        };
 
        /** Biquad Filter */
-       class LIBARDOUR_API BiQuad {
+       class LIBARDOUR_API Biquad {
                public:
                        enum Type {
                                LowPass,
@@ -211,8 +215,8 @@ namespace ARDOUR { namespace DSP {
                         *
                         * @param samplerate Samplerate
                         */
-                       BiQuad (double samplerate);
-                       BiQuad (const BiQuad &other);
+                       Biquad (double samplerate);
+                       Biquad (const Biquad &other);
 
                        /** process audio data
                         *
@@ -229,9 +233,12 @@ namespace ARDOUR { namespace DSP {
                         */
                        void compute (Type t, double freq, double Q, double gain);
 
-                       /** filter transfer function (for spectrum visualization)
+                       /** setup filter, set coefficients directly */
+                       void configure (double a1, double a2, double b0, double b1, double b2);
+
+                       /** filter transfer function (filter response for spectrum visualization)
                         * @param freq frequency
-                        * @return gain at given frequency in dB
+                        * @return gain at given frequency in dB (clamped to -120..+120)
                         */
                        float dB_at_freq (float freq) const;
 
@@ -244,5 +251,51 @@ namespace ARDOUR { namespace DSP {
                        double _b0, _b1, _b2;
        };
 
+       class LIBARDOUR_API FFTSpectrum {
+               public:
+                       FFTSpectrum (uint32_t window_size, double rate);
+                       ~FFTSpectrum ();
+
+                       /** set data to be analyzed and pre-process with hanning window
+                        * n_samples + offset must not be larger than the configured window_size
+                        *
+                        * @param data raw audio data
+                        * @param n_samples number of samples to write to analysis buffer
+                        * @param offset destination offset
+                        */
+                       void set_data_hann (float const * const data, const uint32_t n_samples, const uint32_t offset = 0);
+
+                       /** process current data in buffer */
+                       void execute ();
+
+                       /** query
+                        * @param bin the frequency bin 0 .. window_size / 2
+                        * @param norm gain factor (set equal to @bin for 1/f normalization)
+                        * @return signal power at given bin (in dBFS)
+                        */
+                       float power_at_bin (const uint32_t bin, const float norm = 1.f) const;
+
+                       float freq_at_bin (const uint32_t bin) const {
+                               return bin * _fft_freq_per_bin;
+                       }
+
+               private:
+                       static Glib::Threads::Mutex fft_planner_lock;
+                       float* hann_window;
+
+                       void init (uint32_t window_size, double rate);
+                       void reset ();
+
+                       uint32_t _fft_window_size;
+                       uint32_t _fft_data_size;
+                       double   _fft_freq_per_bin;
+
+                       float* _fft_data_in;
+                       float* _fft_data_out;
+                       float* _fft_power;
+
+                       fftwf_plan _fftplan;
+       };
+
 } } /* namespace */
 #endif