source for softclip~. this shows how to pass the object structure “x” into the audio perform function.<\/p>\n
#include \"m_pd.h\"\r\n#include \r\n#include \r\n#ifdef NT\r\n#pragma warning( disable : 4244 )\r\n#pragma warning( disable : 4305 )\r\n#endif\r\n\r\n\/* ------------------------ softclip~ ----------------------------- *\/\r\n\r\n\/* tilde object to do a simple soft clipping algorithm. *\/\r\n\r\nstatic t_class *softclip_class;\r\n\r\ntypedef struct _softclip\r\n{\r\n t_object x_obj; \t\/* obligatory header *\/\r\n t_float gain; \t\/* floats on the first inlet set the gain *\/\r\n\tt_float sample_rate;\r\n t_float freq;\r\n} t_softclip;\r\n\r\n \/* this is the actual performance routine which acts on the samples.\r\n It's called with a single pointer \"w\" which is our location in the\r\n DSP call list. We return a new \"w\" which will point to the next item\r\n after us. Meanwhile, w[0] is just a pointer to dsp-perform itself\r\n (no use to us), w[1] and w[2] are the input and output vector locations,\r\n and w[3] is the number of points to calculate. *\/\r\nstatic t_int *softclip_perform(t_int *w)\r\n{\r\n\tt_softclip *x = (t_softclip *)(w[1]);\r\n t_float *in = (t_float *)(w[2]);\r\n t_float *out = (t_float *)(w[3]);\r\n int n = (int)(w[4]);\r\n\r\n\t\/\/ i like counting from zero, so i use samplenumber to count the offset from\r\n\t\/\/ the start of the in and out blocks\r\n\tint samplenumber = 0;\r\n\tfloat a = -0.5f;\r\n\tfloat b = 0.0;\r\n\tfloat c = 1.5f;\r\n\tfloat d = 0.0;\r\n\tfloat ingain;\r\n\r\n while (n--)\r\n {\r\n\t\tingain = x->gain * *(in+samplenumber);\r\n\t\tif(ingain > 1)\r\n\t\t\t*(out+samplenumber) = 1.0f;\r\n\t\telse if(ingain < -1) \t\t\t*(out+samplenumber) = -1.0f; \t\telse \t\t\t*(out+samplenumber) = a * ingain * ingain * ingain \t\t\t\t\t\t\t+ b * ingain * ingain \t\t\t\t\t\t\t+ c * ingain \t\t\t\t\t\t\t+ d; \t\tsamplenumber++; } return (w+5); } \/* called to start DSP. Here we call Pd back to add our perform routine to a linear callback list which Pd in turn calls to grind out the samples. *\/ static void softclip_dsp(t_softclip *x, t_signal **sp) { \tx->sample_rate = sp[0]->s_sr;\r\n dsp_add(softclip_perform, 4, x, sp[0]->s_vec, sp[1]->s_vec, sp[0]->s_n);\r\n}\r\n\r\nstatic void *softclip_new(void)\r\n{\r\n t_softclip *x = (t_softclip *)pd_new(softclip_class);\r\n x->freq = 432.0f;\r\n outlet_new(&x->x_obj, gensym(\"signal\"));\r\n return (x);\r\n}\r\n\r\n \/* this routine, which must have exactly this name (with the \"~\" replaced\r\n by \"_tilde) is called when the code is first loaded, and tells Pd how\r\n to build the \"class\". *\/\r\nvoid softclip_tilde_setup(void)\r\n{\r\n softclip_class = class_new(gensym(\"softclip~\"), (t_newmethod)softclip_new, 0,\r\n \tsizeof(t_softclip), 0, A_DEFFLOAT, 0);\r\n\t\r\n\t\/* this is magic to declare that the leftmost, \"main\" inlet\r\n\t takes signals; other signal inlets are done differently... *\/\r\n\t\/* also installs gain as the leftmost inlet float *\/\r\n CLASS_MAINSIGNALIN(softclip_class, t_softclip, gain);\r\n\t\r\n\t\/* here we tell Pd about the \"dsp\" method, which is called back\r\n\twhen DSP is turned on. *\/\r\n class_addmethod(softclip_class, (t_method)softclip_dsp, gensym(\"dsp\"), (t_atomtype)0);\r\n}\r\n<\/pre>\nsource for rms~. this shows how to allocate and deallocate an array<\/p>\n
\r\n#include \"m_pd.h\"\r\n#include \r\n#include \r\n#ifdef NT\r\n#pragma warning( disable : 4244 )\r\n#pragma warning( disable : 4305 )\r\n#endif\r\n\r\n\/* ------------------------ rms~ ----------------------------- *\/\r\n\r\n\/* tilde object to take the absolute value of a signal at audio rate *\/\r\n\/* an argument for window size may be entered upon instantiation *\/\r\n\r\nstatic t_class *rms_class;\r\n\r\ntypedef struct _rms\r\n{\r\n t_object x_obj;\t\t\t\/\/ obligatory variable\r\n t_float x_f;\t\t\t\/\/ stores message recieved on audio inlet\r\n\tt_int window;\t\t\t\/\/ window size set by object argument\r\n\tt_float sum;\t\t\t\/\/ running sum of squared values\r\n\tt_float *squaretab;\t\t\/\/ table to hold squared values\r\n\tt_int tabread1;\t\t\t\/\/ pointer offset for newest table value\r\n\tt_int tabread2;\t\t\t\/\/ pointer offset for oldest table value\r\n} t_rms;\r\n\r\nstatic t_int *rms_perform(t_int *w)\r\n{\r\n\tt_rms *x = (t_rms *)(w[1]);\r\n t_float *in = (t_float *)(w[2]);\r\n t_float *out = (t_float *)(w[3]);\r\n int n = (int)(w[4]);\r\n\r\n\t\/\/ number of samples passed\r\n\tint blocksize = n;\r\n\t\/\/ sample from 0 up\r\n\tint sample = 0;\r\n\t\/\/ mean of squared value\r\n\tfloat mean = 0;\r\n\t\/\/ used to multiply instead of divide\r\n\tfloat oneOverWindow = 1.0f\/x->window;\r\n\r\n while (n--)\r\n {\r\n\t\t\/\/ store newest squared value in the table\r\n \t*(x->squaretab+x->tabread1) = *(in+sample) * *(in+sample);\r\n\t\t\/\/ add this value to the running sum\r\n\t\tx->sum += *(x->squaretab+x->tabread1);\r\n\t\t\/\/ subtract the oldest value in the table\r\n\t\tx->sum -= *(x->squaretab+x->tabread2);\r\n\r\n\t\t\/\/ compute the current mean value\r\n \tmean = x->sum * oneOverWindow;\r\n\r\n\t\t\/\/ take the square root and send the value to outlet\r\n \r\n \t*(out+sample) = sqrt(mean);\r\n\t\t\/\/ increment to next sample\r\n\t\tsample++;\r\n\t\t\/\/ increment to next table position\r\n x->tabread1++;\r\n x->tabread2++;\r\n\t\t\/\/ reset to beginning of table\r\n\t\tif(x->tabread1 >= x->window)\r\n\t\t\tx->tabread1 = 0;\r\n\t\t\/\/ increment to next table position\r\n \t\t\/\/ reset to beginning of table\r\n\t\tif(x->tabread2 >= x->window)\r\n\t\t\tx->tabread2 = 0;\r\n }\r\n return (w+5);\r\n}\r\n\r\nstatic void rms_dsp(t_rms *x, t_signal **sp)\r\n{\r\n dsp_add(rms_perform, 4, x, sp[0]->s_vec, sp[1]->s_vec, sp[0]->s_n);\r\n}\r\n\r\n\/\/ setting window size\r\nvoid rms_windowset(t_rms *x, t_floatarg f)\r\n{\r\n\t\/\/ using a good value\r\n\tif( f >= 256 && f <= 4096 )\r\n\t\tx->window = f;\r\n\t\/\/ blocking bad values\r\n\telse if( f < 256 )\r\n\t{\r\n\t\tx->window = 256;\r\n\t\tpost(\"rms~: window size must be set to a value between 256 and 4096\");\r\n\t}\r\n\telse if( f > 4096 )\r\n\t{\r\n\t\tx->window = 4096;\r\n\t\tpost(\"rms~: window size must be set to a value between 256 and 4096\");\r\n\t}\r\n}\r\n\r\nstatic void *rms_new(t_floatarg f)\r\n{\r\n\tint i;\r\n\t\r\n t_rms *x = (t_rms *)pd_new(rms_class);\r\n outlet_new(&x->x_obj, gensym(\"signal\"));\r\n\tx->squaretab = 0;\r\n x->x_f = 0;\r\n\t\/\/ initialize the sum\r\n\tx->sum = 0;\r\n\t\/\/ changing windowsize on creation\r\n\trms_windowset(x, f);\r\n\t\/\/ intializing table for largest window size\r\n x->squaretab = (t_float *)malloc(4097 * sizeof(t_float));\r\n\t\/\/ initialzing the table to 0\r\n\tfor( i = 0; i < x->window; i++)\r\n\t\t*(x->squaretab+i) = 0;\r\n\t\/\/ initializing newest sample\r\n\tx->tabread1 = 0;\r\n\t\/\/ initializing oldest sample\r\n\tx->tabread2 = 1;\r\n\r\n return (x);\r\n}\r\n\r\n\/\/ function to clear the allocated square table\r\nstatic void rms_free(t_rms *x)\r\n{\r\n free(x->squaretab);\r\n\tif(x->squaretab != 0)\r\n\t{\r\n\t\tfree(x->squaretab);\r\n\t\tx->squaretab = 0;\r\n\t}\r\n}\r\n\r\nvoid rms_tilde_setup(void)\r\n{\r\n rms_class = class_new(gensym(\"rms~\"), (t_newmethod)rms_new, (t_method)rms_free,\r\n \tsizeof(t_rms), 0, A_DEFFLOAT, 0);\r\n CLASS_MAINSIGNALIN(rms_class, t_rms, x_f);\r\n class_addmethod(rms_class, (t_method)rms_dsp, gensym(\"dsp\"), (t_atomtype)0);\r\n}\r\n<\/pre>\n","protected":false},"excerpt":{"rendered":"source for softclip~. this shows how to pass the object structure “x” into the audio perform function. #include “m_pd.h” #include #include #ifdef NT #pragma warning( disable : 4244 ) #pragma warning( disable : 4305 ) #endif \/* ———————— softclip~ —————————– … Continue reading