diff options
Diffstat (limited to 'libaf/af_pan.c')
-rw-r--r-- | libaf/af_pan.c | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/libaf/af_pan.c b/libaf/af_pan.c new file mode 100644 index 0000000000..49e9e4cb2e --- /dev/null +++ b/libaf/af_pan.c @@ -0,0 +1,184 @@ +/*============================================================================= +// +// This software has been released under the terms of the GNU Public +// license. See http://www.gnu.org/copyleft/gpl.html for details. +// +// Copyright 2002 Anders Johansson ajh@atri.curtin.edu.au +// +//============================================================================= +*/ + +/* */ + +#include <stdio.h> +#include <stdlib.h> + +#include <unistd.h> +#include <inttypes.h> +#include <math.h> +#include <limits.h> + +#include "af.h" + +// Data for specific instances of this filter +typedef struct af_pan_s +{ + float level[AF_NCH][AF_NCH]; // Gain level for each channel +}af_pan_t; + +// Initialization and runtime control +static int control(struct af_instance_s* af, int cmd, void* arg) +{ + af_pan_t* s = af->setup; + + switch(cmd){ + case AF_CONTROL_REINIT: + // Sanity check + if(!arg) return AF_ERROR; + + af->data->rate = ((af_data_t*)arg)->rate; + af->data->format = AF_FORMAT_F | AF_FORMAT_NE; + af->data->bps = 4; + af->mul.n = af->data->nch; + af->mul.d = ((af_data_t*)arg)->nch; + + if((af->data->format != ((af_data_t*)arg)->format) || + (af->data->bps != ((af_data_t*)arg)->bps)){ + ((af_data_t*)arg)->format = af->data->format; + ((af_data_t*)arg)->bps = af->data->bps; + return AF_FALSE; + } + return control(af,AF_CONTROL_PAN_NOUT | AF_CONTROL_SET, &af->data->nch); + case AF_CONTROL_COMMAND_LINE:{ + int nch = 0; + int n = 0; + char* cp = NULL; + int j,k; + // Read number of outputs + sscanf((char*)arg,"%i%n", &nch,&n); + if(AF_OK != control(af,AF_CONTROL_PAN_NOUT | AF_CONTROL_SET, &nch)) + return AF_ERROR; + + // Read pan values + cp = &((char*)arg)[n]; + j = 0; k = 0; + while((*cp == ':') && (k < AF_NCH)){ + sscanf(cp, ":%f%n" , &s->level[k][j], &n); + s->level[k][j] = clamp(s->level[k][j],0.0,1.0); + af_msg(AF_MSG_VERBOSE,"[pan] Pan level from channel %i to" + " channel %i = %f\n",j,k,s->level[k][j]); + cp =&cp[n]; + j++; + if(j>=nch){ + j = 0; + k++; + } + } + return AF_OK; + } + case AF_CONTROL_PAN_LEVEL | AF_CONTROL_SET:{ + int i; + int ch = ((af_control_ext_t*)arg)->ch; + float* level = ((af_control_ext_t*)arg)->arg; + for(i=0;i<AF_NCH;i++) + s->level[ch][i] = clamp(level[i],0.0,1.0); + return AF_OK; + } + case AF_CONTROL_PAN_LEVEL | AF_CONTROL_GET:{ + int i; + int ch = ((af_control_ext_t*)arg)->ch; + float* level = ((af_control_ext_t*)arg)->arg; + for(i=0;i<AF_NCH;i++) + level[i] = s->level[ch][i]; + return AF_OK; + } + case AF_CONTROL_PAN_NOUT | AF_CONTROL_SET: + // Reinit must be called after this function has been called + + // Sanity check + if(((int*)arg)[0] <= 0 || ((int*)arg)[0] > 6){ + af_msg(AF_MSG_ERROR,"[pan] The number of output channels must be" + " between 1 and %i. Current value is %i\n",AF_NCH,((int*)arg)[0]); + return AF_ERROR; + } + af->data->nch=((int*)arg)[0]; + return AF_OK; + case AF_CONTROL_PAN_NOUT | AF_CONTROL_GET: + *(int*)arg = af->data->nch; + return AF_OK; + } + return AF_UNKNOWN; +} + +// Deallocate memory +static void uninit(struct af_instance_s* af) +{ + if(af->data) + free(af->data); + if(af->setup) + free(af->setup); +} + +// Filter data through filter +static af_data_t* play(struct af_instance_s* af, af_data_t* data) +{ + af_data_t* c = data; // Current working data + af_data_t* l = af->data; // Local data + af_pan_t* s = af->setup; // Setup for this instance + float* in = c->audio; // Input audio data + float* out = NULL; // Output audio data + float* end = in+c->len/4; // End of loop + int nchi = c->nch; // Number of input channels + int ncho = l->nch; // Number of output channels + register int j,k; + + if(AF_OK != RESIZE_LOCAL_BUFFER(af,data)) + return NULL; + + out = l->audio; + // Execute panning + // FIXME: Too slow + while(in < end){ + for(j=0;j<ncho;j++){ + register float x = 0.0; + register float* tin = in; + for(k=0;k<nchi;k++) + x += tin[k] * s->level[j][k]; + out[j] = x; + } + out+= ncho; + in+= nchi; + } + + // Set output data + c->audio = l->audio; + c->len = (c->len*af->mul.n)/af->mul.d; + c->nch = l->nch; + + return c; +} + +// Allocate memory and set function pointers +static int open(af_instance_t* af){ + af->control=control; + af->uninit=uninit; + af->play=play; + af->mul.n=1; + af->mul.d=1; + af->data=calloc(1,sizeof(af_data_t)); + af->setup=calloc(1,sizeof(af_pan_t)); + if(af->data == NULL || af->setup == NULL) + return AF_ERROR; + // Set initial pan to pass-through. + return AF_OK; +} + +// Description of this filter +af_info_t af_info_pan = { + "Panning audio filter", + "pan", + "Anders", + "", + AF_FLAGS_NOT_REENTRANT, + open +}; |