WavePlayer audio effects
Fork of wave_player by
wave_player.cpp
- Committer:
- ballaw
- Date:
- 2014-11-18
- Revision:
- 2:32da40a33717
- Parent:
- 0:62c18ade9a60
- Child:
- 3:06bc8350c139
File content as of revision 2:32da40a33717:
//----------------------------------------------------------------------------- // a sample mbed library to play back wave files. // // explanation of wave file format. // https://ccrma.stanford.edu/courses/422/projects/WaveFormat/ // if VERBOSE is uncommented then the wave player will enter a verbose // mode that displays all data values as it reads them from the file // and writes them to the DAC. Very slow and unusable output on the DAC, // but useful for debugging wave files that don't work. //#define VERBOSE #include <mbed.h> #include <math.h> #include <stdio.h> #include <wave_player.h> #include <shared.h> Wiistate wiistate = Nothing; float vol = 0; //VOLUME FLOAT Mutex key; //----------------------------------------------------------------------------- // constructor -- accepts an mbed pin to use for AnalogOut. Only p18 will work wave_player::wave_player(AnalogOut *_dac) { wave_DAC=_dac; wave_DAC->write_u16(32768); //DAC is 0-3.3V, so idles at ~1.6V verbosity=0; } //----------------------------------------------------------------------------- // if verbosity is set then wave player enters a mode where the wave file // is decoded and displayed to the screen, including sample values put into // the DAC FIFO, and values read out of the DAC FIFO by the ISR. The DAC output // itself is so slow as to be unusable, but this might be handy for debugging // wave files that don't play //----------------------------------------------------------------------------- void wave_player::set_verbosity(int v) { verbosity=v; } int do_vol = 0; int do_flange = 1; int do_bit_crush = 0; int do_delay = 1; void update_state() { Wiistate cur_state; key.lock(); cur_state = wiistate; key.unlock(); if(cur_state == Left) { do_vol = 1; do_flange = 1; do_bit_crush = 0; do_delay = 0; } else if(cur_state == Right) { do_vol = 1; do_flange = 0; do_bit_crush = 1; do_delay = 0; } else if(cur_state == Up) { do_vol = 1; do_flange = 0; do_bit_crush = 0; do_delay = 1; } else if(cur_state == Down) { do_vol = 1; do_flange = 1; do_bit_crush = 0; do_delay = 1; } else if(cur_state == Nothing) { do_vol = 0; do_flange = 0; do_bit_crush = 0; do_delay = 0; //printf("%d %d %d %d\r\n", do_vol, do_flange, do_bit_crush, do_delay); //printf("%d %d %d %d %d %d\r\n", cur_state==Nothing, Left, Right,Up,Down, Nothing); } //printf("%d %d %d %d\r\n", do_vol, do_flange, do_bit_crush, do_delay); } //----------------------------------------------------------------------------- // player function. Takes a pointer to an opened wave file. The file needs // to be stored in a filesystem with enough bandwidth to feed the wave data. // LocalFileSystem isn't, but the SDcard is, at least for 22kHz files. The // SDcard filesystem can be hotrodded by increasing the SPI frequency it uses // internally. //----------------------------------------------------------------------------- void wave_player::play(FILE *wavefile) { unsigned chunk_id,chunk_size,channel; unsigned data,samp_int,i; short unsigned dac_data; long long slice_value; char *slice_buf; short *data_sptr; unsigned char *data_bptr; int *data_wptr; FMT_STRUCT wav_format; long slice,num_slices; DAC_wptr=0; DAC_rptr=0; for (i=0;i<256;i+=2) { DAC_fifo[i]=0; DAC_fifo[i+1]=3000; } DAC_wptr=4; DAC_on=0; fread(&chunk_id,4,1,wavefile); fread(&chunk_size,4,1,wavefile); //// #define SAMPLE_RATE 11025 #define D_SIZE 8000 #define M_PI 3.14159265358979323846 short unsigned delayed[D_SIZE]; unsigned int d_rptr = 0; unsigned int d_wptr = D_SIZE-1000;//((float)D_SIZE)/2.0; unsigned int d_wptr_2 = D_SIZE-3000; int flange = 0; // CHANG int flange_amplitude = D_SIZE/4; // /2 //int flange_freq = SAMPLE_RATE; // 2*pi*cur_samp_cnt/11025 float cur_samp_cnt = 0; int flange_r_ptr = 0; int flange_dir = 1; int flip_sec = 0; //// for(int di = 0; di < D_SIZE; di++) { delayed[di] = 0; } while (!feof(wavefile)) { if (verbosity) printf("Read chunk ID 0x%x, size 0x%x\r\n",chunk_id,chunk_size); switch (chunk_id) { case 0x46464952: fread(&data,4,1,wavefile); if (verbosity) { printf("RIFF chunk\r\n"); printf(" chunk size %d (0x%x)\r\n",chunk_size,chunk_size); printf(" RIFF type 0x%x\r\n",data); } break; case 0x20746d66: fread(&wav_format,sizeof(wav_format),1,wavefile); if (verbosity) { printf("FORMAT chunk\r\n"); printf(" chunk size %d (0x%x)\r\n",chunk_size,chunk_size); printf(" compression code %d\r\n",wav_format.comp_code); printf(" %d channels\r\n",wav_format.num_channels); printf(" %d samples/sec\r\n",wav_format.sample_rate); printf(" %d bytes/sec\r\n",wav_format.avg_Bps); printf(" block align %d\r\n",wav_format.block_align); printf(" %d bits per sample\r\n",wav_format.sig_bps); } if (chunk_size > sizeof(wav_format)) fseek(wavefile,chunk_size-sizeof(wav_format),SEEK_CUR); break; case 0x61746164: // allocate a buffer big enough to hold a slice slice_buf=(char *)malloc(wav_format.block_align); if (!slice_buf) { printf("Unable to malloc slice buffer"); exit(1); } num_slices=chunk_size/wav_format.block_align; samp_int=1000000/(wav_format.sample_rate); if (verbosity) { printf("DATA chunk\r\n"); printf(" chunk size %d (0x%x)\r\n",chunk_size,chunk_size); printf(" %d slices\r\n",num_slices); printf(" Ideal sample interval=%d\r\n",(unsigned)(1000000.0/wav_format.sample_rate)); printf(" programmed interrupt tick interval=%d\r\n",samp_int); } // starting up ticker to write samples out -- no printfs until tick.detach is called if (verbosity) tick.attach_us(this,&wave_player::dac_out, 500000); else tick.attach_us(this,&wave_player::dac_out, samp_int); DAC_on=1; // start reading slices, which contain one sample each for however many channels // are in the wave file. one channel=mono, two channels=stereo, etc. Since // mbed only has a single AnalogOut, all of the channels present are averaged // to produce a single sample value. This summing and averaging happens in // a variable of type signed long long, to make sure that the data doesn't // overflow regardless of sample size (8 bits, 16 bits, 32 bits). // // note that from what I can find that 8 bit wave files use unsigned data, // while 16 and 32 bit wave files use signed data // for (slice=0;slice<num_slices;slice+=1) { fread(slice_buf,wav_format.block_align,1,wavefile); if (feof(wavefile)) { printf("Oops -- not enough slices in the wave file\r\n"); exit(1); } data_sptr=(short *)slice_buf; // 16 bit samples data_bptr=(unsigned char *)slice_buf; // 8 bit samples data_wptr=(int *)slice_buf; // 32 bit samples slice_value=0; for (channel=0;channel<wav_format.num_channels;channel++) { switch (wav_format.sig_bps) { case 16: if (verbosity) printf("16 bit channel %d data=%d ",channel,data_sptr[channel]); slice_value+=data_sptr[channel]; break; case 32: if (verbosity) printf("32 bit channel %d data=%d ",channel,data_wptr[channel]); slice_value+=data_wptr[channel]; break; case 8: if (verbosity) printf("8 bit channel %d data=%d ",channel,(int)data_bptr[channel]); slice_value+=data_bptr[channel]; break; } } slice_value/=wav_format.num_channels; // slice_value is now averaged. Next it needs to be scaled to an unsigned 16 bit value // with DC offset so it can be written to the DAC. switch (wav_format.sig_bps) { case 8: slice_value<<=8; break; case 16: slice_value+=32768; break; case 32: slice_value>>=16; slice_value+=32768; break; } dac_data=(short unsigned)slice_value; if (verbosity) printf("sample %d wptr %d slice_value %d dac_data %u\r\n",slice,DAC_wptr,(int)slice_value,dac_data); update_state(); //// delayed[d_rptr] = dac_data; d_rptr = (d_rptr == (D_SIZE-1)) ? 0 : (d_rptr + 1); d_wptr = (d_wptr == (D_SIZE-1)) ? 0 : (d_wptr + 1); d_wptr_2 = (d_wptr_2 == (D_SIZE-1)) ? 0 : (d_wptr_2 + 1); float f_dac_data = (float)dac_data; float f_delay_data; float f_delay_data_2; int flange_dist = 0; int flange_dist_check; if(flange) { flange_dist = flange_amplitude*sin(2*M_PI*cur_samp_cnt/(float)SAMPLE_RATE); /*if(cur_samp_cnt != 0) { while(cur_samp_cnt < 4000) { flange_dist = flange_amplitude*sin(2*M_PI*cur_samp_cnt/(float)SAMPLE_RATE); printf("%f %f\r\n", flange_dist, 2*M_PI*cur_samp_cnt/(float)SAMPLE_RATE); cur_samp_cnt++; } return; }*/ //printf("%d\r\n",flange_dist); flange_dist_check = d_wptr + flange_dist - D_SIZE; //d_wptr += flange_dist_check > 0 ? flange_dist_check : (d_wptr + flange_dist) < 0 ? (D_SIZE + d_wptr + flange_dist) : flange_dist; //d_wptr += flange_dist_check < 0 ? flange_dist : ((d_wptr + flange_dist) < 0) ? 0 : flange_dist; d_wptr = ((d_wptr + flange_dist) > 0) ? (d_wptr + flange_dist) % D_SIZE : (D_SIZE + flange_dist); //(D_SIZE + flange_dist) WRONG } //cur_samp_cnt = (cur_samp_cnt+1) > SAMPLE_RATE ? 0 : (cur_samp_cnt+1); cur_samp_cnt = (cur_samp_cnt+1) > SAMPLE_RATE ? 0 : (cur_samp_cnt+1); if(cur_samp_cnt == 0) { flip_sec = !flip_sec; } #define N_SAMPLES_FLANGE_PERIOD 100//((SAMPLE_RATE) >> 2) // WHY IS MZ 100??? if(do_flange) {// && (flip_sec)) { if(flange_r_ptr == N_SAMPLES_FLANGE_PERIOD) { flange_dir = -1; } else if(flange_r_ptr == -N_SAMPLES_FLANGE_PERIOD) { flange_dir = 1; } flange_r_ptr += flange_dir; } else { flange_r_ptr = 0; } int total_ptr = (d_wptr + flange_r_ptr); total_ptr = (total_ptr > D_SIZE) ? (total_ptr - D_SIZE) : total_ptr; total_ptr = (total_ptr < 0) ? (D_SIZE - total_ptr) : total_ptr; //f_delay_data = (float) delayed[d_wptr]; f_delay_data = (float) delayed[total_ptr]; f_delay_data_2 = (float) delayed[d_wptr_2]; float f_mix; if(do_delay || do_flange) { if(do_flange) { f_mix = 0.01*f_dac_data + 0.7*f_delay_data; } else { f_mix = 0.333*f_dac_data + 0.333*f_delay_data + 0.333*f_delay_data_2; } //0.01*f_dac_data + 0.7*f_delay_data; } else { f_mix = f_dac_data; } //// float time_in_period = (float)cur_samp_cnt/(float)SAMPLE_RATE; //float vol = 0.5 + 0.5*sin(2*M_PI*time_in_period); // Full dynamic range float my_vol = 0.75 + 0.25*sin(2*M_PI*time_in_period); if(do_vol) f_mix = (my_vol*f_mix); if(do_bit_crush) { short unsigned beef = (short unsigned)f_mix; //beef = (beef>>7) << 7; //printf("beef %x\r\nbeeeef %x\r\n", beef, beef & 0xFFF0); DAC_fifo[DAC_wptr]=beef &0xF800; } else { DAC_fifo[DAC_wptr]=(short unsigned)(f_mix); } DAC_wptr=(DAC_wptr+1) & 0xff; while (DAC_wptr==DAC_rptr) { } } DAC_on=0; tick.detach(); free(slice_buf); break; case 0x5453494c: if (verbosity) printf("INFO chunk, size %d\r\n",chunk_size); fseek(wavefile,chunk_size,SEEK_CUR); break; default: printf("unknown chunk type 0x%x, size %d\r\n",chunk_id,chunk_size); data=fseek(wavefile,chunk_size,SEEK_CUR); break; } fread(&chunk_id,4,1,wavefile); fread(&chunk_size,4,1,wavefile); } } void wave_player::dac_out() { if (DAC_on) { #ifdef VERBOSE printf("ISR rdptr %d got %u\r\n",DAC_rptr,DAC_fifo[DAC_rptr]); #endif wave_DAC->write_u16(DAC_fifo[DAC_rptr]); DAC_rptr=(DAC_rptr+1) & 0xff; } }