nuclear@0: #include <stdio.h>
nuclear@0: #include <stdint.h>
nuclear@0: #include <assert.h>
nuclear@0: #include "openal.h"
nuclear@0: #include "stream.h"
nuclear@0: #include "logger.h"
nuclear@0: #include "timer.h"
nuclear@0: #include "kiss_fft.h"
nuclear@0: 
nuclear@0: struct FFTState {
nuclear@0: 	kiss_fft_cfg kiss;
nuclear@0: 	kiss_fft_cpx *inbuf, *outbuf;
nuclear@0: 	int nsamples;
nuclear@0: };
nuclear@0: 
nuclear@0: static ALenum alformat(AudioStreamBuffer *buf)
nuclear@0: {
nuclear@0: 	return buf->channels == 1 ? AL_FORMAT_MONO16 : AL_FORMAT_STEREO16;
nuclear@0: }
nuclear@0: 
nuclear@0: AudioStream::AudioStream()
nuclear@0: {
nuclear@0: 	alsrc = 0;
nuclear@0: 	poll_interval = 25;
nuclear@0: 	done = true;
nuclear@0: 	loop = false;
nuclear@0: 	volume = 1.0;
nuclear@0: 
nuclear@0: 	freqhist = 0;
nuclear@0: 
nuclear@0: 	// by default disable FFT processing
nuclear@0: 	use_fft = false;
nuclear@0: 
nuclear@0: 	pthread_mutex_init(&mutex, 0);
nuclear@0: }
nuclear@0: 
nuclear@0: AudioStream::~AudioStream()
nuclear@0: {
nuclear@0: 	stop();
nuclear@0: }
nuclear@0: 
nuclear@0: void AudioStream::enable_fft()
nuclear@0: {
nuclear@0: 	use_fft = true;
nuclear@0: }
nuclear@0: 
nuclear@0: void AudioStream::disable_fft()
nuclear@0: {
nuclear@0: 	use_fft = false;
nuclear@0: }
nuclear@0: 
nuclear@0: bool AudioStream::is_fft_enabled() const
nuclear@0: {
nuclear@0: 	return use_fft;
nuclear@0: }
nuclear@0: 
nuclear@0: bool AudioStream::open(const char *fname)
nuclear@0: {
nuclear@0: 	return false;
nuclear@0: }
nuclear@0: 
nuclear@0: void AudioStream::close()
nuclear@0: {
nuclear@0: }
nuclear@0: 
nuclear@0: void AudioStream::set_volume(float vol)
nuclear@0: {
nuclear@0: 	volume = vol;
nuclear@0: 
nuclear@0: 	pthread_mutex_lock(&mutex);
nuclear@0: 	if(alsrc) {
nuclear@0: 		alSourcef(alsrc, AL_GAIN, vol);
nuclear@0: 	}
nuclear@0: 	pthread_mutex_unlock(&mutex);
nuclear@0: }
nuclear@0: 
nuclear@0: float AudioStream::get_volume() const
nuclear@0: {
nuclear@0: 	return volume;
nuclear@0: }
nuclear@0: 
nuclear@0: static void *thread_func(void *arg)
nuclear@0: {
nuclear@0: 	AudioStream *astr = (AudioStream*)arg;
nuclear@0: 	astr->poll_loop();
nuclear@0: 	return 0;
nuclear@0: }
nuclear@0: 
nuclear@0: void AudioStream::play(AUDIO_PLAYMODE mode)
nuclear@0: {
nuclear@0: 	loop = (mode == AUDIO_PLAYMODE_LOOP);
nuclear@0: 	done = false;
nuclear@0: 
nuclear@0: 	if(pthread_create(&play_thread, 0, thread_func, this) != 0) {
nuclear@0: 		error_log("failed to create music playback thread\n");
nuclear@0: 	}
nuclear@0: }
nuclear@0: 
nuclear@0: void AudioStream::stop()
nuclear@0: {
nuclear@0: 	pthread_mutex_lock(&mutex);
nuclear@0: 
nuclear@0: 	if(alsrc) {
nuclear@0: 		done = true;
nuclear@0: 		alSourceStop(alsrc);
nuclear@0: 		printf("waiting for the music thread to stop\n");
nuclear@0: 		pthread_mutex_unlock(&mutex);
nuclear@0: 		pthread_join(play_thread, 0);
nuclear@0: 	} else {
nuclear@0: 		pthread_mutex_unlock(&mutex);
nuclear@0: 	}
nuclear@0: }
nuclear@0: 
nuclear@0: // gets an array of buffers and returns the index of the one matching id
nuclear@0: static inline int find_buffer(unsigned int id, unsigned int *barr, int num)
nuclear@0: {
nuclear@0: 	for(int i=0; i<num; i++) {
nuclear@0: 		if(barr[i] == id) {
nuclear@0: 			return i;
nuclear@0: 		}
nuclear@0: 	}
nuclear@0: 	return -1;
nuclear@0: }
nuclear@0: 
nuclear@0: 
nuclear@0: static int queued_idx_list[AUDIO_NUM_BUFFERS];
nuclear@0: static int queued_idx_head = 0;
nuclear@0: static int queued_idx_tail = 0;
nuclear@0: 
nuclear@0: #define BUFQ_UNQUEUE() \
nuclear@0: 	do { \
nuclear@0: 		queued_idx_tail = (queued_idx_tail + 1) % AUDIO_NUM_BUFFERS; \
nuclear@0: 	} while(0)
nuclear@0: 
nuclear@0: 
nuclear@0: #define BUFQ_QUEUE(idx)	\
nuclear@0: 	do { \
nuclear@0: 		queued_idx_head = (queued_idx_head + 1) % AUDIO_NUM_BUFFERS; \
nuclear@0: 		queued_idx_list[queued_idx_head] = idx; \
nuclear@0: 	} while(0)
nuclear@0: 
nuclear@0: // thread function
nuclear@0: void AudioStream::poll_loop()
nuclear@0: {
nuclear@0: 	long prev_msec = -1000;
nuclear@0: 	unsigned int albuf[AUDIO_NUM_BUFFERS];
nuclear@0: 	int freqbins[AUDIO_NUM_BUFFERS][AUDIO_FFT_BINS];
nuclear@0: 
nuclear@0: 	pthread_mutex_lock(&mutex);
nuclear@0: 	alGenSources(1, &alsrc);
nuclear@0: 	alSourcei(alsrc, AL_LOOPING, AL_FALSE);
nuclear@0: 	alSourcef(alsrc, AL_GAIN, volume);
nuclear@0: 	alGenBuffers(AUDIO_NUM_BUFFERS, albuf);
nuclear@0: 	AudioStreamBuffer *buf = new AudioStreamBuffer;
nuclear@0: 
nuclear@0: 	FFTState fft;
nuclear@0: 	fft.kiss = kiss_fft_alloc(AUDIO_FFT_SAMPLES, 0, 0, 0);
nuclear@0: 	assert(fft.kiss);
nuclear@0: 	fft.inbuf = new kiss_fft_cpx[AUDIO_FFT_SAMPLES];
nuclear@0: 	fft.outbuf = new kiss_fft_cpx[AUDIO_FFT_SAMPLES];
nuclear@0: 	assert(fft.inbuf && fft.outbuf);
nuclear@0: 	fft.nsamples = AUDIO_FFT_SAMPLES;
nuclear@0: 
nuclear@0: 	// zero out the inbuf array to get rid of the imaginary parts
nuclear@0: 	memset(fft.inbuf, 0, AUDIO_FFT_SAMPLES * sizeof *fft.inbuf);
nuclear@0: 
nuclear@0: 	for(int i=0; i<AUDIO_NUM_BUFFERS; i++) {
nuclear@0: 		if(more_samples(buf)) {
nuclear@0: 			int bufsz = buf->num_samples * buf->channels * 2;       // 2 is for 16bit samples
nuclear@0: 			alBufferData(albuf[i], alformat(buf), buf->samples, bufsz, buf->sample_rate);
nuclear@0: 
nuclear@0: 			if(alGetError()) {
nuclear@0: 				fprintf(stderr, "failed to load sample data into OpenAL buffer\n");
nuclear@0: 			}
nuclear@0: 
nuclear@0: 			alSourceQueueBuffers(alsrc, 1, albuf + i);
nuclear@0: 			BUFQ_QUEUE(i);
nuclear@0: 
nuclear@0: 			if(alGetError()) {
nuclear@0: 				fprintf(stderr, "failed to start streaming audio buffers\n");
nuclear@0: 			}
nuclear@0: 
nuclear@0: 			// also calculate the frequencies
nuclear@0: 			calc_freq(buf, freqbins[i], &fft);
nuclear@0: 		} else {
nuclear@0: 			break;
nuclear@0: 		}
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	// start playback
nuclear@0: 	alSourcePlay(alsrc);
nuclear@0: 	while(!done) {
nuclear@0: 		// XXX this doesn't work
nuclear@0: 		/*
nuclear@0: 		// first let's figure out which buffer is currently playing
nuclear@0: 		int cur_buf;
nuclear@0: 		alGetSourcei(alsrc, AL_BUFFER, &cur_buf);
nuclear@0: 		int cur_buf_idx = find_buffer(cur_buf, albuf, AUDIO_NUM_BUFFERS);
nuclear@0: 
nuclear@0: 		// make the fft histogram pointer point to the correct frequency bin array
nuclear@0: 		freqhist = cur_buf_idx != -1 ? freqbins[cur_buf_idx] : 0;
nuclear@0: 		if(!freqhist) {
nuclear@0: 			debug_log("skata\n");
nuclear@0: 		}
nuclear@0: 		*/
nuclear@0: 
nuclear@0: 		/* find out how many (if any) of the queued buffers are
nuclear@0: 		* done, and free to be reused.
nuclear@0: 		*/
nuclear@0: 		int num_buf_done;
nuclear@0: 		alGetSourcei(alsrc, AL_BUFFERS_PROCESSED, &num_buf_done);
nuclear@0: 		for(int i=0; i<num_buf_done; i++) {
nuclear@0: 			int err;
nuclear@0: 			// unqueue a buffer...
nuclear@0: 			unsigned int buf_id;
nuclear@0: 			alSourceUnqueueBuffers(alsrc, 1, &buf_id);
nuclear@0: 
nuclear@0: 			if((err = alGetError())) {
nuclear@0: 				fprintf(stderr, "failed to unqueue used buffer (error: %x)\n", err);
nuclear@0: 				num_buf_done = i;
nuclear@0: 				break;
nuclear@0: 			}
nuclear@0: 			BUFQ_UNQUEUE();
nuclear@0: 
nuclear@0: 			// find out which one of our al buffers we just unqueued
nuclear@0: 			int bidx = find_buffer(buf_id, albuf, AUDIO_NUM_BUFFERS);
nuclear@0: 			assert(bidx != -1);
nuclear@0: 
nuclear@0: 			int looping;
nuclear@0: 
nuclear@0: 			alGetSourcei(alsrc, AL_LOOPING, &looping);
nuclear@0: 			assert(looping == AL_FALSE);
nuclear@0: 			/*if((unsigned int)cur_buf == buf_id) {
nuclear@0: 				continue;
nuclear@0: 			}*/
nuclear@0: 
nuclear@0: 			// if there are more data, fill it up and requeue it
nuclear@0: 			if(more_samples(buf)) {
nuclear@0: 				int bufsz = buf->num_samples * buf->channels * 2;       // 2 is for 16bit samples
nuclear@0: 				alBufferData(buf_id, alformat(buf), buf->samples, bufsz, buf->sample_rate);
nuclear@0: 				if((err = alGetError())) {
nuclear@0: 					fprintf(stderr, "failed to load sample data into OpenAL buffer (error: %x)\n", err);
nuclear@0: 				}
nuclear@0: 
nuclear@0: 				alSourceQueueBuffers(alsrc, 1, &buf_id);
nuclear@0: 				if(alGetError()) {
nuclear@0: 					fprintf(stderr, "failed to start streaming audio buffers\n");
nuclear@0: 				}
nuclear@0: 				BUFQ_QUEUE(bidx);
nuclear@0: 
nuclear@0: 				// also calculate the frequencies if required
nuclear@0: 				if(use_fft) {
nuclear@0: 					calc_freq(buf, freqbins[bidx], &fft);
nuclear@0: 				}
nuclear@0: 			} else {
nuclear@0: 				// no more data...
nuclear@0: 				if(loop) {
nuclear@0: 					rewind();
nuclear@0: 				} else {
nuclear@0: 					done = true;
nuclear@0: 				}
nuclear@0: 			}
nuclear@0: 		}
nuclear@0: 		if(use_fft) {
nuclear@0: 			freqhist = freqbins[queued_idx_list[queued_idx_tail]];
nuclear@0: 		}
nuclear@0: 
nuclear@0: 		if(num_buf_done) {
nuclear@0: 			// make sure playback didn't stop
nuclear@0: 			int state;
nuclear@0: 			alGetSourcei(alsrc, AL_SOURCE_STATE, &state);
nuclear@0: 			if(state != AL_PLAYING) {
nuclear@0: 				alSourcePlay(alsrc);
nuclear@0: 			}
nuclear@0: 		}
nuclear@0: 
nuclear@0: 		pthread_mutex_unlock(&mutex);
nuclear@0: 		long msec = get_time_msec();
nuclear@0: 		long dt = msec - prev_msec;
nuclear@0: 		prev_msec = msec;
nuclear@0: 
nuclear@0: 		if(dt < poll_interval - 5) {
nuclear@0: 			sleep_msec(poll_interval - dt);
nuclear@0: 		} else {
nuclear@0: 			sched_yield();
nuclear@0: 		}
nuclear@0: 		pthread_mutex_lock(&mutex);
nuclear@0: 	}
nuclear@0: 
nuclear@0: 
nuclear@0: 	// done with the data, wait for the source to stop playing before cleanup
nuclear@0: 	int state;
nuclear@0: 	while(alGetSourcei(alsrc, AL_SOURCE_STATE, &state), state == AL_PLAYING) {
nuclear@0: 		sched_yield();
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	freqhist = 0;
nuclear@0: 
nuclear@0: 	alDeleteBuffers(AUDIO_NUM_BUFFERS, albuf);
nuclear@0: 	alDeleteSources(1, &alsrc);
nuclear@0: 	alsrc = 0;
nuclear@0: 	pthread_mutex_unlock(&mutex);
nuclear@0: 
nuclear@0: 	delete buf;
nuclear@0: 
nuclear@0: 	delete [] fft.inbuf;
nuclear@0: 	delete [] fft.outbuf;
nuclear@0: 	kiss_fft_free(fft.kiss);
nuclear@0: }
nuclear@0: 
nuclear@0: int AudioStream::freq_count(int bin) const
nuclear@0: {
nuclear@0: 	if(!freqhist || !use_fft || bin < 0 || bin >= AUDIO_BUFFER_SAMPLES) {
nuclear@0: 		return 0;
nuclear@0: 	}
nuclear@0: 	return freqhist[bin];
nuclear@0: }
nuclear@0: 
nuclear@0: #define NORM_FACTOR		(1.0f / (float)AUDIO_FFT_SAMPLES)
nuclear@0: float AudioStream::freq_normalized(int bin) const
nuclear@0: {
nuclear@0: 	// TODO remove the fudge factor
nuclear@0: 	return freq_count(bin) * NORM_FACTOR * 0.25;
nuclear@0: }
nuclear@0: 
nuclear@0: // frequency range in hertz
nuclear@0: int AudioStream::freq_count(int range_start, int range_end) const
nuclear@0: {
nuclear@0: 	// NOTE this will probably be something like sampling freq / num-bins Hz per bin...
nuclear@0: 	return 0;	// TODO
nuclear@0: }
nuclear@0: 
nuclear@0: // TODO ok this might be inefficient, copying the data around a lot, optimize later
nuclear@0: void AudioStream::calc_freq(AudioStreamBuffer *buf, int *bins, FFTState *fft)
nuclear@0: {
nuclear@0: 	kiss_fft_cpx *inptr = fft->inbuf;
nuclear@0: 	int16_t *samples = (int16_t*)buf->samples;
nuclear@0: 	for(int i=0; i<AUDIO_BUFFER_SAMPLES; i++) {
nuclear@0: 
nuclear@0: 		inptr->i = 0;
nuclear@0: 		if(i < buf->num_samples) {
nuclear@0: 			int left = samples[i * 2];
nuclear@0: 			int right = samples[i * 2 + 1];
nuclear@0: 
nuclear@0: 			(inptr++)->r = (left + right) / 2;
nuclear@0: 		} else {
nuclear@0: 			(inptr++)->r = 0;
nuclear@0: 		}
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	kiss_fft(fft->kiss, fft->inbuf, fft->outbuf);
nuclear@0: 
nuclear@0: 	// then copy all the relevant data to the bins array
nuclear@0: 	int num_out_samples = AUDIO_BUFFER_SAMPLES / 2;
nuclear@0: 	int samples_per_bin = num_out_samples / AUDIO_FFT_BINS;
nuclear@0: 
nuclear@0: 	long abins[AUDIO_FFT_BINS];
nuclear@0: 
nuclear@0: 	int prev_bidx = -1;
nuclear@0: 	// ignore the DC bin (0)
nuclear@0: 	for(int i=1; i<num_out_samples; i++) {
nuclear@0: 		int bidx = i * AUDIO_FFT_BINS / num_out_samples;
nuclear@0: 		float x = fft->outbuf[i].r;
nuclear@0: 		float y = fft->outbuf[i].i;
nuclear@0: 		int val = x * x + y * y;
nuclear@0: 
nuclear@0: 		if(bidx != prev_bidx) {
nuclear@0: 			abins[bidx] = val;
nuclear@0: 			prev_bidx = bidx;
nuclear@0: 		} else {
nuclear@0: 			abins[bidx] += val;
nuclear@0: 		}
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	for(int i=0; i<AUDIO_FFT_BINS; i++) {
nuclear@0: 		long res = abins[i] / (long)samples_per_bin;
nuclear@0: 		bins[i] = res;
nuclear@0: 		assert(bins[i] == res);
nuclear@0: 	}
nuclear@0: }