85 lines
2.7 KiB
C++
85 lines
2.7 KiB
C++
//
|
|
// Created by david on 01.02.2026.
|
|
//
|
|
|
|
#define LOG_TAG "PlaybackEngine"
|
|
|
|
#include "PlaybackEngine.h"
|
|
#include "logging.h"
|
|
#include "mpg123.h"
|
|
#include "mp3file.h"
|
|
#include <vector>
|
|
|
|
/**
|
|
* Read samples from the next mp3-frame into the struct MP3File's buffer.
|
|
* @return number of samples read (uses buffer_size which is much smaller than total length)
|
|
*/
|
|
static inline int readBuffer2(MP3File* mp3)
|
|
{
|
|
size_t done = 0;
|
|
int err = mpg123_read(mp3->handle, mp3->buffer, mp3->buffer_size, &done);
|
|
mp3->remaining_samples -= done / sizeof(int16_t);
|
|
mp3->offset = 0;
|
|
if (err != MPG123_OK && err != MPG123_DONE) LOGE("mpg123_read() err=%d done=%d", err, done);
|
|
if(err == MPG123_DONE) return done / sizeof(int16_t);
|
|
return err != MPG123_OK ? 0 : done / sizeof(int16_t);
|
|
}
|
|
|
|
static bool read_mp3(std::string filename, std::vector<float>& samples) {
|
|
// TODO: assumes 48000 Hz sampling rate of the file
|
|
// note: our resource file is mono (1 channel = 1 samples_per_frame)!
|
|
MP3File *mFile = mp3file_open(filename.c_str(), 0); // MPG123_ENC_FLOAT_32 (but does not seem to work)
|
|
memset(mFile->buffer, 0, mFile->buffer_size);
|
|
bool ok1 = mFile != nullptr;
|
|
int ok2 = true;
|
|
int i = 0;
|
|
if(ok1) {
|
|
samples.resize(mFile->num_samples);
|
|
while (ok2 && mFile->remaining_samples > 0) {
|
|
ok2 = readBuffer2(mFile);
|
|
if (!ok2) break;
|
|
for (int j = 0; j < ok2 && i < mFile->num_samples; j++, i++) {
|
|
int16_t *src = ((int16_t *) mFile->buffer) + j;
|
|
samples[i] = (*src) / 32768.0f;
|
|
}
|
|
}
|
|
}
|
|
if(!ok2) {
|
|
LOGI("ok2=false at i=%d", i);
|
|
}
|
|
if(mFile)
|
|
mp3file_delete(mFile);
|
|
return ok1 && ok2;
|
|
}
|
|
|
|
PlaybackEngine::PlaybackEngine(std::string filesDir, int resid): mFilesDir(filesDir) {
|
|
LOGI("PlaybackEngine()");
|
|
LOGI("NDK LOG_LEVEL=%d", LOG_LEVEL);
|
|
// NDK LOG_LEVEL=3 (DEBUG)
|
|
std::vector<float> samples;
|
|
bool is_ok = read_mp3(mFilesDir + "/" + std::to_string(resid) + ".mp3", samples);
|
|
LOGI("read_mp3() is_ok=%d", is_ok);
|
|
mPlayer = new MixingPlayer(samples);
|
|
int32_t res = mPlayer->startAudio();
|
|
LOGI("startAudio() = %d", res);
|
|
}
|
|
|
|
PlaybackEngine::~PlaybackEngine() {
|
|
LOGI("~PlaybackEngine()");
|
|
mPlayer->stopAudio();
|
|
delete mPlayer;
|
|
mPlayer = nullptr;
|
|
}
|
|
|
|
void PlaybackEngine::playBeat() {
|
|
if(mPlayer) mPlayer->setStartBeat();
|
|
}
|
|
|
|
void PlaybackEngine::playMusic(int fd) {
|
|
//if(mPlayer) mPlayer->playMusic();
|
|
// TODO: fd is opened; dispose of fd when stopping or being discarded ...
|
|
LOGI("PlaybackEngine::playMusic(fd=%d)", fd);
|
|
close(fd); // for now, nothing is implemented. we just close it again.
|
|
// we will use mp3file_open_fd() later.
|
|
}
|