PHP code example of phpmlkit / soundfile

    
        
<?php
require_once('vendor/autoload.php');

/* Start to develop here. Best regards https://php-download.com/ */

    

phpmlkit / soundfile example snippets

use function PhpMlKit\SoundFile\{sf_read, sf_write, sf_info};

// Read a file — returns [NDArray, SfInfo]
[$audio, $info] = sf_read('input.wav');
// $audio shape: [441000] (mono, Float32)

// Write it back (format and subtype auto-detected from extension)
sf_write('output.wav', $audio, $info->sampleRate);

// Probe signal properties without loading data
$info = sf_info('input.wav');
echo "{$info->frames} frames, {$info->channels} channels, {$info->duration()}s";

use function PhpMlKit\SoundFile\sf_resample;
use PhpMlKit\SoundFile\Enums\ResampleQuality;

// Chunked progressive — safe for large files (default)
$resampled = sf_resample($audio, inputRate: 44100, outputRate: 22050);

// One-shot simple — best for small signals
$resampled = sf_resample($audio, 44100, 16000, chunkSize: null);

// Best quality, explicit chunk size
$resampled = sf_resample(
    $audio, 44100, 8000,
    quality: ResampleQuality::Best,
    chunkSize: 4096,
);

use PhpMlKit\SoundFile\SoundFile;
use PhpMlKit\SoundFile\Enums\FileMode;

// Open for reading
$sf = new SoundFile('input.wav', FileMode::Read);

// Seek and read
$sf->seek(44100);
$chunk = $sf->read(512);
echo $sf->tell(); // 44612

// Iterate in blocks
foreach ($sf->blocks(1024) as $block) {
    process($block);
}
$sf->close();

// Open for writing
$out = new SoundFile('output.wav', FileMode::Write,
    sampleRate: 44100, channels: 2,
);
$out->setTitle('My Track');
$out->setArtist('My Artist');
$out->write($stereoData);
$out->close();

function sf_read(
    string $file,
    ?int $start = null,     // First frame (0-based; null = beginning)
    ?int $stop = null,      // One past last frame (null = EOF)
    bool $always2d = false, // If true, mono returns [frames, 1] instead of [frames]
    int $blocksize = 4096,  // Chunk size for internal read loop
): array // [NDArray, SfInfo]

[$data, $info] = sf_read('song.wav');
[$part, $info] = sf_read('song.wav', start: 44100, stop: 88200);
[$data, $info] = sf_read('song.wav', always2d: true);

function sf_write(
    string $file,
    NDArray $data,               // [frames] or [frames, channels]
    int $sampleRate,             // Sample rate in Hz
    ?AudioFormat $format = null, // Inferred from extension if null
    ?SampleFormat $subtype = null, // Format's default if null
): void

sf_write('out.wav', $data, sampleRate: 44100);
sf_write('out.flac', $data, 44100, subtype: SampleFormat::Pcm24);

function sf_info(string $file): SfInfo

function sf_metadata(string $file): SfMetadata

$meta = sf_metadata('song.wav');
echo $meta->artist;

function sf_check_format(AudioFormat $format, SampleFormat $subtype): bool

sf_check_format(AudioFormat::Wav, SampleFormat::Pcm16);  // true
sf_check_format(AudioFormat::Ogg, SampleFormat::Pcm16);  // false

function sf_resample(
    NDArray $input,                     // [frames, channels]
    int $inputRate,                     // Source sample rate in Hz
    int $outputRate,                    // Target sample rate in Hz
    ResampleQuality $quality = ResampleQuality::Best,
    ?int $chunkSize = 2048,             // null = one-shot, int = chunked progressive
): NDArray                                // [newFrames, channels] Float32

$resampled = sf_resample($data, 44100, 22050);           // chunked progressive
$resampled = sf_resample($data, 44100, 8000, chunkSize: null); // one-shot simple

new SoundFile(
    string $path,
    FileMode $mode = FileMode::Read,
    // Write-mode parameters:
    ?int $sampleRate = null,
    ?int $channels = null,
    ?AudioFormat $format = null,
    ?SampleFormat $subtype = null,
)

AudioFormat::Wav->extension();           // 'wav'
AudioFormat::fromExtension('flac');      // AudioFormat::Flac
AudioFormat::fromPath('song.mp3');       // AudioFormat::Mpeg
AudioFormat::Wav->defaultSampleFormat(); // SampleFormat::Pcm16
AudioFormat::Wav->compatibleSampleFormats(); // [PcmS8, Pcm16, Pcm24, ...]

SampleFormat::Pcm16->bitDepth();    // 16
SampleFormat::Pcm16->isInteger();   // true
SampleFormat::Float->isPcm();       // false
SampleFormat::Float->toDtype();     // DType::Float32