API Reference - VOICEVOX Core for PHP

Complete reference for all classes, methods, and enums in VOICEVOX Core for PHP.

Onnxruntime

ONNX Runtime loader. This is a process-level singleton — only one instance exists per process.

Methods

Method	Description
static loadOnce(string $filename = ''): self	Loads and initializes the ONNX Runtime. On subsequent calls the argument is ignored and the existing instance is returned.
static get(): ?self	Returns the existing instance, or null if not yet initialized.
supportedDevices(): string	Returns available device information as a JSON string.
static libRecommendedVersionedFilename(): string	Returns the recommended versioned filename of the ONNX Runtime library (e.g., libvoicevox_onnxruntime.1.23.2.dylib).
static libRecommendedUnversionedFilename(): string	Returns the recommended unversioned filename of the ONNX Runtime library.
static libMinRequiredMinorVersion(): int	Returns the minimum supported ONNX Runtime 1.x minor version.
static libMaxSupportedMinorVersion(): int	Returns the maximum supported ONNX Runtime 1.x minor version.

libVersionedFilename() and libUnversionedFilename() remain as deprecated aliases.

Constants

Constant	Description
LIB_MIN_REQUIRED_MINOR_VERSION	Minimum supported ONNX Runtime 1.x minor version (17)
LIB_MAX_SUPPORTED_MINOR_VERSION	Maximum supported ONNX Runtime 1.x minor version (29)
LIB_RECOMMENDED_NAME	Recommended library base name (voicevox_onnxruntime)
LIB_RECOMMENDED_VERSION	Recommended ONNX Runtime version (1.23.2)

LIB_NAME and LIB_VERSION remain as deprecated aliases.

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OpenJtalk

Text analyzer using OpenJTalk.

Methods

Method	Description
__construct(string $openJtalkDictDir)	Initializes with the path to the OpenJTalk dictionary directory.
analyze(string $text): string	Analyzes Japanese text and returns an accent phrase array as a JSON string.
useUserDict(UserDict $userDict): void	Applies a user dictionary. Call again if the dictionary is updated.

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VoiceModelFile

Voice model file (.vvm file).

Methods

Method	Description
static open(string $path): self	Opens a .vvm file.
id(): string	Returns the voice model ID as a hex string (16 bytes).
createMetasJson(): string	Returns speaker metadata as a JSON string.
close(): void	Closes the file and releases resources.

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Synthesizer

Main class for text-to-speech synthesis.

Methods

Method	Description
__construct(Onnxruntime $onnxruntime, OpenJtalk $openJtalk, AccelerationMode $accelerationMode = Auto, int $cpuNumThreads = 0)	Initializes the synthesizer.
onnxruntime(): Onnxruntime	Returns the Onnxruntime instance held by this synthesizer.
isGpuMode(): bool	Returns whether GPU mode is enabled.
metas(): string	Returns metadata for all loaded speakers as a JSON string.
loadVoiceModel(VoiceModelFile $model, OnExistingVoiceModelId $onExisting = Error): void	Loads a voice model. Use $onExisting to choose what happens when a model with the same ID is already loaded.
unloadVoiceModel(string $voiceModelId): void	Unloads a voice model by its hex ID.
isLoadedVoiceModel(string $voiceModelId): bool	Returns whether a voice model is loaded.
createAudioQuery(string $text, int $styleId): string	Generates an AudioQuery JSON from Japanese text.
createAudioQueryFromKana(string $kana, int $styleId): string	Generates an AudioQuery JSON from AquesTalk-style kana notation.
createAccentPhrases(string $text, int $styleId): string	Generates an accent phrase array JSON from Japanese text.
createAccentPhrasesFromKana(string $kana, int $styleId): string	Generates an accent phrase array JSON from kana notation.
replaceMoraData(string $accentPhrasesJson, int $styleId): string	Returns updated accent phrases with mora pitch and phoneme length from another style.
replacePhonemeLength(string $accentPhrasesJson, int $styleId): string	Returns updated accent phrases with phoneme lengths from another style.
replaceMoraPitch(string $accentPhrasesJson, int $styleId): string	Returns updated accent phrases with mora pitch from another style.
synthesis(string $audioQueryJson, int $styleId, bool $enableInterrogativeUpspeak = true): string	Synthesizes speech from an AudioQuery JSON. Returns WAV binary.
createAudioFeature(string $audioQueryJson, int $styleId, bool $enableInterrogativeUpspeak = true): AudioFeature	Creates the AudioFeature intermediate representation used for frame-based rendering.
tts(string $text, int $styleId, bool $enableInterrogativeUpspeak = true): string	Synthesizes speech from Japanese text in one step. Returns WAV binary.
ttsFromKana(string $kana, int $styleId, bool $enableInterrogativeUpspeak = true): string	Synthesizes speech from kana notation. Returns WAV binary.
createSingFrameAudioQuery(string $scoreJson, int $styleId): string	Generates a singing synthesis query JSON from a score JSON.
frameSynthesis(string $frameAudioQueryJson, int $styleId): string	Synthesizes singing audio from a frame audio query. Returns WAV binary.
createSingFrameF0(string $scoreJson, string $frameAudioQueryJson, int $styleId): string	Generates per-frame F0 (fundamental frequency) values as a JSON float array.
createSingFrameVolume(string $scoreJson, string $frameAudioQueryJson, int $styleId): string	Generates per-frame volume values as a JSON float array.

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AudioFeature and AudioFeatureSlice

AudioFeature owns the native intermediate representation, and each AudioFeatureSlice keeps its owning AudioFeature alive. Rendering is synchronous and returns raw 16-bit PCM bytes.

Class / method	Description
AudioFeature::length(): int	Returns the total number of frames.
AudioFeature::isEmpty(): bool	Returns whether the feature has no frames.
AudioFeature::whole(): AudioFeatureSlice	Returns a slice covering the whole feature.
AudioFeature::slice(int $startInclusive, int $end, bool $endIsInclusive = false, bool $clamp = false, bool $allowStartExceedsEnd = false): AudioFeatureSlice	Creates a frame-range slice. The end is exclusive by default.
AudioFeature::render(): string	Renders the whole feature as PCM.
AudioFeatureSlice::length(): int	Returns the number of frames in the slice.
AudioFeatureSlice::isEmpty(): bool	Returns whether the slice has no frames.
AudioFeatureSlice::slice(int $startInclusive, int $end, bool $endIsInclusive = false, bool $clamp = false, bool $allowStartExceedsEnd = false): AudioFeatureSlice	Creates a subslice using the same range options.
AudioFeatureSlice::render(): string	Renders the slice as PCM.

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VoicevoxCore

Global utility functions for VOICEVOX Core.

Methods

Method	Description
getVersion(): string	Returns the VOICEVOX Core version as a SemVer string.
getFrameRate(): float	Returns the number of audio frames per second (93.75 in CORE 0.17.1).
audioQueryFrameLength(string $audioQueryJson, bool $enableInterrogativeUpspeak = true): int	Returns the estimated audio length in frames.
audioQueryCreateFromAccentPhrases(string $accentPhrasesJson): string	Generates an AudioQuery JSON from an accent phrase array JSON.
audioQueryValidate(string $audioQueryJson): void	Validates an AudioQuery JSON. Throws VoicevoxException if invalid.
accentPhraseValidate(string $accentPhraseJson): void	Validates an AccentPhrase JSON. Throws VoicevoxException if invalid.
moraValidate(string $moraJson): void	Validates a Mora JSON. Throws VoicevoxException if invalid.
scoreValidate(string $scoreJson): void	Validates a Score JSON. Throws VoicevoxException if invalid.
noteValidate(string $noteJson): void	Validates a Note JSON. Throws VoicevoxException if invalid.
frameAudioQueryValidate(string $frameAudioQueryJson): void	Validates a FrameAudioQuery JSON. Throws VoicevoxException if invalid.
framePhonemeValidate(string $framePhonemeJson): void	Validates a FramePhoneme JSON. Throws VoicevoxException if invalid.
ensureCompatible(string $scoreJson, string $frameAudioQueryJson): void	Checks that a score and frame audio query are compatible. Throws VoicevoxException if not.

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UserDict

User dictionary for registering custom word pronunciations.

Methods

Method	Description
__construct()	Creates an empty user dictionary.
load(string $path): void	Loads a user dictionary from a file.
save(string $path): void	Saves the user dictionary to a file.
addWord(string $surface, string $pronunciation, int $accentType, UserDictWordType $wordType = CommonNoun, int $priority = 5): string	Adds a word and returns its UUID as a hex string.
updateWord(string $wordUuid, string $surface, string $pronunciation, int $accentType, UserDictWordType $wordType = CommonNoun, int $priority = 5): void	Updates an existing word identified by UUID.
removeWord(string $wordUuid): void	Removes the word identified by UUID.
importDict(UserDict $other): void	Imports words from another UserDict.
toJson(): string	Returns all words as a JSON string.

$priority must be between 0 and 10. Values outside that range throw an InvalidArgumentException.

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Enum: AccelerationMode

Hardware acceleration mode for the synthesizer.

Case	Value	Description
Auto	0	Automatically selects the best available mode.
Cpu	1	Forces CPU mode.
Gpu	2	Forces GPU mode.

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Enum: OnExistingVoiceModelId

Behavior of Synthesizer::loadVoiceModel() when a voice model with the same ID is already loaded.

Case	Value	Description
Error	0	Throws an error. This is the default.
Reload	1	Reloads the existing voice model.
Skip	2	Does nothing.

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Enum: UserDictWordType

Part-of-speech for user dictionary entries.

Case	Value	Description
ProperNoun	0	Proper noun
CommonNoun	1	Common noun
Verb	2	Verb
Adjective	3	Adjective
Suffix	4	Suffix

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VoicevoxException

Thrown when the VOICEVOX Core C API call returns an error code. The exception message contains the error description from the library.