Documentation
¶
Overview ¶
Package format defines audio format types for voice processing.
Index ¶
Constants ¶
This section is empty.
Variables ¶
var ( // Twilio is Twilio's native format (mulaw 8kHz mono). Twilio = AudioFormat{Encoding: string(MuLaw), SampleRate: 8000, Channels: 1} // Telnyx is Telnyx's native format (mulaw 8kHz mono). Telnyx = AudioFormat{Encoding: string(MuLaw), SampleRate: 8000, Channels: 1} // Vonage is Vonage's native format (PCM16 16kHz mono). Vonage = AudioFormat{Encoding: string(Linear16), SampleRate: 16000, Channels: 1} // OpenAI is OpenAI Realtime's format (PCM16 24kHz mono). OpenAI = AudioFormat{Encoding: string(Linear16), SampleRate: 24000, Channels: 1} // GeminiInput is Gemini Live's input format (PCM16 16kHz mono). GeminiInput = AudioFormat{Encoding: string(Linear16), SampleRate: 16000, Channels: 1} // GeminiOutput is Gemini Live's output format (PCM16 24kHz mono). GeminiOutput = AudioFormat{Encoding: string(Linear16), SampleRate: 24000, Channels: 1} )
Common audio formats used in voice gateways.
var ( // PCM16_24kHz is PCM16 24kHz mono. PCM16_24kHz = OpenAI // PCM16_16kHz is PCM16 16kHz mono. PCM16_16kHz = GeminiInput )
Encoding-based aliases for provider-agnostic usage.
Functions ¶
func IsRawEncoding ¶ added in v0.13.0
IsRawEncoding returns true if the encoding string represents a raw audio format. This is a convenience function that normalizes the input and checks if it's raw. It handles case insensitivity, whitespace, and common aliases.
Example:
IsRawEncoding("linear16") // true
IsRawEncoding("PCM16") // true (normalized to linear16)
IsRawEncoding(" mulaw ") // true (trimmed)
IsRawEncoding("mp3") // false (container format)
Types ¶
type AudioFormat ¶
type AudioFormat struct {
// Encoding is the audio encoding (e.g., Linear16, MuLaw, ALaw).
Encoding string
// SampleRate is the sample rate in Hz (8000, 16000, 24000).
SampleRate int
// Channels is the number of audio channels (1 = mono, 2 = stereo).
Channels int
}
AudioFormat describes an audio format for conversion.
type Encoding ¶ added in v0.13.0
type Encoding string
Encoding represents an audio encoding format name.
const ( // Linear16 is 16-bit linear PCM (also called PCM16, pcm_s16le). // This is a raw format that requires explicit sample rate and channels. Linear16 Encoding = "linear16" // MuLaw is G.711 µ-law encoding (telephony standard in North America/Japan). // This is a raw format that requires explicit sample rate and channels. MuLaw Encoding = "mulaw" // ALaw is G.711 A-law encoding (telephony standard in Europe). // This is a raw format that requires explicit sample rate and channels. ALaw Encoding = "alaw" // MP3 is MPEG Audio Layer III compressed format. // This is a container format with embedded metadata. MP3 Encoding = "mp3" // Opus is the Opus compressed audio format. // This is a container format with embedded metadata. Opus Encoding = "opus" // FLAC is Free Lossless Audio Codec. // This is a container format with embedded metadata. FLAC Encoding = "flac" // AAC is Advanced Audio Coding. // This is a container format with embedded metadata. AAC Encoding = "aac" // Speex is the Speex speech codec. // Optimized for voice, used in some VoIP applications. Speex Encoding = "speex" // WebM is the WebM container format (typically contains Opus or Vorbis). // This is a container format with embedded metadata. WebM Encoding = "webm" )
Standard encoding names used across voice providers.
func (Encoding) IsRaw ¶ added in v0.13.0
IsRaw returns true if the encoding is a raw audio format without container headers. Raw formats (linear16, mulaw, alaw) require explicit sample rate and channels because the audio data contains no metadata. Container formats (mp3, opus, flac, aac, wav) include headers with metadata and can be auto-detected by audio processing services.
func (Encoding) Normalize ¶ added in v0.13.0
Normalize returns a canonical encoding name (lowercase, trimmed). This handles common variations:
- Case insensitivity: "LINEAR16" → "linear16"
- Whitespace: " mulaw " → "mulaw"
- Aliases: "pcm16" → "linear16", "ulaw" → "mulaw", "g711a" → "alaw"
- Container mappings: "wav" → "linear16" (WAV contains raw PCM)
Source Files