Read an audio file into an AsspDataObj

Unified audio reader. Tries the ASSP C-level reader first (fastest, supports WAV, AU, NIST, SSFF and other native formats). Falls back to the av package for any format av/FFmpeg can decode (MP3, MP4, FLAC, OGG, etc.).

Usage

read_audio(fname, begin = 0, end = 0, samples = FALSE)

Arguments

fname

Path to the audio or SSFF file.

begin

Start of region to read. Default 0 = file start. In seconds (default) or samples (when samples = TRUE).

end

End of region to read. Default 0 = file end. In seconds or samples.

samples

Logical. If TRUE, begin and end are interpreted as sample indices.

Value

An AsspDataObj containing one audio track (n_samples x n_channels, INT16) plus the standard sample-rate metadata. Attributes include sampleRate, startTime, startRecord, endRecord, trackFormats and filePath. Frame rate equals the audio sample rate; one record per audio sample.

Details

For variable-rate encoded formats (e.g. MP3) with samples = TRUE, sample positions are approximated via the nominal sample rate reported by the container.

See also

read_ssff for SSFF-only files; read_jstf for JSTF files.

Examples

if (FALSE) { # \dontrun{
# Read entire WAV file
wav <- system.file("samples", "sustained", "a1.wav", package = "superassp")
au  <- read_audio(wav)

# Read a 1-second window starting at 0.5 s
clip <- read_audio(wav, begin = 0.5, end = 1.5)

# Read by sample index
first_1k <- read_audio(wav, begin = 1, end = 1000, samples = TRUE)

# MP3/MP4 fall back to FFmpeg automatically
# mp3 <- read_audio("recording.mp3")
} # }