NIST to SPX Converter

Convert your nist files to spx online & free

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Settings

Bitrate: Set the overall output Speex audio bitrate. Designed for human speech encoding, Speex reaches transparency at ultra-low bitrate with a maximum bitrate of 44 kbps.

Audio Channels: Set the number of audio channels. This setting is most useful when downmixing channels (e.g., from 5.1 to stereo).

Frequency: Set the sample rate of the audio. Music with a full spectrum (20 Hz — 20 kHz) requires values not lower than 44.1 kHz to achieve transparency. More info can be found on the wiki.

Convert to NIST

nist

NIST (National Institute of Standards and Technology)

SPHERE (SPeech HEader Resources) is a file format defined by NIST (National Institute of Standards and Technology) and is used with speech audio. SoX can read these files when they contain μ-law and PCM data. It will ignore any header information that says the data is compressed using shorten compression and will treat the data as either μ-law or PCM. This will allow SoX and the command line shorten program to be run together using pipes to encompasses the data and then pass the result to SoX for processing.

SPX Converter

spx

Speex

An SPX file is a Speex audio file saved within an Ogg Vorbis container. Speex is an open source patent-free audio format designed for speech compression. It supports variable bitrate (VBR) encoding and several features not found in other audio codecs. Some examples include embedded encoding, intensity stereo encoding, and voice activity detection.

How to convert NIST to SPX

Step 1

Upload nist-file(s)

Select files from Computer, Google Drive, Dropbox, URL or by dragging it on the page.

Step 2

Choose "to spx"

Choose spx or any other format you need as a result (more than 200 formats supported)

Step 3

Download your spx

Let the file convert and you can download your spx file right afterwards