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julius-speech/julius: Release 4.5

Akinobu Lee; Tatsuya Kawahara

What's new in Julius-4.5 Improved VAD

A WebRTC-based voice activity detection (VAD) was introduced to improve voice detection:

Now Julius has two VAD modules: old module (input level and zero-cross based) and the new module (libfvad = model based). Both of them runs concurrently in parallel for an audio input. When the new module is enabled, Julius will detect speech trigger only if both of them outputs speech flag.

Use -fvad option to enable. See Release.txt or julius/ how to use it.

DNN-HMM CPU multi-threading

DNN-HMM computation now supports CPU multi-threading. Multi-threading may speed up DNN-HMM computation to some extent. The number of threads can be specified by num_threads in dnnconf. This feature is enabled by default, and the default number of threads is 2.

XML special character escape on module mode output

Notice for module-mode users: in order to make module output XML-compliant, the XML special characters are now escaped, ex. '>' to '>'. A backward-compat option -noxmlescape is available to inhibit the new escaping feature and go back to the same behavior as previous versions.

Moving to UTF-8

We have moved to UTF-8. The codes and documents in master branch has been unified to UTF-8 encoding.

For backward compatibility and make log tracking easy, the recent release codes with old encoding is kept at branch "master-4.5-legacy". If you want to see the code before the release of 4.5 (2019/1/2) in old encoding, please checkout the kept branch.


We are moving from text file to markdown for easier update. Currently available ones are:

Others will come soon.

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