Opale Systems MetricServer platform evolves
The latest additions and enhancements to the Opale Systems MetricServer platform bring the power of ITU POLQA, PESQ, and PEAQ standardized metrics to any organization that wants to take full control of their voice and audio quality optimization processes. Read on to learn more about automated processing using MetricServer with cross-platform application program interface (API) support.
POLQA, PESQ et PEAQ: 'Testing' vs 'Processing
When we talk about objective techniques such as POLQA, PESQ and PEAQ to assess voice and audio quality, we often think in terms of testing, i.e. using a test system of some kind. For example, the MultiDSLA system meets the requirements of a turnkey test system, i.e:
- Generating "reference" speech or music samples
- Passing these through the device or system under test
- Capturing the "degraded" speech or music
- Processing the results
Requirements of codec developers and others
The configuration we see above is a generic solution, which adapts well to many different environments and technologies, streamlines the process for the user, and offers great control. It is also an active, real-time solution, generating results every time a test is run. But especially in an all-software environment, such as in codec development and characterization for example, a user's existing configuration will often take care of steps 1 to 3 above. What that user needs is a means of post-processing existing pairs of reference and degraded recordings, usually in PCM or wave format, to provide the scores and other data provided by the chosen measure(s).
NB: In some cases, active testing with the MultiDSLA system may reveal information that is not usually available using a post-processing method. This is especially true for speech/audio delay or latency, which MultiDSLA accurately measures with synchronized nodes.
Opale Systems MetricServer platform: High processing volume
The processing volume can be high, as a thorough test of a codec may involve multiple speech or music samples, multiple real or simulated network conditions, multiple combinations of codec parameters, etc. And each time a developer changes the codec, the entire process must be repeated to determine the effect on the quality of the voice or music. MetricServer makes it possible to perform these regression tests reliably, consistently and with minimal learning curve and overhead.
Solution MetricServer by Opale Systems
Opale's MetricServer solution was developed to meet the needs of developers and QA professionals working in areas such as speech coding, speech processing, Bluetooth streaming, etc., who need to obtain scores from any of the popular metrics mentioned above. These requirements usually include the need for process automation and this has been recognized in the MetricServer concept.
Opale Systems MetricServer platform: Simple Operating Modele
MetricServer has a simple principle, based on the Input, Process, Output model. The input is a pair of reference and degraded records, the process is one or more of the metrics, including POLQA, PESQ and PEAQ; the output represents the results.
This illustration shows the concept and also shows that the inputs, processes, and outputs are each represented by one or more profiles or sets of metrics. These profiles are unlimited in number and can be combined very easily to cover all of an organization's case processing needs.
Opale Systems MetricServer platform : The best of all worlds
MetricServer supports both console-based operation and operation via a Python test script. The system consists of a core server engine, a web browser application and a comprehensive API, primarily supporting the Python scripting language. Both the web browser application and the API are clients of the server, and the standard version supports the simultaneous use of up to five client sessions, with any combination of browser application and API. The system can be expanded in blocks of five client sessions to support an entire team. The web browser application facilitates small or large-scale processing of full-fledged file pairs, and also allows MetricServer configurations to be created and validated before an automation script is used.
Expanded Python API Support
Recent additions to MetricServer include an enhanced API that includes a Python package that is compatible with 32- and 64-bit Windows, MacOS and Linux, offering great versatility and a high probability of compatibility with existing platforms.
Simple configuration and scripting
MetricServer's simple design and functional model allows users to focus on their real tasks. Initial configuration is simple and the powerful API simplifies the scripting task.
Opale Systems
Thursday, 23rd June 2022 
