Integrated Solutions

Integrate loudness normalisation in any application, server or workflow with one of our solutions.


EBU R128 loudness control of ingest and archive material is a labor intensive affair when using realtime loudness meters. Grimm Audio developed a Microsoft DirectShow™ Filter for a major Dutch commercial broadcaster. LevelShow is easily integrated in any DirectShow™ Graph. This offers very flexible programming of automatic quality control and loudness normalizing processes.

Now EBU R128 and ITU BS1770-2 compatible loudness normalization can be used in a Microsoft DirectShow™ programming environment.

The task is performed in two steps, first ‘analysis’ and next ‘adjustment’. The analysis filter returns measured loudness and other R128 descriptors. These can be used to set the adjustment filter, and they can be forwarded to a database for logging purpose or metadata level control. LevelShow can be the backbone of all your loudness normalising tasks.


    • standard Microsoft DirectShow™ archtecture
    • use unlimited instances at the same time
    • processing up to 100x real time on standard PC’s
    • measurement results available for logging


Many broadcasters have implemented loudness normalization according to EBU R128 and ATSC A/85 recommendations. Manufacturers of radio and television broadcast automation systems are now challenged to add loudness functionality to their products. Grimm Audio’s LevelAPI OEM library helps them to shorten the time to market considerably.

LevelAPI is designed to be the backbone of all your loudness normalizing tasks.

With LevelAPI, compliance to EBU R128 and ATSC A/85 can easily be achieved in all major programming environments like C/C++, Java and LUA. LevelAPI comes as a programming library in the form of a .dll (Windows) or .so (Linux) file, which can analyze and normalize audio files and streams. An automatic peak limiter of high quality helps to avoid clipping. LevelAPI offers the developer an easy integration of quality control and loudness normalizing processes. The Grimm Audio team offers support in implementing LevelAPI and gives access to its deep knowledge about loudness normalization, being led by one of the founders of the EBU R128 recommendation, Eelco Grimm.


    • loudness normalisation API
    • state of the art peak limiter
    • Windows .dll file
    • Custom build Linux .so file
    • 32 and 64 bits support
  • The libLevelAPI and the example are build on Linux Version 2.6.32-5-686 (Debian 2.6.32-35) gcc v 4.3.5 (Debian 4.3.5-4). Linux Version CentOS i386 & x64. Custom builds available.

Custom Integration

For custom solutions and integrations, please contact us.