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Linear Acoustic APTO for OEM 

Linear Acoustic® APTO™ is a state-of-the-art loudness processing solution designed to control loudness levels of real-time audio streams or of file-based assets. Its adaptive algorithm enhances the listening experience, improves dialog intelligibility, prevents from listening annoyance and, while non affecting the original sound quality and creative intent, provides uncompromised loudness consistency with full regulatory compliance across all platforms.

Equipped with preconfigured profiles as well as opened to user customizable setting, and optionally bundled with Emmy-award winning Linear Acoustic® UPMAX® upmixing and downmixing technologies, Linear Acoustic® APTO provides the best listening experience for any type of playback environments including DVB, DTT, OTT, Radio, gaming, streaming, mobile and more. 

Next Generation Loudness Adaptation

Unlike other solutions, APTO™ architecture is based on algorithms that, relying on psychoacoustic models, properly define the ideal amount of adaptation required to fulfill the best sound experience for any listening environment.  This “no-compromise” approach, which does not involve any traditional dynamics compression technology, provides fully coherent channels, phase and mix balance, allowing the original sound program to be preserved without introducing artifacts. 

Guaranteed Loudness Compliance 

With support from mono to 7.1 audio formats, Linear Acoustic® APTO™ provides compliance with all ITU-R.BS1770-4 based international loudness recommendations including ATSC A/85, EBU R128, ARIB TR-B32, FreeTV OP59, as well as with dialog-based normalization.  
Because of its innovative approach, loudness compliance is guaranteed independently from the profile or the amount of adaptation being used.

Flexible Control

The Linear Acoustic APTO™ product line includes APTO.file™ for file-based processing and APTO.stream™ for real-time processing.  Both solutions allow the content owner, the distributor, or the broadcaster to comfortably pursue adaptation of any content, anytime, and in any operational scenario. They provide a user-selectable range of typical “listening environments” to optionally tailor the processing for a variety of applications, including broadcast, radio, gaming, mobile, streaming, home-cinema. In both the real-time and the file-based domains various loudness parameters are smoothly controlled, including Target Loudness, Dialog Loudness, Adaptation %, LRA, and True-Peak Limiting.  In addition, APTO.file™ provides Momentary Limiting, Short-Term Limiting, and Brick-Wall Limiting control. APTO.stream™ operates within a processing latency of less than 50ms.

The OEM Package 

APTO™ Processing works in head-end architectures of file-based and stream encoding as well as in playback devices with multiple platform options available.
The OEM module provides a straightforward C++ interface on Windows and Linux, using input and output sample buffers for easy integration.
Simple to integrate C++ API interface
Buffer-based audio sample interface for input and output
Independent streams processed simultaneously by multiple instances
Up to 8 channels per stream
Microsoft Windows 32 and 64-bit modules
Linux 32 and 64-bit modules
Other platforms and implementations on request


Linear Acoustic® APTO™ processing is available in Software Development Kits with implementation manuals, implementation test checklists and testing materials for requirements and recommendations, and backed by first class technical support to ensure fast, correct implementation.