Manual
Table Of Contents
- Introduction
- Supported Codecs and Formats
- The Sonnox Fraunhofer Pro-Codec
- Additional Information on Workflows
- Lossless Codecs (mp3-HD and HD-AAC)
- Description of Controls
- Presets and Project/Session Data Handling
- Preset Manager Toolbar
- Pro-Codec Signal and Control Flow Diagram
- Specifications
- Copyright and Acknowledgements
- Manual Revision History
- Platform Specific Supplement
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In this case, monitoring the lossless codec can indicate the presence of a significant
difference signal under some circumstances, but the Bitstream Level metering will read zero.
In this instance, the ‘lossless’ output will be clipping. This situation can be mitigated using
the Bitstream Level trim; of course it is always better practice to avoid an overloading input.
In contrast, a clipped wav file (recorded with overloads) will be replicated losslessly; and if
the lossy core of a lossless codec overloads from a non-overloading input, the resulting file
will also be lossless.
4.4 Bitstream Level Monitoring
Section 3.4 of this manual describes how any form of filtering can, under certain
circumstances, increase the level of the signal. If your input is hot, this can potentially
produce overloads when the signal is decoded. The section goes on to describe how the
TRIM tab can be used in real time to monitor these potential overloads, and discusses the
tools provided to alleviate the problem.
It is important to note that the indicated Bitstream metering and overload LEDs are provided
as a guide only. If a segment of audio is being cycled, these maximum values are not exactly
repeatable from one cycle to the next. Furthermore, in some host applications, repeatedly
rewinding to the beginning of the track will also not result in repeatable maximum values.
The discrepancies in both cases should be minor, and not all audio and not all codecs will
suffer this. However, it is not always possible to trim exactly while auditioning, because the
subsequent pass to online render might have a slightly different maximum value.
There is a highly technical reason for this, stemming from the difficulty of synchronizing the
start point of the buffer that is used to input data to the codecs.
In some situations this will be important and, for those occasions, we recommend using
offline encoding. Offline encoding is exactly repeatable however many times the file is
encoded (because it is a file-based process, not a stream-based process).
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