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Ocean Systems Service Offerings
VDR Noise Reduction
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| A Voyage Data
Recorder's Audio recording often contains background
ambient noise as well as engine noises, resulting un-intelligible voice
communications during playback or needed in an incident investigation. Besides the ambient noise, sometimes the
noise are introduced by the compression methods used in order to
reduce the size of capsule memory requirements. While IEC
specification requires the bridge and VHF communication to be recorded
as they were from the microphones and radios, OSI provides a service to
remove/reduce the noise from the recording so that human voice
communication can be heard. Audio Noise reduction/enhancement is carried out by using sophisticated software to remove the characteristic frequencies of the ambient noise. Special filters have been developed for typical interior bridge environment as well as exterior wings where wind noise are predominant. Bias can also be applied to adjust the level of certain frequency bands, thereby increasing the clarity of human voice with less background noise. The process starts by first converting compressed audio files into 16 bit 13 KHz WAV format. Different filters are then applied to see if noise can be cleaned and human voice amplified second by second. It is labor intensive and requires a great deal of expertise in audio engineering. However, the end results often provide a crucial piece of missing information needed for complete incident investigations. .For further inquiries, click here for company contact information.
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Click to play recording with noise
Click to play recording after noise has been removed
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