Noise reduction

Description

You can apply the noise reducer preprocessor to improve output video quality.

• The Filter parameter has four options:

  • Mean / Gaussian / Lanczos: All of these algorithms allow for varying blur strengths. Mean is the strongest filter; it operates on a smaller group of pixels. Lanczos is the mildest filter; it operates on a larger group of pixels.

  • Sharpen: This algorithm sharpens the edges instead of softening them.

  • Conserve: This algorithm limits the pixel values to within the minimum and maximum values of the neighboring pixel values. It is designed to reduce speckle noise. This filter does not seem to be very valuable with video.

  • Bilateral: This algorithm tends to preserve strong edges; it's the best compromise between noise reduction and visual quality.

• Strength: The strength parameter of the filtering has its greatest effect at 3.

Recommendations

In most cases, the noise reducer is not required. The reducer can help output quality if the content is being heavily compressed. However, it changes the visual quality of the video.

The recommended algorithm is bilateral, but the other algorithms might produce better results in certain use cases. We recommend that you run tests on a video sample, to determine the best option for your application.

Location of parameters

This table shows where the parameters mentioned in this section are located. The first column shows the location on the web interface. The second column shows the location in the event XML.

Location of parameter on web interface	Location of tag in XML
Streams > Advanced >Preprocessors > Noise Reducer > Filter	stream_assembly/video_description/video_preprocessors/ noise_reducer/filter
Streams > Advanced >Preprocessors > Noise Reducer > Strength	stream_assembly/video_description/video_preprocessors/ noise_reducer/strength