Setting up enhanced VQ mode - AWS Elemental MediaLive

Setting up enhanced VQ mode

Enhanced VQ is an optional mode that affects the video quality of outputs. It affects the video encode where both of the following apply:

Enhanced VQ applies as follows:

  • It doesn't apply to Frame Capture output groups.

  • It does apply to Multiplex output groups. For this type of output group, you must enable the mode.

  • It does apply to the other types of output groups. For these types, you can optionally enable the mode.

  • It is required if you want to convert HDR color space to SDR color space in an output that uses H.264. Even if the encode uses VBR, you must enable the mode to obtain this color space conversion. For more information, see Color space handling in AWS Elemental MediaLive.

Note

If the rate control mode is VBR, there is no benefit to setting up enhanced VQ mode. But the channel would still incur the costs for enhanced VQ.

For more information about the benefits of enhanced VQ mode, see Benefits of enhanced VQ.

For information on charges for using this mode, see the MediaLive price list.

Note

This section assumes that you are familiar with creating or editing a channel, as described in Creating a channel from scratch.

The fields in the console for setting this mode are in the Codec settings section of the video Stream settings in each output. To review the step where you complete these fields, see Step 6: Set up the video encode.

To enable enhanced VQ

You can enable enhanced VQ in any video encode that uses H.264 (AVC) as the codec.

  1. In the Output groups section of the Create channel page of the MediaLive console, in the Stream settings pane, choose Video.

  2. In the Codec settings section, expand the Additional encoding settings section.

  3. For Quality level, choose ENHANCED_QUALITY.

  4. (Optional) For Filter settings, choose Temporal filter. Or to omit the filter, choose Don't include.

    For information about the benefits of filters, see Benefits of the temporal filter.

  5. If you choose Temporal, optionally change the default strength, and optionally enable sharpening. For details about a field on the MediaLive console, choose the Info link next to the field.

Benefits of enhanced VQ

When enhanced VQ is enabled, MediaLive can produce slightly better video quality without an increase in the bitrate (the bitrate fields in the Rate control section under Codec settings).

You can therefore use enhanced VQ in one of two ways:

  • You can choose to take advantage of the improved video quality. Typically, the main improvement is to smooth out complex transitions in high-motion video content.

  • You can choose to lower the bitrate (by perhaps 5%) and maintain the original target video quality. Doing so lowers the bandwidth requirements for the output.

    • To change the bitrate when the rate control mode is QVBR, change the Max bitrate.

    • To change the bitrate when the rate control mode is CBR, change the Bitrate.

Benefits of the temporal filter

The temporal filter is useful for both source content that is noisy (when it has excessive digital artifacts) and source content that is clean.

When the content is noisy, the filter cleans up the source content before the encoding phase, with these two effects:

  • It improves the output video quality because the content has been cleaned up.

  • It decreases the bandwidth because MediaLive doesn't waste bits on encoding noise.

When the content is reasonably clean, the filter tends to decrease the bitrate, especially when the rate control mode is QVBR.