Configuring quality-defined variable bitrate mode

When you use QVBR, you can specify the quality level for your output and the maximum peak bitrate. For reasonable values of those settings, the encoder chooses how many bits to use for each part of the video. When you apply the same settings to several assets, your job outputs for simpler assets (such as cartoons) have smaller file sizes than your outputs for visually complex assets (such as high-motion sports with brightly dressed crowds in the background).

This section provides information about the QVBR settings. The following table provides a set of recommended values to get started with. Specify your values for these settings when you create your outputs, as described in Tutorial: Configuring job settings. For more information about each setting, choose a topic from the list that follows the table.

With all resolutions, don't specify a value for Max average bitrate unless you need to guarantee a total file size cap. When you specify a maximum average bitrate, it reduces the benefit that QVBR provides in video quality to file size ratio. To use Max average bitrate, you have to first set Quality tuning level to Multi-pass HQ.

If you aren't using Max average bitrate, and you don't need multi-pass encoding for other reasons, set Quality tuning level to Single-pass HQ.

Setting QVBR quality tuning level

Default QVBR quality level

You can keep the QVBR quality level blank to let the encoder automatically determine the appropriate quality level based on the input video frames. When you choose the default option, the encoder produces a more consistent quality across the entire video instead of a specified target quality level. If you choose this option, you can’t maintain a differentiated quality level based on the intended viewing device (for example, large-screen TV, PC or tablet, or smartphone). The encoder determines the appropriate quality level for you, based on the characteristics of your input video, to maintain a consistent video quality.

Custom QVBR quality level

You can specify the QVBR quality level on a scale between 1 and 10. The encoder determines the right number of bits to use for each part of the video to maintain the video quality that you specify.

The best value for an output depends on how the output will be viewed. In general, set QVBR quality level as shown in the following table.

The following graph shows how changing the quality level affects the bitrate that the encoder uses for different parts of the video. While the lines for both level 7 and level 9 spike and drop in the same places, the encoder uses more bits total when the quality is set higher.