Decoder FAQ
![]() | Remove Luma/Chroma artefacts |
Both options represent functions of image postprocessing. The primary purpose is to reduce block noise (when the picture gets all chunky) during playback. "Remove Luma artefacts" processes the luma data (containing information about the brightness of the picture) and improves the overall picture structure, whereas "Remove Chroma artifacts" intends to improve presentation of the color information in the picture. It is recommended to leave both options enabled always - if your computer is powerful enough. Especially processing the Luma data requires considerable processor power, so that playback on older computers or using high resolutions can lack smoothness. In such cases, you should disable these options step by step.
![]() | Mirror picture vertically |
When this option is enabled, the picture is displayed upside down.
![]() | DirectShow filter priority |
All HDX4 codecs offer a DirectShow interface. Compatible applications and players can make use of this interface to query the codec, e.g. about supported video formats. Of course, the features of the HDX4 codec can overlap those of another codec.
For encoding, this is no real problem as the codec has to be selected for encoding explicitly. For playback of videos, however, the player has to figure out which codec is the most suitable one for a given file. The higher the priority of a filter, the rather it gets selected. Set the filter priority of the HDX4 codec to High to use it for playback of compatible content.
![]() | Aspect ratio |
This option indicates if the HDX4 codec should make use of the aspect ratio information encoded in the video stream for playback. Usually, it makes sense to use the aspect ratio information of the video to avoid distorted video.


