Deinterlacing video can be a tricky situation, especially with the numerous interlacing/deinterlacing filters available in Avidemux. This guide is here to offer you some help in deciding which filters are better for you, and how you should them.

Simply put, interlacing is a technique for storing frames of video in halves split between separate images. The picture is broken into multiple lines and the odd lines go to one frame, while the even lines go to the other frame. This is called interlaced video. If you do not properly deinterlace your video, the video pictures may look weird or at worst, be broken.

Important:

• When you are deinterlacing video, the deinterlacing video filters should always go first, even before cropping filters.
• Completely disable postprocessing of Horizontal and Vertical deblocking. These should be unnecessary for your video if other filters and the video codec settings are correct.

For DVD video, a good general purpose deinterlacing filter is Decomb Telecide. You will need to select a Strategy type from the pulldown menu. Selecting “No strategy” will effectively remove any interlaced lines and result in a proper picture. This is recommended by default, other options are appropriate sometimes. See that article (or below) for more detailed information about that filter.

If the source video is 29.97(nbsp)fps (or 30(nbsp)fps), and you want to keep that framerate, then all you need to do is deinterlace the video with Decomb Telecide and nothing else.

• First add the Decomb Telecide filter.
• For the filter configuration option Strategy select No Strategy. This will only deinterlace the video and leave the framerate unaltered.
• You do not need to use Decomb Decimate because you are not trying to reduce the number of frames in the video.

If the source video is 29.97(nbsp)fps (or 30(nbsp)fps), and you want to transform it to 23.976(nbsp)fps (or 24(nbsp)fps), do the following:

• First add the Decomb Telecide filter.
• For the filter configuration option Strategy select 3:2 Pulldown. This will deinterlace the video and prepare framerate to be properly 24(nbsp)fps, but it does not actually do it.
• You must also use Decomb Decimate after the Decomb Telecide to get the proper number of frames for 24(nbsp)fps. Using the default options Decomb Decimate is normally good enough. This will reduce the number of frames in the video to approximately 24(nbsp)fps.

Deinterlacing of video internally within MythTV is not always the most effective or the highest quality choice. Sometimes it is better to leave your video recorded in non-deinterlaced form and then deinterlace it in Avidemux using a more specialized and powerful filter. The video filter Yadif with default settings works very well in most situations.