Video - Telecine Filter Tutorial
If you have progressive scan source content with a frame rate of either 23.976 or 24, and you need to produce output video at 29.97fps with telecine (aka 3:2 pulldown) applied, then this filter will provide the means to achieve that objective. The process performs the frame rate conversion resulting in a visually smooth playback result. Legacy televisions in North America were designed to display video at 29.97fps, but most film content was captured at 24fps, so the telecine process was used to transfer film-based content to videotape. The telecine process results in video that has 3 solid frames followed by 2 interlaced frames. This 3:2 cadence can be seen if you step frame-by-frame through content that had telecine applied.
More information can be found here: Telecine: 2:3 pulldown
Sample Usage
The example json below is the transcode task’s video section of a job set to convert a source video at 23.976fps progressive to an output at 29.97fps interlaced with telecine pulldown applied. Two important target video parameters that should be defined when the telecine filter is used are:
"frame_rate": "29.97""interlace_mode" : "tff"(top field first - most common) or"bff"(bottom field first)
{
"video": {
"codec": "mpeg2",
"width": 720,
"height": 480,
"bitrate_kb": 3180,
"frame_rate": 29.97,
"interlace_mode": "tff",
"filters": [
{
"kind": "telecine",
"payload": {
"interlace_mode": "tff",
"pattern": "23"
}
}
]
}
}
The interlace_mode settings in both the video section and the telecine filter should always match. The most common pattern used in telecine is 2:3, indicated in the telecine filter as “23”. The pattern options in Hybrik are:
"23""22""2332""222222222223"