FAB Subtitler can open many types of video files for preparation of subtitles: MPEG1, MPEG2, Quicktime MOV, MXF, WMV and some other. However some features like frame accurate positioning, navigation within the video file or playing the file with double speed may not work correctly in all video file formats which can be opened by FAB Subtitler.
Frame accurate positioning, navigation and playing the file with double speed will mostly work correctly when using one of the following file formats:
- MOV/MP4 with H.264 video codec
The reason for this is that FAB has developed support for the above file formats which is included in FAB Subtitler and this makes sure that such video files are played correctly. FAB Subtitler is using 3rd party DirectShow components for opening other types of video files and therefore not all functionality may work correctly with other types of video files.
Positioning in the video file may work slow if the time between I-Frames or GOPs is long. This is described in the following page:
Therefore it is recommended to use short GOP / I-Frame distances of a few frames in all video file formats because this will make the navigation in the file in FAB Subtitler very fast.
If you experience problems with a certain video file, then please convert it to one of the above video file formats with a short GOP / I-Frame distance of just a few frames and then you will be able to use it efficiently in FAB Subtitler for preparation of subtitles.