1 field is stored in one buffer,
GST_VIDEO_BUFFER_FLAG_TF
or GST_VIDEO_BUFFER_FLAG_BF
indicates if
the buffer is carrying the top or bottom field, respectively. The top and
bottom buffers must alternate in the pipeline, with this mode
(Since: 1.16).
2 fields are stored in one buffer, use the frame ID to get access to the required field. For multiview (the 'views' property > 1) the fields of view N can be found at frame ID (N * 2) and (N * 2) + 1. Each field has only half the amount of lines as noted in the height property. This mode requires multiple GstVideoMeta metadata to describe the fields.
2 fields are interleaved in one video frame. Extra buffer flags describe the field order.
frames contains both interlaced and progressive video, the buffer flags describe the frame and fields.
all frames are progressive
The possible values of the #GstVideoInterlaceMode describing the interlace mode of the stream.