• Guillaume Desmottes's avatar
    v4l2: add alternate interlace mode · d1501f09
    Guillaume Desmottes authored
    When using this mode each frame is split in two fields, each one being
    transferred using its own buffer.
    This is implemented with the V4L2_FIELD_ALTERNATE field format in v4l2.
    
    This mode is enabled using a caps filter such as
    "v4l2src ! video/x-raw\(format:Interlaced\)"
    
    Here are the main changes related to this feature:
    
    - use the INTERLACED caps feature with this mode.
    
    - in this mode both fields of a given frame have the same sequence/offset
    so adjust the algorithm checking for lost field/frame accordingly.
    
    - double pool's min number of buffers as each frame requires 2 buffers.
    
    Fix #504Co-authored-by: Zeeshan Ali's avatarZeeshan Ali <zeenix@collabora.co.uk>
    d1501f09