codecs: h264decoder: Add support for field-pair input frame

    codecs: h264picture: Count only complete complementary field pair for dpb fullness decision

    Our DPB implementation was designed as such that allowing
    temporary DPB overflow in the middle of field picture decoding
    and incomplete field pair should not trigger DPB bumping.

    codecs: h264decoder: Add support for field-pair input frame

    In case that upstream pushed buffer as a frame unit, not picture
    unit for interlaced stream, baseclass should be able to detect
    AU boundary (i.e., complementary field pair).

    codecs: h264decoder: Remove unused private variables

    ... and reset() method to clear internal status at one place

tested with d3d11 and va, including fluster test suites.

assigned to @gstreamer-merge-bot

mentioned in commit seungha.yang/gst-plugins-bad@e14bbd7f

mentioned in commit seungha.yang/gst-plugins-bad@6366435e

mentioned in commit seungha.yang/gst-plugins-bad@ae7c20a6

added 3 commits

• 6366435e - codecs: h264decoder: Remove unused private variables
• e14bbd7f - codecs: h264decoder: Add support for field-pair input frame
• ae7c20a6 - codecs: h264picture: Count only complete complementary field pair for dpb fullness decision

Compare with previous version

merged

changed milestone to %1.19.1