I am fairly experienced with IPP's codecs and modifying the code to suit my own requirements. After seeing your posts about the alignment and the 3:2 pulldown, I believe I can help you. You can contact me at jere AT dragonglobal DOT biz.
nPitchLuma = align_value
LUMA_PADDING is 0 and DATA_ALIGN is 64.
nPitchLuma is later affected to the m_pitch_luma of a H264DecoderFrame, which is used to initialize the pitch of the luma plane of the output VideoData.
T align_value(size_t nValue, size_t lAlignValue = DEFAULT_ALIGN_VALUE)
~(lAlignValue - 1));
Well, simple enough, it rounds nValue to the nearest bigger multiple of lAlignValue (provided it is a power of two).