I think there is a bug in umc_video_processing.cpp: line 230:
if (k == iD3DProcessing || k == iColorConv)
the iD3DProcessing field is not initialized, so this can return unexpected result.
The side effect is when doing de-interlacing and colorspace convertion in videoprocessing, this will result in an error returned and the failure of the decoding .
I found this when doing h.264 de-inerlacing to RGB32 color space.