Is it really implemented ?? it seems to me that XVID_H263, XVID_CUSTOM and XVID_MPEG are ignored in the IPB encoder (encoder_encode_bframes) at least, i'm sure that there is no custom matrix support. harder to implement with bframes ? because the IPB encoder is pretty stable now, and i would like to use different quant matrix, (mpeg,h263 AND custom) Thanks in advance, MarcFD