Differences Between H.261 and MPEG-1
- H.261 only encodes video. MPEG-1 encodes video and audio.
- MPEG-1 allows arbitrary sized video (multiples of 16), but H.261 only allows 352 x 288 and half that size.
- H.261 only allows forward prediction. MPEG-1 has forward and backward prediction (B-pictures). D-pictures are also only in MPEG-1.