Interlacing and Macroblocking

[wulf109]

I've been encodeing a TV series from DVD,the episodes run 51 minutes,which forces me to use an average bitrate of 1950 in 2-passVBR mode.Since I'm using 720x480 resolution some slight macroblocking was ocurring,though it was invisible at normal viewing distances it was still there. I had always excepted Tmpeg's default setting of interlaced. I recently changed the advanced and video tabs to non-interlacd.
Since changeing to non-interlaced the SVCD's have a much a smoother almost film like quality. But what really confuses me is the slight macroblocking I was getting in interlaced mode is gone. The non-interlaced SVCD's show no macroblocking ever closeup.
My stupid question is can non-interlaced mode reduce macroblocking? It doesn't seem logical but I believe my eyes. One more thing,I'm encodeing directly from the vob file not frameserving.

[bbb]

Changing the video source to Non-Interlaced (Progressive) seems to have helped a lot of people get better quality. This option may resize the video more accurately than in Interlaced source mode.

I've always used Non-Interlaced source because I DO create a progressive video stream in VirtualDub and frameserve it to Tmpgenc/CCE.

In any case, if it does improve your quality, stick with it--Non-Interlaced.

[Poplar]

Is Macroblocking the right term for the artifact you are seeing? A macroblock is usually referred to as the 8x8 or 16x8 pixel matrix during encoding process. Can it be used to describe artifact? I'm not sure.

Anyhoo, I think I know what artifact you are talking about. Those pixelated blocks are crying out for more BITRATES. So be generous and give the stream more bitrates. N-Pass VBR won't do much good. I know you have to cram over 50 minutes on to one CDR, but you can't cheat on bitrates and get away with it....

Actually, you can :P to some degree. For film, you can save space and bitrates with IVTC. I found out that you can do the same with non-film stuff, if you do it correctly.

[poopyhead]

encoding your output as 23.976 fps + 3:2 pulldown should usually give you more quality over 29.97 fps + interlaced...

this is because given the same amount of bitrate....encoding 29.97 fps forces tmgpenc to allocate bitrate to more frames, meaning each frame receives less bitrate and will be of lower quality (hence, the macroblocks you see)

encoding at 23.976 fps means each frame will receieve more bitrate and be clearer (less blockiness)... since 3:2 pulldown will make the fps 29.97 during playback, playback will be just as smooth as if you encoded 29.97 fps to begin w/