Interlaced or Non-Interlaced in TMPEncgreenspun.com : LUSENET : Video CD : One Thread
What is the difference between Interlaced and Non-Interlaced (progressive) mpegs, when use Tsunami Mpeg Encoder.
I mean apart from the obvious being the different way the picture is drawn. Is there an advantage to using one or the other, is there any reason why you cant make a vcd using either
-- Batfink (email@example.com), December 12, 2001
Interlace should only be used when encoding at SVCD or DVD resolutions (ie 480x576, 720x576 etc). Anything shot on film will use progressive frames. Anything shot with a video camera uses interlaced frames.
As far as using interlace on a VCD, not possible. This is the reason DVD was created, so you could have interlaced frames in an MPEG stream. VCD uses a vertical resolution of 288 lines for PAL and 240 lines for NTSC. Interlaced footage uses 576 for PAL and 480 for NTSC.
If you use interlaced mode on a motion picture, then you are wasting time as it has to encode each frame twice (once for the odd fields (1,3,5,7...) and once for the even fields(2,4,6,8...)).
Encoders however should automatically detect if the source video contains genuine interlaced frames. BBmpeg does but not sure about TMPEnc.
-- Andrew (firstname.lastname@example.org), December 12, 2001.
Ok, Thanks, Since it always defaults to progressive, i should just leave it there. What about with a dvd source though, I've noticed that when i rip a dvd, its format is usually PAL 4:3 interlaced. Should i then choose interlaced in tmpenc
-- Batfink (email@example.com), December 13, 2001.
Once again, choose interlaced if you're encoding into an SVCD or DVD format, or an AVI format which you will be outputting to tape again. For VCD or anything with a vertical resolution below 480 or 576, don't bother.
The format (ie interlaced, progressive) of the DVD is just a parameter defined in one of the IFO file (I think). You can pretty much ignore what it tells you in that respect. Have fun
-- Andrew (firstname.lastname@example.org), December 13, 2001.
There is one very important parameter that should never be overlooked here and that is field order. In TMPGenc, double-click deinterlace and choose even-odd field (field). Advance the video by clicking the right arrow. If it progresses smoothly leave the field order as is but if it judders change the field order, ie if field A (or top) now choose B (or bottom). The only exception to field importance is when ripping off film-sourced PAL DVDs to VCD: 24fps film is speeded up 4% to 25fps, so one film frame corresponds squarely to one video frame. Both fields are therefore part of the same image, unlike with film- sourced NTSC material (2:3 pulldown) or outright legitimate video from your camcorder PAL or NTSC.
-- Mehmet Tekdemir (email@example.com), December 19, 2001.