Chebji wrote:
it would seem to only change the combing artifacts, which not all interlaced dvds show unless you pause them. if you can tell me definitely that progressive is always SHARPER, or more detailed, or better color than interlaced, then i would agree with going progressive. if it doesn't really matter other than to save space, then it doesn't seem a big deal. all the best, rana,
Hasan
1) You never see combing unless you force your system to show them. Checking Combing artifacts is just a technique people use to find out about the encoding method. What we have been calling Prog, Interlaced, Pseudo-prog, Film based, Video based etc etc, are all words of convenience and so are Combing Artifacts.
2) NTSC displays 60 images per Sec. Film has 24 frames per sec and are spread over 60 NTSC images in one Sec. As DVD info is like a Computer program, 24 film frames can be recorded in 48 half pictures and for the remaining 12 half pictures, instructions are given to DVD player to repeat the appropriate half pictures. (DVD medium could have recorded 24 full pictures per sec, but it has not been incorporated in the present standard). This is what we call Progressive (for film) and you can see it requires 48 half frames to be recorded instead of 60 half frames and hence requires 25% (or 20% depending on how you count it) less space.
3) Alternatively, the repeated half frames can actually be recorded un-necessarily. This is what we have been calling Pseudo-progressive.
4) Another method of converting 24 film frames into 60 individual video fields is just let the camera record at its pace and let the film run at its own pace. This results in multi-images in still video frames. You don’t see multi images in the moving image. This is what I call “Interlacedâ€. Actually, SHEMAROO has been advertising this to be a beneficial thing as “Smooth Motionâ€, but experts don’t agree with it.
The benefit of Progressive Film to DVD for DVD viewers is that equipment exists that can recreate the original 24 film frames at a higher resolution. Also, this is the default standard method of transferring Film on to DVD. One problem with Indian DVDs is that rarely do they treat it as Film to DVD conversion. Instead it can be NTSC master to DVD, NTSC-VHS to DVD, PAL Master to NTSC master to DVD, NTSC VHS to NTSC DVD, PAL VHS to NTSC VHS to NTSC DVD, PAL DVD to NTSC DVD, etc etc. Nothing can beat the straight from Film to DVD conversion.
If the source material (TV serials) contains 50 or 60 distinct half frames, that material has to stay that way. Here we have a certain resolution but 50 or 60 moving images.
In case of Film on DVD, why not get the extra resolution as there are only 24 moving images per sec.??
Regarding your questioning how can prog encoding improve Sharpness and PQ:
I agree, it can’t. But why we normally get better Sharpness and PQ with Prog encoding is due to the expertise of the DVD author and the right process in use for Film to DVD conversion. For those DVD authors, who are competent in Film to DVD conversion, there is no reason for them to record the extra (un-necessary) 12 half frames per sec.
Rana
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...( well i indulged in a lil bit sarcasm myself.. no offence though mate ! )
