Interlace Flicker Reduction

Graham S wrote on 4/25/2011, 4:33 AM

I would like to make a DVD using DVDAS4.5. The size of the MPEG video file is 4.2Gb which should fit onto a single layer disc. However, if I select ‘Interlace Flicker Reduction’ to ‘On’, the programme tells me that in excess of 7Gb disc space is required and that the original MPEG video file will be compressed. Forgive me if this is a naïve question and if it has been asked before, but does a video file with interlace flicker reduction activated require more disc space than would otherwise be the case? Any advice on this matter would be greatly appreciated.

Comments

Steve Grisetti wrote on 4/25/2011, 5:32 AM

It probably has more to do with formats, Graham. MPEGs can vary wildly in size, since there are so many methods and compression levels possible with them.

The wisest thing would be to create your optimized MPEG in Vegas Movie Studio and then use the option to Make Movie/Burn to Disc to export it to DVD Architect Studio. As long as the video is less than 70 minutes or so long, it's the most efficient way to deliver the file to DVDAS.

Graham S wrote on 4/26/2011, 11:07 AM

Hello Steve,

Many thanks for your reply to my original post.

What totally baffles me is why DVDAS4.5 is increasing the size of the MPEG file when I select ‘Interlace Flicker Reduction’ to ‘On’. The file is one that has been created using Canopus Procoder Express. I have used this programme to covert an original MPEG file in PAL format to NTSC. I am resident in the UK, hence the PAL format, and I wanted to send a DVD of the video to my brother who lives in Canada, hence the NTSC format.

If I have ‘Interlace Flicker Reduction’ to ‘Off’ then the size of the file stays at 4.2Gb. However, if I have ‘Interlace Flicker Reduction’ to ‘On’ then the programme treats the file size as over 7Gb and it wants to compress it so that it will fit onto a single layer DVD.

Totally confused but nevertheless with my best regards,

Graham

PeterDuke wrote on 4/26/2011, 6:30 PM

If you are converting from PAL to NTSC then certain compromises are inevitable. I would do the conversion in a good video editing program, such as Vegas, rather than DVDA which is primarily an authoring program.

In fact a good rule of thumb is to only feed DVDA elemental video and audio streams that it accepts without recompression. These streams are listed in the manual.

Jack S wrote on 4/28/2011, 10:07 AM

Graham,
I, like you, live in the UK and regularly send DVDs over to my son in the US. I have found that if you import your PAL source file into VMS10HD and 'Render As' NTSC DVD format you will be, as I was, pleasantly surprised at the result. The classic jerkiness created when you convert from 25fps to 29.97fps is virtually non-existant. Plus, you don't need to worry about interlacing. Be prepared for a long render time though.
Jack

Graham S wrote on 5/9/2011, 6:23 AM

Hello Peter and Jack,

Thank you for your replies to my post.

I believe I have cured the problem of the interlace flicker. I am now converting the PAL video to NTSC in Canopus Procoder Express using the non interlaced option. Before, it was using the default option of lower field first. I now seem to be rid of interlace flicker, you know, those partially ghosted images.

However, when playing the resultant DVD in NTSC format on my TV I am getting a slight jerkiness in moving images. It is not bad but noticeable knowing that it is not there on the PAL original. Do you know if this jerkiness is present only because I am playing a DVD in NTSC format on a PAL TV here in the UK or will that jerkiness be present when my brother plays the DVD on dedicated NTSC equipment in Canada?

All the best,

Graham

BlackMax wrote on 5/9/2011, 7:42 AM

Just FYI it seems this particular option has nothing to do with your video? From the Help:

Turn flicker reduction on when using still images that contain thin horizontal lines.

Graham S wrote on 5/9/2011, 10:59 AM

Hello BlackMax,

Thank you for that information. OK, so the interlace flicker reduction option is nothing to do with video but intended to be used with still images which contain as you say thin horizontal lines. I assume the intention is to reduce or eliminate that strobing effect you sometimes see on TV when someone is wearing a striped item of clothing.

As for the NTSC DVD that I have made using a converted PAL video file, I will send it to my brother who lives in Canada to see if he gets the same jerkiness on moving images. It’s only very slight but it’s there. Maybe this is all to do with the different frame rates of PAL (25fps), NTSC (29.97fps) and the Hz rates between UK and North American AV equipment. I am hoping that there will no such problems when the DVD is played by my brother in Canada.

All the best,

Graham

BlackMax wrote on 5/9/2011, 11:14 AM

>still images which contain as you say thin horizontal lines

No, I only showed you the Help file. In any case "flicker" is different from "jerkiness" so I don't think it is your problem.

What does DVDA tell you about the Canopus file when you go to Insert Media and select it (dimensions and fps)?

In any case sending it to yr brother is the easiest way to proceed.

Graham S wrote on 5/9/2011, 1:29 PM

Hello BlackMax,

When I import the video in DVDAS it tells me that the video is 720x480x32 at 29.97fps with audio at 48KHz.

As you say, it seems the best way to proceed is to send this DVD in NTSC format to my brother to see how it actually plays there in Canada. I am hoping that there will not be a problem and that this is a compatibility issue with my equipment here in the UK. Actually, he is coming to the UK to see me in a few weeks time and I will give the DVD to him then for him to take back.

Thank you for your interest and suggestions. It’s been great chatting with you.

All the best,

Graham

BlackMax wrote on 5/9/2011, 2:03 PM

>the video is 720x480x32 at 29.97fps

Well you should be golden then I believe, provided your Project Properties were properly set i.e. no further conversion was done! I'm no expert on PAL vs. NTSC but would expect a 29.97 DVD to look lousy on your system!

In fact I only commented here because "Reduce interlace flicker" was something that caught my eye recently but turned-out to be irrelevant to me (and for you too I think) given it was for still images only according to Sony.

But now we want you to send the disc to your brother to find-out if it works! ;-)