problem with downscaling fullHD to dvd

[Randall Leong]

Originally Posted by Jeff Harper

Stanley, your are using an odd size, it cannot look right. 720x480 is not a suggestion, it is the dimensions it needs to be to play properly on a TV.

You avoid recompressing by rendering to a format that DVDA can use, which is mpeg 2. Please read DVDA help for more information, this is explained clearly there, then come back and let us know what is happening.

Therein lies another problem:

VirtualDub does not preserve pixel aspect ratios when resizing. Instead, it converts everything to square pixels. As a result, the resulting 720x480 downconversion is detected by Vegas as a squeezed 4:3 aspect ratio, which is far from widescreen. Vegas (and all other NLEs) must get tricked to see that video as a widescreen 16:9 video. And Vegas detects that video as LFF even though the actual field order is UFF. (Or, if you're using Adobe Premiere, that VirtualDub 720x480 video is detected as progressive-scan video even though it's actually interlaced.)

[Gerald Webb]

Originally Posted by John Peterson

DVD Architect will re-compress that video. So if you don't like the compression algorithm it uses, you are out of luck quality wise.

John

Yes, but Lagarith is a visually lossless codec, so you are carrying the best quality you can all the way through to the final mpeg2 compression.
You can't want for any better than that unless you just burn a DVD data disc with uncompressed AVI. You wont fit much on though :)

[Dale Guthormsen]

After going through the hd sd thing, and once again reading all the prior posts in this thread,

Boy am I glad i made the decision to only produce high definition.

If some one wants me to do something in Sd I shoot them on my not so old cameras!!!

with blu ray players costing all of 70 dollars now, why bother if you have HD!!

I will also charge more for DVD's than I do for blu rays!!!

[Stanley Szpala]

Originally Posted by Jeff Harper

Stanley, your are using an odd size, it cannot look right. 720x480 is not a suggestion, it is the dimensions it needs to be to play properly on a TV.

You avoid recompressing by rendering to a format that DVDA can use, which is mpeg 2. Please read DVDA help for more information, this is explained clearly there, then come back and let us know what is happening.

I looked into the help file, but I didn't find any obvious mistake I was making.
The bottom line for me is that both mpeg2 and avi standard definition look great when viewed in the native resolution, i.e. in a section of the full screen 1920x1080. Unfortunately only sd avi looks good in full screen mode. I'm not sure why only avi? Is it something with the upscaling algorithm?
Thanks.

[Jeff Harper]

type in mpeg 2 and you'll find the specs

[Jerry Amende]

I made the following "quick & dirty" tutorial to prepare AVCHD 1920x1080 60i for DVD Architect. Most of the time it works great for me. I the resultant SD mpg contains excessive moire or flickering, an intermediate render may be required.

YouTube - Vegas Pro 9.0e Quick & Dirty AVCHD to SD Tutorial

Good Luck!
...Jerry

PS: New to this forum - still need to learn how to embed video clips.

[Stanley Szpala]

Jerry, FYI: when you start reading previous posts about this issue, you'll see that Vegas does NOT do a great job in converting to SD. Lanczos algorithm is usually preferred, and this may be done in VirtualDub.
Good luck.

[Jerry Amende]

Originally Posted by Stanley Szpala

Jerry, FYI: when you start reading previous posts about this issue, you'll see that Vegas does NOT do a great job in converting to SD. Lanczos algorithm is usually preferred, and this may be done in VirtualDub.
Good luck.

Stanley, I agree 1000%. And I've read much about this subject and done hours & hours of trial runs.

The procedure I posted in my tutorial is labeled "Quick and Dirty" because that's what it is. I've found that for the most part, this procedure creates "pretty darn good" quality SD for DVDA prep - obviously not perfect. I would like to get feedback (often times 'cuz it works for me, it may not work for others).

Sometimes, using the procedure listed above, the output quality will just be lame, many times evidenced in excessive moire and/or flicker. In those cases, more stringent methods must be taken - for example intermediate renders & downsizing using other tools.

...Jerry

PS: One slight error in the tut - I mentioned Project settings should be set to "Interpolate for fast motion, Blend for slow motion" - I've since found out that advice is only true for Progressive renders. The important thing is Deinterlace is NOT set to "none".

[Ian Stark]

I'm trying to downsize a load of m2t files from a Sony Z5 but these don't work in VirtualDub. Is my best bet to downsize using the camera's built in facility (and if so should I crop, squeeze or letterbox?!).

I am mixing these files on the timeline with widescreen SD PAL DV. Final output is to SD DVD and I was hoping to be able to zoom in on the HDV footage, which I guess I will not be able to do if I downconvert. Any other workflow recommended for m2t?

The footage is of people doing exercises on trampolines and it in tests it looks really dreadful on DVD. Curiously, I rendered the timeline using the MainConcept DVD Architect PAL Widescreen video stream preset, but DVDA wanted to recompress the video again. Did I do something wrong?

[Jeff Harper]

I have shot HD with the FX1000 and rendered out with Vegas to SD with excellent results. Downsizing via the camera does not produce great results. I believe, and some others do to, that the best results come from resizing in post. I believe that my camera and yours shoot extremely nice SD widescreen, and I shoot almost exclusively SD. The results are fantastic. I have been asked if some of my work was HD by potential clients. (It is doesn't look HD to me, but hey, I'm just making a point).

I usually use 720x480 Widescreen project settings in Vegas when converting HD, rather then using the native HD dimensions, but I've done it both ways, and see little difference.

As an aside, I see people shooting HD and downconverting a lot here. I know sometimes you must, but I just don't. Some cameras reputedly do not shoot great SD (the XH-A1 comes to mind), but my cameras do. The Canon HV30 does well also.

I think the key is the quality of the footage to begin with. Some folks (not you Ian) shoot HD expecting it to be a magic bullet and to produce "amazing" footage (just because it's HD). It does not. Poorly shot/lit HD footage looks as bad as poorly lit SD footage. Properly framed shots in sufficient light, the use of closeups obtained by moving the camera rather than by zooming and knowledge of basic shooting techniques are what create great video. And don't forget to lower the gain! Great quality footage will be very forgiving in post.

Some scenarios, particularly dance recitals, plays, speeches in poorly lit situations are often no-win when using a 1/3" chip camera. But weddings and for almost all other corporate work I find SD with these Sony cameras produces images that is excellent.

[Jeff Harper]

Oops, sorry Ian...I went on my rant and forgot to address your question.

I'm thinking you might bring your footage into Vegas using the project setting that match your HD footage...then you can zoom in as needed. Adjust the other footage with the pan and crop tool, or using the aspect ratio plug in...I think then you'd be good to go. Render out to desired output, and it will look fine.

[Ian Stark]

Hi Jeff - it was a good rant - I enjoyed it!

Since my post I have been doing a few unscientific experiments. I certainly agree that downsizing with the camera is not of an acceptable quality so that idea is canned. I'm actually happy about that as it means I can resize the 1440x1080 footage on the timeline (note that I only want to introduce a very slow crawl in to subtly emphasize certain things).

At the moment I am working with project settings matching the m2t footage. The PAL SD footage actually doesn't look too bad. I'm currently rendering out to AVI using the 1440*1080 Sony YUV preset. I will then see what's best for downsizing for the final SD DVD and I am guessing that might be VDub with Lanczos.

Thanks for the advice.

[Jeff Harper]

For DVD try rendering out to your normal SD DVD settings for MPEG 2. You might find the results surprising, unless you've tried it before.

[Jerry Amende]

Originally Posted by Jeff Harper

For DVD try rendering out to your normal SD DVD settings for MPEG 2. You might find the results surprising, unless you've tried it before.

This usually works pretty well for me. Per the tutorial I posted earlier, here are some suggested "tweaks":

1) Make sure your project properties has a "Deinterlace Method = Interpolate" (Blend works fine, too) as Vegas uses this to resize when rendering (even though we are not actually Deinterlacing). Also, Rendering Quality = Best.
2) Add a Sharpen FX set to 0.000 to each clip in the timeline. This is actually a bug in the Sharpen FX, but improves the quality of the final render.
3) Right-click each event in the timeline and set "Properties->Reduce Interlace Flicker" If the final render still contains moire patterns or excessive flicker, go to Plan "B" - intermediate renders &/or resizing or addng Gaussian Blur. However, normally Plan "B" is not needed.
4) Render to the highest bitrate you can fit on your DVD - you may need a bitrate calculator to determine the actual settings.

Good Luck!
...Jerry

[Frank Nagel]

I work with Edius 6 .
And i use also the VDub with Lanczos for downscale to SD AVI (lossless)
When i put the SD AVI in a SD-Projekt in the Timeline, I have to change the settings of the clip to 16:9
After VDub the Clip will be identified as a 4:3 Ratio. But that is just a click to do in Edius.

Before the converting to mpeg it is necessary to use the "sharpen" effect. In Edius i use it up to nr.10.
Without doing this, the DVD out of VDub looks very fuzzy.