Render HD to SD questions

ddm wrote on 7/16/2009, 4:45 PM
I've got an HD project in Vegas 9 that I've successfully made a beautiful bluray from. I now need to generate a best possible SD DVD and I've run into some problems. From the same Vegas timeline as my HD project, the SD generated mpeg 2 file looks a little ragged and jumpy. I noticed that my HD project has upper field chosen and all my bluray (mpeg 2 hd) renders have been excellent with this setting. when I switch project settings to DV NTSC widescreen, I notice that it defaults to lower field. I've tested both of these settings and they don't seem to matter as far as I can see. I have been rendering as "best" for my project settings as I have been unchecking the switch "maintain aspect ratio" when switching to SD to accomodate the slight changes in the ratios between HD and SD, otherwise I get slight black bars on the right and left.

Is there a better way to convert a beautiful m2v HD file into a decent mpg SD file?

Thanks.

Comments

John_Cline wrote on 7/16/2009, 8:02 PM
Sure, you should be able to do this easily. There are a couple of settings that affect quality, not the least of which is the bitrate at which the video is encoded. First of all, how long is your program?
ddm wrote on 7/17/2009, 12:50 AM
The material is 1 hour 22 minutes. I've always let the bitrate be what it defaults to, which is 8 mb max , 6 mb avg, something like that. I used to have success with this project burning sd dvd's but once I converted it to hd, I stopped doing dvd tests and have been doing bluray tests. Getting a decent sd dvd has proved challenging.
John_Cline wrote on 7/17/2009, 1:21 AM
Since you will be resizing from HD to SD image size, make sure you select a "deinterlace method" in the "Project Settings", use "Interpolate." This is very important, even though you won't actually be deinterlacing, it absolutely needs to be set to something other than "None."

Select "Main Concept MPEG2" > "DVD Architect NTSC Widescreen" Go to Custom, set the Render Quality to "Best." Then set the quality slider to "31" and use a two-pass VBR with the following bitrates:

Maximum: 7,984,000
Average: 7,256,000
Minimum: 3,624,000
ddm wrote on 7/17/2009, 10:52 AM
Wow. I'm trying that now. How did you come up with those numbers? Thanks.
ECB wrote on 7/17/2009, 11:04 AM
I have been rendering as "best" for my project settings as I have been unchecking the switch "maintain aspect ratio" when switching to SD to accomodate the slight changes in the ratios between HD and SD, otherwise I get slight black bars on the right and left.

You can also eliminate the letterboxing by checking Stretch video to fill output frame size in the Render As panel or crop.

Ed
ddm wrote on 7/18/2009, 12:45 PM
Thanks, Ed. Tried it and it seems to work well.
ddm wrote on 7/18/2009, 12:48 PM
Thanks, John. Looking at the DVD now and it looks very good. I did a search and found a previous message that you mentioned the bitrate calculator. Nice.
Al Min wrote on 7/22/2009, 1:22 AM
John, you wrote:

"Since you will be resizing from HD to SD image size, make sure you select a "deinterlace method" in the "Project Settings", use "Interpolate."

I couldn't find the tab. Do you mean "Project Properties?" If so, where is the deinterlace setting?
ddm wrote on 7/22/2009, 9:31 AM
Allow me to answer for John as his tip worked wonders on the SD DVD. It is under Project Properties and in the "Deinterlace Method" dropdown, the default is "none" but you can also choose "Interpolate" or "Blend". Project settings and properties are one in the same, I think. You get to settings by choosing "file/new" or in an existing project your can get here by going to "file/properties".
sguandal wrote on 7/22/2009, 1:43 PM
Excellent pieces of advice here! However (and forgive me for being so naive), once you have your MPEG2 piece done and ready to be imported into DVD Arhitect 5.0, how do you add the audio that you had in your original vegas Pro project?
ddm wrote on 7/22/2009, 8:28 PM
If you rendered the first piece as AC3 audio, and the files start at the same time, then you can use the same ac3 file. I used the same ac3 file for both my HD m2v video file and my mpeg2 SD video render. Very important that the start marks be the same in both versions and DVD Architect will automatically link the audio if it is named the same as the video file. As in...

wa20v65.m2v
wa20v65.mpg
wa20v65.ac3

They need to be in the same directory as well to be seen automatically.
Al Min wrote on 7/22/2009, 11:05 PM
Thanks DDM for standing in for John. Got it all sorted. Followed the instructions exactly, and golly me, am I impressed with the final result! Looks really good on my 37" plasma. And the burning in DVDA seemed to be a lot quicker too - 25 min home movie following this formula burned to disc in under 4 minutes. Thats really quick for me. Does this formula ensure quick DVD burning? In the past, for me it has taken longer to burn the DVD than to render the file in Vegas. Very interesting. Thanks so much for this work pattern.