View Full Version : Best way for Aspect HD to DVD output?
Alex Raskin August 21st, 2006, 03:00 PM OK, so AHD high def footage is edited in Premiere Pro.
For standard definition version, DVD is still king.
PPro (at best settings - I use quality 5, 8Mbs CBR) does a passable AHD -> DVD encoding job.
But comparing to the best commercial DVDs, I see much difference - and not in my favor.
On my DVDs, I see what seems to be macro raster (for the lack of better definition) that limits the image's resolution. Sometimes I see the same in commercial DVDs; but the best of them don't have such artifact. The immediate problem is that my DVD image looks "muddier" or more "defocused" that it should be.
Note: I do not have any problems with motion artifacts. Just the general look that seems lesser resolution than commercial DVDs.
Seems like PPro's way (scaling? DVD encoding?) could be improved.
Now, I don't insist on using PPro for the DVD encoding. I tried TMPGenc, but I have an ancient version that does not understand AHD files as input.
What workflow/software should be used for the absolutely best, commercial quality AHD HD -> DVD encoding?
David Newman August 21st, 2006, 04:18 PM We are upgrading to the highest grade scaling we partically implement. Much of the old scaling algorithms used bilinear or equilivent, new stuff is much nicer. It will be a free upgrade in the next releases of Prospect HD and Aspect HD. It is already working under Prospect HD, so that will come out first.
For now : if the highest quality scaling don't use Premeire Pro to the encoding or scaling. Export to HD as a CineForm Files. Then scale that to SD (use CineForm again) -- VirtualDub has some nice scaling options (for progressive material only) to produce a SD master. Then encode that with your DVD authoring app.
Alex Raskin August 21st, 2006, 05:00 PM Just tried exporting from PPro to AHD avi (no rescaling); then importing that avi to AE 6.
From AE 6, export to DVD m2v file.
Guess what :) AE 6's scaler is so much better than PPro's! Major improvement in image quality.
A-B comparison per frame shows that PPro's output is simply more blurry than AE's. Probably a different scaling algorythm.
Also, color fidelity is better in AE too.
Now, on to trying the new version of TMPGenc Xpress. It should be able to handle HDV files as input. Let's see if it beats AE in quality. Settings seem to be more elaborate in TMPGenc. I'll post the results here soon.
Alex Raskin August 21st, 2006, 06:33 PM TMPGenc Xpress 4 results: better than PPro but worse than AE 6.
Disclaimer: T Xpress used m2t file as input. That m2t is way more compressed than AHD avi I used as AE's input. Thsi may explain some sharpness loss right there. T Xpress also accepts AHD avi as input, but I couldn't figure how to set it to understand its aspect ratio. It seemed to always output it as 4x3 pillowboxed. No such problem with m2t as input.
So far, AE seems to be a clear winner.
Since I can also manipulate the image in AE before encoding - like deint, levels etc. - I think AE is the way to go.
So here's the step-by-step:
1. Edit your Aspect HD PPro project as usual.
2. Render finished project as Movie, avi, Cineform HD.
3. Import that AVI into AE 6. Render into MPEG2-DVD, Quality 5, Bitrate 8.0 CBR (high quality settings.) This will result in a great quality m2v file.
4. Go back to your PPro project and render audio only in ac3 format.
5. Make sure both m2v and ac3 files are in the same folder. Assign the same names to both AE 6 output video m2v file, and your PPRo audio ac3 file. (keep the file extensions respectfully, of course.) Discard PPro's m2v and AE 6's wav files.
6. That's it - import your AE' rendered m2v video into your fav DVD authoring software, it'll automatically find its paired ac3.
Burn away - the quality is much higher now than with the PPro -> DVD direct.
Richard Leadbetter August 22nd, 2006, 12:16 AM Personally I use AviSynth to get this job done. AviSynth is a scripting language that allows you to interprete practically any video file and manipulate it in just about any way. You can learn all about it here (http://www.avisynth.org/) and even a passing AviSynth knowledge can perform a number of very useful tasks in post.
In all these examples, it assumes that your CineForm AVI is on the root of c:\ and called 'footage.avi'.
It should possess a quality advantage in that I do not believe your current methods are using Lanczos scaling.
Here's the script I use to convert a progressive source into 480i, letterboxed. Things could get more complex if pull-down etc are factored in. The dimensions of the letterbox might be a bit off - in truth I never really use this script:
# Convert to letterboxed NTSC, 720x480i, 29.97fps
AVISource("c:\footage.avi")
LanczosResize(720,366)
AddBorders(0,57,0,57)
ConvertFPS(59.94)
SeparateFields()
SelectEvery(4,0,3)
Weave()
And for 16:9 anamorphic
# Convert to anamorphic NTSC, 720x480i, 29.97fps
AVISource("c:\footage.avi")
LanczosResize(720,480)
ConvertFPS(59.94)
SeparateFields()
SelectEvery(4,0,3)
Weave()
This is the one I use for a 4:3 pan and scan effect, from a 1280x720 source (the other scripts will work on any progressive source). It essentially discards the edges of your source. Clients tend to want this one more often than I would like :(
# Convert to 'Pan and Scan' NTSC, 720x480i, 29.97fps
AVISource("c:\footage.avi")
Crop(160,0,-160,0)
LanczosResize(720,480)
ConvertFPS(59.94)
SeparateFields()
SelectEvery(4,0,3)
Weave()
Drag and drop your script onto VirtualDub to see the results. Most (if not all) MPEG2 encoders will accept AviSynth scripts as source files too - and if they don't just use VirtualDub to run out as another AVI (I tend to use the lossless Huffyuv codec outside of the Premiere editing environment to ensure no loss of quality, but CineForm is just fine). The resultant 480i AVIs should be encoded into MPEG2 with upper field first.
If your source is 1080i based, these scripts could easily be adapted - in one of two ways:
1. Simply discard one of the fields, leaving you with a 1920 (or 1440) x 540 image, which is then resized.
2. Run the source through a smart deinterlacer to make it 1920/1440x1080 progressive, then run that through the resizing part of the script.
In theory the second method will produce marginally better results. In practise I wonder if any one would notice the difference.
These scripts can also be adapted with a simple bit of common sense to produce PAL compliant 720x576, 25fps streams - but if your source file is 29.97/30/59.94/60fps, you may notice judder on panning shots.
Alex Raskin August 22nd, 2006, 05:12 AM Note that Bicubic resize algorythm is more precise than Lanczos. You may want to change that in your script.
To me, since both AE and your scripts do require a rendered avi as input, AE wins easily. For people without AE 6, I guess VDub is a very good choice.
However I personally had mixed results with VDub - sometimes it gives strange errors on render and refuses to finish outputting *some* files.
Richard Leadbetter August 22nd, 2006, 01:53 PM Interesting - everything I've read says that Lanczos produces a superior output to Bicubic. However, I do wonder if there is that much difference when downscaling as opposed to upscaling.
Certainly, the AviSynth documentation (http://www.avisynth.org/Resize) definitely prefers Lanczos, and it certainly tallies with my experience so I think the script will remain as is for now.
Did you try the scripts? Could you elaborate on how AE wins easily?
Here is some more reading (http://www.avsforum.com/avs-vb/showthread.php?t=460922&page=1&pp=30) on the Bicubic vs Lanczos debate. A bit too highbrow for me - I prefer to use my eyes :D
Alex Raskin August 22nd, 2006, 02:26 PM I go by what TMPGenc documentation says. It says that Bicubic is (one of) the highest quality scaling out of their options, read here (I just copied their PDF page):
click here (http://primehd.com/images/resizecomp.gif)
TMPGenc folks (who I trust implicitly since they make their MPEG encoders since before I was born... virtually speaking ;) ... go on to say that Lanczos algo, while OK, does produce extra artifacts - read above.
Challenged by your question, I double-checked this issue further, and yes AVS forum was way theoretical.
But this page seems to set the record straight:
http://www.cambridgeincolour.com/tutorials/digital-photo-enlargement.htm
Look how Lanczos produces aliasing artifacts around the steps, while Bicubic does not.
> Could you elaborate on how AE wins easily?
AE vs VDub: when filters and processing engine quality are taken into consideration, I'm sure you can see the answer.
I did apply both Re:Vision FieldKit Deinterlace and AE's Levels to my footage with fantastic results in AE 6.
See 6 steps in my earlier post above... the sharpest looking DVD video, baby :)
David Newman August 22nd, 2006, 02:51 PM Alex and Richard,
Neither BiCubic or Lanczos is better than the other for all conditions. I think the AVISynth docs point out why TMPGEnc favors BiCubic as it is not as sharpening giving the MPEG encoder a harder time.
from http://www.avisynth.org/Resize
".. Lanczos is NOT suited for low bitrate video, the various Bicubic flavours are much better for this. If however you have enough bitrate then using Lanczos will give you a better picture..."
Generally if you are going to encode your DVD with as many bits as possible, Lanczos will be fine. We use Lanczos for the resizing within HDLink, as the CineForm codec can handle the nice sharpening without issue.
Marty Baggen August 24th, 2006, 09:34 AM TMPGenc Xpress 4 results: better than PPro but worse than AE 6.
So far, AE seems to be a clear winner.
Since I can also manipulate the image in AE before encoding - like deint, levels etc. - I think AE is the way to go.
So here's the step-by-step:
1. Edit your Aspect HD PPro project as usual.
2. Render finished project as Movie, avi, Cineform HD.
3. Import that AVI into AE 6. Render into MPEG2-DVD, Quality 5, Bitrate 8.0 CBR (high quality settings.) This will result in a great quality m2v file.
Alex,
this looks like a great approach. What are the Comp settings in AE that you import the Cineform AVI into? I set mine up for HDV, then when I select the MPEG-2DVD output from AE, I get an error.
Do you setup a SD Comp, then resize your AVI?
Marty
OnQ Film
Alex Raskin August 24th, 2006, 09:38 AM Marty, AE actually sets up the comp automatically to Cineform AHD video dimensions.
Just import AHD avi into AE, then drop it onto Comp icon. The comp will be created just right.
I assume you do have AHD installed on your PC. It is my understanding that once installed, AHD codec tells AE how to process it correctly.
Works for me without a hitch.
Your error may not be related to AHD per se, please read the error message and see how you can correct your workflow to avoid it.
Marty Baggen August 24th, 2006, 09:58 AM Thanks Alex... I'm going to try that right now.
I should have been more specific with my setup: I imported my PremierePro 2.0 timeline directly into AE7 and attempted my render from there. I presumed since the Premiere project is comprised of Cineform AVI's, it would save me the export step from Premiere?
I will output a single Cineform AVI from my Premiere project and do the steps as you describe..... but I still wonder why AE won't render the imported Premiere project to an MPEG2-DVD without the error message
"After Effects:AEGP Plugin Media IO Plugin: UNRECOGNIZED EXCEPTION"
I also get the same message when I try the same output with an individual Cineform AVI, captured and converted with Premiere Pro 2.
UPDATE: A classic example of system reboot curing all problems. I dropped a Cineform AVI into AE as you described, just as I was attempting earlier.... but after restarting my system, it works smoothly. Go figure!
Marty
OnQ Film
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