I was wondering how and what methods people are using in their workflow in order to achieve the best possible DVD image possible. In the past I have been rendering HDV to PAL DV then to DVD but this resulted in the most ugly image quality... yuck!

I have been experimenting and so far the best method that seems to produce razor shape images is as described below:

(1)Take raw HDV file into Vegas/ any NLE and apply a sharpen filter don't forget to apply deinterlace and reduce interline flicker.

(2)Render HDV file to UNCOMPRESSED avi 720*576 (PAL DV size) but since my harddrive is limited I just use Motion jpeg instead (at the highest qulity setting and progresive setting). [This idea was suggested by another DVinfo user, I forget his name....rasie your hands if you read this! )

(3) Render this MJPEG file to mpeg2 DVD format using your favorate encoder.

Now the MJPEG clip looks superb, just excellent, however the final mpeg2 has some slight losses (in image quality), i'm still working on this, I think its to do with what quality settings you use in your encoder, but this is a time/quality tradeoff.

Anyway I would like to hear form other users experiance.


Anhar Hussain Miah

While not perfect, this does an excellent job at taking a Sony HDV frame and converting it to NTSC by pulling out the even and odd fields, resizing each down to 960x480, snagging the middle of the frame by cropping off the sides and either the top or bottom line (now having each field at 720x478), then resizing down to true 720x240 and weaving to get true interlaced NTSC:

x=AviSource("D:\whatever.avi").AssumeTFF().SeparateFields()
Interleave(x.SelectEven().BicubicResize(960,480).Crop(120,2,-120,0),x.SelectOdd().BicubicResize(960,480).Crop(120,0,-120,-2))
BicubicResize(720,240).ComplementParity().Weave()

The advantage over the process you describe is that you don't lose the interlacing. So it really acts just like you originally shot it in DV. Proper aspect ratio and everything.

In the script you'll of course want to change "whatever.avi" to be any AVI file or VirtualDub signpost file. I personally use CapDVHS to snag HDV, writing it to a program stream .MPG file. From there I open it directly with that great modified version of VirtualDub that can read MPEG2 program streams. From there I frame serve out to a .VDR file, and open that .VDR file with this AVS script above. Finally you can open the .AVS file with pretty much any other NLE or compressor. It will look just like NTSC DV footage, right down to the funky swapped fields inherent to DV.

Note that the script is not perfect because the vertical resolution is compromised a tad. Not tragic, but it is a little bunged. Horizontal resolution is absolutely perfect. Doing it 100% the right way in AVISynth ends up with a script so long that it requires unreal amounts of RAM in the system to process it. And unreal amounts of time as well. For this reason I'm in the process of writing a speedy filter for VirtualDub that will perfectly convert HDV into NTSC at 720x480. (Better than DV because with this filter the color resolution will be 4:2:2!) To maintain proper interlacing, the filter will throw out half of the resolution from each field, so more grain if it's not lit well, but all things considered the result will be the best possible NTSC you can get from Sony HDV.

I also intend to make options to do letterboxed and anamorphic NTSC. A PAL version will follow shortly on the heels of the NTSC version. It won't change framerates at all (and as a VirtualDub filter it can't...) so if you want that trick then you'll have to get a bit fancier, probably deinterlacing and changing framerate in an NLE or with ConvertFPS in AVISynth.

-Lorin

Thanks Lorin! keep us posted!


Anhar Hussain Miah

The new AspectHD (build 3.2a) does an excellent job of down-converting HDV sources within Premiere Pro using the Export->Movie option. It retains fields and switches their order as desired, accomodates Pixel Aspect Ratios and the works.

To save on hard drive space, I typically render from a Cineform 1080i file to:

1280x720p30 (w/ deinterlace, PA 1.0)
720x480i60 (lower field first, PA 1.2)
and if I feel like 30p instead
720x480p30 (PA 1.2)

all in the Cineform intermediate file to save on disk space, since the Cineform file is 4:2:2 and has remarkable image quality. From there I encode via Encore DVD to 4:2:0 MPEG-2 for DVD (and the 720p file to 4:2:0 WMV-HD).

It's possible to render to 4:4:4 uncompressed.avi files, but since the delivery codecs decimate the colour space to 4:2:0 (or 4:1:1 for interlaced WMV), there doesn't seem to be much point except for frame grabs (and even most JPEG compression is 4:2:2).

-Steve

Why not go from adobe and media encoder to Mpeg2?
I did it this way, put into reeldvd, and made my DVD. Looked super.


Dave