View Full Version : Best HD to SD conversion?


Ben Freedman
June 25th, 2006, 09:28 AM
Howdy...

If I have some HDV and I want to deliver on SD, is it better to:

1) Capture HDV, place in SD project to edit, then export

or

2) Capture HDV, edit in HDV project, export to SD settings?

Thoughts?

Best,

Benjamin


----------------------------------------------------------
http://www.neo-fight.tv [The "Techno-Debate" Video Podcast]

Chris Barcellos
June 25th, 2006, 02:47 PM
One other possiblity exists. You can shoot HDV, down convert out of the camera to DV capture, then edit in a DV timeline.

The consensus I have seen on the boards in this forum is that your best result would be from a full edit in HDV, render to HDV, then down convert from there to your whatever format. Of course the underlying question there is what do you mean by edit in "HDV". The consensus again is best results are obtained using an intermediate format .avi file to edit with, ie., Cineform. Other possibility is native edit with HDV .m2t files.

Kyle Karges
June 26th, 2006, 12:49 PM
My name is Kyle Karges.
I run a wedding video business and use the Sony FX1's(6 of them actually).
When I digitize the footage into FCP 5.1.1 it always says it is coming in medium quality.
Does anyone know how to fix this or have a better method to get the best quality footage into the computer?

Thanks ahead of time,

Kyle
K and K Productions, Inc
www.kandkpro.net

Robert Young
June 29th, 2006, 08:19 PM
Benjamin
I have done this both ways, and for me there is not a black and white answer that is always correct. There are costs ( more complex workflow, more time spent) and benefits (how much better quality images) that need to be balanced for each project.
I'm assuming that we are talking about Sony HDV.
The simplest workflow is to record in HDV and capture in DV using in-camera downconvert, edit as DV, and transcode to DVD- if that is your final destination. The final images, IMO,are significantly better than you get from small camera DV recording.
Or,you can capture as HDV, transcode to Cineform CFHD .avi, edit as HD, and then either downconvert the CFHD to SD size and transcode to DVD, or use something like Procoder2 to transcode the CFHD directly to m2v for DVD. This results in final images that are slightly more attractive. I personally think the improvement is due to slightly better color rendition because color sampling is consistant throughout the transcoding: HDV- 4:2:0> CFHD- 4:2:2> DVD- 4:2:0; instead of HDV-4:2:0> DV- 4:1:1> DVD- 4:2:0.
When viewing the final DVD footage on a 42" Sony TV, to my eye there is not a dramatic difference in the results of these workflows.
So, I am finding that most of the time, if the project is destined for DVD and TV viewing, I take the easy route and just capture DV from camera downconvert. If it's a project I want to archive for possible HD delivery at a future date, or think I might want to make available as WMV HD, I will edit as HD.
There are others, who have sharper eyes than mine, who will take issue with my conclusions- but this is what I am actually doing at the present time.

Ben Freedman
June 29th, 2006, 08:52 PM
Howdy...

Assuming you wanted to go from HDV to DVD, why would you render to DV first?

What I mean is, why go HDV-4:2:0> DV- 4:1:1> DVD- 4:2:0, when you could just go HDV 420> DVD 420.

Seems strange to me to put the 'dv' step in the middle...

Best,

Benjamin


----------------------------------------------------------
http://www.neo-fight.tv [The "Techno-Debate" Video Podcast]

Douglas Spotted Eagle
June 29th, 2006, 11:34 PM
Ben has it exactly right. If you're going to DVD, there is no gain and a fair amount of loss going to DV prior to going *back* to MPEG 2 for DVD delivery. Keep it all in the same color sampling for best image quality.

Yasser Kassana
June 30th, 2006, 05:00 AM
Assuming you use Vegas & achieving 4:4:4 (i.e. full colour resolution) as far as my understanding when you downscale HDV 1440*1080i 4:2:0 to SD 720*576 the way the pixels get re-arranged it ends up as having 4:4:4 colour resolution, now my understanding in the theory is quite limited, however I have done this in practice and from my experiments it does indeed look good.

Here is what I do , which hopefully you should be able to replicate.

Assuming your using Vegas (its what I use)

Place HDV in the timeline and edit as normal

apply sharping filter (I use about 0.450) you should experiment and see what you like.

also in the properties tab set to progressive and interpolate as the de-interlace method.

then render the clip (i suggest you use about a minutes worth of clip, because when I'm testing, I always do very small clips that way I can do many different combinations to see what variable has what effect, then when I am happy with the combinations I can do the full clip.)

when rendering set to quiktime and go to custom, find the compression and set it MJPEG (OK, in theory you are suppose to set it to uncompressed, but to my eyes there is really no difference, and plus it saves on HDD space)

now, take a look at the quiktime file, it should look amazing, in fact it should (on a small monitor, mine is 17"" CRT display) you cant tell the differance between the HD file and SD file (the differance is small)

NOW encode this file to MPEG 2 DVD and use the highest settings in the encoder such as set DCT precision to 10bit.

The mpeg2 file should look miles better than if you whent HDV>>DVD

Robert Young
June 30th, 2006, 12:04 PM
Benjamin
I am agreeing with DSE. The final DVD image quality is better by avoiding a DV conversion in the workflow, again, probably due to the color sampling issues. My point was that, to my eye, watching the final output on TV, there is not a dramatic difference in image quality.
Therefore, I am often not reluctant to use the quick and dirty workflow of in-camera downconversion and editing as DV.
On the other hand, with newer, state of the art hardware, it would be as quick and efficient to keep the project in HD throughout the workflow. That's probably how I'll do it whenever I do my next system upgrade.

David Mills
June 30th, 2006, 01:24 PM
So I have made my project in a hdv(hdv 108050i) sequence and find that I need to deliver SD. But not for DVD , I need to provide a digibeta master. My post house asked for the project on mini dv tape...What does anyone suggest to ensure the best possible quality. Is this the best quality I can give them? Seems a massive shame to do this

I tried to make a DV PAL quickti.me out of the HDV timeline When I exported out of a HDV timeline to DV pal in quicktime settings it looked REALLY soft. I saw someone mention exporting the project in HDV first. Is this the better way to go?

Many thanks.