HD>SD downconversion Mac/FCP only

[Alister Chapman]

When using compressor you should activate the advanced Frame Controls and select the "better" or "best" resize filter. Turning Anti-alias up to around 40 or 50 reduces any jaggies.

Doing this makes a huge difference to the quality of any frame resizing such as from an EX to SD. You can set this up on any preset so you can go straight from the timeline to m2v for DVD or DV or H264 in one hit. Renders do take longer but you only have to do the one step.

[Brooks Graham]

It's been mentioned several times that Compressor's Anti-alias feature under Frame Controls should be used when scaling down. But it's always been my understanding that this feature is only used when scaling *up*, so I've not tried it for that purpose.

Curious. Has anyone ever a/b tested downscaling behavior while using it?

[Dominik Seibold]

Originally Posted by Alister Chapman

When using compressor you should activate the advanced Frame Controls and select the "better" or "best" resize filter. Turning Anti-alias up to around 40 or 50 reduces any jaggies.

I just tested some combinations of quality-settings and anti-aliasing-settings with 10 seconds 1080p converting to 720x480p. I attached the results to this post in this order:
quality=better, anti-alasing=0 => rendering-time: 0:27
quality=better, anti-aliasing=100 => rendering-time: 4:27
quality=best, anti-aliasing=0 => rendering-time: 0:33
quality=best, anti-aliasing=100 => rendering-time: 7:37

I actually can't see any difference in quality, but a lot of difference in rendering-time.
Btw, compressors manual says that the anti-aliasing-feature is only to be used for upscaling.

[Dominik Seibold]

Now I tested converting the result of quality=best, anti-aliasing=0 back to 1080p with some different settings:
quality=better, anti-alasing=0 => rendering-time: 0:41
quality=better, anti-aliasing=100 => rendering-time: 1:33
quality=best, anti-aliasing=0 => rendering-time: 1:20
quality=best, anti-aliasing=100 => rendering-time: 2:19

The last attachment is the unprocessed 1080p-source.
I had to decrease the jpeg-compression-quality to be able to upload the pictures to this forum, so there are a lot of jpeg-artifacts, especially in the dark sky.

[Simon Denny]

I read a post in here somewhere that said: Edit in the Sequence settings that are as close as you can come to matching your final output. In other words, if you aren't going to author a Blu-ray disk or some other HD final product -- then don't edit in HD!! Edit in SD. Choose sequence settings that match your final output -- not the source footage.

Ok this makes sense I think but what are the settings for doing this.
My last shoot was 1920x 1080i pal
So what should my my easy setup be, and also sequence settings be?


Simon

[Sverker Hahn]

Originally Posted by Simon Ash

-- then don't edit in HD!! Edit in SD. Choose sequence settings that match your final output -- not the source footage.

I edit in HD, rendering is not necessary and add my HD sequences to the SD timeline. Then I have to render and after that I create the .m2v files.

[Jon Goulden]

Unless I'm confused (quite possible), the timeline determines the output but you can drop whatever you like into it (in current FCP) and it will edit at the resolution of the inserted clip. You can zoom/pan within an HDV clip (up to about 4x) in an SD timeline and still get full SD quality output since the HDV resolution allows for this.

[Christopher Drews]

Originally Posted by Evan Meades

Hi Christopher, sounds good! But why not the MXO2 version?

I tried something similar by using the EX3's SDI SD output to play out (720P50) and record a 1 1/2 hour program straight to my DVD recorder> I used my Blackmagic Declink SD card so I could monitor the SDI signal/sound. Worked well, although I had to use the DV D recorder's S input (best it has) plus do bit of post tweaking to the VOB file via MpegStreamclip (losslessly I believe & quick!) to get a m2v/ac3.

Saves a lot of time, especially for a long recording. Not sure about using this method for shorter projects as although the SDI output with SD downconvert was the best signal out I believe, I'm not sure it beats other software methods.

Do you think the MXO would be better?

Evan

MXO2 has the same feature. I just wanted to differentiate between the two products as their seems to be large price gap and utilization difference.

Let me just be clear that your workflow with the EX3 is different than the workflow I was mentioning, as I believe from your post that the EX3 was doing the downconversion to make the DVD dub. This wasn't what I was getting at. The MXO can do this directly from the FCP timeline in its native HD form. So you would transfer your digital EX3 files into FCP and then play out via the MXO.

As for your second question about Method - this works just as well for shorter projects in my opinion. Again, if you do a bunch of these types of "on the fly" conversions, I'd totally recommend getting a second system just to capture.

Editor 1 w/ MX0 (Player) >
Editor 2 w/ SD Capture Card (Recorder) >
SD Monitor out of Editor 2 (NTSC / PAL)

There is another side to this workflow - frame rate - lets say I shoot everything 23.98 and need to make it NTSC. The MXO also will add the necessary pulldown. I haven't tried PAL yet so I'm not sure if it will convert that.

As for quality - SDI is SDI , Analog is Analog - We could debate whether the picture would look better if you stayed digital but it would be negligible even to the best (if your codec stays the same). Ultimately though, I would stay away from S-VIDEO. Component output from the MXO will give you an improved image over that Y/C junk. I liken S-VIDEO with Composite.

Hope this helps,
-C

[Dominik Seibold]

If software-methods can be free, perfect-quality, easy to handle, flexible and fast at the same time, then why use hardware-methods?

[Andy Nickless]

Originally Posted by Dominik Seibold

I actually can't see any difference in quality, but a lot of difference in rendering-time.
Btw, compressors manual says that the anti-aliasing-feature is only to be used for upscaling.

Interesting comparisons, Dominik.
Thank you for taking the trouble to post those.

[Andy Nickless]

Originally Posted by Dominik Seibold

If software-methods can be free, perfect-quality, easy to handle, flexible and fast at the same time, then why use hardware-methods?

Ever since I've been doing video, it's been generally accepted that Hardware conversion is better than Software conversion.

With this in mind, I would certainly like to try Hardware conversion, but for some obscure reason nobody seems able (or willing) to suggest a suitable Deck for converting to.

I've had plenty of suggestions for Blackmagic, Kona and Matrox to convert HD but what should I stick on the end of it to catch the SD?

It would seem the deck needs Component or SDI (In) and I assume these Decks are pretty expensive.

I only want to use the SD for DVD.
Any suggestions, anyone?

[Perrone Ford]

Andy, why stick anything on it? If you are playing into an Aja, or Blackmagic card, just let it save the files to your hard drive, and make your DVD from there. Why go OUT to a deck, which you'd then have to digitize back in the computer?

Maybe no one's suggesting anything because it's totally unnecessary.

[Dominik Seibold]

Originally Posted by Andy Nickless

Ever since I've been doing video, it's been generally accepted that Hardware conversion is better than Software conversion.

That thinking is really silly.
hardware can't be better than software in terms of picture-quality, because the thing which does its image-processing-job in the hardware is also just a piece of software, but software with realtime-capability-restraints.
Software on a PC can use as much time as it wants to do its job, so the programmer can concentrate much more on picture-quality.

[Matt Davis]

Originally Posted by Dominik Seibold

That thinking is really silly.

Exactly. Hardware is for people with time constraints and deep pockets. I invested £20k in Digital Rapids encoders a while back (for encoding 300+ hour long DVD-Rs to three streams of Real Media each), and they paid for themselves in 4 weeks. I tested the whole job out using a software codec (IIRC something like 'Moonshine' or whatever - some talented Russian developers anyway) and the software version was better than the Digital Rapids, but took forever.

Business case for both methods.

I have heard from colleagues working for Auntie Beeb that Compressor, when given annual leave, can do amazing things that a quarter of a million quid's worth of Alchemist sweats over.

We've just got to balance deadlines, budget and quality.

I'd look very carefully at Matrox hardware and progressive material - there's some interlacing mojo going on that we didn't pin down.

[Mitchell Lewis]

Everyone's talking about converting their footage to SD. What about converting a finished project with graphics, titles, etc....? Is no one interested in that? (other than me)

I would like to shoot and edit in HD. That way, when my client comes to approve the project, they will be seeing it in glorious HD on our 24-inch JVC HD monitor. I could then give them a Blu-Ray version of the project (if they have access to a blu-ray player....doubtful)

But then, I'd like a good solution to converting the entire project to SD so I could:

1) Make a DVD version of the project
2) Make a MOV version of the project to send to the local broadcasters
3) Make an WMV or Flash version of the project. (might be able to do this in HD...dunno)

I'm hoping that Compressor is going to be the solution.