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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Best way to go from HD>SD?

orre

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Hi everyone
I'm trying to get a nice Uncompressed 10-bit PAL render 720x576 16:9 From a 1920x1080 prores 444.
The material has been sent to FCP from COLOR. Everything looks sharp and nice in HD but the SD-files looks quite bad.
Someone mentioned shake might do the downrez a bit better but I don't have it.
Do you have any nice tricks up your sleeves?
 
Compressor. It depends on your footage. If you have fine details, thin lines etc. it can get a little messy. Sometimes I get great results with scaling the footage down in After Effects. Hope that helps.
 
Set up a 10 bit uncompressed timeline in FCP and then cut and paste your timeline into this. Results are not in the league of using a hardware solutions such as Snell & Wilcox Alchemist, however we have used this route for many broadcast productions. This route allows you to individually adjust individual clips that may exhibit aliasing problems whereas the Compressor route makes individual adjustments impossible or certainly more difficult.

If your footage looks bad then I would be looking at the source footage for a cause - we use this option for RED & HDCAM footage and don't generally get problems. As stated above the best route is hardware and the Alchemist is the way to go :o)

Scott
 
After Effects is by far the best common desktop solution. FCP and Compressor have some pretty bad scaling algorithms IMHO.
 
That really depends on how you set your frame controls. I've gotten very good conversions out of compressor, going down and coming up.
 
Thanks for all the input!
Scott, do you mean I should make the new timeline 720x576?
What I have done now is just klicking export from the prores timeline and made a custom Uncompressed setting.
I actually haven't tried compressor since I thought it used the same algorithms as fcp. It's worth a trie though.
I don't have much experience with AE, would you like to enlighten me a bit more?
Just exported it from a 1920x1080 timeline.
What exactly is aliasingproblems and what can I do in this case to beat it? (if I have them)
-Alex, What's framecontrols?
Sorry, a lot of questions...
 
In AE it's pretty straightforward: import your footage, make a new composition, you can use PALD1/DV preset and just drop your footage on the timeline. With the footage layer selected in the timeline press "s" once for scale values to appear and enter a new value (around 41% will scale HD to proper width in SD frame) most of the time I end up using 41.5% because that removes some of the antialiasing that can be seen right on the edges of scaled-down HD footage when using 41% scale. It will crop a few pixels left&right but I mind that less than visible antialiased edges.

If you start getting aliasing problems there's nothing much you can do except invest in higher-end hardware solution for downresing. Usually that happens when you have some graphic elements in the frame, which were built for HD so when they're scaled down their usually sharp edges can start looking jagged in SD size. If that's the case, best thing is to create SD-sized graphic elements.

In Compressor when you create or select a certain preset for converting your footage, open Inspector (Window->Show Inspector) click on the third tab - that's the Frame Controls tab. Firs you enable the frame controls by switching to ON and than set the Resizing Controls to Best. There are two sliders (Anti-alias and Details Level) that affect the quality of resizing as well. "Anti-alias" will help you avoid jagged edges by softening them especially when you upscale your footage and "Details Level" will help you retain sharp edges and fine detail. You have to set them according to your footage.
 
Thank you Marin!
I will try these tricks today. Sounds promising.
 
Just a little update. After much rendering in different software and a call to one of stockholms biggest posthouses (who also suggested shake to my surprice) I realized that I can make uncompressed 10 bit pal thru my MXO2 mini. It looks awesome!
Only problem now is graphics made in AE in 720x576 Animation, imported to fcp. It looks ok but not perfect as the footage.
 
orre, I'm not sure what you mean by "It looks ok but not perfect as the footage" In what way are graphics worse than the footage?
 
It's jagged in the edges.
At first we did the graphics in 1920x1080 and put it over the footage in fcp and then rendered SD thru the mxo2 but that did not look acceptable so we did the graphic SD straight out from AE, then put it over the SDfootage in fcp and rendered again. Much better but not perfect. The problem seem to occur when the mov-file gets sqeezed to the 1024x576 aspect ratio. When it is viewed in 4:3 there is no "jaggines" in the graphics.
Another strange thing that I recently saw is that the SD-renders is acctually not the right size.
If i klick on the film, finder will say its 720x576 but when I open it in quicktime It's something like 1027x575 instead of 1024x576. It's to wide.
I have shanged the presentationsettings in quicktime but no one is right.
Since the original footage was 2048x1024 I had to make it 2048x1152 with letterbox before the downrez but I don't think thats the problem.
Any ideas?
 
I don't have MXO2 so I cannot try out what you did, but it seems like you should have created graphics in 1024x576, square pixel, that way you'll have the full resolution of SD widescreen and FCP won't have to do anything with it. Also, it looks like MXO2 created anamorphic SD out of your 2048x1152 footage. If you can, make the footage 1024x576 square pixel and import it in FCP, drop it in a new sequence and FCP will automaticly set the sequence for you with the right settings. Create graphics in AE with comp settings 1024x576, square pixel, render it out and place in FCP. Everything should be ok.
If you can't make your footage square pixel and you're stuck with anamorphic, set the sequence in FCP as anamorphic (720x576, aspect ratio: DV PAL 5:4, pixel aspect ratio: PAL CCIR 601, and check "anamorphic 16:9"). Now you can drop your footage in the sequence and import graphics. In the browser, right click your graphics file from AE and go to Item Properites>Format... than make sure "Anamorphic" is unchecked and change "Pixel Aspect" to Square by right-clicking on the default value (mine is "PAL -CCIR 601). Now you should have everything matched.
 
I don't have MXO2 so I cannot try out what you did, but it seems like you should have created graphics in 1024x576, square pixel, that way you'll have the full resolution of SD widescreen and FCP won't have to do anything with it. Also, it looks like MXO2 created anamorphic SD out of your 2048x1152 footage. If you can, make the footage 1024x576 square pixel and import it in FCP, drop it in a new sequence and FCP will automaticly set the sequence for you with the right settings. Create graphics in AE with comp settings 1024x576, square pixel, render it out and place in FCP. Everything should be ok.

I am afraid this is not correct at all.

1024x576 is not a real video format, it is a workaround to allow working in square pixels on systems which do not understand pixel aspect ratios. All PAL deliverables, whether that is tape, DVD or whatever will be 720x576, so if you work 1024x576 you will be converting to 720x576 for your deliverable. If you use FCP to do this conversion you may well see scaling artefacts, since FCP's scaling is not high quality.
 
Yes, I have to deliver in 720x576 Anamorphic. So this can't be done with fcp, compressor or AE with a satisfying result according to you Nick?
What should I use then? And don't say hardware please.
I might try Shake as a final desperate attempt.
 
So this can't be done with fcp, compressor or AE with a satisfying result according to you Nick?

I only said be wary of FCP. Of the applications you list, I have seen the best results out of Shake, but it is very slow. But AE and Compressor can give good results too. Ironically, sometimes the results can be too sharp, which confuses the de-interlacers on some LCD monitors (video not computer) and causes jaggies. Softening slightly can often help.
 
We softed the graphics one step in AE.
So would you make it all in a HD-timeline i fcp, then send to compressor or make it in a SD-timeline?
I mean does it matter if the footage and the graphics are SD or HD when sent to for example Compressor since I can get them both look good in SD when they are not put together.
A bit confusing maybe?
 
1024x576 is not a real video format, it is a workaround to allow working in square pixels on systems which do not understand pixel aspect ratios. All PAL deliverables, whether that is tape, DVD or whatever will be 720x576, so if you work 1024x576 you will be converting to 720x576 for your deliverable. If you use FCP to do this conversion you may well see scaling artefacts, since FCP's scaling is not high quality.
Nick, you are correct about 1024x576 not being a real video format, but I suggested that because that way you have more pixels to work with and usually I leave converting to anamorphic for the last step or I send tga sequence to guys who transfer it to beta for delivery and they do anamorphic with high-quality hardware. I did a lot of stuff in 1024x576, rendered it out from FCP and converted it with Compressor or AE with great results.

Oskar, I do everything in HD, then Export Movie (don't check "Recompress all frames") and finally scale it down with Compressor or AE. Never had any problems with graphics that way.
 
I only said be wary of FCP. Of the applications you list, I have seen the best results out of Shake, but it is very slow. But AE and Compressor can give good results too. Ironically, sometimes the results can be too sharp, which confuses the de-interlacers on some LCD monitors (video not computer) and causes jaggies. Softening slightly can often help.

Compressor uses the same algorithms as Shake, both should do a very good job. They have the ability to do VERY good spacial and temporal conversions on a par or better than hardware devices.

The trick is to make use of the frame controls. Like anything it has to be set up correctly.
 
Compressor uses the same algorithms as Shake, both should do a very good job. They have the ability to do VERY good spacial and temporal conversions on a par or better than hardware devices.

The trick is to make use of the frame controls. Like anything it has to be set up correctly.

I see. Good news then I guess. The milliondollarquestion is of cource, what settings is best for graphics with hard sharp edges if I want to do PAL uncompressed 10 bit?
I understand that there is no golden value but whats the most common settings to try first?
I don't think I can use frame controls with uncompressed?
What's "spacial and temporal"?
 
I just did a small test. I made 2048x1152 graphic and put it in AE composition of the same size. Then I made 2 comps, one with PAL anamorphic and one with square pixel (1024x576) settings. I put my 2k graphic layer in both of them and animated scaling from 100% to 50%, just like HD->SD. I exported both comps in uncompressed 10bit and imported those files in FCP. I created 2 sequences in FCP, one PAL anamorphic where I dropped anamorphic render from AE and one square pixel where I put square pixel render from AE. Then I exported both sequences from FCP with PAL ANAMORPHIC settings as for the delivery. Square pixel footage holds much better when it was converted into anamorphic than anamorphic did. Take a look:

anamorphicvssquare.jpg
 
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