Can Premiere CS5 now resize HD to SD better than before?

[Steve Sykes]

Since moving to a 64bit bit platform my workflow has now had to change.

I was never happy with the SD quality produced using the Adobe Media Encoder (CS3) when exporting my XDCAM EX footage to SD and found better results using the workflow below:

Create sequence to match HD footage, frameserve using debugmode frameserver to virtualdub, resize using the Lanczos resize algorithm then frameserve to the TMPGenc to create my DVD.

The difference was very noticeable and produced a sharper image. Many people have commented that the Lanczos algorithm is much better at resizing footage than what adobe could do. Also TMPGenc has an excellent reputation and I had found this produced better results than the mainconcept one used by adobe.

I was very happy with my workflow but now I have CS5 I cannot frameserve from this to virtualdub as the frameserver does not support the 64 bit platform at the moment. I could make an intermediate lossy file and then open in virtualdub and frameserve to TMPGenc but this will eat up my hard drive space!

After looking through many possibilities I read about the CUDA GPU support and how it uses the lanczos resize algorithm. I unfortunately don't have an nvidia graphics card but have now just ordered one. I am hoping that this will produce a similar quality SD mpg without all these extra steps and complications!

Can anyone confirm whether the lanczos is used when using CUDA and maximum render quality is ticked?

Has anyone found CS5 to produce a better HD to SD conversation?

Should I see 2 line black vertical lines on the sides on my TV when the footage is converted from HD to SD when my HD footage naturally fills my TV screen!? (I have read the other thread on this but still cant get my head round it!)

[Mitch Hunt]

For more information on scaling in CS5, check out this blog post. The scaling quality has improved in CS5, especially with interlaced material and a MPE capable GPU. If you don't have one of the accepted GPUs, make sure and turn on maximum render quality.

You may also want to check out the workflow involving HD2SD and HCenc. Here's a video tutorial. I have CS5 and still use this method on many projects because it produces superior results.

BTW, a new frameserver for CS5 is nearing completion. I can post a link here when it comes out if you would like.

[Zoran Vincic]

Mitch, I'll be free to correct one thing you said.

Be sure to turn on maximum render quality even if you have a supported nvidia GPU.

Not so long ago we had a discussion here regarding Premiere's usage of GPU and the difference between direct and queued export. There was several different theories that were presented and the discussion ended but I was still left scratching my head about some things which weren't so clear so I did an experiment this weekend. Let me say that the results are interesting. I will compile and present them in a separate thread.

For now let me just say that even if you're using a GPU in Mercury engine and you're exporting via a queue and Media Encoder, you will need to >>enable MRQ<< if you want maximum quality.

I think that Harm stated that you do not need to enable MRQ if you have a supported GPU and you're exporting with Media Encoder, but my tests show that it's not true. That method will yield a lower quality export that is almost identical to an export I got with software Mercury Engine and without MRQ enabled.

However, if you're using a GPU and you're exporting directly from Premiere, then it doesn't matter, you get a identical (and I mean identical, not almost identical) export both with and without MRQ.

Let me just add that my tests involved scaling from 1080 25p to 576 25p.

I will explain all the details on how I did the test in a day or two in a separate thread.

[Steve Sykes]

Originally Posted by Mitch Hunt

For more information on scaling in CS5, check out this blog post. The scaling quality has improved in CS5, especially with interlaced material and a MPE capable GPU. If you don't have one of the accepted GPUs, make sure and turn on maximum render quality.

You may also want to check out the workflow involving HD2SD and HCenc. Here's a video tutorial. I have CS5 and still use this method on many projects because it produces superior results.

BTW, a new frameserver for CS5 is nearing completion. I can post a link here when it comes out if you would like.

Thanks Mitch for your information. I had read the adobe blog but found it unclear as to explain what resize process happens when MRQ is enabled when using a CUDA GPU. Does it go back to using a variable-radius bicubic algorithm or use the Lanczos 2 low-pass sampled with bicubic?

In my personal research and findings Lanczos 3 has produced very good results but I don't really know the difference between Lanczos 3 and Lanczos 2 and if a variable radius bicubic is as good as either of these!?

I hope I haven't foolishly spent money on a new card that doesn't actually make this process any better - at least my blu-ray encodes will be faster!

Thank you for the tutorial I have used some of those tools in the past but I'm limited by my hard drive space and am therefore very interested in the new frameserver for CS5! I will spent some time having a look at the examples in the tutorial and then ask you some further questions later.

[Steve Sykes]

Originally Posted by Zoran Vincic

For now let me just say that even if you're using a GPU in Mercury engine and you're exporting via a queue and Media Encoder, you will need to >>enable MRQ<< if you want maximum quality.

I think that Harm stated that you do not need to enable MRQ if you have a supported GPU and you're exporting with Media Encoder, but my tests show that it's not true. That method will yield a lower quality export that is almost identical to an export I got with software Mercury Engine and without MRQ enabled.

However, if you're using a GPU and you're exporting directly from Premiere, then it doesn't matter, you get a identical (and I mean identical, not almost identical) export both with and without MRQ.

So is the output sent via queue to the Media Encoder with MRQ enabled better than exporting straight from Premiere? Is the software render with MRQ enabled better than or identical to the GPU render? I realise that GPU will improve playback performance and be much faster but I have no comfirmation that it is better than the software encode with MRQ enabled. Can anyone clarify this officially or have seen an improvement in their renders?

[Ann Bens]

Some background on scaling:
some details about scaling in Premiere Pro CS5 Premiere Pro work area
Some background on CUDA:
Adobe Forums: Mercury, CUDA, and what it all means
Frameserver for CS5:
Adobe Forums: Debugmode Frameserver for CS5 available...

[Randall Leong]

Originally Posted by Steve Sykes

So is the output sent via queue to the Media Encoder with MRQ enabled better than exporting straight from Premiere? Is the software render with MRQ enabled better than or identical to the GPU render? I realise that GPU will improve playback performance and be much faster but I have no comfirmation that it is better than the software encode with MRQ enabled. Can anyone clarify this officially or have seen an improvement in their renders?

Software encoding with MRQ enabled will not be any better (quality-wise) than exporting. This is because software encoding, even with MRQ on, still uses bicubic resizing ratler than Lanczos2 resizing. Bicubic resizing works best if the Pixel Aspect Ratio (PAR) of both the source video and the encoded video are equal or near-equal to one another. Bicubic works rather poorly if the PAR of input and output are significantly different from one another.

[Steve Sykes]

Originally Posted by Ann Bens

Some background on scaling:
some details about scaling in Premiere Pro CS5 Premiere Pro work area
Some background on CUDA:
Adobe Forums: Mercury, CUDA, and what it all means
Frameserver for CS5:
Adobe Forums: Debugmode Frameserver for CS5 available...

Thanks for these links. I have a lot of reading to do and didnt realise that Debugmode had just updated its software - will have to try it out! Many thanks indeed.