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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 :)

What is DVCPro 720 exactly?

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If I output something at 1080 with DVCPro 720 is the image going to be softer? Is it somehow shrinking to 720 and then uprezzing to 1080? It seems like it should only be a bit rate and not a resolution change if going with DVCPro 720. Anyone know about this?
 
DVC Pro is the Panasonic HD format. It's a standardized codec and it's good, but ProRes is better. I'd go out to it before DVC Pro, unless you're going out to tape.
 
is DVC Pro 720 the same as "DVC Pro HD"?
 
I have successfully output from Shake at various resolutions using DVCPro 1080 and DVCPro 720 - it does seem to mostly be a bit rate setting.

However, I'm not sure I would recommend doing so. The codecs were designed with specific frame sizes in mind. And Shake is capable of making all kinds of weird non-standard Quicktimes, even ones that are not playable. So, again, I wouldn't do it.

Why not use DVCPro 1080 for 1080 stuff, and 720 for 720 stuff? Or, as suggested, ProRes? Or if this is for web/ftp/etc, a codec designed for that, like h.264?
 
From RedRushes DVCPRO 720 is the only option offered. It looks very soft if you output 1080 with the 720 codec. I don't think its shrinking, but as the previous posters said, the bit rate probably isn't high enough to handle 1080.
 
Dvcpro HD is 960x720. Not sure about the 1080 pix but I imagine it is also a stretched display.
 
DVCPRO-HD has non-square pixels for both 720p and 1080i modes. 1080p is not officially supported within the spec, however some cameras will encode true 24p into the 60i carrier and likewise, most NLE software these days will extract it.

For DVCPRO-HD at 1080, it's 1280x1080 for 29.97fps and 1440x1080 for 25fps.
 
Jeff Kilgroe said:
DVCPRO-HD has non-square pixels for both 720p and 1080i modes. 1080p is not officially supported within the spec, however some cameras will encode true 24p into the 60i carrier and likewise, most NLE software these days will extract it.

For DVCPRO-HD at 1080, it's 1280x1080 for 29.97fps and 1440x1080 for 25fps.
Click to expand...

so what happens when we encode 1920x1080 with DVCPro 720 in RedRushes?
 
I guess my posting was a little vague. What I'm asking is, what does setting DVCPro720 in red rushes or redcine actually do? It doesn't do any scaling or conversion to rectangular pixels. It must just b a bit rate limit, right? I guess it doesn't have enough size for 1080 square pixel output. The image comes out really soft.
 
OK, I just tried it... Because DVCPROHD720 implies that it's DVCPRO-HD @ 720p resolution. There is no bit-rate options here. DVCPRO-HD is 100Mbps.

It is creating a 720p @ 60Hz DVCPRO-HD video file, no matter what. However, it's breaking DVCPRO-HD spec if I feed it anything other than a 1280x720p scale of my R3D to output.

Now what is really weird, is that I chose DVCPRO720 as the output codec and I did a half-high debayer from a 4K 16:9 clip. Scaled to 1920x1080. The output file created is reporting as a DVCPRO-HD 720p60 format. But it claims the image inside is 1920x1080. It loads into the QT player as 1920x1080, QT player is scaling it, just as it would scale 960x720 to 1280x720. This file is out of spec because it shouldn't be allowed to specify 1920x1080 for the output with this encoded resolution.. It does look soft and crappy, obviously because it's scaled. The encoder seems to be crap too.

When I set my output scaling in RedRushes to 1280x720, it once again encodes as 960x720 and it plays back with the proper 16:9 ratio in QT player. This appears to be a properly encoded DVCPRO-HD 720p file.

If I scale to 960x720 in RedRushes and tell it to stretch the frame to the output size, that gives the proper raster size, but... It no longer plays back with the proper aspect ratio in the QT player. Otherwise it's the same as above.

All three files I generated are the exact same size.

If I load the files into Final Cut...
All three clips work just fine. The 960x720 clip displays with the proper 16:9 aspect ratio, even though it's mis-labeled as having a 1:1 aspect ratio. The 1080p labeled clip should not work, but it does.

If I load the files into Premiere CS4...
I create a new project and choose my format as DVCPROHD 720p60
The 960x720 clip loads into the viewer and onto the timeline with the proper 16:9 aspect and works as it should. The 1280x720 clip performs the same, I'm not seeing a visible difference between the two on closer inspection, and they should be the same as the file sizes are identical. It's just that one is mis-labeled as having a 1:1 960x720 output because that's what was set in RedRushes.

Now, the 1080p labeled clip when in CS4 comes in stretched to 1920x720. Otherwise it works properly.

So, it seems that the DVCPROHD output in RedRushes (and presumably the other Red tools) is buggy and should be avoided. The image output quality is horrible anyway. Stick with ProRes. The DVCPROHD output here also only outputs 720p @ 60Hz. So that's not very useful for most RED footage. But if you do want to use it and have DVCPROHD 720p60 for off-lining or dailies or whatnot, set your output scaling to 1280x720 and the DVDPROHD encoder will itself re-size to 960x720 and will mark the file for 1280x720 playback as it should be.
 
Thanks for the Test, Jeff!
DVCPROHD could be a chance in a Red-P2 (720p) production, but no chance in a RED workflow. I supposed PC users needs a codec as Prores.

Thanks again.
 
Is it labelled as 720p/60 but the frame rate is really 23.976? Is it adding a 2:3 pulldown to make it 59.94 or is it really just a label issue?

Michael
 
MichaelP said:
Is it labelled as 720p/60 but the frame rate is really 23.976? Is it adding a 2:3 pulldown to make it 59.94 or is it really just a label issue?

Michael
Click to expand...

if he makes a QT movie out of redrushes encoded as dvcpro 720/60,

opens it in QT player and hits 'show movie inspector' on the file,

won't that tell if the file is at 23.976 or 59.94 and if it's 960x720 or 1280x720?
 
DVCproHD 720p is as it states, 720 pixels high, progressive scan (progressive is another debate!) so forcing the height to 1080 will not produce good results. I'm curious as to why you need 1080 for what you are doing at the stage you are at. I would guess 720 will do the job and wouldn't obsess on a 1080 product if it's going to cause a lot of extra work.
In the end you can experiment with transcoding your final raw files to multiple 1080 formats, but for rushes, 720 should look great.
Your 720 files will be 720 h x 960 w because DVCproHD uses rectangular pixels that will be stretched out to a 720 h x 1280 w proportioned frame. (1280x720 is the proper way to say it).
The reason for the rectangular pixels has to do with how these new HD formats have been made affordable and available on prosumer cameras.
 
there's some confusion here between the rectangular issue which is pixel width (960 vs 1280) and your real question of pixel height, forcing a 720 product to 1080. So, no you will not get good results forcing a codec designed for 720 high to 1080 high. It's not just the bitrate, think of it as forcing an image to scale itself up 150%!!
The rectangular issue is not a problem, although not perfect, the codec was designed to stretch out to proper 16:9 display without noticeable quality loss, this is VERY different from increasing the HEIGHT from 720 to 1080!!
 
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