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Old July 29th, 2007, 10:45 AM   #1
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Getting True 24p off the HV20

So I get this document the other day from a very well respected technical advisor in CA and I think I've read it about 30 times now. I've gone through all these steps and yet it makes no sense to do things this way. Seems to me you could just import the footage directly into FCP6 and set your sequence to the Apple Intermediate Codec. Plus, even though I had been importing footage as HDV and then rendering it as Uncompressed 8-bt 4:2:2, I was able to throw that uncomp'd clip into Cinema Tools and do the reverse telecine without issue.

I'd like for you all to read this doc and see if you can make any sense out of it. I'm very interested to hear everyone's thoughts on the matter.

---------------------------

The way to get True 24P off of the HV20

Getting a true 24p file from the HV20 can be a bit of a bear, but it is doable. Again, we are using a cheap consumer toy for professional purposes so of course, it's not going to be super easy. It’s kind of like hot-rodding a VW bug into a race car. It can be done, but elitists will look down on you, and tell you to buy something real.

The typical edit system that I use is Final Cut Pro on the Mac, and the following is a mac based workflow which has the kinks ironed out in it. The camera shoots 24p 1920x1080, but records it as 1440x1080 and the 24p is pulled-down into 59.94i. So the steps are first, to capture the mpeg from the camera, transcode it into a format that is pulldown friendly, and perform the pulldown.

The first thing to do is download a toolkit from the developer section of the apple.com website. Go to this link: http://developer.apple.com/hardwaredrivers/download/ and download an item called Firewire SDK23. It's a couple of tools for working with the firewire port on your mac. The only program we are interested in is DVHSCAP.

DVHSCAP is a tool originally designed to work with D-VHS machines. It allows your computer to capture MPEG-2 streams over firewire. So, you can plug in your HV20, fire up DVHSCAP, press play on the camera, and press record in the program, and you can capture a stream. The annoying thing is that in 24p mode on the camera, you have to capture each clip separately.

So, after crash-recording each clip separately, you will have a folder with a bunch of M2T files in it (mpeg 2 transport streams). These are encoded data streams where your video, audio & timecode live.

The second step is to download the ever useful shareware program MPEG Streamclip. It's on versiontracker.com and is a free download. Open this program and use it to transcode your M2T files into Apple Intermediate Codec (AIC) files. Keep them as 1440x1080/59.94i. Save them into another folder. The reason to go with AIC is because AIC is the same resolution as your captured footage, but everything is encoded as an I-frame (all frames are separate, instead of linked like an MPEG file). If you transcode everything as HDV 1080/59.94i then the frames would be linked to one another and you cannot perform pulldown on them.

Third step is to open Cinema Tools, which is packaged with Final Cut. This is the annoying part. You have to open your AIC files in quicktime player or other viewer and watch the first couple of frames, frame by frame, watching which frames are whole frames and which frames are half of one frame and half of the next frame.

You have five selections for your start frame. AA, BB, BC, CD, DD. AA, BB, & DD are progressive frames, the first field is from one frame and the second field is from the same frame. BC & CD are frames that hold half of one frame and half of another. Look at the edges of moving objects and you can see interlaced scan lines. Find out which frame your first frame of video is. File:Open Clip... in Cinema Tools. Select the frame cadence for that particular clip and perform a reverse telecine on it.

Keep going until you have finished all of your clips. At this point the footage will be Apple Intermediate Codec 1440x1080/24p files. Nice. Now would probably be a good time to put a bag over your head and scream. It's not easy or fun, but the images you can get in the right circumstances from this camera are astonishing. The only problem is that the C frame has to be created out of two half frames (BC & CD), so sometimes the quality of the C-frame can suffer. This quality drop is compounded by HDV. So, it’s a nice toy that you can get something great off of occasionally. The camera costs $1000. Cheer up.

At this point you have a close relative of what is known as the universal master format, 1080p/24. You can render out DPX files, play the footage out via your Kona card into an HDCAM or HDCAM-SR deck and record true 23.98p, or figure out some sort of software way to incorporate the footage into your timeline.

Good luck
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Old July 29th, 2007, 02:22 PM   #2
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This thread seems appropriate to ask this technical question and I've read all the forums on this 24p stored within a 60i data stream - but I still don't fully understand, but maybe I do. :o)

Since it is a 60i data stream (hence 30 frames) - does this technically mean that each of those 24p frames are stored as two interlaced fields that must be put-together to create a single full frame (called a progressive frame)? And then those 6 extra frames (that total 30) are thrown away since we have to end up with only 24 frames???

And a product like NeoHDV is doing exactly that...correct?

If all this is true, then I can see where some could say (or argue) that it's not TRULY a full progressive frame captured ALL AT ONCE (like a digital camera does)...but then again, I can also see how it can still be considered a true progressive frame no matter how it may be digitally sliced up and stored technically (with 2 interlaced fields or 2000 interlaced fields), as long as that progressive frame can be digitally put back together correctly - then the end result is a full progressive frame (just like digital camera captures).
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Old July 29th, 2007, 02:54 PM   #3
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First off, this is a Mac only solution. I use a Mac, but, since many/most own a PC, it's not the only way to do it, so the thread is mis-named IMO.

Second, what a labourous way to do go about getting 24P. There are other threads that are here already that explain it more simply, and do it with less steps.

Capture to computer, and if you have FCP6 and compressor, you're set.
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Old July 29th, 2007, 04:01 PM   #4
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Capture to computer, and if you have FCP6 and compressor, you're set.
That's what I thought after reading this. I guess what I'd like to know is exactly how the sequences are being setup in FCP6 in order to capture from the HV20 properly. Are you capturing in HDV or Apple Intermediate Codec, or Uncomp'd 8-bit 4:2:2, etc. (and are you going out of the camera via FW?)

Plus, I'd also like to know what solution (besides things that cost $10k+) people are using as far as storage goes in order to speed things along. All rendering and real-time playback (especially in color and motion) takes forever. I've got a dual 2ghz G5 with 3GB of RAM and (2) SATA drives (1 for the apps and 1 for storage).

I'm just trying to figure out the best way to shoot (settings wise) on this camera, and the best way to import and work with the footage (basically so I get the best picture quality with the most flexibility in post). Ever since I got this camera I've been trying to figure this out and everyone seems to have a different opinion (which they all seem to term as hard fact).
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Old July 29th, 2007, 04:45 PM   #5
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Joshua, there is a plethora of information on the best workflow and settings for the on this forum - best options for shooting for post, etc, etc. I think it's truly up to you to test and decide for yourself - you said it already - everyone thinks they're way is the right way.

By asking the question again, you'll simply get the same answers again. It's all variables: project length, project importance, post options, software choices, storage options, necessity of speed vs. quality, etc.

What are you looking to do with the HV20 footage you shoot? What's it for? Budget?
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Old July 29th, 2007, 04:48 PM   #6
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Good god

Or...............you could use JES De-Interlacer to do the pulldown for you automatically without the need for all of this.

Just drag you HDV Clips in to the window, choose "Inverse Telecine" blah blah and choose your encoding format. DONE.
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Old July 29th, 2007, 05:11 PM   #7
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What are you looking to do with the HV20 footage you shoot? What's it for? Budget?
Yes, I know that and I've read most all of it over the past few weeks on this and other forums. The problem is, no one is saying, here's the settings to import into FCP. I am shooting in CineMode at 24p on high quality Panasonic MiniDV tapes. I spoke with Canon and was told that yes, I would get higher resolution images if I went straight out the HDMI port. I thought about this and looked into outboard units that would allow this. Unfortunately, HDMI doesn't carry timecode (at least not properly) and is mostly used to directly hookup the camera to an HDMI compatible television. So, I'm assuming that everyone is going out via FW. If this is so, what are the sequence settings in FCP (HDV, etc.)?

Also, I have hardly seen any posts regarding the other subject, which is disk arrays and which ones are being used. I'm not interested in spending $10k on a fiber channel solution, but I am interested in not spending hours waiting for color to render 2 minutes of footage (2:17 of HDV took 1 hour and 23 minutes). I know that HDV is an MPEG file and heavily compressed. One person suggested that I do all my importing via HDV and cut everything in FCP and then change the sequence settings to Uncomp'd 8-bit 4:2:2 prior to doing any rendering. Well, sure enough the rendering times are sped up a bit, but the file sizes are so huge that the disk I have in the system doesn't seem to handle real-time playback.

I come from the pro audio world and if someone asks me what the best way to record audio is, I tell them to use a Lynx Aurora16 converter at 24/96 into ProTools HD 7.x. It doesn't matter if they are recording on location, or in a studio. That's the best way to work with audio. There must be some sort of similar plan of action for video or no one would ever be compatible with anyone else. Isn't there an industry standard way to do this, whether it's for pro or home use? It shouldn't matter what I'm shooting. I would like to know about importing from the camera to FCP6 the best way possible (whether that's FW or buying an outboard box, KONA card, etc.). I would also like to know about my storage options and what will really work (I don't want to spend a few grand to find out that it didn't help very much).
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Old July 29th, 2007, 05:25 PM   #8
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I come from the pro audio world and if someone asks me what the best way to record audio is, I tell them to use a Lynx Aurora16 converter at 24/96 into ProTools HD 7.x. It doesn't matter if they are recording on location, or in a studio. That's the best way to work with audio. There must be some sort of similar plan of action for video or no one would ever be compatible with anyone else. Isn't there an industry standard way to do this, whether it's for pro or home use? It shouldn't matter what I'm shooting. I would like to know about importing from the camera to FCP6 the best way possible (whether that's FW or buying an outboard box, KONA card, etc.). I would also like to know about my storage options and what will really work (I don't want to spend a few grand to find out that it didn't help very much).
I hear you... the HV20 is a cheapo/yet great value camera. To use it to do "true HD" is a hack itself, yet, a really darn good hack. The HD video world is sort of going through what the audio world went through several years ago - the change from analog to digital. HD is changing quickly - interlace is a carry over from the analoge beginnings of video.. it to will weed itself out, but for now, it's changing kind of up in the air. However, armed with an HDMI toting HV20, you've got some great options.

The BEST WAY to get the HIGHEST quality HD out of the HV20 is using products by Blackmagic Design - there are 3 options. Ranging in price from low to high, there is the 'Intensity' card, the 'Itensity Pro' or the 'Decklink HD Extreme' - I own the last one.

Capturing via HDMI a LIVE (not playback of HDV) signal through one of those cards to a computer via FCP6 - the best codec is Blackmagic Design Uncompressed 8bit 59.97i at 1920x1080 full raster. You'd need a 4-hard drive RAID to do this. The next best option is the Apple ProRes 422 HD codec at 59.97i at 1920x1080.

From these two extreme codecs, you'll have the best and then second best, hands down.

Then you can do the Compressor revese telecine option.

Now, the Intensity products are PCIe only - Intel Mac Pro only, no Mac G5's :(. The Decklink HD Extreme I believe has a PCI-X option, but it's more expensive. And to use the Decklink HD Extreme option with HDMI, you'll need to convert the 'consumer' HDMI signal to the professional HD-SDI signal.

Quote:
Originally Posted by Joshua Aaron View Post
One person suggested that I do all my importing via HDV and cut everything in FCP and then change the sequence settings to Uncomp'd 8-bit 4:2:2 prior to doing any rendering. Well, sure enough the rendering times are sped up a bit, but the file sizes are so huge that the disk I have in the system doesn't seem to handle real-time playback.
Yes, this is what I do for HDV projects that I wish to 'upscale'. I import and then edit a sequence in HDV, then import the timeline into a higher end codec format, much like I described above, and apply all my filters there. Then I render, and export. Yes, the file sizes increase (I have a 2 hard drive raid for a scratch disk) and no, this doesn't deal with 59.97i to 24P if you haven't already in a prior step.
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Old July 29th, 2007, 10:33 PM   #9
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The BEST WAY to get the HIGHEST quality HD out of the HV20 is using products by Blackmagic Design - there are 3 options. Ranging in price from low to high, there is the 'Intensity' card, the 'Itensity Pro' or the 'Decklink HD Extreme' - I own the last one.
The BlackMagic DeckLink HD Pro PCI-X seems like a great solution and doesn't break the bank. I just read through the entire manual as well as all the info on their website. What I don't understand are a couple of things:

1. Do I remove the AGP ATI video card in my computer when I go to install the DeckLink (and if so, how do I view my computer stuff on my Cinema Display (or am I just being silly and this is a secondary add-on card that allows for all the features and is used in conjunction with the ATI card)?

2. It states in a few places that the DeckLink handles the processing of all the RT effects and rendering. Does this mean it completely offloads all of that from the computer's CPU and it's all in real-time (only dependent on the speed of the disk array)?
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Old July 29th, 2007, 11:37 PM   #10
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Since it is a 60i data stream (hence 30 frames) - does this technically mean that each of those 24p frames are stored as two interlaced fields that must be put-together to create a single full frame (called a progressive frame)? And then those 6 extra frames (that total 30) are thrown away since we have to end up with only 24 frames???

And a product like NeoHDV is doing exactly that...correct?
Look up 3-2 pulldown. The 24p frames as stored as 3 fields, then 2, then repeated 3,2,3,2.., this places 24p in 60i. So yes NEO HDV/HD/2K and all the CineForm products understand this and extract the core 24p data on the fly.
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Old July 30th, 2007, 01:31 PM   #11
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I spoke with BlackMagic this morning as well as Avid and basically for Mac, Avid doesn't make any sense at all. BlackMagic told me that the HD Pro PCI/X card we've been discussing is nothing more than an i/o card and doesn't do anything to help with offloading the processing of RT effects or rendering. They said that all depends on the speed of your computer's processor, nothing more.

Is this true? Is there anything besides plugging in outboard decks/components that makes the HD Pro card something to look at purchasing?
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Old July 30th, 2007, 01:43 PM   #12
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The Intensity Pro offers analog I/O, that seems like a good deal for the extra $100. The time of "accelerator" cards has almost gone away, AJA & Blackmagic offer primarily I/O solutions (and very good ones.)
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Old July 30th, 2007, 01:48 PM   #13
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That's correct - it's an IO card. And a very valuable one - uncompressed HD I/O at the level that the Blackmagic Design team provides at the price they sell them at was unheard of a year and a half ago. They've revolutionized the system.

No processing of the image, and it goes only as fast as your RAID and your CPU - that's all up to your computer and GPU. However, it magically allows output of all the HD formats avaliable to an HD or SD monitor (which is useful)! Right now, there's pretty much no other way to do with it out one of these cards - unless you spend $20k on a 'higher end one' - not that it'd offer anything more you'd need.

However, with the Decklink card you'll need the Convergent Design nanoConnect product to import HV20 footage as digital - it's an HDMI to HD-SDI convertor to allow you to pull in a digital signal to your computer (unless the Decklink card you're looking at now has HDMI in as well). I own the nanoConnect - poor product design value (feels homemade) , but it does exactly what you'd expect and does it well.

I have no idea how the card goes into the G5 Mac - I own an Intel based Mac Pro.
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Old August 2nd, 2007, 01:45 PM   #14
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I'm Sorry but this is INSANE -

The 24F on the XL-H1 at least looks progressive
this "24'' is all interlaced
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Old August 2nd, 2007, 02:10 PM   #15
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I'm Sorry but this is INSANE -

The 24F on the XL-H1 at least looks progressive
this "24'' is all interlaced
Sorry....but this is just not true...If you do it right, and it's not hard to do, you will get true 24p. 24 continuous progressive frames per second with no interlacing whatsoever. I have witnessed it first hand and went through a clip and investigated each frame to confirm this.
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