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-   -   Real 1080 24p @ 4:2:2??? (https://www.dvinfo.net/forum/sony-hvr-v1-hdr-fx7/80520-real-1080-24p-4-2-2-a.html)

Ron Little May 4th, 2007 05:47 PM

Aspect HD cost $500 and has no card to capture with. Intensity cost $250 and can capture uncompressed hd to your hard drive and capture 4-2-2 and motion jpeg . That is a nice little bonus.

Heath McKnight May 5th, 2007 06:30 AM

All of CineForm's products can be captured via Firewire. No need for a card, though I'm sure you can buy one.

heath

Ron Little May 5th, 2007 06:55 AM

I will probably end up with both anyway.

I am waiting until CS3 comes out to see what kind of support they are going to have.

I captured the same clip three ways Black magic via HDMI, Mjpeg via Firewire and mt2 via Firewire, all are from tape. They all look similar.

Today I will shoot and tape a clip for a better test.

Heath McKnight May 5th, 2007 06:58 AM

Great, Ron! I'll email Chris again.

heath

John Bosco Jr. May 5th, 2007 10:40 AM

Quote:

Originally Posted by Heath McKnight (Post 672924)
I understand, actually, that the Intensity captures it as 4:2:2 1920x1080 and makes the HDV footage look great. However, if you can bypass the HDV codec, you're doing better, obviously.

Either way, I love working with HDV and plan on really using the V1u more often. I'm still a Z1u/FX1/DVX100a user.

heath

Actually, Intensity is capturing the HDV footage using up greater disk space with no better quality. If this workflow is one you desire than great, but don't try to tell us that HDV footage looks better captured from the intensity card than firewire because it doesn't. At best, it looks the same. Captured HDV footage can be up-rezzed through output. It is silly, in my opinion, to recompress it during capture.

For live, then I agree; it is currently the best solution for full HD from the V1. But for tape, you're best just capturing the footage through firewire or importing/transfering the files off of the Sony hard drive if you have that option.

Stephen Armour May 5th, 2007 04:00 PM

Quote:

Originally Posted by John Bosco Jr. (Post 673317)
Actually, Intensity is capturing the HDV footage using up greater disk space with no better quality. If this workflow is one you desire than great, but don't try to tell us that HDV footage looks better captured from the intensity card than firewire because it doesn't. At best, it looks the same. Captured HDV footage can be up-rezzed through output. It is silly, in my opinion, to recompress it during capture.

For live, then I agree; it is currently the best solution for full HD from the V1. But for tape, you're best just capturing the footage through firewire or importing/transfering the files off of the Sony hard drive if you have that option.

I uprezzed to 1920x1080 (from 1440 HDV) using CF, and side-by-side it looks much better than the original HDV. To make it harder, I was doing some very red direct sunset, with dark foreground and clear skies. Huge gradient range. In the CS3 beta, the uprezed, 10-bit Prospect output, even from the HDV, is very nice indeed, and from an editors viewpoint, it blows the original out of the water.

If uprezed compressed video looks better using CF, you can be sure that capturing directly from the HDMI port via Intensity and CF, will be SPECTACULAR in comparison. No way it couldn't. Not to mention being upped to 10-bit for much smoother color gradients. You can't get that without the uprez and 10-bit conversion. CF really is good.

Thomas Smet May 5th, 2007 06:03 PM

Well it all kind of comes down to the decoder.

With a camera there is a decoder chip designed for high quality decodes of the mpeg2 stream. That stream is decoded and upconverted and sent out the HDMI port to a new format of your choice.

Most NLE systems on the other hand depend on software decoders to decode the mpeg2 file which it puts in a decompressed buffer. Some NLE's work with this decompressed RGB buffer.

HD mpeg2 can suffer from bad encoders and decoders just like DVD's can. In the world of mpeg2 no two encoders and decoders are exactly alike. With DV the format was pretty standard so it was safe to say that across the board DV was DV. Mpeg2 is very complex and sometimes some realtime software decoders may not do the best to reduce the macro blocks and recreate the RGB image.

The HDMI port may also do a better job at upconverting the signal because it wants to send the highest quality decoded RGB image to a HDTV.


In a lot of ways it follows one of the same arguments from Cineform which is that by capturing to their format the quality will hold up better. By using Cineform you are pretty much doing the same thing as HDMI expect Cineform uses it's own high quality decoder and saves the decoded results via firewire into their format. This has been known to sometimes give a little bit higher of quality because the mpeg2 is already decoded with the highest level of quality and put into a format that will hold up better to editing. It does this so the NLE doesn't have to use it's decoder which may or may not be the greatest.

I cannot confirm this for sure yet or not but the HDMI port may also be upconverting the chroma. Cineform already does it by interpolating the chroma and turning it into 4:2:2. Of course this isn't as good as raw 4:2:2 color but it helps a little. HDMI may also upconvert the signal to 4:2:2 to try to send the highest signal it can to a HDTV. So by capturing a HDV tape via HDMI it may tryt to at least smooth out the chroam so the edges are not jagged. Again I have not been able to confirm this. I do however know that this always helped me a lot with DV footage. I used to capture DV tapes of bluescreen footage via component to uncompressed and while there may not been any extra chroma detail the chroma was smoothed out so there were no jagged edges. This pretty much had the same effect as blurring the chroma channels in a NLE but then I didn't have to wait for it to render.

Heath McKnight May 5th, 2007 06:48 PM

John B.,

Converting HDV to 4:2:2 is a good thing, trust me. Besides, it's pixel-shifting 960x1080 to 1440, then you output and it pixel-shifts again to 1920 on those displays. And it's clean. I like working with captured footage at 1920 and it apparently looks great!

heath

Ron Little May 5th, 2007 07:17 PM

I have some clips captured from tape via HDMI and Firewire but I don’t know where or how to post it. Today I captured a clip uncompressed and rolled tape at the same time. So I can show you the same clip captured uncompressed and HDV.

Heath McKnight May 5th, 2007 07:22 PM

Can you upload it to an FTP? I might be able to put it on my .mac.

heath

Ron Little May 5th, 2007 08:10 PM

A one minute and thirty-nine second uncompressed clip is eleven point six gigs. So far all the send it sites max out at two gigs. I will have to cut it down.

Heath McKnight May 6th, 2007 08:35 AM

Ron,

Yowza! How about making it a 10 second clip?

Thanks,

heath

Stephen Armour May 6th, 2007 09:14 AM

Quote:

Originally Posted by Ron Little (Post 673476)
I have some clips captured from tape via HDMI and Firewire but I don’t know where or how to post it. Today I captured a clip uncompressed and rolled tape at the same time. So I can show you the same clip captured uncompressed and HDV.

Ron, are you compressing using BM's compression or not at all? I believe their codec has been compared to CF's and the latter came up much better in tests.

By the space you mentioned you used for capture, you'd easily save a bundle on RAID HDDs and then storage space by capturing via the HDMI port and using CF to very lightly compress those giant files! It seems from Cineform's own testing and that of others, you'd be hard pressed to see much of a difference in the quality of the final output, but would definitely be smiling at the amount you saved by using a premiere compression algorithm (even at a measly $500)!

Ron Little May 7th, 2007 09:43 PM

Sorry it took so long to get back internet connection down.

Yes I am using the BM’s compression codec. It looks good to me but I am not always the best judge. I would like you guys to take a look. I just have to find a way to get it to you. Maybe I should start with some pics.

Steve Mullen May 8th, 2007 05:03 AM

Quote:

Originally Posted by Heath McKnight (Post 673470)
Converting HDV to 4:2:2 is a good thing, trust me. Besides, it's pixel-shifting 960x1080 to 1440, then you output and it pixel-shifts again to 1920 on those displays.

heath

1) HDV is automatically converted to 4:4:4 inside your NLE so, if you are simply editing HDV, there is no advantage to decoding it before a frame is needed. (In fact, it's a waste of storage space and increases disk bandwidth requirements.)

If you are editing in FCP, or any Avid product, there is no advantage to not using native HDV editing.

2) The V1 doesn't use "pixel shifting" -- if it did H. rez. would be increased by only about 115%. Both H and V interpolation is used, which increases both H and V significantly -- to about 775-lines for each.

Since you have, at most, 800 pixels of H information it is a waste of storage space, disk bandwidth, and CPU computer power to "handle" 2X that number. A 1440x1080 path is more than enough rez.

(Remember, the V1 the CMOS chips are not "over-sampling" the HDV format the way HDCAM CCDS over-sample HDCAM. In fact, strictly speaking, they under-sample the HDV format.)

3) At the point where an anmorphic format (non-square pixels) is "converted" to 1920 (square pixels), "pixel-shifting" is not used. Simple scaling is used to "spread" the 1440 pixels over 1920 pixels.

The goal is to record the image before compression!

HOWEVER, it's not that simple. The CFHD codec itself is not the only thing CineForm has going. When Connect HD gets HDV via FW and is decoded -- and then converted to 4:2:2 -- really good upconversion math is used. So BEFORE the decoded image is compressed to CFHD, it is "enhanced" by the software in Connect HD. This is why CFHD may look better than letting FCP do the decoding.

Plus, you get the option of 2-3 pull-down removal. So although Aspect HD costs more than Intensity, it does more and it works on a laptop.


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