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August 6th, 2007, 03:23 PM | #1 |
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HV20 HDV compression vs. Intensity JPEG codec?
Has anyone here been able to compare the the image quality of the compressed footage of the HV20 compared to using the HV20+Intensity capturing with their JPEG compression codec? Would the JPEG codec produce better image quality? I would like to start some live capture straight to hard drive without using a RAID and using a compression codec, but if the HV20 can capture just as good image quality on tape as opposed to having the camera hooked to the Intensity card, then I don't want to bother getting an Intensity card.
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August 6th, 2007, 09:21 PM | #2 |
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In my experience, the JPEG codec wasn’t that much better! Even thought I imported at full raster 1920x1080 (rather than HDV's 1440x1080), the JPEG codec's macro blocks diminished the potential benefits. It simply wasn't what I was hoping for - shooting HDV to tape was more worth than the JPEG codec.
However... There *is* a night and day difference between the HDV (or JPEG) codec and Apple Prores 422. Incredible. Think of the Prores codec as being uncompressed, and you get the idea. Apple say's you don't need RAID either. HDV in the Canon HV20 is the best implementation of HDV that I've seen - beats the big 3-chip HDV Sony Z1U and FX1 cameras. However, having the digital uncompressed input option (the Intensity card) certainly has its useful aspects. JPEG codec = not very good. Intensity = great (with decent codec). If you use a PC, the comparable codec to Apple Prores 422 is Avid's DNxHD codec. http://www.avid.com/dnxhd/
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August 7th, 2007, 01:21 AM | #3 | |
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Quote:
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August 7th, 2007, 01:36 AM | #4 | |
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Quote:
Blackmagic 8-bit MJPEG vs CineForm HD |
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August 7th, 2007, 07:50 AM | #5 |
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Hey Serge, thanks for providing the link, well worth reading and very informative. I know that I'll be getting NeoHDV perhaps this week - so it's good to know that Cineform supports capturing from the Intensity. So it looks like the JPEG codec that comes with the Intensity is just not quite good enough but does anyone know of other compression codecs that will work with the Intensity? Can any codec be used the Intensity such as whatever codecs have been installed by Sony Vegas 7e?
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August 7th, 2007, 08:08 AM | #6 |
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DNxHD only works with Avid in that you can edit in Avid. DNxHD isn't an open standard codec like Cineform.
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August 7th, 2007, 12:06 PM | #7 |
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Thanks David, wasn't sure if it was. I stopped using PC's for editing just before it came out.
Then Cineform is your best bet Nathan, for sure. Stay away from those JPEG codecs!
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August 7th, 2007, 01:29 PM | #8 |
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I do not agree about the jpeg codecs. I tend to find them pretty good compared to HDV. I'm not sure what you are doing to get them to look so bad but for me they look just as good as any DCT based HD tape format if not better. About the only tape format I would say that looks better is HDCAM SR. Of course Cineform is slightly better but jpeg is not bad either.
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August 8th, 2007, 02:02 AM | #9 |
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I've always set mine to capture at 100%, and they're still.. awful for me. It could be me or my settings, but everything else works well - the JPEG codecs always have poor compression in the areas with the most similar colours - (i.e. the blacks).
I did an HD-SDI uncompressed capture, then an HD-SDI capture to JPEG.. and, quite a difference. Others have said JPEG was very good, so, like Thomas might suggest, test capture yourself Nathan, or do export tests, and decide what you like. Regardless, the Intensity card works very very well. Codecs will come and go – the HDMI spec will be around for a while.
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August 8th, 2007, 12:15 PM | #10 |
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Motion JPEG, especially Apple's implementation, can be very good, and quite fast. Because it is storing each frame uniquely, it doesn't suffer from the inter-frame artifacts of MPEG-2 HDV. It can also be set to use a much higher data rate.
That said, with a reasonably fast computer I can't see any reason to not go with a modern codec like ProRes, DNxHD, Cineform or the like. JPEG and MPEG are technological dinosaurs. |
August 11th, 2007, 03:37 AM | #11 |
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HDV blocking artifacts in black minimization
I think I found a way to minimize blocking artifacts in HDV blacks. I would like to explain and if someone try it, let me know.
1 - put the same m2t footage aligned in two video tracks in Adobe Premiere. 2 - in the upper track apply gaussian blur and adjust between 4 and 6. (adjust looking the blacks) 3 - in the upper track apply arbitrary map and adjust between -5 and -1 (adjust looking the blacks) 4 - in the upper track apply luminance key (adjust the key to keep only the blacks of the upper track over the lower track, be carefull to not get color fringing in key edges) 5 - render to uncompressed. The goal is to minimize the blocking artifacts in the blacks where HDV compression is more visible. If someone try this, let me know. Thanks. |
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