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June 7th, 2009, 03:14 PM | #1 |
Trustee
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When rendering pictures, can I go for a lower VBR?
I have about 1100 pictures for a slideshow that I am rendering out in Vegas. I want to include them on a DVD using ARCH 5, but it will be quite long and almost take up the entire single DVD (I don't want to go dual layered). I have Mark's Bitrate Calc and it works great, but I was wondering IF I can I lower the variable bit rate (VBR) for pictures -still images- will this retain better quality then with moving video at the same VBR? (if that makes sense)
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June 7th, 2009, 06:25 PM | #2 |
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What rates are you using? How long is it running? You should be able to keep the average rate low. The transitions will need more.
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June 7th, 2009, 07:31 PM | #3 |
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Are you saying that transition make a file size bigger or did I misunderstand? The project is huge, and I am in the middle of trying to pare things down to a smaller size so I can fit it all on one DVD. As I said, about 2000 stills images altogether as well as video. I have been putting transitions between the images, but if that is going to add to the render size (and probably time as well), I think I will take them out and just use dissolves instead...
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June 7th, 2009, 07:38 PM | #4 |
Inner Circle
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Location: Windsor, ON Canada
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The encoder in Vegas won't give you the kind of control you're looking for (i.e. different bitrates for different sections).
Transitions won't make a file bigger, only the overall length. Stick with the numbers you get from Mark's Bitrate Calc. I've been using it for a long time and it's never let me down. edit: Harold is correct about how VBR works. I was referring to (but forgot to mention) high-end encoders that have the ability to adjust these settings on a shot- by-shot basis. Last edited by Mike Kujbida; June 7th, 2009 at 10:45 PM. |
June 7th, 2009, 10:07 PM | #5 |
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David,
VBR gives different bitrates to different sections. It gives a higher bit rate to the areas that need it by taking away from other scenes that don't. A 2 pass render allows Vegas to do a better job of distributing the bits. Too bad it doesn't have a 3 pass render to squeeze more out of it. This is important if you have video and stills on the same time line. You can control the final size by keeping the pictures on the time line small (720x480 for SD) and the bitrate as low as possible (since you have so much content). You can determine that from the calculator but you can always experiment with the bitrate to see what you can do. Last edited by Harold Brown; June 7th, 2009 at 10:08 PM. Reason: added "for SD" |
June 7th, 2009, 11:46 PM | #6 |
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Use two-pass VBR.
low: 192 Kb/s avg. as explained below. max: 8000 kb/s should be ok. Either 9-bit or 8-bit DC coefficient. (Probably 8-bit). I think you should be able to get down to an avg. bitrate rate of about 1500 kb/s. Try a test render first of 20 pictures using some different 2-pass VBRs: 500, 750, 1000, 1500, 2000, 2500 kb/s and use these 6 tracks as 6 clips in a multi-clip DVD. Since most of the time, the image is static, the avg. bit rate can be quite low. So what you're really interested in is the quality of the transitions. Other trick is to use the half-D1 format (352x480 NTSC, 352x576 PAL) rather than the standard D1. The DVD player automatically shows the right aspect ratio during playback. Halving the number of bits encoded makes lower bitrates possible. There is no preset in Vegas for this format, but you can change it in the MPEG-2 encoder settings (Custom | Video | Width). In the Architect 5 you can set it in File | Properties | Disk Properties | Resolution. You will find half-D1 values in the drop-down resolutions shown. Dan. Last edited by Dan Bridges; June 8th, 2009 at 02:15 AM. |
June 8th, 2009, 11:38 AM | #7 | |
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Quote:
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June 8th, 2009, 12:09 PM | #8 |
Inner Circle
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June 8th, 2009, 03:53 PM | #9 |
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Yep, I had some flicker a couple of different times with my projects on just a couple of pictures and until I saw posts about it I could never figure out why it was doing it. It had never occurred to me that those pictures were much larger than the others.
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June 8th, 2009, 06:39 PM | #10 |
Inner Circle
Join Date: May 2005
Location: Windsor, ON Canada
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And if you still get flicker, try the Gaussian Blur FX with Horizontal set to 0.0 and Vertical to between 0.001 to 0.003.
Make sure this FX is applied before scaling the image (in Pan/Crop, for example). |
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