AVCHD editing slow on Vegas Pro 8.0b

Sebaz wrote on 5/24/2008, 7:16 AM

I have a fairly powerful machine by today standards without being extreme:

2.40 Ghz Intel Core 2 Duo
4 GB of DDR2 RAM (800 Mhz)
Intel D975XBX2 Motherboard
eVGA Nvidia 7950 GT graphics card with 256 MB of RAM
2 Western Digital Caviar SE with 16 MB of Cache (Video editing files are in the dedicated drive)

I'm running Vista Home Premium with SP1 (bought it with SP1 included and installed it from scratch). I checked that there are no unnecessary services running and the system is clean of malware, spyware and all that, I scan it often and make sure that it's clean.

However, when I load AVCHD files from my Canon HF100 in Vegas Pro 8 and play them from the timeline they play slow, depending on the action going on they might play at 7 fps and then maybe go up to 15 to finally stabilize at around 11, but it can go down again to even 5 fps. This is while having quality set to Preview (Full), and changing to Draft (Full) doesn't really make a difference. Setting any quality to (Half) will actually make it worse, I suppose because Vegas has to downscale on the fly.

This only happens when playing back from the timeline, if I choose the source file in either the Project Media or the Explorer tabs, they play at 29.97.

I checked my project settings, and everything matches the source files: 1920x1080, 29.97, upper field, pixel ratio square and color depth 8 bit.

My source files are 17 Mbps, but I tried older AVCHD files from a Panasonic SD5 I had, which were 13 Mbps, and the same happens.

Obviously there are no filters or any pan/crop applied to the events I'm playing.

I'm just wondering if it's that Vegas is slow for timeline playback, or if maybe I have something else installed in my system that is interfering with Vegas and making it play video so slow. Does anybody know if Vegas has its own internal codec engine for timeline playback, or if it relies on systemwide codecs for that?

I would think that with a dual core processor and 4 GB of DDR2 RAM my computer would be capable of handling AVCHD pretty well, so I think the problem might be somewhere else, but I hope somebody more knowledgeable can enlighten me.

Comments

UlfLaursen wrote on 5/24/2008, 7:57 AM

Have you tried to play back any HDV (m2t) files - you can download a few here to test. They are not as demanding as AVCHD, but could give you an idea, if they play:

Download from vasst.com

http://www.vasst.com/HDV/FX-1_images-Surfers.htm

VASST have this util that migth interest you as well:

http://www.vasst.com/product.aspx?id=bf3e2d5a-7c2e-4969-a8dd-7cee2cefba30

I have only tried to edit AVCHD on a quadcore as a test, and it went ok. This quadcore actually has the same motherboard as you have. Maybe you could upgrade? I just upgraded another of my PC's to quad and 4 GB ram to run vista later on, and for a new processor and 2 x 2 GB RAM I payed less that $400. Dono about retailprices on hardware at your place, but it here it's cheap atm.

/Ulf

Sebaz wrote on 5/24/2008, 9:18 AM

Yes, I had a Canon HV20 for a little while and the HDV files from it play perfect from the timeline, except when Vegas is redrawing the timeline thumbnails, which slows the fps quite a bit, but other than that they play fine.

Note that I tried disabling thumbnail and waveform preview in AVCHD editing but still playback is slow.

Sebaz wrote on 5/25/2008, 2:27 PM

I noticed that a way to increase playback fps is to set the project dimensions to 800x450 while using Preview (Full). The only drawback is that you have to remember to set the dimensions back to 1920x1080 before the final render, but this allows to work a little faster, although it's still not real time playback. It might also help that I keep the preview window at 800x450 too. I tried lower dimensions but there doesn't seem to be any gains.

Wolfgang S. wrote on 5/26/2008, 1:53 AM

What you can do, is to set the preview quality to half - that improves preview capabilties of Vegas. Avoid the external preview in that case.

Your 2-core processor is a little bit out of date, for 1920 AVCHD. Even with an overclocked 4-core Q6600 - from 2.4 Ghz zu 3.3 Ghz - you receive preview capabilities for two 1920 AVCHD streams only (measured on the internal preview with full preview). So, the best strategie would be to upgrade to a fast quadcore.

Sebaz wrote on 5/26/2008, 6:43 AM

I tried setting the preview quality to half, and it's useless. In fact, I think it makes it worse, I noticed that the fps goes down when setting to half on any quality. Not to mention that it looks horrible. For now I'll stay with setting the project dimensions to 800x450 and then switching back to 1920x1080 before the final render. One of the advantages of this is that it gives me a RAM preview of 20 seconds, while if I leave the project at 1920, in full it gives me 4 and in half it gives me 13.

I see what you mean about my processor, and I know eventually I will get a quad core, but if I'm going to spend the money, I'd rather wait until the extreme ones come down in price.

However, I don't think this is only a processor related issue. I mean, even from Vegas itself, when I select the source file in the explorer or project media tabs and play it from there, it plays at full quality and fps. Then why does it not play in the same way from the timeline? I would understand it if I had added different filters, motion, etc, but why doesn't it play smoothly when it's clean of effects, when it does play smoothly from the explorer tab? My point is that if my processor wasn't powerful enough to decode AVCHD then the clips would still play at 10 fps from the explorer tab, or when I play them in Pixela ImageMixer, VLC, etc.

Wolfgang S. wrote on 5/26/2008, 7:50 AM

There seems to be always the possibility, that the preview capabilites are reduced when setting the preview to half. Some user reports, that it improves the preview - but some find, that it becomes worser, even in the fps measured in preview. However, on the internal view, a lot of users report that half preview seems to show higher preview performance. That is also true for my overclocked Q6600, where I am able to run two 1920 AVCHD streams. That is not possible on the external preview, using the Intenity pro. So it seems to depend on your specific PC.

Preview quality in terms of picture resolution is better, if the preview is in full-HD - sure. Here I really like the Intensity Pro working with a full-HDTV - it is the perfect preview. With my Intensity Pro, preview is reduced if I switch away from 1920x1080, since then it seems to be necessary to scale the material down (what requires performance capacity).

You also have to disable internal preview if you work with an external preview - seconday display or the Intensity. That improves performance too.

Beside that, the AVCHD material takes a lot of processor performance in Vegas. Higher Ghz show significant higher preview performance, since even on quadcore processors the processor is not utilized to 100%. From that side, I still assume that there is significant for improvement in preview fps.

In addition, we see now the first NLEs that show a significant improved preview performance in fps. Pinnacle Studio 11+ has been slightly better then Veags 8b is, but now we see also the - maybe buggy - Cyberlink Powerdirector, what has a much better preview capability for AVCHD, compared with Vegas. I hope that Vegas will be improved further with Vegas 8c.

UlfLaursen wrote on 5/26/2008, 11:29 AM

So, the best strategie would be to upgrade to a fast quadcore.

I would say that too. You will get faster rendering as well.

/Ulf

Former user wrote on 5/26/2008, 2:52 PM

Where HDV works by compressing each frame of video, AVCHD compresses by evaluating previous and following frames (for each frame). Compressing optimally for EACH frame relative to those around it means a LOT of information. I have a 2.6GHz quad core, and it's still pretty slow editing and rendering. Eventually hardware will catch up to AVCHD, but in the meantime, upgrade and go from there.

I actually choose an HDV camera for the next couple years of work until systems catch up. Just a personal choice for workflow. Fortunately, I haven't experienced the HDV hell that others are having with Vegas (so far at least).

Sebaz wrote on 5/26/2008, 7:52 PM

I'm not an expert, just an enthusiast, but I don't think you're quite right on the way HDV works. DV had only I frames, but HDV uses a lot of B frames in addition. That's how it gets to achieve good HD quality with the same bitrate DV does.

bigrock wrote on 5/27/2008, 10:52 AM

If you really want to see slow try editing Motion Jpeg Security Video on Vegas in the Trimmer, it is slow Vegas freezes for 10 minutes at a time. The Sony Motion Jpeg codec is none too swift. Finally gave up and converted all the video to DV.

24Peter wrote on 5/28/2008, 9:28 PM

Sebaz - other than your preview issues, how do you find editing AVCHD from your HF100 in Vegas? I currently have an HV20 and am considering going tapeless.

busterkeaton wrote on 5/29/2008, 12:00 PM

Where HDV works by compressing each frame of video, AVCHD compresses by evaluating previous and following frames (for each frame).

I believe this is incorrect. Both HDV and AVCHD evaluate previous and surrounding frames. Google HDV and GOP for more technical info. The reason AVCHD is harder to work with is that it uses mpeg 4 compression where HDV uses mpeg 2 compression. So AVCHD is much more compressed and that requires much more math to be done by your computer to uncompress it.