VSPX3: 1-pass encode good, two-pass encode bad

[stoenjes]

Just switched from VSPX2 - bought the CD version of VSPX3 (thought it might have a printed manual). Really miss the advanced compression options. Had good looking DVD videos with VSPX2 using 2-pass encode and everything the same as below, except for setting average bit rate at 6000.

Source video: Fast moving 7-month old taped on a Sony HDR HC5 (mpeg-2, upper field first, 1440x1080, 25000 kbps)
No issues with compression artifacts or pixelation on transferred video (no dropped frames)
Preferences: Resampling quality: Best
Video file created from: 3 Share, Create Video File, Custom

2-pass output:
Lots of compression artifacts associated with motion/pixelation not associated with cuts

NTSV DVD MPEG-2, Upper field first, 720 x 480 16:9
two-pass encode, 100 quality
variable bit rate. max 8000 kbps
dolby digital audio 48000 Hz 256 kbps
size - 393,276 KB, ~ 5285 avg kbps


1-pass output:
No compression artifacts

Only change is from two-pass to one=pass encode:
DVD NTSV MPEG-2, Upper field first, 720 x 480 16:9
one-pass encode, 100 quality
variable bit rate. max 8000 kbps
dolby digital audio 48000 Hz 256 kbps
size - 406,492 KB KB, ~ 5532 avg kbps

The only comments I've seen here about 2-pass encode is that it takes longer and some issues with cuts.
Is there something in my compression settings that would cause the two-pass issues?

[sjj1805]

Nothing obvious, I take it the source material is also 16.9
Can only suggest you check that you have the most recent version of
Direct X

[Ken Berry]

I am assuming that you downloaded the HDV as such, rather than letting the down-conversion be done in the camera during capture.

I also wonder about the double whammy of using both two pass encode with the 100 setting. I personally never use 100 and always tend to leave it at the default 70. Some computers, when set to 100, have the sort of problem you have experienced -- though I acknowledge that those problems were not necessarily associated with two pass encode. However, you might want to try it with that quality setting lowered to, say, 90 or even 85 and try it again with two pass encode.

[stoenjes]

Recently updated Direct X.
The downloaded files are HD.
Tried quality at 70% with 2-pass - increased compression artifacts

Guess I will stay at 1-pass and save some time.

Stan

[spisa]

Hi.

I have the same problem with the trial version of VideoStudio X3. Rendering using the two-pass creates a terrible blocky effect. It was suggested this could be because I was using AVCHD files, but the blocky effect is there even when the original file is DVD-VR MPEG-2. When I rendered from AVCHD to AVCHD it was dreadful! The same thing happens going DVD MPEG-2 to DVD MPEG-2.

I cannot try anything more with it, though, because the 30-day trial is over.

So I'm still using X2 Pro. There is no blockiness after rendering from AVCHD or MPEG-2. But, it has it's own issue with it repeating 2 frames to the beginning of most transitions or titles. When I downloaded the service pack that was released at the end of 2008, it fixed the problem with the extra frames, but this one-pass two-pass issue was there. (I don't think it was quite as bad as it is with X3.) I tried to get help with it, but to no avail. So I had to do a complete uninstall to eradicate all traces of the service pack, and then reinstall the original X2. I had hoped a newer version would correct this problem, but the X3 trial I downloaded appears to be even worse than the X2 service pack. (I just work around the extra frames, which limits creativity.)

I have spoken to the tech guys, but apparently there are no answers. I have a laptop that I installed it on to see how it went, and it is has the exact same issue. They had me upgrade DirectX and whatever I could in my computer, but nothing changed. So I hope something may come of it by this means. And I want to know if it ever gets fixed, because if it does I'll get X3 straight away.

Thanks.

[Black Lab]

So single pass works ok? Why do you need 2 pass?

[nosnoop]

So single pass works ok? Why do you need 2 pass?

'Cos 2 pass is supposed to give you the best quality output for the given bit rate.
And I bought a faster PC so that I don't even need to think twice in going for 2 pass and the best quality in any video encoding.

[Black Lab]

But does single pass give you good results? What I am trying to get at is if single pass works ok, why the need for 2 pass. I, for one, have never seen much of a difference between the two.

[Ken Berry]

I have never tried two pass encode with high def video (which AFAIK can only apply to AVCHD anyway since HDV is CBR...) But with my AVCHD video, I just make sure I select either 'Share > Create Video File > Same as First Clip' or have a template with the necessary properties of the original video. This way, I have not been able to tell the difference between video straight out of the camera and video after editing... I also never use SmartRender on high def video of any kind.

[spisa]

I like to use 2-pass because it gives a slightly superior picture (smoother looking, although not everyone would consider this a major issue), and because the final file is smaller, meaning I may be able to fit more on a disc.

I'm also hoping that if more people who have this issue post it, a pattern may emerge that could help to identify why it is occurring with some users, and what could be needed to remedy it.

Thanks for the comments provided. I have tried various settings and used almost identical settings to stoenjes (at the beginning of this post) - except that living in Australia means I'm using PAL, not NTSC. SmartRender is turned off.

[Trevor Andrew]

Hi

You don’t say how long your video is?

The only reason to use a Variable Bit Rate is to allow us to fit more video footage to the DVD, and keep decent quality.
A standard DVD holds 4.3 Gb (approx one hour of video)

If you are encoding to 8000kbps then use the Constant Bit Rate option.

Why reduce the rate using variable when the disc is big enough to hold the full rate video

[spisa]

Thanks for your comments, Trevor Andrew.

I like to collect my home movies consecutively onto DVD's as time goes by. So a number will go onto one disc. Also, I record some meetings and other things that can require longer times. So the constant rate isn't always the best option for me.

I, perhaps, should shift to a different post due to the fact that I can’t comment further on VSX3 because the trial period is finished.

But I can comment on VS X2 Pro: I installed the service pack again to see what the results would be. The blocky bits are here and there, especially when panning, or moving fast. This effect is present regardless of whether I use 1-pass, 2-pass or the constant rate. So this is a bit different to what was happening in X3. (This is when rendering AVCHD to DVD MPEG2. I didn’t try anything else.)

I appreciate your comment because I hadn’t thought of using the constant rate.

I also tried installing the trial of X3 again. Even though I couldn’t use it, it affects the rendering of X2. It kept crashing during rendering so I didn’t see a final result of any option. Now I have to remove them both, and search my computer for anything attached to those programs. I have found that the “How to manually remove VideoStudio Pro” information in the Knowledgebase doesn’t actually remove everything. If I reinstall X2 Pro without finding and removing some other folders, it still acts as though it has the service pack installed.

Anyway, thanks again for offering your comments.