Very slow rendering with VS10+

[koocha]

Hi

Why is my rendering so slow with VS10+?

I have a 26min .avi (720x576, 578kbps, DivX) and I'm creating a DVD with no menu.

So far I'm 12% total done, 61% of the title done and 1hour 49mins into it! It's only 26 mins long!

I have an Dual Opteron 165 running at 2.57Ghz, 1.5Mb RAM, SATAII HDD...

Any ideas? I could really do with this being faster

[Terry Stetler]

I think we get this one about 5x a week, minimum

DivX, XviD, WMV, MPEG etc, etc, are all temporally compressed formats, meaning for every second there are maybe 2-3 real bitmaps separated by numerous synthetic frames calculated from the previous and next bitmap (I-Frame). The synthetic frames are called B or P frames. The whole collection is a GOP, or group of pictures.

These formats are for distribution, not editing, and one of the prices of attempting to recompress them to another format (in essance: an edit) the transcoder has to make real data out of all those synthetic frames.

As you have discovered this is VERY CPU intensive, and if the source format differs in how the GOP is arranged vs. the destination format things get worse, not better.

I typically convert them to an uncompressed format (HuffYUV or Quicktime/Component) or MJPeg before doing anything with them. In my experience this gives better results and is acutually a tiny bit faster as the transcoder doesn't have to do the IBP frame re-alignment thing.

[koocha]

Thanks for the reply. Why doesn't NeroVision Express have a problem with them then?

[Terry Stetler]

Because Nero Vision is one of the fastest encoders out there right now, if not the fastest. I'm highly suspicious that it, like the ATI AVIVO encoder, may use the GPU's pixel shaders to decode the video...which is about 3-6 times faster than CPU only encoders can do it.

[Ken Berry]

koocha -- can you tell us whether you are trying to produce a 'standard' DVD i.e. one which uses DVD-compliant mpeg-2 format, or one of the newer DVDs which uses mpeg-4 formats such as DivX? If the latter, then there are other programs out there more suited to the task. You have mentioned Nero, but I use one called DivX2DVD...

[koocha]

It's just a standard DVD afaik.

Coming up to 3 hours for a 26 min file...

This rendering time is seriously putting me off using VS10+

[Ken Berry]

It's not really the fault of VS. As far as I can guess, you are not following the recommended procedure for producing a standard DVD, which is contained in the top sticky post. Essentially, though, you are starting off with video in a format which is difficult to edit (mpeg-4/DivX which happens to have the carrier format of .avi). Anyway, our recommended procedure is, after editing, to convert the file to a DVD-compliant mpeg-2. To do this, you go to Share > Create Video File > DVD. Instead, I think you jumped this step and went directly to Share > Create Disc > DVD. The computer is thus having to work overtime to convert the file AND then multiplex and burn it on the fly. This will inevitably be a lengthy process, made moreso by the format you started off with. And it is also likely to cause less powerful computers to give up the ghost...

Now, I have actually used VS10+ to convert mpeg-4 files to mpeg-2, and the quality has been excellent. I have also done the reverse, and created DivX files from DV and mpeg-2 originals. But in this process, you have to be extremely careful as to how you configure the DivX codec. However, if you get it right, the results can also be excellent.

But while this is possible, and Ulead in fact advertises (correctly in my view, though not of others) that VS10+ can handle mpeg-4, and provides its own codecs for this, I am not sure that it has been tweaked specifically to do it as well as a program like Nero or other programs designed especially around mpeg-4/DivX, like DivX2DVD...

Unfortunately, from your apparent point of view of time being of the essence, the recommended procedure I outlined above will still take time. The conversion still has to take place, and this will take time whether it is part of a single process, such as I imagine you are undertaking, or as a single step in the procedure I follow. It's just that our recommended procedure is less likely to produce a failure...

But if you think Nero is better, then by all means use that. I for instance do so regularly, and I am quite impressed these days by Nero 7 Ultra's choice and sophistication in menus, for instance...

[PABrowns]

Check you CPU usage (with Task Manager if nothing else). I found that I was only using about 50% at first. Then I added a second hard drive. Using one drive for system and one drive for working sped up my system considerable. Now my CPU is the rate limiter and running about 98-100% on both virtual cores in hyperthreading mode. Next step Conroe?

I also added another couple gigs of memory. I now have 3 GB of 533 MHz. Honestly, I rarely use more than 1GB. With a dual Opteron system, however, you may benefit from adding more memory per processor if you aren't running NUMA.

But even with a SATA drive, I think the best way to improve speed is using 2 drives. Otherwise the single drive creates a very narrow bottleneck.

[lespurgeon]

Single 165 or dual 265s?

Either way, a 185 could help, or if you are on a 939 pin platform, an FX60.

In my experience, videostudio dos not do a good job of using dual cores for rendering, you probably have one core at 100% and the other 1 (or 3) cores at 0%. I have not found a fix (X2 4400 running at 4800 speed here).

[sjj1805]

Just as Ken said, I convert them beforehand with DivXtoDVD. - actually its been renamed to ConvertXtoDVD
It's much quicker and purpose built for the job.