A Few thoughts about AVC Legacy (compoundplug.dll).

Thiago_Sase wrote on 8/30/2023, 9:45 AM

Hello guys!

I'm a video editor freelancer since 2010 and using Vegas Pro since then. I Love Vegas and version 21 is huge.

During the years I had and still have different clients with different Vídeo Cameras. Here in Brazil FULL HD is very popular and most of my clients still shooting in FULL HD.

Cameras among 2010 and 2017 are very common to see here. Sony, Nikon, Canon, Panasonic, and MP4, MTS, M2T, MOV (older ones), as like as AVC and XAVC, all from those different kind of cameras, formats, codecs and containers from that period of time.

Thoses formats are not stable most of the time when using so4compoundplug.dll, and in many different systems is not smooth and are very laggy.

But, when is changed to Avc Legacy (compoundplug.dll), just like magic, everything runs smoothly, fast, and without stutters and black frames.

And i know that so4compoundplug.dll benefits the GPU and compoundplug.dll does not.

My question is:

Does Vegas Development team has plans to improve those formats, from those cameras, from that period of time to "new" So4compoundplug.dll, introduced in Vegas Pro 15 in 2017, to the future updates and versions of Vegas Pro? Or always will be better edit them with Avc Legacy (compoundplug.dll) ? @VEGASDerek

And I have to say, congratulations to the Development Team of Vegas Pro, you guys have been doing an fantastic job.

Thanks.

Comments

RogerS wrote on 8/30/2023, 10:16 AM

Are you judging this based on decoding using the RTX 3060 GPU in your signature? (I assume so but want to ask). Do you find there have been improvements since VEGAS Pro 15?

I find constant framerate AVC in MOV and MP4 containers from Sony, Canon and Panasonic cameras from that time stable and reasonably fast using the Intel QSV decoder. It wasn't so good for me with VP 15/16 but got better after that point.

Thiago_Sase wrote on 8/30/2023, 10:25 AM

@RogerS Yes, the performance is better in 19, 20 and 21. But, the laggy and stutters (sometimes weak, sometimes strong) still happen using So4compoundplug.dll, but when changed to Avc Legacy playback is faster and strong. But, yes, I noticed during the years improvements on So4compoundplug.dll since VEGAS Pro 15.

Former user wrote on 8/30/2023, 8:33 PM

@RogerS Yes, the performance is better in 19, 20 and 21. But, the laggy and stutters (sometimes weak, sometimes strong) still happen using So4compoundplug.dll

I can give you an old technical answer from an ex Vegas user:

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Back in the i386 days, there was a 386 CPU what did not support higher math functions well, so they marketed a “Math Co-Processor.” This was basically a dual processor configuration, where higher math functions would be handled on the fly by the most capable device. OpenCL and rendering in Vegas works in a similar fashion, though not exactly.

Even if you have no GPU enabled in Vegas, Vegas is still working in OpenCL for timeline acceleration. Your system CPU has virtual OpenCL processor, and Vegas uses this under normal operation. Adding the GPU to the mix allows for a dual OpenCL processor configuration. Vegas then is suppose to handle the pixel math by understanding there are 2 processors available to work the problem. If your GPU is massively faster than your CPU, you GPU will not seem to be utilized much. Conversely if your GPU is to weak, but supports the OpenCL functions, calculation timing issue will look like Vegas is not using the system effectively. Throw on top of that the fact that the GPU and GPU memory is being shared to work the displays.

Working in FP32 mode with GPU, you should see an improvement and greater utilization of GPU with effect. This is mainly due to FP32 math is more complex even for the CPU+GPU combo. The GPU does handle floating point math faster than the CPU alone. If calculations cannot be completed in time, frames are dropped, and the next frames are rendered. This calculation timing issue is why Vegas will drop frames, and do so not seemingly using all system resources.

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He seems to be blaming people's GPU's , saying they're not fast enough and that's why Vegas drops frames and lags, but as I say this is an old post, and it may have thought to be true back then. Today with very powerful GPU's we know that isn't true, and Vegas is the problem. The problem still involves GPU's but it's not the fault of the GPU's it's Vegas's poorly opimized code either creating latency or poor/low bandwidth between the CPU and GPU causing the lagging.

Thiago_Sase wrote on 8/30/2023, 9:42 PM

@Former user Interresting analysis my friend. I hope So4compoundplug.dll will be better optimized to those formats that i mentioned in the future updates and versions of Vegas. And it's Interresting that compoundplug.dll still have power and good performance in some videos files formats.

Former user wrote on 8/30/2023, 10:10 PM

And it's Interresting that compoundplug.dll still have power and good performance in some videos files formats.

If your CPU is powerful enough it's often as you described a less laggy experience than using GPU decode, which never should be the case. As you've mentioned they've had 6 years to fix these GPU decoding problems, and so far haven't, I'd like to believe they'll have the problem fixed in 7 years but as far as I"ve seen they don't even acknowledge there is a GPU decode lag problem which isn't a good sign.