so4compoundplug.dll issues

jimingo-1 wrote on 1/12/2021, 6:14 PM

I'm using Vegas 18 and I'm having a lot of issues related to the so4compoundplug.dll but there are multiple options to change the settings for the so4 reader so I'm not sure which ones to choose. The footage that is giving me the issues are DJI Osmo AVC (3840x2160 at 23.976fps) and Canon 5D4 AVC (1920x1080 at 60fps). In internal settings, there is "hardware decoder for so4 compound dll". That is set to 1. There is also a "blacklist mode for so4 compound reader". That is set to 2. There's also an audio option for so4 but I doubt that matters. Also, in the File I/O settings, there is an option to "enable legacy AVC decoding".

I'm not sure which ones to change. I know changing the "hardware decoder for so4 compound dll" to a O definitely improves my issues, but I'm not sure it it should be used in conjunction with any other changes and not sure if I should enable legacy AVC decoding. And, if I enble legacy AVC encoding, should I set the internal settings to their default values or to other values?

I should also mention that I'm using a Nvidia GTX 1650 super.


RogerS wrote on 1/12/2021, 9:25 PM

Can you describe the issues you are having?

Maybe set them all to defaults and start again. I wouldn't play with the internal preferences. Install the NVIDIA Studio drivers for the GTX 1650.

The DJI Osmo and Canon are not the same type of file so don't require the same treatment.

The Canon ones should work with all settings at default. (it's Mjpeg? Maybe post the mediainfo for that file here)

I believe the DJI ones are blacklisted by so4compound (which means they automatically get the legacy decoding treatment)? They may benefit from transcoding to an editing-friendly format if you are willing to do that.

jimingo-1 wrote on 1/12/2021, 10:21 PM

Thanks Roger. Sure, the issues I'm having are terrible timeline playback (like 2 frames per second) and Vegas won't open projects that have multiple DJI files in them. It just hangs forever. If I disable the GPU in the settings, Vegas works and no longer hangs, but then the GPU is disabled so that's not a great option.

I do realize that the Canon and DJI are different file types but they both use the so4compounddll and I'm certain that's the culprit. The Canon only uses Motion JPEG for 4K files and I transcode those files anyway. The files I'm dealing with from the Canon are only HD. They're .mov files but like the DJI files, they are listed as AVC .mov in Vegas.

Also, I do have the latest Studio Driver installed.

I did some more tests and it seems like two scenarios seem to fix my issues. 1) If I change the "hardware decoder for so4 compound dll" to a O in internal settings. Or 2) changing all the internal settings back to default while enabling the legacy AVC decoder in Internal settings.

But, I'm wondering if I should be using these in conjunction or are there other settings that should also be changed since there are multiple options of dealing with the so4compound dll. Basically I'm just trying to figure out how to get optimal playback.

RogerS wrote on 1/12/2021, 11:44 PM

This is good to clarify.

so4compound isn't something bad to be disabled as a first step. It provides modern decoding for a wide variety of files and enables both GPU hardware to be leveraged as well as support for 10-bit formats. Disable it and you disable these features. You can disable it by checking enabling legacy AVC decoding, which is a front-end for the internal preferences you are also changing.

In your case I think you need to isolate the problem. Try the Canon AVC files alone. They should work fine with so4compound and all settings on default. I don't have Mark IV files but used older Canon HD AVC .movs without issue. Feel free to upload a sample if there's something unusual about it. If even this doesn't work there's something else amiss with the settings in Vegas.

The most likely problem is the DJI files. Can you provide MediaInfo for exactly what these are?

Others who use DJI may have ideas for best settings in the device and Vegas.

Of course if you're already used to transcoding, you could try transcoding them to a better format for editing until Vegas support improves.

JN- wrote on 1/13/2021, 4:35 AM

@jimingo-1 There is an issue with mjpeg file from Canon 4k files, once you try to load ~ 40 plus, not sure if it applies to FHD. The latest update, HOS version, just released, from @wwaag handles mjpeg in an AVI container. I’m not sure if he means by that that the mjpeg files are converted into an AVI container, or that if they are already in one, and he now supports that.


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Harold-Linke wrote on 1/13/2021, 5:52 AM

@jimingo-1 I am using DJI Pocket 2 AVC files (3840x2160 at 25p/s and 50p/s) in VEGAS 18 without any issue. I assume that they have a similar file format. I have an NVIDIA 1060 6Gbyte card. This card is using a Pascal chip while your card has a Turing chip. So there might be an issue with your grafic card support in so4compoundplug.dll

3POINT wrote on 1/13/2021, 1:42 PM

@jimingo-1 I can import and edit DJI Osmo Pocket 2160p24 ((3840x2160 at 23.976fps) with Vpro18 and VMS17 without issues.

j-v wrote on 1/13/2021, 2:11 PM

Also nothing wrong with that on my laptop from signature

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