Rendering fails eeeeeeeek!

Hi, newbie to Resolve and video editing here (but I'm very experienced with audio).

Rendering is failing and I'm kinda hoping not to lose hours of work.

I can't get it to show me the error message this time, but it tells me to make sure a file that's definitely on the drive and in the session.

Background:

- This is from OBS, and there are two pairs of video files (and two audio ones) of different sizes but with the same names - unless I'm not seeing a space or something... which seems weird, because the Finder doesn't allow two files with the same name. Anyway, I did rename them inside Resolve.

In other words, the recording got stopped in the middle and resumed.

- I've also imported .mov (iPhone) clips for the intro and ending.

- IT APPEARS TO BE FAILING IN THE SAME PLACE, which is usually a sign of a corrupted file. But I don't know.

What I'm thinking I should do.

- Delete everything from before that point and see if I can render the remaining part.

I did export a .DRP of the project before rendering, so I *think* that will let me go back to the session as it was... right?

Thoughts?

Mac Pro 5,1 upgraded to 12 x 3.46GHz, 64GB RAM, Radeon RX560, session is on an external SSD (USB 2 port, but I can't imagine it's saturating the bus), Mojave 10.14.6, Resolve 17.0.0.

TIA

OBS files are very often corrupted if the computer is running other demanding software too.
Get an external recorder if you want to edit.

Instead of trying to force Resolve into accepting a source it doesn't want (bug or not), why not just transcode the source video into a reliable format you know Resolve can handle?
There are many transcoding programs available which could convert problem videos into other container and compression formats. If the source is video only, I often even use Blender to produce frame sequences at any resolution I desire. I have yet to see any of these beta versions unable to load and use a frame sequence as a source clip going into Resolve.

"Instead of trying to force Resolve into accepting a source it doesn't want (bug or not), why not just transcode the source video into a reliable format you know Resolve can handle?"

The files were transcoded into MP4 (and FLAC for audio). Does OBS not do that reliably?

Meanwhile, you're using other terms I'll have to look up. As I said, I'm new to editing video.

But thanks.

Also, what I do involves a lot of screen capture - although this is an interview using a Zoom-like system.

So I'm stuck with OBS, never mind that it allows you to record multiple sources simultaneously - i.e. a stand-alone recorder wouldn't do the job even if it were warranted for what I'm doing.

But an M1 Mac isn't out of the question, in fact I'll probably do that when Apple comes out with a more credible model for my uses. Is Resolve's performance markedly better on them?

Nick,

What I am suggesting is a possible work-around to your problem of getting the job done, with the available tools. I have read a number of complaints in this forum about OBS screen recordings having problems in Resolve. Of course, I would like to see this understood and corrected. I have used capture video from OBS, myself, but have not seen these problems myself.

My point is that if one thing doesn't work, I am inclined to try something else. Transcoding is a term which describes a method to convert a video from one type into another. Digital video might be thought of as having two components. The "box" the video is packaged in, is called the "container". Examples of these different containers produce filenames with extensions like .mov, .avi, .mpg, etc. Within the file container is the actual method the video information is encoded. There are many further details and methods to this (using 'codecs'), which nobody wants me to explain here. The simplest for of video is the frame sequence, which is simply a numbered series of numbered images and plays in the same manner a real movie film operates, as a series of actual pictures. The image sequence is stored in a source directory and may be imported directly as a video clip in resolve.

There are many, many variables, which may get into an encoded video file, which this version of Resolve may not like. Some formats recorded from OBS might work fine with Resolve, others may not. I would experiment to see what works best. If you already have important stuff that you need to use, then I would try to transcode that work into another form Resolve is happy with.

There are free programs available, which have transcoding ability. There are also programs (like Blender) which can take most video and render it into simple, image frame sequences. One of these alternatives should help you out of this specific problem. Do a web search for them, I probably shouldn't mention any more specifics here.

Of course, we all hope Resolve's beta versions identify and fix all the needed issues leading to a stable release. For now, I suggest first experimenting to see what stable video encodings will work out of OBS. If you need to use existing video, which has problems, transcoding is an option you personally have control of.

Thanks Chris.

Meanwhile, I'm trying to export the second half of an interview with dozens of edits, and I don't know what to do.

Are you suggesting I transcode the clips that are already in there (actually there aren't a lot of clips, just long ones that are cut up)?

Yes,
My suggestion can't make your imported and edited video work, if Resolve has a problem with it. That might only be fixable by the developers. I was just suggesting that your raw footage might be be transcoded into a form that this version of Resolve could accept, edit and render properly.

I can't suggest much for a bad clip which has many edits already integrated into the project. Will any part of it render properly? Perhaps you could render out the good portions of it, and combine into a final video later. Then you could identify and deal with the part which always fails.

My original suggestion still stands. As users, we may not be capable of getting the developers to immediately solve every issue we are having with the software. We do have ability to try many possible alternatives, which might get the job done.

Thanks.

Yeah, I've rendered half of it, but it won't even render in place the corrupted part.

My next step is to try bouncing that video to disk and then giving it the same name as the original clips in the hope that Resolve will think it's the same file and apply the same edits.

Update: There's a clip that Resolve simply doesn't like.

After wasting more than enough time, I decided that discretion is the better part of valor. So I simply replaced the video that screws up with a still saying "technical difficulty, do not shake your computer device, picture will resume in a few minutes" while the audio plays.

Now I have some general questions to ask, but I'll start another thread. One of them is whether I should roll back to version 16. I don't know the program well enough to be aware of new features I had no idea were missing - I updated because the video wasn't playing properly (and now I know why).

You can roll back to 16, but it will not be able to use the 17 project file, you would need to start over.

Right, I get that, but my question is whether 17 introduces bad bugs in addition to new features.

I’m inclined to think not, since the reason I switched is that this project was freezing in 16 (and now I know it’s a file issue).

Final word on this, Part 1 (having finished this project and now contemplating my next one):

This doesn't seem to be an issue with the transcoding into MP4, because there's only one section of that clip that screws up (or possibly one small area - dunno, I was too worn down to narrow it down further).

Resolve is perfectly happy with other parts of the same 30-minute clip. So I don't see how it could be a bug.

Where are you seeing those file names? If it is within Resolve (such as on the timeline) then those are not the actual files, but links to the files. Any particular file can be used multiple times, using the same or different "pieces" of the master file. You can also have the same file (or files of the same name) located in more than one place on your computer.

Edit: The part of your message I was responding to seems to have been removed.

Thanks, but yes, I do get that! It's only *video* that's new to me - I have a long background in audio and music tech (and writing about them, and working on Macs all day long).

Anyway, I deleted that comment, because I solved the riddle.

MIDI2Marketing-20210129-211424Z.mp4
MIDI2Marketing-20210129-214424Z.mp4

^ Those are two of the files (names copied from the Finder, both files sitting in the same folder).

Can you spot what I missed? It doesn't jump out.

Yes, I see it now.