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BUG - Generate mp4 or jpg from exr sequence = ffmpeg error

If you produce an exr render via pandora or from Prism, right-clicking the preview windows and converting results in ffmpeg generating an error and the temp image being used for mp4 or jpeg. Latest build from the website. Running windows7. Tried on multiple systems, same error.

Pete

What's the error you get? And which renderer are you using?

Some older Redshift versions for Houdini produced exrs, which ffmpeg couldn't handle. But that shouldn't be a problem with current versions. Also jpgs should convert without problems with the current Prism version.

Rendered using Blender 2.9x via the Prism shelf or with Pandora, same result. Used Eevee and cycles, same result. The thumbnail is being displayed in the bottom right of the Prism dialog but the conversion fails. I can't copy the ffmpeg error as the test isn't selectable and the error line is too big to screenshot.. unless you know where this log is stored?

Looking at it, it seems it's failing on unsupported channels (listing pretty much all of them), when I'm just rendering the default blender scene of a cube and no additional channels enabled.

Its failing with the same error for jpeg and mp4 conversion.

Thanks,

Pete

Any thoughts on where the ffmpeg error log is located so I can send it? Ideally I need to sort this error out as it's pretty much now the only thing that is hampering our full integration

thanks

pete

I could replicate the problem with Blender exrs. Blender is using custom names for the color channels in the exr file, but it looks like ffmpeg requires the names "R", "G", "B". I couldn't find a quick fix for that right now. I could change the whole conversion workflow, but that would be a longer task.

How about prism checks the file extension of the source file - if it’s .blend then any resulting exr’s channels will be converted with different arguments in the ffmpeg conversion string? Or it’s disabled and prism merely converts or frame captures the buffer to at least generate a thumbnail..?

Calling ffmpeg with different arguments wouldn't be a problem. But there are no arguments, which would convert it correctly. Or at least I couldn't find them. It looks like "R", "G", "B" are hardcoded in the exr reader of ffmpeg.

Using a different tool to read the exr data like OpenImageIO would be possible, but would be more work to implement.

Sometimes when I need files converted for tasks like this, I simply use a tool. Not for task like this specifically but for some of them yes. Converting mp4 to jpg can be completed with online converter if you do not own a more professional program. To be honest, my opinion is it will save you time and you do not need to worry about losing file quality. This is my small tip.