Blackmagic Forum

I've got a new GoPro 9. I'm trying various gauge rendering packages that use the GPS/GPX data from the video to show speed, track, grade, etc.

The recent GoPro put the GPS/GPX data in the MP4 as local metadata.

I'd like to do a basic Color pass on the video before processing it with RaceRender or other tool,
so that I can get the color, exposure, sharpening, etc. close to correct before adding in the gauges. If I let the overlay tool put in the gauges first, then when I color correct, it adjusts the gauges too and they look inconsistent.

What I've love is to put a pass thru Resolve, export it, and then add the gauges. I would then render that, and do a second pass with Resolve to make it prefect.

This would only be possible if Resolve would export the GoPro metadata untouched and in same frame as it was in the original video clip.

Is this possible?

Try it. Then you'll know.

No, but you can always use FFMPEG to copy it from input to output file.

peterjackson wrote:No, but you can always use FFMPEG to copy it from input to output file.

I'm not following you here. If I process the original video (Version1) thru RaceRender or other tool, I get a merged modified file (Version2) with the original video plus the overlay. But doing it in this order means that the colors of the gauges are fixed.

I have used FFMPEG to merge video files, and do other sorts of utility functions.

If I use Resolve on the original and color grade it, and lose the metadata, there is no metadata for the overlay program.

Jim Simon wrote:Try it. Then you'll know.

Well I tried it. In my testing, Resolve stripped out the foreign meta data.

This means that the default Resolve settings remove it. My testing does not mean that there isn't some option or switch that will make it keep it. But unless I can find it, I have to assume that it will always throw away the GPS metadata

I'm not aware of any user options for that, so Peter's work around might be best.

You could try Exiftool to read and write metadata.

Thanks, but of course, using ffmpeg to separate out the metadata is going to make the challenge of keeping the GPS data and video in sync worse.

What I specifically want to do is keep them together, but be able to do color grading (along with exposure, sharpening, etc.) that do not impact the length of the clip. Then export the improved video and meta data to feed into RaceRender, or other software in the chain that generates the overlays for speed, track location, etc.

So the work chain is:
camera -> color grading -> gauge overlay -> normal video editing (titles, cut, zoom, crop, etc.) with any fancy stuff -> render -> Handbrake for H.265

I'd love to skip Handbrake as well, but I can't see how to render H.265.