How to reduce sun glare, brightness, loss of detail through whitened parts of footage?

If you check the footage properties in the Composition Panel then mouse over the brightest parts of the image and check the Info Panel for color values you can tell if there is any information to recover. 8 bit (normal video) footage has a maximum value for all channels of 255. If you see 255 then there is no additional detail to recover. 

If you have higher bit rate footage and your info pannel's color settings match the footage then the same rule applies. If there are areas in the image that are at the top of the color range there is little or no information to recover.

In the screenshot that Charles posted there is still information left to recover. The request to create an Auto-Brightness plug-in, that already exists in several of the color correction plug-ins including Lumetry. Even the Curves effect has an Auto button. Lumetri has Auto. Even Euqalize will do an initial fix on footage in AE.

The tutorial Charles posted is showing a kind of funky workflow in Premiere Pro that a professional colorist probably would not use, and because the frames are identical and it is the presenter is in the frame it is hard for me to believe that the "overexposed" footage on the right is just a copy of the footage with a basic levels or curves applied to the footage that is being overridden with Lumetri. N

Charles, AE has excellent tools for color correcting footage. The Auto function in Curves or Lumteti will get you to a decent starting point in a single click, but really color grading an image takes a lot more than a couple of clicks. There are a lot better tutorials on using Lumetri than the one you posted. Even when you go to $$$$$/hour color grading suite with millions of dollars of equipment the initial AUTO selections only get you to a starting point, and even the most expensive suite in the world with the best software available cannot recover information that is not there. The less headroom you have in an image the more likely it is that you are going to create banding in recovered highlights or shadows. 

I took a screenshot of the presenters "overexposed" right side of the frame, added the 8bi screenshot to a new AE comp, duplicated the layer, and set the two layers beside one another. I added Levels first with no adjustments so I could get a good look at the pixels I have to work with, then applied the Equalize effect to the frame, then put a copy of Levels below to see how many holes I ended up with the initial fully automatic color correction. This is a 32-bit comp, but as you can clearly see, Equalize gave me a pretty good fix, and the Levels display shows a full range of color, but all of the holes in the histogram show the potential color values that have no information. The only way to fill in those color values is to have a higher bit depth image to start with.

I almost matched the presenter's final color grade of the overexposed (??) footage by simply applying Equalize and then adding a couple points to Curves. Looks pretty good for about 20 seconds of work on an 8-bit image.

Here's another approach, another 10-second fix for the footage to get the Over Exposed footage looking properly exposed. Just two steps. Add Levels and adjust the input black level up until it just approaches the first dark pixels on the left. Second, add Curves and crush the blacks a bit and be careful with the whites. It looks pretty good with almost no work.

Frankly, I would give that tutorial a C- because it was just a quick rundown of some of the Lumetri settings and a very rudimentary explanation of how to read and use scopes and misses the point of matching the color grade in different shots, which is the real job of color grading.

I hope this helps you understand the process a little more. One more thing, I'm not sure what benefit you expect to receive from the MediaInfo app? AE reads all of the color information, metadata, and any other info needed from the image or video without any manipulation by the user.

Short version: What's not there, is not there. As far as computer math is concerned, there is no such thing as a "whiter than white" pixel and there is no underlying data to recover once the dynamic range/ gamut has been maxed out. Of course that doesn't preclude that your footage could not be enhanced in some way like e.g. removing a slight white haze from overexposed footage, but generally you should not expect miracles, even more so since your resolution is extremely low by todays standards and every operation on your footage will degrade it further and only bring out the existing compression artifacts even more. In any case, at least a screenshot would be required to advise on specific procedures. Aside from that there is no "match source" render settings. It's just not how the programs work and AE in particular has no pass-through, anyway, meaning every output gets re-encoded from scratch based on the expanded RGBA buffers, anyway. Conversely, since your footage is not based on a standard production format, even Premiere would not be able to do such a thing, so this is pretty much a moot point.

Mylenium