[Ralph Baer]

Hi again, Mads. Really appreciate you taking the time to help me out here!

Not a bad idea regarding exporting to an uncompressed file. I went ahead and gave it a shot to see what my results would be but sadly it seems that H.264 is still applying what I’d consider to be an excessive amount of artifacts (bitrate and source footage considered).

Regarding H.264, that’s generally just my go-to export option due to its wide compatibility and I never quite know what file compatibility a client may or may not have, so I usually just go that route.

That said, since I’m pretty rubbish at explaining what I mean, I’m going to attempt to explain my conundrum step by step below and, from there, maybe someone can tell me exactly where I went wrong. 🙂 Apologies if I’m coming across as daft!

STEPS
Step 1 – Original Footage
I import the source footage as provided by the client. The source footage is 1080p and 17Mbps. I can tell that there are some artifacts already present in this source footage but nothing deplorable. I then trim the clip up as desired and am now ready for exporting.

Step 2 – Exporting Footage
I then export the footage using H.264. I set it to 1080p, 2 Pass, and I make sure that the bitrate exceeds the source footage by a healthy margin. In this example, I’ve set the bitrate range at 20Mbps to 25Mbps.

Step 3 – The Exported File
Premiere Pro does its thing and I’m left with a video file that has a bitrate of 20Mbps at 1080p.

Step 4 – Comparing the Export with the Source
Here’s a full resolution comparison: https://i.imgur.com/hMpLx9P.jpg When compared side by side, the exported footage has seen a significant increase in artifacts and compression. These are in addition to any artifacts that were already present in the source footage. Note the grass, the distant trees, and the clouds. All of them have undergone significant compression.

Step 5 – Increasing the Bitrate
As an experiment, I can take the same source material and export it at 150Mbps. It’s only around this bitrate that the exported footage appears to match up with the source footage. However, the resulting file size for the 3 minute clip is 3.3GBs. You can see a comparison of these images here: https://i.imgur.com/hMpLx9P.jpg

Step 6 – 1 Pass vs 2 Pass
Furthermore, I did additional testing and discovered that while 1 Pass does still add additional artifacts to the image, even when set to a bitrate that exceeds the original footage, it’s actually significantly better than 2 Pass at the same bitrate. My understanding is that this behavior should, in fact, be the reverse. Here’s a comparison of 1 Pass verses 2 Pass: https://i.imgur.com/7aE0Fir.jpg

QUESTIONS
1. With the above steps considered, does exceeding the source material’s bitrate still generate that much compression regardless?

2. Is the only way to avoid that level of compression to export the file at a bitrate that meets or exceeds around 150Mbps?

3. Is the behavior demonstrated in the above screenshots normal for Premiere Pro?

4. If the above behavior is not normal, where could I possibly begin in resolving this issue?

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[Ralph Baer]

Hey there Mads, thanks for taking the time to write up a reply! Also, apologies if I committed any forum faux pas by linking to an entirely different forum in my initial post. Figured I’d save myself a few keystrokes, I suppose. 🙂

You are indeed correct that the footage that was given to me for this project is certainly not the best to begin with and already has a handful of artifacts already. So don’t get me wrong, I completely understand that removing the artifacts from the source material itself is already a lost cause. They’re pretty much there to stay. I suppose, though, that’s why I’m taking care to try and not add any additional artifacts when exporting. Which, currently, is sadly what’s happening.

As a test, I did do an uncompressed export and layered a frame from the export over the same frame from the source and they were pixel for pixel identical. When I switch over to H264, the artifacts returned. And, to be clear, it’s additional artifacts that are the concern (not the pre-existing ones from the source footage), which is to say I’ve noticed a significant increase in artifacts in addition to the pre-existing artifacts in the source.

I’ve also been trying out different bitrates and I even pushed it up to 75Mbps on one export just to see what would happen. Interestingly enough, there was indeed less compression, though even at that bitrate it was still noticeable (which surprised me, to be honest). So just for kicks I bumped up the bitrate to 150Mbps and when exporting at that quality there finally doesn’t seem to be any additional artifacts applied. I did a frame over frame comparison of the original footage with the 150Mbps footage and they finally matched, almost pixel for pixel. That said, I can’t help but think that that’s a crazy high bitrate just to avoid compression with source footage that already has a fairly normal bitrate to begin with. The source footage is only 17Mbps and I guess I’ve always been under the impression that if I met or exceeded the source material’s bitrate that there wouldn’t be much additional artifacting or compression to really worry about. I could maybe see having to boost the bitrate up to 20 to 25 just for good measure, but 150 seems pretty bonkers.

I’m honestly not sure what to do with that information though. I can’t very well go exporting all my footage at that bitrate or I end up with 2GBs per every minute of video. Or maybe I’m misunderstanding something about the way bitrates work. Either way, even with the source material containing its own artifacts, exporting at an equal bitrate adds twice as many (if not more) artifacts. No idea why though and, I’m assuming and hoping, this isn’t normal behavior for Premiere Pro. So alas, I remain thoroughly befuddled.

Oh, and I’ll have to give the “Blu-ray” specific codec a try and report back. Good idea, Mads. Cheers!