Premiere ignores my bitrate settings

[Fifan_Ebusto0374]

I always rendered my videos in Full HD, H.264 using VBR 1 (pass) at around  20-25 Mb and everything seemed to be okay, but at some point Premiere just started to ignore my export settings. Even when I set the max 50 Mb for Full HD, the outcome wouldn't get higher than 5-7 Mb, no mater what codec I chose. The size of my videos also didn't match the estimated size that Premiere suggested because of that. 

I also noticed that it never happened when I'd worked with simple and small projects with little to no effects/transitions/etc.; Premiere "ignored" the bitrate setting of much bigger, heavier and complex projects. 

I tried a lot of stuff and finally fixed it - I had to turn off the Hardware acceleration and use CBR instead of VBR (switching to CBR while still using HA didn't help, as well as using Software Acceleration with VBR; it only worked when I did both things at once). Now Premiere renders my videos with the bitrate I need, though it's much slower.

And though everything works more or less fine now, still. Can someone explain me why that possibly could happen?

[christianot40873293 · Accepted solution]

Based on your description, this issue likely stems from the interaction between hardware acceleration and memory management during video encoding.

Here's what's probably happening:

When using Hardware Acceleration with VBR, The GPU handles both video processing and encoding.
Complex projects with many effects require more GPU memory and when memory becomes constrained, the encoder may automatically reduce bitrate to maintain stability, maybe this explains why simple projects worked fine while complex ones had issues

Why switching to Software encoding with CBR fixed it?
Moving to CPU encoding removes GPU memory constraints, CBR provides more predictable memory usage patterns.
The CPU can access the full system memory, preventing bottlenecks
Though slower, it maintains the specified bitrate consistently

The reason both changes were needed is that Hardware acceleration alone would still hit memory limits even with CBR
Software VBR could still cause memory spikes that affect encoding
The combination ensures stable memory usage and consistent bitrate

The estimated size discrepancy occurred because Premiere's size estimation assumes ideal encoding conditions, not accounting for potential hardware limitations during actual export.

Possible solutions I would try->
1. Reduce project complexity by pre-rendering complex sequences
2. Increase your GPU's memory allocation for Premiere if possible
3. Split very complex projects into smaller segments for export

[Fifan_Ebusto0374]

That's a great explanation! I'm kind of okay with a bit slower render process, so I guess I won't change the setting for now, but it seems like things you described are indeed the root of my problem. I hope this thread will help somebody facing the same problem out there as well

[Kevin-Monahan]

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Thanks,
Kevin