When exporting files for cable, we typically use .mpg files which work well with the cable stations we traffic to. However, Hulu requires mp4 with a minimum bitrate of 15-30 mbps. With Quicktime no longer a viable option in Premiere Pro to get mp4 files, I have defaulted to using the built in H.264 format with our exports. However, every once in a while i'll get a message from Hulu saying that the bitrate is just below their minimum standards of 15-30 mbps. No matter what I adjust the settings to, I cannot get the output file to the correct target bitrate. Even with a target and max set at 300 mbps just as a test, it's still coming out at about 14.7. This happens with VRB 1 and 2 pass as well as CBR. Is there a correct way to get a higher bitrate when exporting as an mp4? As a comparison, our .mpg files average out to around 100 mbps.
It's conceivable that VBR could have segments below your Target. Black screens/titles for example just won't require very many bits to encode.CBR should keep the bitrate constant even when that many bits aren't needed.If you play back the export using PotPlayer and hit CTRL+F1, you'll see some stats for your video including a running bitrate.