Premiere export video -audio bitrate problem

[ju22259367ig3g]

As per apple app store launching requirement, video audio bitrate is requested to be 256 kbps,

so I need the file having the exact specification.

However, Premiere export the file with the audio bitrate a bit lower than the one in setting, i.e.setting 256 kbps and outcomes 247 kbps.

I have tried so many settings within the requirement but neither one gives me a correct exported file.

The source file is 3xx kbps which exceed the rate I need. So I'm really confused and hope to know the solution....

[neil wilkes]

Are you using a VBR or a CBR encoding please?

Also how are you ascertaining the audio bitrate is 247kbps instead of 256kbps?

Is the source file lossy or lossless?

Are you on a Mac or a PC?

The more information you can give the better chance we have of actually solving your problems.

[ju22259367ig3g]

Thanks for the detail,

I'm not sure about the encoding, where can I do the setting & which one is better?

For the audio bitrate I check it in file information by Mac "Music" App,

and the source file got higher bitrate than I need so I think it should be ok for the export?

[Michael Grenadier]

Honestly, I'd try submitting it with the approximate requested bit rate...  bwdik.

[ju22259367ig3g]

Just doubt if app store launch my video successfully with a approx. bitrate,

it's a task for work & another department help with the launching & judge me with the specification

...so let's see

[neil wilkes]

Just doubt if app store launch my video successfully with a approx. bitrate,

it's a task for work & another department help with the launching & judge me with the specification

...so let's see

By @ju22259367ig3g

Your problem here is that anything using a variable bitrate can only ever provide an approximate bitrate to the app store. You need fixed bitrates with audio - this is yet another reason why lossy audio is bad for your general wellbeing & state of mind.

What you need to do is extract the audio from these Hero devices and turn it into something nice & sensible - PCM. This will give a fixed bitrate, and you will find a lot of audio problems, glitches & upsets will melt away like the spring snow on a sunny morning. You will also have less stress in your life.

The best place to start is with the devices themselves - tell them to use PCM WAVE files, not MP3, AAC-LC or any other lossy garbage. Honestly.

[Michael Grenadier]

I don't think recording as a .wav file is gonna make a perceptable difference but testing is the way to find out, but converting to wav or aiff with a standard sampling rate of 48k before editing is always a good idea.   And not sure about hitting a precise bitrate on your output, but for posting on youtube/vimeo/instagram/facebook the export presets in premiere/ame are all aac and I've never had any issues.. In fact, I don't think you can actually output an h264 with uncompressed audio...  I recently cut a music video and the audio engineer insisted that I output the final piece for posting on youtube as uncompressed and I had to output as prores to be able to have uncompressed audio.  Don't think I could change the audio to uncompressed with an h264 video compression (unless I'm having a senior moment and misremembering.

[Michael Grenadier]

yup, just looked.  you cannot encode an h264 file with uncompressed audio at least in AME...   The OP didn't say what format he was encoding to and even if he's posting as a quicktime file, almost all websites will eventually enocde as h264.   Not sure about the apple app store.  Maybe the OP can post the requirements...

[neil wilkes]

No, but what you can do is output with a CBR AAC-LC file (say 256kbps) from a lossless master.

This is why whenever any edits are being rendered for the first time you should use either a ProRes MOV or a DnxHD MXF with PCM sound as your master. Not only can this then have any necessary post production work carried out on it before creating streaming platform masters such as Apple TV, Amazon Prime, Discovery Channel or YouTube or whatever is required.

We never, ever render a streamable file from the edit project. What we will do is create the edit project from all the different clips, and get this done first. That will be exported as DnxHD MXF (I do not like to use ProRes as there can be gamma issues if you go cross-platform with quicktime ProRes, which is why Apple have deprecated it, but sometimes a client will insist on a ProRes reference for signing off purposes) for approval, and once that is done (we upload the full original to a private Vimeo account, each file password protected, & let the client view from there) we will create a new project for making all the deliverables.

I guarantee to you that nothing will get bounced by streaming platforms if you use this method.