x264 - filesize output calculator for 2-pass and CRF ?

hello guys,
does anyone know if there is a filesize output calculator which can tell me in advance how big my output file will be ?
In HCencoder it was possible. You just had to import your .avs script and there was a field which was called "file length in kbytes" which told you exactly how big your file will be in the end.

Is there something similar for avs script based x264 encodes ? It would be even more awesome if it had a field where you could insert how many audio tracks you use and how big each audio track is and automatically telling you if your x264 video file is too big.

Thanks in advance for you suggestions
regards

I use this bitrate calculator to obtain the average bitrate to pass to x264. That's all you have to do: HCenc's GUI simply had a bitrate calculator built in.

I use this bitrate calculator to obtain the average bitrate to pass to x264.  That's all you have to do: HCenc's GUI simply had a bitrate calculator built in.

thanks a lot I will try that out. Regarding rate control there is only 2-pass but I guess CRF will probably not be possible since it varies from source to source.

Yes. Avoid CRF encoding if you need to hit a certain file-size.

[spoRv]

Also allow some headroom for the m2ts files if you want to build a BD compliant disc - 6% should do, but I always leave 7%, just in case...

Yeah, there's an option in the bitrate calculator for "other assets". I use that to factor in the overhead.

Also allow some headroom for the m2ts files if you want to build a BD compliant disc - 6% should do, but I always leave 7%, just in case...

6-7 % is quite a lot. I'm going for a BD compliant disc using "Blu-ray folder" as output in tsmuxer but I'm not planning to do any menus.

[spoRv]

6-7 % is quite a lot. I'm going for a BD compliant disc using "Blu-ray folder" as output in tsmuxer but I'm not planning to do any menus.

I know, and that's not even counting an eventual BD menu!

So, for example, if you have a 10GB .mkv file, you will end with .m2ts file with a size around 10.6GB.