Export as .mp4 container?

…Is HEVC a better option to get better results in quality and smaller file size?…Can HEVC be wrapped into .mp4?…What’s the best data rate to choose from the compression setting if HEVC chosen for 1080p/720p delivery?…

Delivering a file to a client (the OP question) vs uploading are two different things. The ability of various playback systems to handle HEVC varies. I’d be a little hesitant about blindly delivering an HEVC file or expecting it to work on some unknown venue playback system.

For upload that is different – Vimeo and Youtube handle .m4v HEVC files from FCPX OK.

The issue then is bit rate and bit depth vs playback quality. If the source material is 10-bit or higher (increasingly common), there can be definite quality advantages to 10-bit HEVC vs 8-bit H264, even if HEVC is 1/2 the bit rate. 10 bit material shot with a flat color profile and containing gradient scenes will often show banding after color correcting and exporting to 8-bit H264.

To my knowledge 10-bit H264 is not that standardized and I would not deliver a 10-bit H264 file to a customer, even if FCPX could encode that (which it cannot; Compressor can).

10-bit HEVC is more standardized, but the issue is can the client system handle that from a performance standpoint. You don’t want a client to play it OK on an iPad, then find an old Windows machine at a venue cannot handle that at all or drops frames. But delivering any kind of HEVC to a client is risky. Eventually it will be more widely supported.

Another issue is no current Mac computer (including the new Mac Pro) has enabled hardware acceleration for 10-bit HEVC encoding from FCPX or Compressor. They are extremely slow — roughly 30x slower than exporting to 8-bit HEVC or H264.

If you need 10-bit output for upload, the dilemma is ProRes is often too big and 10-bit H264 is not standardized. This leaves 10-bit HEVC which is currently super slow to export on FCPX/Compressor on any Mac hardware. A workaround is export to ProRes 422 which is really fast if the timeline is rendered, then use Handbrake to transcode to 10-bit HEVC.

Handbrake apparently uses hardware acceleration (at least on my iMac Pro and 2017 iMac 27). Despite using two separate steps, it is vastly faster than exporting directly to 10-bit HEVC from FCPX. Quality seems good. Procedure:

– Export from FCPX as ProRes (typically very fast if timeline is pre-rendered)

– Import to Handbrake, use the video encoder labeled “H.265 10-bit (x265)”.

– If using 24 fps, there isn’t a 24 fps pre-set so pick Vimeo/Youtube 1080p60

– In Video tab, modify it for 23.976, encoder preset slider: VeryFast, constant quality slider RF10. Do your own QC tests and adjust to taste.