Faster Ways to Export H.264 and HEVC Video from Final Cut Pro

In January, I looked at how rendering affects export speed in Final Cut Pro. Specifically, I wondered whether Final Cut Pro exported faster if you rendered the timeline before exporting.

The short answers are:

• When a project is unrendered, it takes the same amount of time to export into ANY version of ProRes
• When a project is fully rendered using the same codec as the export format, export times are significantly faster – generally 4 – 5 times faster – than an unrendered project.
• When a project is fully rendered but exported into a different ProRes codec, export times are the same as an unrendered project.

This week, Flick sent me an email wanting to render using HEVC (or H.264), since all his projects deliver in that format to the web. He was looking for a way to save time.

However, FCP does not support rendering in either HEVC or H.264, as the project render files options shown in the screen shot above illustrate.

My guess is that the compression architecture using in both H.2645 and HEVC (Long-GOP) significantly degrades performance, especially on older systems. So, you can only render into variations of ProRes or uncompressed 10-bit 4:2:2 media.

This created two new questions for me:

1. Are export speeds different if you first render a project using ProRes 4444 or ProRes 422?
2. Is it faster to compress a file using FCP or Apple Compressor?

Since both FCP and Compressor use the same compression engine, image quality should be the same, but, perhaps not the speed. This weekend, I decided to find out.

EXECUTIVE SUMMARY

Here’s what I learned:

• Exporting the same format as the project render files is five times faster than exporting into any other format.
• Projects rendered using ProRes 4444 export marginally faster than those rendered using ProRes 422. However, the speed improvement is not worth the larger render file size in most cases.
• If you only need to create one compressed version of a project, render in ProRes 422, then compress in Final Cut Pro using the Share menu.
• If you need multiple versions of the same project, it is easier to export a single ProRes 422 master file, then use Compressor to create multiple versions of this source file. However, it is faster to export each version separately using Final Cut.

This last finding was the one that surprised me.

WHAT I DID

I created a ten-minute 4K project composed of 33 different ProRes 422 4K clips; with effects as shown in the screen shot above.

The primary storyline contained eleven 4K clips, using straight cuts and no effects.

Compound clip 1 contained eleven 4K clips with the following effects:

• 30° rotation (CPU-intensive)
• Gaussian blur (GPU-intensive)
• Drop shadow (GPU-intensive)
• Repositioned in the frame (CPU-intensive)

Compound clip 2 contained eleven 4K clips with the following effects:

• 40° rotation (CPU-intensive)
• Simple border (GPU-intensive)
• 50% desaturation (GPU-intensive)
• Repositioned in the frame (CPU-intensive)

I then fully rendered this project using first ProRes 422, then ProRes 4444. Finally, I timed how long it took to export this project in six different codecs:

• ProRes 4444
• ProRes 422
• H.264, using the Share > Export File option
• H.264, using the Share > HEVC option (which also included H.264)
• HEVC 8-bit (4:2:0 color)
• HEVC 10-bit (4:2:2 color)

NOTE: There are two ways to export H.264 media: File > Share > Export File and File > Share > HEVC – High Efficiency Video…. HEVC can only be exported using the HEVC menu option. The HEVC option is slightly faster for both H.264 and HEVC. (The ADD H.264 option only exists if you have installed Audio Design Desk software on your system.)

I exported H.264 and HEVC using single-pass compression settings, where choosing that option was available. This engaged hardware-acceleration for faster encoding. ProRes rendering and exporting always uses hardware-acceleration.

WHAT I LEARNED

TABLE NOTES: Speed Difference compares the speed of exporting a different codec to the render format. While interesting, the more helpful results are indicated by total compression time. Note how similar compression speeds were for H.264 and HEVC, regardless of render file format or video bit-depth.

This table shows that:

• Exporting a file that matches the render format is always the fastest.
• Regardless of whether render files were created using ProRes 422 or ProRes 4444, export times were within a few seconds of each other, if not identical.
• Exporting a master file as ProRes 422, then compressing it into different codecs individually using Apple Compressor is marginally faster than creating a single batch where all formats are created at the same time.

NOTE: Compressor treats batches differently than Adobe Media Encoder, which processes all formats of the same file at once. Compressor processes them sequentially. Media Encoder will be faster at compressing batches of the same file.

SUMMARY

I was not expecting export speeds to be this consistent between codecs. I was also very surprised to see that creating a batch of files in Compressor – though more convenient – is not faster than compressing each file individually.

EXTRA CREDIT

When picking the best render format, keep these thoughts in mind:

• For material shot using a camera in the Rec. 709 color space, there’s no quality value in rendering or exporting using ProRes 4444, especially given the much larger files that ProRes 4444 creates.
• For material shot using Log or RAW formats, or media created on the computer (i.e. After Effects or Motion), color accuracy is better when rendering and exporting ProRes 4444.

---

Bookmark the permalink.