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Taming the HDV Beast
Final Cut Pro 6 and ProRes 422 to the Rescue
by Larry Jordan

High-definition video (HDV), the video format that was introduced in 2003 by JVC and Sony and records compressed HDTV video standard DV media, is a tricky beast. HDV video files are extremely small, but they present a set of challenges all their own. Fortunately, the new Final Cut Pro 6 can help tame the problem.

HDV has taken the indie film world by storm. Small, inexpensive cameras, such as Canon’s XH A1 and Sony’s HVR-V1U, offer great portability, easy access to HD image, and files small enough to edit on virtually any hard disk and computer. It’s a format perfectly designed for producers on low budgets.

The dilemma with HDV isn’t in the shooting; it’s in the editing. The problems all stem from those fanatically small files. In order to get them that small, camera manufacturers have made a number of compromises in time code accuracy, color fidelity, image quality, render quality and recompression speed.

If you are using HDV in a professional environment with many effects, compositing, color correction and integration with other video formats––or if you are under tight deadlines––HDV can drive you nuts. That’s where Final Cut Pro 6, and the ProRes 422 codec, can help out.

Keep in mind that at the instant the image is recorded to HDV tape, the visual quality of your image has been permanently altered. Transcoding (converting your video) into a different format won’t put back the visual information that’s been lost. But, what transcoding will do is improve the quality of any post-production effects and color correction, as well as speed rendering and final output.

When working with HDV at the professional level, the current mantra is to use the format for image acquisition, then convert out of HDV before beginning the editing process. The problem, again, is those small files.

As Table 1 illustrates, any video format you convert HDV into is going to take more space; in fact, a lot more space! Higher data rates also require faster drives. In an ideal situation, you should consider using RAID storage whenever you are working with HD media.
What is ProRes 422?

Table 1: Data rates and storage requirements for low-end HD video formats. (Note: Data rates and storage will vary based upon image size and frame rates.)

ProRes 422 is a new QuickTime codec released by Apple with Final Cut Studio 2. It has several major advantages over HDV, and one disadvantage. Table 2 compares key features in the two formats.

Table 2: A comparison of the benefits of using ProRes 422 vs. HDV. ProRes has better image quality, but a larger file size.

Integrating HDV with Other HD Media
If you are integrating HDV with other HD media, your best option is to convert the HDV to match it during capture. This requires a capture card capable of real-time media transcoding, such as the Kona 3 from AJA (www.aja.com), or the Decklink HD from Blackmagic Design (www.blackmagic-design.com). Transcoding during capture is especially important if you have a lot of HDV material to convert. Provided your hard disks are fast enough to keep up, the capture card will convert your HDV footage into any format you choose.

However, if you only have a few clips that need conversion, or if you have already captured your HDV footage using FireWire, for example, you will need to convert it into another video format using one of two methods: Batch Export or Media Manager.

While Media Manager will recompress your files, a better option is Batch Export. This allows you to group files from multiple open projects and export to a variety of different formats at the same time. It also exports at an extremely high quality and, frankly, it has an easier to understand interface.

Here’s how it works:

1) In the Browser, select the HDV clips you want to convert.

2) Choose File > Batch Export (see Figure 1).

Figure 1: The Batch Export window. Note the three buttons at the bottom.

3) Select the clip(s) in the Batch Export window you want to export, then click the Settings button (see Figure 2).

Figure 2: The Batch Export > Settings window. Note the three checkboxes at the bottom

4) Click the Set Destination button and specify where you want the files stored. In my case, I created a folder on my second drive called “Converted Files” to hold all my converted media.

5) From the Item Settings pop-up menu, select the video format you want to convert the files into. This video format should match the settings of your Final Cut project.

6) Check all three checkboxes at the bottom. “Recompress All Frames” makes sure all HDV frames are properly converted. “Make Self-Contained” makes sure your files can be played on any system. “Use Item In/Out” only converts the portion of the clip you’ve marked. If you want to convert the entire clip, make sure this is not checked.

7) Click OK.

8) At the bottom of the Batch Export window, click Export. On my MacBook Pro Core Duo 2, it took about two minutes to convert 30 seconds of HDV. However, as this process is fully automatic, once you’ve started the export, you can just let it run until the conversion is done.

Editing in HDV, Rendering in ProRes 422
While Batch Exporting has been an option in Final Cut Pro for a while, with the release of Final Cut Pro 6, HDV editors have a new choice. If you are editing a project that is all––or mostly––HDV, transcoding into another format doesn’t make a lot of sense. On the other hand, the lack of color fidelity for effects and the extremely slow conforming process prior to output or export can grow very old very quickly.

In Final Cut Pro 6, a new option has been added to the Sequence > Rendering tab which solves this issue. To select it, go to Sequence > Sequence Settings > Render Control (see Figure 3).

Figure 3: HDV sequences can now be rendered into ProRes 422 by selecting this option in the Sequences > Sequence Settings > Rendering tab.

To give you an idea of the benefits of using ProRes for your HDV sequences, I created a simple bevel effect and rendered it using HDV render settings and ProRes 422 settings. ProRes was 30 percent faster. I then timed how long it took to export the same effects sequence. It was close to a dead heat, but ProRes was slightly faster.

The benefit to rendering using ProRes is that you retain higher quality on your effects and color correction work. Plus, rendering is significantly faster. The downside is that your render files will be about four times bigger.

Deciding What to Do
So, what should you do? If you are editing HDV for the fun of it, or to learn more about the aesthetics of HD, then stay HDV native all the way. Final Cut Pro easily supports native HDV editing and you don’t need to worry about any format conversions.
If you are editing an HD program and integrating a limited number of HDV clips, convert the HDV clips to match your project using Final Cut’s Batch Export function.

If you are editing an HD program using a significant number of HDV clips, invest in a high-quality capture card and convert your HDV during capture in real-time to match the rest of your HD footage.

If you are editing a program that is principally HDV, stay with HDV, but change your render settings to render in ProRes 422. The image quality of your effects will be higher and your render speeds will be faster. Final output speeds will be about the same.

HDV provides lots of opportunities, along with lots of challenges for the editor. The more you understand about the format, the more successful you’ll be at integrating HDV into your projects.

Larry Jordan is an LA-based Apple-certified trainer in digital media with over 25 years experience as a television producer and director with national broadcast and corporate credits. He is the founder and editor-in-chief of Edit Well, the rich-media newsletter for Final Cut Studio, published by Peachpit Press, and the author of several Final Cut Pro books. Visit his website at www.larryjordan.biz.

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