Visual QuickStart Guide [Electronic resources] : Final Cut Express HD for Mac OS X

Lisa Brenneis

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  • Capturing HDV Video

    The HDV capture scheme in Final Cut Express HD is Apple's first pass at devising a simple capture process for HDV. HDV uses MPEG-2that's the same compression used in iDVDto squeeze the extra-large HD datastream down to a size that can be handled without an additional video card. MPEG-2 compression reduces the size of the HDV datastream by reducing the number of frames that contain complete picture information. One of these complete frames (called I-frames) is followed by a sequence of reduced-image-data frames (called B-frames and P-frames).

    As you capture, FCE converts the HDV footage to Apple Intermediate Codec (AIC) format. AIC generates complete image and audio information for each frame. FCE attempts to perform this format conversion in real time, but unless you are running a top-of-the-line G5, the conversion will probably lag behind capture. The HDV capture process is similar to Capture Nowyou must manually cue up the footage you want to capture using your HDV camcorder's controls. For more information, see Apple's

    New Features in Final Cut Express HD PDF.

    HDV Capture Setup Checklist

    Here's a pre-capture checklist to help make your HDV capture go smoothly:

    • Is your HDV camcorder properly connected and powered on?

    • Have you selected the correct Easy Setup? You should select the setup that matches the frame size and frame rate of the HDV footage you want to capture.

    • Does your selected scratch disk have enough room to accommodate your captured footage? 1080i60 HDV can require up to 46 gigabytes of storage per hour of captured footagethat's nearly four times the space required to store an hour of captured DV.

      Table 5.1 lists storage requirements for DV and HDV. Note that AIC file sizes are approximate; more detail and motion in your HDV images will generate larger AIC-processed files. Static shots with large blocks of plain surface will generate smaller files.

      Table 5.1. DV and HDV Storage Requirements

      FORMAT

      FRAME SIZE

      STORAGE R

      EQUIREMENT

      DVNTSC

      720:480

      12 GB per hour

      DV PAL

      720:576

      12 GB per hour

      720p30 HDV (processed as AIC)

      1280:720

      23 GB per hour

      1080i60 HDV (processed as AIC)

      1440:1080

      46 GB per hour

      1080i50 HDV (processed as AIC)

      1440:1080

      38 GB per hour

    • Is your Capture Now time-limit set properly? The Capture Now time-limit setting on the Scratch Disks tab of the System Settings window should specify a time limit not much longer than the longest clip you're planning to capture.

    • Have you set a capture folder for your captured HDV clips? The project tab in the Browser is the default capture folder destination. If you want to create a separate capture folder in your project, control-click a folder in the Browser window, then choose Set Capture Folder from the shortcut menu.

    To capture an HDV clip:

    1.

    Read and follow the setup process described in "Setting Up for Capture" earlier in this chapter.

    2.

    Use your HDV camcorder's controls to locate the HDV footage you want to capture in this clip, and then rewind 5-7 seconds and pause the tape.

    3.

    Choose File > Capture, or press Command-8.

    The HDV Capture dialog box appears.

    4.

    In the HDV Capture dialog box, enter a name for the clip you're about to capture, then click Capture (Figure 5.21 ).

    Figure 5.21. Enter a name for the HDV clip, and then click Capture.

    The capture preview window appears as FCE starts videotape playback of your cued tape (Figure 5.22 ). During capture, FCE converts the HDV datastream to AIC format. The capture preview window displays the AIC-encoded video. FCE attempts to process in real time, but the speed of the conversion process depends on your Mac's processor speed and available RAM. A status message at the bottom of the capture preview window indicates whether the conversion process is occurring in real time (Figure 5.23 ), or is lagging behind capture.

    Figure 5.22. The HDV capture preview window displays video as it's encoded to Apple Intermediate Codec (AIC) format.

    [View full size image]

    Figure 5.23. The capture preview window's status message indicates this capture is being converted to AIC in real time.

    5.

    To stop capturing, press the Escape key; then, stop playback on your camcorder.

    The captured clip appears in the designated capture folder on the project's tab in the Browser.

    6.

    Play the clip to make sure it contains the video you want.

    Tips

    • To abort an HDV capture, press the Escape key twice.

    • FCE's HDV capture includes a scene detection feature that works just like iMovie's. During the AIC-encoding process, FCE automatically creates a separate clip (and a separate media file on disk) each time it detects a Start/Stop (Record/Pause) signal in captured HDV datastream (Figure 5.24 ).

      Figure 5.24. FCE's scene detection feature generated these four discrete Browser clips from a single capture. Each clip references a discrete AIC format media file on disc.

    • Apple warns users that FCE HD cannot capture reliably from a tape that has been recorded initially in one format (such as an HDV format), and then recorded over in another video format (such as DV). This caution extends to material recorded in two different formats of HDV, such as 720p30 followed by 1080i60. Try to capture from mixed format tapes and you could see dropped and frozen frames galore. Take Apple's advice and black and code (completely re-record) any tape before trying to record over it in another format. Or better yet, crack open a fresh tape.