Apple Pro Training Series. Optimizing Your Final Cut Pro System. A Technical Guide to Real-World Post-Production

In the world of nonlinear editing, a large and ever-growing number of formats are available for both online and offline editing. However, they can be broken down into three groups: standard definition video (SD), high definition video (HD), and data files from a film scanner.

Standard Definition (SD)

Standard definition video is the bulk of the transmission or delivery infrastructure into our homesfor example, cable TV or antennae. In North America and Japan, this analog format is known as NTSC (National Television Standards Committee); in most other regions, it's known as PAL (Phase Alternating Line); and in France and Russia, it's known as SECAM (SEquential Couleur Avec Mémoire). For the purposes of these chapters, we will discuss NTSC and PAL because these transmissions constitute the majority. (See the section on frame rates and standards in Lesson 7 for more information.)

PAL and NTSC have different aspect ratios and frame rates. Arming yourself with detailed technical information about the broadcast standards of each of these formats and understanding their differences will greatly assist you in the design of your project workflow. NTSC analog video, when translated or encoded into its digital uncompressed format (referred to as D1), has a frame size of 720 x 486 pixels running at 29.97 frames per second (fps) non-drop frame (NDF), and it is also known as 30 fps drop-frame (DF). (See the section on timecode DF versus NDF in Lesson 7 for more information). PAL and its uncompressed digital format has a frame size of 720 x 576 pixels running at 25 fps.

Assuming a 10-bit sample depth, the D1 NTSC video data rate is 27 MB/second (megabytes per second) and can be considered unwieldy because of its large file size. As a consequence, codecs (compression decompression) were developed to compress this data rate with varying degrees of artifacts (depending on the specific codec in use). One of the most common codecs is DV25, otherwise referred to as digital video (DV). You find this codec on consumer and prosumer mini DV tape formats. DV25 codec was developed in conjunction with IEEE-1394, or FireWire, and takes advantage of the FireWire architecture. (For more on codecs and compression, see Lesson 7, and for more on FireWire, see Lesson 9.) Many Final Cut Pro users will work with some form of DV via FireWire; it's fast becoming the de facto standard for nonlinear editing.

High Definition (HD)

High definition is increasingly available to residential consumers via satellite TV, digital cable TV, and over antennae. Although HD TV comes in many forms and formats, the two most common formats are 720p and 1080i. 720p has a frame size of 1280 x 720 running at 24, 30, or 60 fps progressive scan; 1080i has a frame size of 1920 x 1080 running at 59.94 fps interlaced scan. (See Lesson 7 for more details.)

Although HD formats offer increased spatial resolution over SD, it's increasingly common that 720p 24 replaces film acquisition for video delivery due to its film-like qualities (progressive scan and film frame rate). 1080i 59.94 with its increased temporal resolution is more appropriate for fast motion sporting events acquisition.

Final Cut Pro supports many established HD formats and will probably support new formats as they are introduced. HD formats come in a vast array, so prior to making your final acquisition or post-facility decision (whichever may come first), make sure that all the post-production facilities you plan to use are compatible. Remember that not all formats are supported in all locations, and a particular format may require specific playback equipment.

Data Files

Data files are created when you scan a film negative with a film scanner. These data files are most often used in a process called a digital intermediate, or DI. The term comes from the process of transferring a film project from a film negative (analog) to hard drives (digital) then back onto film negative (analog) for distribution; hence the name digital intermediate.

You can generate data files at any point in your process, but timing determines if you work online or offline. If you scan the negative and use the scanned files as your media, never to return to the original negative, and output using the same scanned files, then your workflow is online. The important aspect of using data files in an online workflow is that once you have converted the image on the negative to a digital format, you no longer need to maintain any reference to the original negative. The data files have such a high resolution that instead of going back to the film negative for release, a new negative is created using the files. By using data files to capture your film negative, you can adjust color and create transitions, as well as add visual effects without compromising the quality of the original image.

If you scan the negative and use the scanned files as a "reference" to the original negative, and you plan to return to the original negative for final output, then your workflow is offline.

There are many flavors of film formats, but data files generally come in two standard resolutions for 35mm full camera aperture scanning: 2K (2048 x 1536 pixels) and 4K (4096 x 3072 pixels). 2K scans are considered roughly equal to film resolution; 4K scans are usually reserved for visual effects shots and shots that require extra sharp focus.

Even though the resolution of online formats varies from 720 x 480 to 4096 x 3072, the common thread is that they are all used in online workflows. Therefore, we can consider all these formats roughly equal when designing a workflow. The real difference is how much quality you want and how much equipment you can afford. The online 2K and 4K resolutions are outside the capabilities of the current version of Final Cut Pro. However, offline workflows for 2 K and 4 K resolutions can always be designed with lower resolution media; you can create and edit resolutions lower than 2K and 4K and return them in the form of an EDL (edit decision list) or cut list for your negative cutter to complete the finished film. (See Lessons 4 and 6 for more information.)