04/18/2007, 12:30pm, EDT
Wednesday, April 18th
Apple details ProRes 422 video format
"For years now, Final Cut Pro editors have relied on HD formats such as DVCPRO-HD and HDV for native, real-time multistream editing. The efficiency and image quality of these workflows are excellent for content that originates with and can be finished natively in these formats. But such formats were designed under significant camcorder engineering constraints, so they limit the full quality that can be carried in an HD signal."
As noted by AppleInsider, Apple's new format is said to work with HD on slower drives, and with more users on shared storage. Quality is indistinguishable from most pristine sources, according to Apple, even after multiple encoding/decoding generations. The format offers full width of 1920x1080 and 1280x720 resolution alongside 4:2:2 chroma sampling to provide precise compositing and blending at sharp saturated color boundaries.
A 10-bit sample depth preserves subtle gradients of 10-bit sources such as sunsets or graphics with no visible banding artifacts, and I frame-only encoding ensures consistent quality in every frame with no artifacts from complex motion, according to the Cupertino-based company.
Apple ProRes 422 features variable bit-rate (VBR) encoding which analyzes the image and allocates more bits to complex frames, increasing efficiency by not wasting excess bits on simple frames. The format offers two target HD bit rates with normal quality targeted at 145Mbps and high quality (HD) targeted at 220Mbps. Apple notes that low bit rates increase the affordability of equipment, enabling users to edit more streams with more real-time effects on slower drives or have more users accessing the same media over Xsan.
The format is designed for speed, according to Apple, with full-size and 1/2-by-1/2-size decoding speed for more effects and more streams. Additionally, users can capture ProRes 422 in real time from any HD-SDI source with improved encoding speed.
Filed under: software
Other story tags: video editing
,
, 4
,
,
,
,
,

subscribe to comments
for this article
Try this:
keeps
getting
funnier