Apple ProRes

Apple ProRes is a high quality, lossy video compression format developed by Apple Inc. for use in post-production that supports up to 8K. It is the successor of the Apple Intermediate Codec and was introduced in 2007 with Final Cut Studio 2.[1] The ProRes family of codecs use compression algorithms based on the discrete cosine transform (DCT) technique, much like the H.26x and MPEG standards.[2] ProRes is widely used as a final format delivery method for HD broadcast files in commercials, features, Blu-ray and streaming.

Overview

ProRes is a line of intermediate codecs, which means they are intended for use during video editing, and not for practical end-user viewing. This is achieved by only using intra-frame compression, where each frame is stored independently and can be decoded with no dependencies on other frames. The benefit of an intermediate codec is that it offers excellent random access performance in post-production applications, and retains higher quality than end-user codecs while still requiring much less expensive disk systems compared to uncompressed video. It is comparable to Avid's DNxHD codec or CineForm which offer similar bitrates and are also intended to be used as intermediate codecs. ProRes is a DCT scalar based[3] intra-frame-only codec and is therefore simpler to decode than distribution-oriented formats like H.264. In 2018 Apple added a new "ProRes RAW" (compressed Bayer filter) to Final Cut Pro X,[4] after Blackmagic Design implemented compressed Bayer as "CinemaDNG 3:1" and "CinemaDNG 4:1" in their cameras and DaVinci Resolve.[5]

ProRes-Overview

ProRes supports different data rates and different resolutions. All ProRes422-variants use Chroma subsampling of 4:2:2 at 10 Bit Color depth. ProRes 4444 and 4444 XQ samples color in the 4:4:4 schema with a color depth of 10 or 12 bits, and can optionally include an alpha channel.

resolutionfpsProRes 422
Proxy		ProRes 422
LT		ProRes 422ProRes 422
HQ		ProRes 4444

(without Alpha)		ProRes 4444
XQ
(without Alpha)
(points)(Hz)(Mbit/s)(Mbit/s)(Mbit/s)(Mbit/s)(Mbit/s)(Mbit/s)
720 × 057650i, 25p1228416192138
1280 × 072025p19426192138206
1440 × 108050i, 25p3273105157236354
1920 × 108050i, 25p3885122184275415
50p76170245367551826
2048 × 153625p58131189283425637
50p1172623775678501275
3840 × 216025p15134249273711061659
50p303684983147522123318
4096 × 216025p16236552478611801769
50p3237301049157323593539
5120 × 288025p20245665598314752212
50p4059121311196629494424

ProRes 422

Key features
  • 8K, 5K, 4K, UHD, 2K, HD (up to 1920×1080), & SD resolutions
  • 4:2:2 chroma subsampling
  • 10-bit sample depth
  • I frame-only encoding
  • Variable bitrate (VBR) encoding
  • Normal 147 Mbit/s and High-Quality 220 Mbit/s and ProRes (LT) 100Mbit/s as well as ProRes Proxy for HD 45Mbit/s for HD resolution at 60i
  • Normal 42 Mbit/s and High-Quality 63 Mbit/s for SD resolution at 29.97
  • Fast encoding and decoding (both at full size and half size)

ProRes 4444 and ProRes 4444 XQ

ProRes 4444 and ProRes 4444 XQ are lossy video compression formats developed by Apple Inc. for use in post-production and include support for an alpha channel.

ProRes 4444 was introduced with Final Cut Studio (2009)[6] as another in the company's line of intermediate codecs for editing material but not for final delivery. It shares many features with other, 422, codecs of Apple's ProRes family but provides better quality than 422 HQ in colour detail.[7] It has a target data rate of approximately 330 Mbit/s for 4:4:4 sources at 1920x1080 and 29.97 fps

ProRes 4444 XQ was introduced with Final Cut Pro X version 10.1.2 in June 2014. It has a target data rate of approximately 500 Mbit/s for 4:4:4 sources at 1920x1080 and 29.97 fps, and requires OS X v10.8 (Mountain Lion) or later.

Key features
  • 8K, 5K, 4K, 2K, HD (up to 1920×1080), & SD resolutions[8]
  • 4:4:4 chroma subsampling
  • Up to 12-bit sample depth for video
  • Variable bitrate (VBR) encoding
  • Alpha channel support at up to 16-bit sample depth

ProRes RAW

In April 2018 Apple released ProRes RAW. It is built upon the same technology as other ProRes codecs, but is directly applied to the raw data coming from the sensor, thus delaying the debayering process to the post-production stage. ProRes RAW therefore aims at quality and better colour reproduction, rather than performance.[9]

Playback

On 28 August 2008, Apple introduced a free ProRes QuickTime Decoder for both Mac and Windows that allows playback of ProRes files through QuickTime.

Open source projects

On 15 September 2011, FFmpeg introduced a free decoder for ProRes 422 for libavcodec.

FFmbc, a fork of FFmpeg customized for broadcast and professional usage, supports ProRes 422 and 4444 files.[10]

On 1 October 2011,[11] JCodec introduced an open source (FreeBSD License) pure Java decoder for ProRes 422, a translate[12] of FFmpeg version.

Encoding

Installing Final Cut Pro will install the ProRes codecs for encoding files on macOS. Without Final Cut Pro installed, QuickTime Player can also be used to capture ProRes 422 video from any compatible attached camera, using the "Maximum" quality setting when producing a Movie Recording.[13]

Apple released ProRes bundled with other pro codecs as a download for users with "qualifying copies of Final Cut Pro, Motion, or Compressor" installed, for OS X with QuickTime 7.6 and newer.[14]

At the April 2010 NAB Show, Digital Video Systems launched the first Windows 7 platform with the ability to encode to all the varieties of Apple ProRes at speeds far faster than real time on their Clipster product.[15]

On March 31, 2011, Telestream added support for ProRes encoding on Windows systems with Episode Engine, Vantage, and FlipFactory as a free upgrade to the current versions of these products. The system must be running on Windows Server 2008 and be able to support this feature. ProRes video capturing and output to tape is available in Telestream's Pipeline network encoder.

On 29 October 2011, FFmpeg introduced a free encoder, enabling ProRes 422 encoding on all FFmpeg supported platforms.

On 1 November 2011,[11] JCodec introduced an open source (FreeBSD License) pure Java encoder for ProRes 422.[16]

At the April 2012 NAB Show, Brevity introduced a customized algorithm for the accelerated transport and encoding of ProRes files.[17]

Frame layout

A typical ProRes 422 frame has the following layout:

Frame container atom
Frame header
Picture 1
Picture 2 (interlaced frames only)

ProRes hardware

The Arri Alexa has a built-in ProRes recording unit for its 1080p and 2K video streams, supporting ProRes 4444 and all ProRes 422 versions.

As of June 2011, several hardware-based ProRes encoders exist, from AJA Video Systems[18] (IO HD FireWire 800 interface; Ki Pro and Ki Pro Mini portable recorders, Ki Pro Rack and Ki Pro Ultra for 4K/UltraHD workflows), Atomos[19] (Ninja and Samurai recorders), Sound Devices (PIX series recorders), Convergent Designs (Odyssey7, 7Q, 7Q+), and Fast Forward Video[20] (Sidekick recorder).

At NAB 2012, Blackmagic announced ProRes recording support for their HyperDeck SSD recorders as well as onboard recording on the Blackmagic Cinema Camera, and Brevity announced a GPU-based ProRes transcoder with simultaneous accelerated file transport.[21]

In 2013 Blackmagic Design release Blackmagic Cinema Camera that record in raw and Prores files directly in camera 4:2:2 10bit.

In 2013 Convergent Design introduced their Odyssey7 and Odyssey7Q monitor/recorders that can record in Apple ProRes 422 (HQ) and are certified by Apple.[22]

In 2014 Atomos introduced their latest advanced recorder Shogun that can record 4K in Apple ProRes.[23]

In 2015 AJA introduced the CION production camera that can capture 4K/UltraHD/2K/HD to all Apple ProRes 422 formats as well as Apple ProRes 4444 in 12-bit.

In 2016 Blackmagic Design release UrsaMini 4.6k that can capture from 4.6k to HD in all Apple ProRes flavor from Proxy to 4444 in 12-bit.

In 2018/2019 Blackmagic Design release Pocket Cinema Camera 4K that can capture 4k/UltraHD/1080p in all Apple ProRes 422 formats.

The 2019 Mac Pro has a new "Apple Afterburner" card as an optional component to accelerate ProRes and ProRes RAW decoding.

See also

References
  1. "Final Cut Pro 6 - Broad Format Support". apple.com.
  2. "Apple ProRes 422 Codec Family". Library of Congress. 17 November 2014. Retrieved 13 October 2019.
  3. Adcock, Gary (2009-03-03). "ProRes: A Closer Look". ProVideo Coalition. Archived from the original on 2009-03-12. Retrieved 2009-03-12.
  4. "Final Cut Pro X update introduces ProRes RAW and advanced closed captioning". apple.com.
  5. Design, Blackmagic. "Media - Blackmagic Design". www.blackmagicdesign.com. Archived from the original on 2015-07-23. Retrieved 2018-04-11.
  6. "Final Cut Pro 7. Expanded ProRes Family". apple.com.
  7. Apple ProRes White Paper July 2009
  8. https://www.apple.com/final-cut-pro/docs/Apple_ProRes_White_Paper_December_2013.pdf
  9. Apple ProRes RAW White Paper April 2018, https://www.apple.com/final-cut-pro/docs/Apple_ProRes_RAW_White_Paper.pdf
  10. "Google Code Archive - Long-term storage for Google Code Project Hosting". code.google.com.
  11. JCode authors (2011-10-01). "JCodec site". Retrieved 2015-10-24.
  12. "jcodec/jcodec". GitHub.
  13. "Record a movie in QuickTime Player on Mac".
  14. "Pro Video Formats 2.0.4". support.apple.com.
  15. "Broadcast and Media". www.dvs.de.
  16. "jcodec/jcodec". GitHub.
  17. "NAB 2012: Brevity Emerges From Stealth Mode". Sports Video Group. 2012-04-16. Retrieved 2012-05-14.
  18. AJA Video Systems
  19. Atomos. "Atomos". www.atomos.com.
  20. "FFV - Fast Forward Video". www.ffv.com.
  21. http://sportsvideo.org/main/blog/2012/04/16/nab-2012-brevity-emerges-from-stealth-mode/
  22. "Recording in Apple ProRes 422(HQ) on the Odyssey7 and Odyssey7Q". convergent-design.com. Archived from the original on 2015-03-18., Retrieved from web.archive.org. March 18th, 2015.
  23. Atomos. "Shogun - Atomos". www.atomos.com.
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