Difference between revisions of "Apple ProRes"

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ProRes algorithm is based on the [[Discrete_Cosine_Transform | Discrete cosine transform]] (further DCT) and utilizes the following compression techniques:
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* custom hybrid [[Golomb|Golomb-Rice]] / [http://en.wikipedia.org/wiki/Exponential-Golomb_coding Exponential Golomb] coding for DCT coefficients
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* [[Run_Length_Encoding|run-lenght coding]]
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* [[Differential_Coding|differential coding]]
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* [[Scalar_Quantization|scalar quantization]]

Revision as of 13:49, 30 September 2010

ProRes Introduction

Apple ProRes is a family of video codecs used for storing and editing high definition video data in Apple's Final Cut Pro. Apple's official whitepaper lists the codec's key features as being:

  • intra-only codecs
  • 4:2:2 / 4:4:4:4 source material
  • 10-bit (12-bit for ProRes 4444) sample depth
  • variable bitrate

Technical documentation on ProRes 422 Standard Definition / High Quality codec

ProRes 422 SD/HQ is the same codec operating on two different bitrates (flavours). Two different FOURCCs are used in order to indicate each flavour:

Flavour name FOURCC Bitrate
Standard Definition (SD) 'apcn' 145 Mbps
High Quality (HQ) 'apch' 220 Mbps

ProRes algorithm is based on the Discrete cosine transform (further DCT) and utilizes the following compression techniques: