FORMAT



XDCAM HD422

Recording Format XDCAM HD422 is still popular for Factual Production.

The Sony XDCAM HD codec was released in 2008. It is used in a wide range of cameras and recorders. Based on XDCAM HD, the 422 variant is the highest quality in this family. With a colour sub-sampling of 4:2:2, as opposed to 4:2:0 with XDCAM HD, a Full HD resolution of 1920x1080 (1440x1080 in XDCAM HD) and a higher data rate of at least 50 Mbits/s, the aim of this codec is to provide a higher quality format for broadcast applications. The bandwidth of the signal is only 8 bits. These parameters mean XDCAM HD422 is roughly comparable to the Sony ½ inch magnetic tape format HDCAM (not to be confused with HDCAM SR ).

Compression within XDCAM HD422 is achieved using the MPEG2 codec (4:2:2 Profile @ High Level), which introduces a Long GOP structure. GOP stands for Group of Pictures and clarifies the inter-frame structure of MPEG2. This means that not every frame is encoded individually but that intermediate images are interpolated according to a recurring pattern and saved into storage.

Stored in either XDCAM or HD 422, it is rewritable onto Sony’s Professional Disc storage format, an optical disc available in sizes of 23GB, 50GB, and 128GB.  The latter version is only able to be "written once". These discs are very robust and offer fairly good archival properties. The Sony SxS memory cards can also be used and are available in capacities ranging from 32 to 256GB and support write speeds of 800Mbits/s to 3.5GBits/s.

XDCAM HD422 video and audio files are wrapped, along with associated metadata, in  industry-standard MXF (Material eXchange Format) OP1a containers. The XDCAM HD422 format can be processed natively in all major editing and post-production systems. Due to the MPEG2 encoding this is a computationally intensive codec requiring fast processors, particularly if the edit involves material across many tracks of video. It is advisable to use the software Sony offers for viewing proxies and managing data.  It is very important to maintain the prescribed Sony folder structure for all XDCAM variants.

XDCAM HD422 Summary

  • VIDEO
  • Bit depth: 8 Bit
  • Compression: MPEG2 422P @HL Interframe
  • Compression Ratio: approx. 20:1
  • Chroma Subsampling: 4:2:2
  • Aspect Ratio: 16:9
  • Resolutions:
  • 1920x1080 @ 23.98p, 25p, 29.97p, 50i, 59.94i1280x720 @ 23.98p (Pull-down), 25p, 29.97p, 50p, 59.94p
  • Video Bit Rate: 50 MBit/s
  • Video Interface: HD-SDI, IEEE1394, Gigabit-Ethernet
  • AUDIO
  • Channels: 8 channels
  • Encoding: PCM at 48kHz / 24 Bit
  • STORAGE
  • File Structure: MXF (OP1-a)
  • Recording Media: Sony Professional Discs, Sony SxS cards

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