REDCODE

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R3D file
R3D file icon
Filename extension .R3D
Type code R3D
Magic number DRED
Developed by Red Digital Cinema Camera Company
Type of format Media container
Container for Audio, Video, TimeCode, metadata

REDCODE RAW (R3D) is a proprietary multimedia audio/video file format owned by the Red Digital Cinema Camera Company and features a visually lossless compression for video contents and uncompressed audio contents.[1][2][3] It is used as native recording format of RED digital cameras and recorded on proprietary hard disk drives, CompactFlash cards or SSD drives.

Overview[edit]

All Red cameras record only in the REDCODE RAW codec, which is a constant-bitrate wavelet codec.

Unlike cameras that record RGB data, RED cameras record compressed Bayer data. Recording compressed raw data allows white balance, gamma and other image processing parameters to be set during post-production. Adjusting these settings directly in-camera does not impact the raw data that is actually recorded, but rather modifies metadata recorded alongside recorded images. These meta-settings, called "Looks", can be saved and applied to the camera's outputs. Applying Looks allows on-set crew to see an image that more closely represents the director of photography's vision of the image, rather than the "flat" look of the raw image data that comes from the sensor by default. Since Looks only affect metadata, the recorded files offer flexibility for post-production.

Compression algorithm[edit]

Video streams within a R3D file are stored as a series of images, each independently compressed in the wavelet-based JPEG2000 format.[3] Each image has four channels (color planes), corresponding to the Bayer pattern of the sensor: 1 for red, 2 for green, 1 for blue.[2][3] Each frame is compressed to the same target size (the video is coded with a variable bit-rate) without dependencies on other frames (only intraframe compression is used).

Decoding to RGB consists of two steps: decompression of the data, followed by demosaicing. The demosaicing algorithm interpolates the four quarter-resolution color planes, corresponding to the Bayer pattern, to three full-resolution color planes, 1 red, 1 green, and 1 blue.

Audio streams (mono, stereo or 4-channels) are coded, uncompressed, in plain 48 kHz, 24-bit PCM.

References[edit]

  1. ^ "Overview of the REDCODE File Format". Red Digital Cinema Camera Company. 2012-10-03. Retrieved 2014-03-13. 
  2. ^ a b "REDCode". MultimediaWiki. 2012-01-22. Retrieved 2014-03-13. 
  3. ^ a b c Schlaile, Peter. "libredcode". Retrieved 2014-03-13. 

External links[edit]