REDCODE RAW: Evolution (DSMC2 to DSMC3) and Future (DSMC4?) – YMCinema

0

RED has released a white paper focusing on its codec, which is REDCODE RAW. Although this document is not new, it is quite updated and contains interesting information on the evolution of this compressed codec implemented in RED cameras, from the RED One to DSMC2 to DSMC3.

DSMC3 body

According to the REDCODE RAW white paper, this codec is not tied to any particular image data compression technology. RED states that the evolution of REDCODE RAW has followed the evolution of sensor and camera technology. As each new sensor RED has improved in the areas of colorimetry, resolution and dynamic range. Additionally, RED claims that the codec is being improved and adapted to meet these qualities. Read the white paper below:

REDCODE RAW - Frame rates compared to ProRes RAW and ProRes
REDCODE RAW – Frame rates compared to ProRes RAW and ProRes

As RED’s proprietary file format, REDCODE RAW (R3D) efficiently encodes image data in a way that maximizes post-production flexibility of RAW files while keeping file sizes manageable. When the RED ONE camera was launched in 2007, REDCODE RAW was the key advancement that made 4K digital video capture a practical reality. Today, with RED cameras capable of capturing 8K resolution, REDCODE is even more relevant for handling the massive amounts of information contained in ultra-detailed images.

The Red
The Red

Attempting to directly compress RAW image data from the sensor would be inefficient and lead to larger than necessary file sizes. REDCODE RAW manipulates RAW image data in a fully reversible process to make it more suitable for image compression. It is this manipulation that gives REDCODE RAW high quality images at small file sizes while retaining all the flexibility and power to work directly with uncompressed RAW image data. The REDCODE compression process takes the raw image data from the Bayer CFA (color filter array) model and separates the raw image data into four channels – one for red, two greens and blue in a quadruple Bayer . Once the raw image data is in this form, the pre-emphasis feature ensures that subsequent compression places the correct weight to preserve visibly important detail across the entire dynamic range. Then, the 4 channels are decorrelated before being sent to an image data compression engine.

The RED ONE Digital Cinema Camera
The RED ONE Digital Cinema Camera

The benefits of REDCODE RAW are the benefits of uncompressed RAW image data without the drawbacks of large file sizes and high data rates. Most image processing that transforms RAW image data into a viewable image will result in loss of information or precision. Matrix transforms to make colors correct for display will suppress or compress undisplayable colors, and tonal processing often suppresses dynamic range. White balancing on RAW data can be very effective at producing plausible highlight extensions in clipped regions, but once the image has been color corrected, these algorithms do not work. By still retaining reference to individual pixel values ​​on a color filter array (CFA) sensor, enhanced demosaicing and other pixel-level algorithms can be applied to further enhance the visual image. Expanded metadata support in REDCODE RAW format means that even early images shot with the RED ONE can benefit from updated image processing, as if they had been shot with the latest RED camera.

DSMC2 Unified Family
DSMC2 Unified Family

Image quality is a key part of the RED camera philosophy. REDCODE RAW preserves essential image details from the camera sensor – resolution and dynamic range. Many commonly used image processing operations, such as white balance, can be applied with greater precision and finesse to RAW image data. Always basing a desired color space output on the original RAW data allows for the most accurate conversion and best handling of out-of-gamut colors that cannot be achieved if an intermediate image color space is used.

The RED Monstro 8K VV
The RED Monstro 8K VV

Extensive third-party support for REDCODE RAW through the RED R3D SDK and in REDCINE-X Pro gives you the ability to edit the RAW development process non-destructively and is fully supported by all major post-production software packages such than Adobe, Apple, Avid , Resolution, etc. Non-destructive editing means altering decoded metadata via writing to a sidecar metadata file (.RMD) allowing you to set white balance and all color processing directly from the RAW image data. At all times, the original R3D RAW image data and metadata are retained. R3D Trim lets you create a still image or trimmed clip from a lossless R3D – it’s an exact copy of the original R3D file’s data, including all metadata.

Recording Time - 8K DSMC2 vs ARRIRAW and ProRes
Recording Time – 8K DSMC2 vs ARRIRAW and ProRes
Recording Time - V-Raptor vs ARRIRAW and ProRes
Recording Time – V-Raptor vs ARRIRAW and ProRes
Recording Time - RED Komodo vs Canon C300 Mark III and ProRes
Recording Time – RED Komodo vs Canon C300 Mark III and ProRes

Throughout post-production, different consumers of the image demand the image in different formats. REDCODE RAW facilitates this with fast image decoding at various resolutions, and the reference to linear raw data enables precise conversion to linear floating point formats such as EXR for VFX or ACES workflows, log encodings for calibration and fully finished images for preview or editorial.

In addition to offering greater image flexibility than ProRes recording, 8K R3D resolution at 5:1 offers a data rate somewhere between ProRes 4444 and 422HQ at 4k. 8K ProRes 4444 XQ takes nearly 3 times the data that an 8K R3D at 5:1 takes (see slides above).

V-Raptor versus its brother - the RED Komodo
V-Raptor versus its brother – the RED Komodo

The evolution of REDCODE RAW has followed the evolution of sensor and camera technology. As each new RED sensor has improved in the areas of colorimetry, resolution and dynamic range, REDCODE RAW has also improved and adapted to these qualities. As new metadata became available in the camera (gyroscopic orientation data for example), the R3D format expanded to encompass the new data and make it available through the R3D SDK to users and
apps. It is this flexibility and adaptability that will keep REDCODE RAW at the forefront of RAW recording as sensors and other camera technologies evolve.

Ambulance BTS: The RED Komodo Bayhem
Ambulance BTS: The RED Komodo Bayhem

REDCODE RAW is not tied to any particular image data compression technology. Since the development of RED One, REDCODE has used a wavelet transform as part of image compression. As the R3D SDK handles all decoding tasks, this allowed RED to seamlessly update the nuances of the codec to compress data more efficiently as sensors improved. Now RED has changed the wavelet compression transform to a discrete cosine transform (DCT). Although DCT is associated with JPEG, like wavelet transform, it takes the spatial image data in the frequency domain allowing efficient encoding of salient image data. Even with this change, the core philosophy and RAW recording of R3D remains the same, giving users the same benefits they have always enjoyed. Why the change? To apply a wavelet transform to an image, the entire image must be processed together. DCT divides the image into smaller blocks so that only a small part of the image needs to be processed together and reside in memory. Switching to DCT allows for greater electronic efficiency in compression with reduced electrical power requirements, with a concomitant reduction in heat generated and increased battery life. Similarly, efficiency gains can be made in decoding compressed data in post-production.

Abandoned Michael Bay Ambulance Trailer: FPV Cinema Rules.  Photo: Michael Bay's Instagram
Michael Bay during the filming of Ambulance. Camera: RED Helium 8K. Photo: Michael Bay’s Instagram

The first camera in the RED line to take advantage of DCT is the RED Komodo 6K. The benefits of reduced power requirements through DCT lend themselves perfectly to a camera like Komodo, where a small camera form factor is a top priority. This is yet another example of REDCODE’s flexibility to scale as camera needs change. As of November 2020, data rates for HQ, MQ and LQ can reach up to 280MB/s, ~175MB/s and ~110MB/s respectively with camera settings at 6K 17:9, 23.98 FPS.

Irix Cine 21mm T1.5 full frame lens on the RED Komodo.  Photo: Irix
Irix Cine 21mm T1.5 full frame lens on the RED Komodo. Photo: Irix

Although everyone expects RED’s patent for the compressed raw to expire in 2028, it seems that the technology continues to evolve and adapt to new generations of DSMC systems. Until then, we believe RED will launch its DSMC4 cameras paired with an even better compression methodology. Additionally, it also appears that the patent does not interfere with or prevent other camera manufacturers from implementing compressed raw in-house as well (Nikon Z9, Sony VENICE 2, etc.). Anyway, for now, REDCODE RAW is one of the most efficient codecs out there when it comes to in-station freedom combined with low data rates and low power consumption.

Product list

Here are the products mentioned in the article and the links to buy them from authorized retailers.

  • RED Komodo 6K Digital Cinema

Share.

Comments are closed.