Essential knowledge on handling the digital negative
ARRICORE is ARRI’s next-generation recording format, designed to meet the evolving needs of modern film production. Built on over a century of imaging expertise and engineered for the ALEV4 sensor's exceptional 17 stops of dynamic range, ARRICORE delivers high image quality with great workflow flexibility. It is designed to preserve the full creative intent from lens to grade.
The visual fidelity ARRI is known for, combined with highly efficient compression. This means you get the best of both worlds: cinematic image quality and a significantly reduced data footprint – 50% smaller than ARRIRAW. Whether you're on set or in post, ARRICORE integrates seamlessly into your existing pipeline.
RGB processed in-camera
ARRICORE is not a RAW format: Debayering to RGB and compression take place in-camera. But ARRICORE retains essential postproduction flexibility by using ARRI's REVEAL color pipeline. Therein exposure, white balance, and color tint are applied non-destructively during capture and can be changed in post.
REVEAL ensures maximum creative and technical control through delivering RGB LogC4 image to the software. REVEAL is part of ARRI’s Image Software Development Kit (SDK), which our partners use to develop ARRICORE (and ARRIRAW) in their softwares.
Ready for editorial – no transcoding needed
ARRICORE is designed for direct use in editorial environments. Its smart proxy capabilities allow for instant previews and lightweight editing, accelerating your workflow from camera to cut. No need for time-consuming conversions—just shoot, edit, and create.
Creative control built in
Similar to ARRIRAW, ARRICORE retains the flexibility filmmakers expect from ARRI: combined with ARRI Look File 4 and ARRI Textures, it gives cinematographers full creative control from capture to final grade.
Seamless integration with ARRI tools
ARRICORE is fully supported by the ARRI Image SDK and the ARRI Reference Tool (ART), ensuring smooth playback, look management, and metadata access across platforms. It’s also part of the ARRI Partner Program, making it easy for third-party tools to adopt and support the format.
Download our up-to-date 3rd-party compatibility overview for ARRICORE, ARRIRAW and more.
Frequently Asked Questions
We have collected the first daring questions on ARRICORE!
White paper
Further details can be found in the ARRICORE white paper.
Backwards compatibility
ARRICORE is exclusively available to ALEXA 35 Xtreme and future camera systems. It is not backwards compatible with ALEXA 35 or ALEXA Mini LF.
The ARRI Reference Tool (ART) is a software application (for Windows or Mac) that provides a graphical user interface for ARRI’s Image SDK. ART is a combined tool for viewing, rendering, metadata, and look files.
Learn more and download your copy of the ARRI Reference Tool!
ARRIRAW is ARRI’s format for uncompressed, unencrypted, and uncompromised sensor data. It can be considered a digital version of the camera negative. ARRIRAW fully retains the camera's natural color response and great exposure latitude as unprocessed sensor data.
Like film negative, ARRIRAW data has to be developed – or rather processed. The processing step converts the sensor readout into a color image suitable for normal viewing. ARRIRAW conserves the originally recorded raw data for later use, providing the flexibility to go back and refine the results at any time. This makes ARRIRAW an ideal format for digital cinematography and high-quality visual effects production.
Our camera line-up supports in-camera recording of ARRIRAW or MXF/ARRIRAW data. MXF/ARRIRAW is ARRIRAW within a container format (*.mxf), allowing each clip to be contained in just one file, as opposed to several thousand files, because with the regular ARRIRAW format (*.ari) every single frame is a separate file.
Older ALEXA cameras (ALEXA Classic, ALEXA Plus/Plus 4:3, ALEXA M, and ALEXA Studio) require an ARRI-certified external ARRIRAW recorder which understands the T-Link signal.
Debayering – The first phase of ARRIRAW processing is the most compute intensive. ARRIRAW images (like all CMOS sensor raw images) have only one ‘color’ channel (in fact, it’s a color-coded luminance channel). A color reconstruction algorithm calculates the missing components for each pixel based on the type and position of colored filters on the camera sensor. ARRI cameras use the Bayer pattern color filter array. The term 'color reconstruction' therefore is also known as ‘debayering’. The Bayer pattern filters the light hitting the sensor so that 50% of the sensor’s photosites are used to represent green, 25% of the photosites represent red, and the remaining 25% represent blue. Therefore, the debayer algorithm needs to reconstruct 75% of red, 50% of green, and 75% or blue color information:
The image above shows a single-channel capture from the sensor on the left, and the reconstructed image on the right. Utilizing the information about its color filter array, half of the reconstructed image's green values are interpolated from the surrounding photosites rather than captured, as are three-quarters of the red and three-quarters of the blue.
The output quality of the image depends on the debayering algorithm. Generally speaking, a simpler algorithm will process faster, but will also involve a higher probability of color errors. ARRI developed and maintains its own debayer algorithm (ARRI Debayer Algorithm, or ADA for short). ADA is available in the ARRI Reference Tool and third-party applications using our SDK.
For VFX, however, the images are often processed using the native sensor pixel count and then downscaled to e.g. 4K or 2K at a later stage. Using this approach takes advantage of the luminance resolution, which correlates to the sensor pixel count.
ARRI has built long-term relationships with postproduction equipment manufacturers through the ARRI Partner Program. These relationships have facilitated all of the leading compositing and color correction tools being able to process ARRIRAW files out of the box.
ARRIRAW in third-party implementations
With the introduction of our latest technologies, we no longer recommend implementing a custom ARRIRAW debayering or processing pipeline. The ARRI Image SDK provides the official, fully validated reference implementation and is designed to meet the performance, quality, and compatibility requirements of modern workflows.
For the vast majority of applications, the ARRI Image SDK is fast, reliable, and flexible enough to integrate seamlessly without the need for proprietary or custom processing solutions. The ARRI Image SDK ensures consistent image quality across all products and guarantees alignment with ARRI’s color science and ARRIRAW specifications.
Developers who join the ARRI Partner Program gain access to the SDK, accompanying documentation, and technical support. This eliminates the need to build and maintain custom ARRIRAW processing code, while providing a future-proof and fully supported integration path.
The ARRI Reference Tool (ART) is a software application (for Windows or Mac) that provides a graphical user interface for ARRI’s reference SDK. ART is a combined tool for viewing, rendering, metadata, and look files. It combines and therefore replaces the ARRIRAW Converter, ARRI Color Tool, and ARRI Meta Extract.
Learn more and download your copy of the ARRI Reference Tool!
Once you have chosen your workflow for an upcoming production, ARRI recommends running tests rather than assuming that things should work. So, ask yourself:
ARRI provides sample footage of all our cameras via FTP server or cloud service.
CODEX High Density Encoding (HDE) is a lossless, variable bitrate encoding scheme for ARRIRAW data. It reduces file sizes by over 40% without sacrificing image quality or metadata. It actually delivers a bit-exact match to the original files when it's decoded. HDE makes ARRIRAW easier to handle—cutting storage costs and speeding up transfers while remaining fully transparent to software using the ARRI Image SDK.
Supported by leading content providers and postproduction applications, HDE is widely used on ARRIRAW data shot with any ARRI ALEXA and AMIRA camera. CODEX state that to date, their macOS software has served over 39 billion HDE images.
The HDE process does not require user interaction. It happens in the background and on-the-fly, as the files are copied from the original recording media. For ALEXA 35, 35 Xtreme and ALEXA 265, it is also possible to encode files at a later point in time with the ARRIRAW HDE Transcoder. Learn more…
ALEXA XT, SXT, LF and 65 cameras are recording ARRIRAW data as a sequence of individual ‘.ari’ files. Each file containing a complete set of static (per-take) and dynamic (per-frame) camera and lens metadata.
ALEXA Mini, AMIRA and ALEXA Mini LF package everything into one MXF file per take. This removes metadata redundancies and significantly improves the efficiency when the original camera files need to be moved or archived.
With the introduction of the ALEXA 35 and REVEAL Color Science, we enhanced the image processing chain and fully aligned it with the metadata handling in MXF files. This led to a restructured, metadata-rich MXF container. Mapping of the ARRIRAW bitstream and carriage of ARRI system metadata in MXF files are defined in SMPTE RDD 54 and 55. The new MXF format is used by the ALEXA 35, 35 Xtreme and the ALEXA 265.
CODEX originally encoded HDE files into frame-based '.arx' sequences for all cameras up to ALEXA Mini LF. With the introduction of REVEAL Color Science, they also adopted MXF output, which is now available for ALEXA Mini, AMIRA, ALEXA Mini LF, ALEXA 35, ALEXA 35 Xtreme and the ALEXA 265.
High Density Encoding is a fully automated process that requires no additional steps from the user. The encoder is built into CODEX Device Manager, a macOS menu bar tool which runs a background service that makes the use of HDE as straightforward as offloading ARRIRAW data from the camera recording media:
If this workflow cannot be used, ARRIRAW HDE Transcoder offers an alternative. Learn more…
In 2010, ALEXA was the first digital motion picture camera on the market offering in-camera recording of Apple ProRes files onto SxS PRO cards, providing the full range of codecs from Apple ProRes 422 Proxy to Apple ProRes 4444 and later 4444 XQ. We called this "direct-to-edit", becuase MacBooks of that time featured an internal card reader to offload the SxS PRO cards.
In 2019, ALEXA Mini LF introduced a new method for recording Apple ProRes: sound, images, and metadata are no longer wrapped inside a QuickTime *.mov container but use the common MXF (Material eXchange Format) container.
MXF is an open standard that is widely supported and allows for more flexible access to metadata. Using the same container also allows us to record ARRIRAW and Apple ProRes to the same drive without reformatting. Apple is supporting MXF/Apple ProRes. They have published the "SMPTE RDD 44:MXF – Mapping and Application of Apple ProRes" (on IEEE.org).
ARRI cameras that currently support QuickTime/Apple ProRes will continue to use QuickTime.
Recording clips in Apple ProRes 4444 XQ preserves the full sensor quantization in logarithmic encoding, with the same range of colors available in ARRIRAW. Images recorded in a 4:4:4 codec are almost indistinguishable from uncompressed HD or UHD material. This makes internal recording attractive to feature film productions for the big screen, too. Recording in any of the high-end 4:2:2 codecs provides perfect source material for web or TV applications.
Please Note:
Apple ProRes is a variable bitrate codec, therefore a longer recording time than initially indicated on the camera may be possible.
Apple ProRes White Paper (2022)
