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2 recording codec, Recording codec – ARRI ALEXA 35 Body & PL Mount Set (LBUS) User Manual

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Recording

51

Compact Drive LED States

LED State

Media State

Solid Green

Drive is in standby, ready to record and safe to remove.

Solid Red

Read/write access during Playback or Recording. Do not remove the drive.

Info:

As recording is stopped, it takes a few seconds to finalize the recorded clip. During this time, the drive

should not be removed.

Blue flashing

Drive is being loaded or unloaded.

Red flashing

Drive error, see

MENU > Alerts

for details.

Off

Drive cannot be accessed. Please try reinserting the drive. If the problem persists, check the drive state with

Codex Device Manager.

Media Info

► Select

MENU > Info > Media Info

for additional information on the inserted medium.

12.2 Recording Codec

MXF (Material eXchange Format)

Both ARRIRAW and Apple ProRes files are recorded in an MXF (Material eXchange Format) container.

An MXF container file can “wrap” different types of video and audio material along with associated

metadata. The internal structure of these files is defined by the Operational Patterns (OP). Our cameras

create MXF files with OP1a structure, which packages picture, sound and metadata into a single file.

This structure is ideal for both camera acquisition and archiving, since audio, video and metadata is

always kept together and virtually no data gets lost if recording is unexpectedly interrupted. OP1a also

is a streaming format, which means that even incomplete files can be repaired and accessed up to the

last recorded frame.

ARRIRAW

ARRIRAW data delivers unencrypted, uncompressed and uncompromised image quality. It offers

the highest achievable resolution, the camera's natural color response and exposure latitude as

uncompressed and unprocessed sensor data. ARRIRAW images have only one channel. A color

reconstruction algorithm calculates the missing components of each pixel based on the type and

position of the array of colored filters (Bayer pattern) on the camera sensor.
ARRIRAW de-bayering is available through the ARRI Imaging SDK only, which is implemented in the

ARRI Reference Tool (ART) and most of the major post production tools for dailies processing and

mastering.
The camera will automatically calculate a CRC32C checksum for the image data inside each

ARRIRAW frame. This checksum is recorded as part of the image header and can be used by software

like the ARRI Reference Tool, to verify that the ARRIRAW image content has not changed during any

copy step. Note that this checksum does not validate the entire file, only the image data. Note that

during the download from the Compact Drive to a computer or afterwards it is possible to reduce the

size of ARRIRAW files by up to 40% using Codex High Density Encoding (HDE) technology with the

ARRIRAW HDE Transcoder app.

Apple ProRes

Recording in Apple ProRes is a cost efficient alternative to shooting ARRIRAW, as it requires less

storage space and no further processing in post.

Info:

Apple ProRes is a variable bit rate (VBR) codec. Depending on the content of your images the

remaining recording time on the recording media can be shorter or longer than indicated by the camera.