Colour Pipeline
Definition
The sequence of transformations applied to raw sensor data to produce the encoded video signal, including white balance, gamma curve, colour space conversion (e.g. BT.601 vs BT.709), and chroma subsampling ratio. The combination is device-specific and recorded in the container metadata.
- Stages
- White balance, gamma curve, colour space conversion, chroma subsampling
- Colour space example
- BT.601 versus BT.709
- Specificity
- Device-specific
- Where recorded
- Container metadata
Common questions
Why is the colour pipeline useful for matching video to a source camera?+
Because the exact sequence and parameters of white balance, gamma, colour space, and chroma subsampling are set by the device manufacturer and firmware, a questioned video's pipeline signature can be compared against a known device to support or exclude it as the source.
What can disrupt a colour pipeline comparison?+
Re-encoding or transcoding through a different application, social media platform, or messaging app typically strips or rewrites the original metadata and reprocesses the colour space, which can erase or overwrite the original device's pipeline signature.
Related terms
- Bitrate Profile
- The pattern of bitrate variation across time in a variable-bitrate recording. A camera's rate-control algorithm allocates more bits to complex scenes and...
- Codec Fingerprint
- The characteristic pattern of encoding decisions made by a camera's firmware when compressing video: the specific H.264 or H.265 profile and level,...
- GOP (Group of Pictures) Structure
- The pattern of I-frames, P-frames, and B-frames in a compressed video stream. Different cameras use different GOP lengths and frame-type ratios, which...
- PRNU (Photo Response Non-Uniformity)
- The unique pattern of pixel-level sensitivity variations in a camera sensor, used as a device fingerprint. A genuine camera-original image carries the...
- Reference Profile
- A database of known parameter values built from recordings made with the suspect device under controlled conditions. Comparison of the questioned video...