sRGB

Developed by HP and Microsoft in 1996, sRGB (Standard Red Green Blue) is the standard color space for web content and consumer-grade digital cameras. It is based on the same primaries and has the same gamut as Rec. 709 but specifies a different transfer function.

Rec. 709

Also known as BT.709, Rec. 709 is a standard developed by the International Telecommunication Union (ITU) for high-definition television (HDTV) systems. It defines the color space, frame rates, and resolution for HDTV, ensuring uniformity in broadcast and production. Rec. 709 shares the same primaries and white point as sRGB but generally is regarded as having a different gamma or transfer function.

While sRGB and Rec. 709 share the same color primaries and white point, they differ in their transfer functions (gamma curves). sRGB is designed for typical office and home viewing conditions with an equivalent gamma of approximately 2.2, while Rec. 709 is tailored for television viewing environments with a gamma of around 2.4. This distinction affects how images are encoded and displayed, making it essential to use the appropriate color space for the intended medium to ensure accurate color reproduction.

Other Notable Color Spaces

SMPTE-C: Replaced the NTSC standard for standard-definition (SD) content in regions like the US, maintaining the D65 white point for consistent color reproduction.

EBU Tech. 3213-E: Superseded PAL for SD content in regions where PAL was previously used, ensuring smooth and accurate colors for standard-definition broadcasting.

Rec. 2020: Supports the widest color gamut for consumer media, covering almost all visible colors using three primaries. It is the standard for UltraHD Blu-ray and HDR content. Although current displays cannot fully reproduce Rec. 2020, it represents the future of color accuracy.