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Blue_MiSfit · 11th December 2019, 01:15

I always figured the 10 bit 4:2:2 thing most likely goes back to SDI / HD-SDI which was traditionally 10 bit 4:2:2. Capturing the full bandwidth of this signal into a file based format in a way that's perceptually lossless was long since considered "good enough" and widely used mezzanine file formats like ProRes do a great job of this - especially relative to the old days of 50-80 Mbps 1080p MPEG-2 service masters.

Given the context of final distribution always being 8 bit 4:2:0 until recently, perceptually lossless 10 bit 4:2:2 was indeed always good enough.

Now that we're doing HDR, 10 bit is mandatory, and 12 or even 16 bit (ProRes 4444 / 4444 XQ or JPEG 2000) is common for source material when encoding for Dolby Vision. Sure, this gets shaped into a 10 bit IPT file but allegedly more of the input can be recovered after Dolby magic.

Studio archival masters are generally 16 bit full range RGB TIFFs or the OpenEXR equivalent (not sure about the specifics of that), and probably DPX for older stuff. Maybe 16 bit lossless JPEG 2000 if the studio is IMF native.

11th December 2019, 01:15	#2033 \| Link
Blue_MiSfit Derek Prestegard IRL Join Date: Nov 2003 Location: Los Angeles Posts: 5,989	I always figured the 10 bit 4:2:2 thing most likely goes back to SDI / HD-SDI which was traditionally 10 bit 4:2:2. Capturing the full bandwidth of this signal into a file based format in a way that's perceptually lossless was long since considered "good enough" and widely used mezzanine file formats like ProRes do a great job of this - especially relative to the old days of 50-80 Mbps 1080p MPEG-2 service masters. Given the context of final distribution always being 8 bit 4:2:0 until recently, perceptually lossless 10 bit 4:2:2 was indeed always good enough. Now that we're doing HDR, 10 bit is mandatory, and 12 or even 16 bit (ProRes 4444 / 4444 XQ or JPEG 2000) is common for source material when encoding for Dolby Vision. Sure, this gets shaped into a 10 bit IPT file but allegedly more of the input can be recovered after Dolby magic. Studio archival masters are generally 16 bit full range RGB TIFFs or the OpenEXR equivalent (not sure about the specifics of that), and probably DPX for older stuff. Maybe 16 bit lossless JPEG 2000 if the studio is IMF native. Last edited by Blue_MiSfit; 13th December 2019 at 04:21.