Simple explanation of MQA "Origami" feature

If the source file is 44.1 kHz 16 bit, then the decoding information is in the area of the 15th bit that's below even the noise floor of the file. "Origami" (folding) is not implemented for such files.

If the source file is ≥88.2 kHz 24 bit, then 48 kHz 24 bit area captured (rectangle A):

...the decoding information is in the area of the 15th bit (green):

...the "origami" (folding) information (buried information above 48 kHz) is below the decoding information area till the 23rd bit (grey):

On Redbook capable devices it'll be played as 44.1 kHz 16 bit, the "origami" information area will be hidden in the decoding information area (green) which stays inactive below the noise floor:

On non-MQA devices with a software decoding (for example TIDAL, UAPP or HiBy Music with a non-MQA DAC), the decoding information area activates first unfold which implements the "origami" information area (grey) to restore the original file to 88.2-96 kHz (B) and it'll be played as 88.2-96 kHz 24 bit:

On MQA-enabled devices (renderer or decoder), the decoding information area activates further unfolds which implements the "origami" information area (grey) to restore the original file to its full size:

In summary, the information related to MQA decoding is always in the 15th bit for backward compatibly (to play back even on Redbook capable devices) and will be activated when needed. Right below it, till the last bit of the file, there is the "origami" information area. If not necessary, this area will be hidden in the decoding information area. Otherwise, it restores only a musical information (orange triangle) on renderer DACs or the full file size on decoder DACs:

I've just find out that the MQA staff has released a video with very clear explanation of how the "Origami" works. Hope, this will help people to better understand the codec's folding/unfolding feature: