PPPA or GGGA
I have been notified that a mode is used by recent SLA printers (light projectors?). Apparently, it's named PPPA or GGGA. It looks like it means for each 3 gray bytes, a single byte is assigned for alpha. I'm told it is the native image space used by monochrome displays.
Question
I'm already aware of RGBA. It means after 3 bytes of red, green, and blue then there is one byte for alpha or transparency.
But I cannot wrap my head around the PPPA/GGGA. How does it make sense?
- In the case of RGBA:
- The 4 bytes of RGBA are describing a single pixel.
- But in the case of PPPA/GGGA:
- The first 3 bytes describe 3 pixels. Right?
- The fourth - last - byte describes the transparency for all the 3 pixels.
- Am I right? I'm confused.
