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# BayerJPEG
The BayerJPEG is a strange format used by the Light L16... *sometimes*. We don't yet know when it switches from it's normal packed 10-bit raw format to this, or why.
### BayerJPEG Header
| size | type | meaning |
| ------- | ------ | ------- |
| 4 bytes | String | Magic Number "BJPG" |
| 4 bytes | u32 | *Format type* <br/> 0: colour <br/> 1: for monochrome |
| 4 bytes | u32 | Length of Jpeg 0 |
| 4 bytes | u32 | Length of Jpeg 1 |
| 4 bytes | u32 | Length of Jpeg 2 |
| 4 bytes | u32 | Length of Jpeg 3 |
| 1552 bytes | | unknown |
***Foramt Type: Monochrome***
Jpeg0 contains a full resolution grayscale image
***Format Type: Colour***
The bayered image is split across the four Jpeg, one
for each colour location.
I.E. an image from the ar1335 sensor, color filter bggr, you'd get
- 1 jpeg for the blue channel
- 2 jpeg for each green location
- 1 jpeg for the red channel
It's not currently known if these are in the order you'd expect.
***Considerations***
When the L16 decides to use BayerJPEG, it has to save four copies of each frame. A JPEG is limited to a bit depth of eight, but the sensors output 10-bit data. In order to not loose 75% of the precision, they seemingly divide the image into fours and expect you to sum them later.
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