Tools for working with the reMarkable notes format and API.
Status: This is very much work in progress. The basic functionality should work but there will be some bugs and missing features. Use at your own risk ;-)
This has been tested with the reMarkable 2 on Linux.
A command line tool is included which serves as a example on how the API works. It should also be useful on its own:
lslists the content from the devicegetdownloads notes as PDF filesputuploads PDF documents to the devicepinallows to set or remove bookmarks
The CLI tool uses the reMarkable cloud API.
The parser supports the v3 format for reMarkable notes.
The rm format is the proprietary format used by the
reMarkable tablet. The format is used to store
drawings made on the tablet.
The format is documented in the unofficial reMarkable Wiki.
In version 5, each .rm file contains one page.
Each page consists of several layers which contain the strokes that make up
the image.
The file consists of a simple header followed by the data. The data is structured into layers, strokes and dots.
All numeric values are little endian.
The header length is 43 bytes and contains ASCII encoded text:
reMarkable .lines file, version=5
The remaining bytes are filled with whitespace.
The header is immediately followed by 4 bytes for a 32 bit unsigned integer
which gives us the number of layers.
The next 4 bytes are again a 32 bit unsigned integer for the number of
strokes in the first layer.
Each stroke consists of the stroke data followed by the data for the dots. A stroke has the following attributes:
| Size | Datatype | Description |
|---|---|---|
4 bytes |
uint32 |
Brush Type |
4 bytes |
uint32 |
Color |
4 bytes |
uint32 |
Padding? |
4 bytes |
float32 |
Brush Size |
4 bytes |
- | unknown (v5 only) |
4 bytes |
uint32 |
Number of Dots |
The data for the individual dots follows immediately after.
The Brush Types refer to the different "pencil" choices available on the tablet. The values are different for the v3 and the v5 format.
| Version | Brush | ID |
|---|---|---|
| v3 | Paint Brush | 0 |
| v3 | Pencil | 1 |
| v3 | Ballpoint | 2 |
| v3 | Marker | 3 |
| v3 | Fineliner | 4 |
| v3 | Highlighter | 5 |
| v3 | Eraser | 6 |
| v3 | Mechanical Pencil | 7 |
| v3 | Eraser | 8 |
| v5 | Brush | 12 |
| v5 | Mechanical Pencil | 13 |
| v5 | Pencil | 14 |
| v5 | Ballpoint | 15 |
| v5 | Marker | 16 |
| v5 | Fineliner | 17 |
| v5 | Highlighter | 18 |
The Color is either Black (0), Gray (1) or White (2).
The Brush Size is the selected base size of the brush
(not to be confused with the effective width of the stroke).
Predefined sizes are Small (1.875), Medium (2.0) and Large (2.125).
Each dot holds the following attributes:
| Size | Datatype | Description |
|---|---|---|
4 bytes |
float32 |
X-Coordinate |
4 bytes |
float32 |
Y-Coordinate |
4 bytes |
float32 |
Speed |
4 bytes |
float32 |
Tilt |
4 bytes |
float32 |
Width |
4 bytes |
float32 |
Pressure |
After the last byte of the dot data is read, The data for the next layer begins, starting with the number of strokes.
The Coordinates range between 0,0 and 1404,1872,
the origin is at the top left corner.
Speed is a measure for how fast the stylus is drawn across the surface. Not sure how this would affect something (maybe the density of the stroke?).
The Pressure values ranges from 0.0 to 1.0.
The Width seems to be the effective width of the brush, already accounted for tilt and pressure.
Not quite sure if this is correct. Depending on the Brush type and size, pressure and tilt should determine the actual width of the stroke.
The Tilt value is the angle of the stylus towards the tablet surface.
It is given in radians and ranges in two intervals
from 0.0 to 1.5708 (0 to 90 degrees)
and from 4.7124 to 6.2832 (270 to 360 degrees).
The render package contains methods to render drawings to a bitmap (PNG)
or PDF.
This "basically works" but the rendering output does not quite match the original.
- Some lines are way to thin/weak, others to strong.
- When Rendering a drawing as an overlay on an existing PDF, the scale and placement of the drawing is off.
The api package contains an implementation for the reMarkable cloud API,
including a client for websocket notifications.
If the tablet is connected to the API, one can access folders and documents through that API and also upload or modify content. Changes made through the API will by synced to the tablet.
This is a personal project. It is not associated with the reMarkable company.
Sources:
- https://plasma.ninja/blog/devices/remarkable/binary/format/2017/12/26/reMarkable-lines-file-format.html
- https://github.com/juruen/rmapi/
- https://www.reddit.com/r/RemarkableTablet/comments/7c5fh0/work_in_progress_format_of_the_lines_files/
- https://github.com/splitbrain/ReMarkableAPI/wiki
- https://gitlab.com/wrobell/remt