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+# QMK QGF/QFF RLE data schema :id=qmk-qp-rle-schema
+
+There are two "modes" to the RLE algorithm used in both [QGF](quantum_painter_qgf.md)/[QFF](quantum_painter_qff.md):
+
+* Non-repeating sections of octets, with associated length of up to `128` octets
+ * `length` = `marker - 128`
+ * A corresponding `length` number of octets follow directly after the marker octet
+* Repeated octet with associated length, with associated length of up to `128`
+ * `length` = `marker`
+ * A single octet follows the marker that should be repeated `length` times.
+
+Decoder pseudocode:
+```
+while !EOF
+ marker = READ_OCTET()
+
+ if marker >= 128
+ length = marker - 128
+ for i = 0 ... length-1
+ c = READ_OCTET()
+ WRITE_OCTET(c)
+
+ else
+ length = marker
+ c = READ_OCTET()
+ for i = 0 ... length-1
+ WRITE_OCTET(c)
+
+```