+#}
+
+# ---------------------------------------------------------------------------- #
+# #
+# QOI encoder #
+# #
+# ---------------------------------------------------------------------------- #
+# #
+# Transliteration of: #
+# https://github.com/phoboslab/qoi/blob/master/qoi.h #
+# #
+# Copyright (c) 2021, Dominic Szablewski - https://phoboslab.org #
+# SPDX-License-Identifier: MIT #
+# QOI - The "Quite OK Image" format for fast, lossless image compression #
+# #
+# ---------------------------------------------------------------------------- #
+
+class qoi_rgba_t(Structure):
+#{
+ _pack_ = 1
+ _fields_ = [("r",c_uint8),
+ ("g",c_uint8),
+ ("b",c_uint8),
+ ("a",c_uint8)]
+#}
+
+QOI_OP_INDEX = 0x00 # 00xxxxxx
+QOI_OP_DIFF = 0x40 # 01xxxxxx
+QOI_OP_LUMA = 0x80 # 10xxxxxx
+QOI_OP_RUN = 0xc0 # 11xxxxxx
+QOI_OP_RGB = 0xfe # 11111110
+QOI_OP_RGBA = 0xff # 11111111
+
+QOI_MASK_2 = 0xc0 # 11000000
+
+def qoi_colour_hash( c ):
+#{
+ return c.r*3 + c.g*5 + c.b*7 + c.a*11
+#}
+
+def qoi_eq( a, b ):
+#{
+ return (a.r==b.r) and (a.g==b.g) and (a.b==b.b) and (a.a==b.a)
+#}
+
+def qoi_32bit( v ):
+#{
+ return bytearray([ (0xff000000 & v) >> 24, \
+ (0x00ff0000 & v) >> 16, \
+ (0x0000ff00 & v) >> 8, \
+ (0x000000ff & v) ])
+#}
+
+def qoi_encode( img ):
+#{
+ data = bytearray()
+
+ print(F" . Encoding {img.name}.qoi[{img.size[0]},{img.size[1]}]")
+
+ index = [ qoi_rgba_t() for _ in range(64) ]
+
+ # Header
+ #
+ data.extend( bytearray(c_uint32(0x66696f71)) )
+ data.extend( qoi_32bit( img.size[0] ) )
+ data.extend( qoi_32bit( img.size[1] ) )
+ data.extend( bytearray(c_uint8(4)) )
+ data.extend( bytearray(c_uint8(0)) )
+
+ run = 0
+ px_prev = qoi_rgba_t()
+ px_prev.r = c_uint8(0)
+ px_prev.g = c_uint8(0)
+ px_prev.b = c_uint8(0)
+ px_prev.a = c_uint8(255)
+
+ px = qoi_rgba_t()
+ px.r = c_uint8(0)
+ px.g = c_uint8(0)
+ px.b = c_uint8(0)
+ px.a = c_uint8(255)
+
+ px_len = img.size[0] * img.size[1]
+
+ paxels = [ int(min(max(_,0),1)*255) for _ in img.pixels ]
+
+ for px_pos in range( px_len ):
+ #{
+ idx = px_pos * img.channels
+ nc = img.channels-1
+
+ px.r = paxels[idx+min(0,nc)]
+ px.g = paxels[idx+min(1,nc)]
+ px.b = paxels[idx+min(2,nc)]
+ px.a = paxels[idx+min(3,nc)]
+
+ if qoi_eq( px, px_prev ):
+ #{
+ run += 1
+
+ if (run == 62) or (px_pos == px_len-1):
+ #{
+ data.extend( bytearray( c_uint8(QOI_OP_RUN | (run-1))) )
+ run = 0
+ #}
+ #}
+ else:
+ #{
+ if run > 0:
+ #{
+ data.extend( bytearray( c_uint8(QOI_OP_RUN | (run-1))) )
+ run = 0
+ #}
+
+ index_pos = qoi_colour_hash(px) % 64
+
+ if qoi_eq( index[index_pos], px ):
+ #{
+ data.extend( bytearray( c_uint8(QOI_OP_INDEX | index_pos)) )
+ #}
+ else:
+ #{
+ index[ index_pos ].r = px.r
+ index[ index_pos ].g = px.g
+ index[ index_pos ].b = px.b
+ index[ index_pos ].a = px.a
+
+ if px.a == px_prev.a:
+ #{
+ vr = int(px.r) - int(px_prev.r)
+ vg = int(px.g) - int(px_prev.g)
+ vb = int(px.b) - int(px_prev.b)
+
+ vg_r = vr - vg
+ vg_b = vb - vg
+
+ if (vr > -3) and (vr < 2) and\
+ (vg > -3) and (vg < 2) and\
+ (vb > -3) and (vb < 2):
+ #{
+ op = QOI_OP_DIFF | (vr+2) << 4 | (vg+2) << 2 | (vb+2)
+ data.extend( bytearray( c_uint8(op) ))
+ #}
+ elif (vg_r > -9) and (vg_r < 8) and\
+ (vg > -33) and (vg < 32 ) and\
+ (vg_b > -9) and (vg_b < 8):
+ #{
+ op = QOI_OP_LUMA | (vg+32)
+ delta = (vg_r+8) << 4 | (vg_b + 8)
+ data.extend( bytearray( c_uint8(op) ) )
+ data.extend( bytearray( c_uint8(delta) ))
+ #}
+ else:
+ #{
+ data.extend( bytearray( c_uint8(QOI_OP_RGB) ) )
+ data.extend( bytearray( c_uint8(px.r) ))
+ data.extend( bytearray( c_uint8(px.g) ))
+ data.extend( bytearray( c_uint8(px.b) ))
+ #}
+ #}
+ else:
+ #{
+ data.extend( bytearray( c_uint8(QOI_OP_RGBA) ) )
+ data.extend( bytearray( c_uint8(px.r) ))
+ data.extend( bytearray( c_uint8(px.g) ))
+ data.extend( bytearray( c_uint8(px.b) ))
+ data.extend( bytearray( c_uint8(px.a) ))
+ #}
+ #}
+ #}
+
+ px_prev.r = px.r
+ px_prev.g = px.g
+ px_prev.b = px.b
+ px_prev.a = px.a
+ #}
+
+ # Padding
+ for i in range(7):
+ data.extend( bytearray( c_uint8(0) ))
+ data.extend( bytearray( c_uint8(1) ))
+ bytearray_align_to( data, 16, 0 )
+
+ return data
+#}