1 files changed, 95 insertions, 0 deletions
diff --git a/module/grid/readjpg.m b/module/grid/readjpg.m
new file mode 100644
index 00000000..4576381c
--- /dev/null
+++ b/module/grid/readjpg.m
@@ -0,0 +1,95 @@
+Readjpg: module
+{
+
+	PATH: con "/dis/grid/readjpg.dis";
+
+	ImageSource: adt
+	{
+		width:	int;
+		height:	int;
+		origw:	int;
+		origh:	int;
+		i:		int;
+		jstate:	ref Jpegstate;
+		data:		array of byte;
+	};
+
+	Jpegstate: adt
+	{
+		# variables in i/o routines
+		sr:	int;	# shift register, right aligned
+		cnt:	int;	# # bits in right part of sr
+	
+		Nf:		int;
+		comp:	array of Framecomp;
+		mode:	byte;
+		X,Y:		int;
+		qt:		array of array of int;	# quantization tables
+		dcht:		array of ref Huffman;
+		acht:		array of ref Huffman;
+		Ns:		int;
+		scomp:	array of Scancomp;
+		Ss:		int;
+		Se:		int;
+		Ah:		int;
+		Al:		int;
+		ri:		int;
+		nseg:	int;
+		nblock:	array of int;
+		
+		# progressive scan
+		dccoeff:	array of array of int;
+		accoeff:	array of array of array of int;	# only need 8 bits plus quantization
+		nacross:	int;
+		ndown:	int;
+		Hmax:	int;
+		Vmax:	int;
+	};
+	
+	Huffman: adt
+	{
+		bits:	array of int;
+		size:	array of int;
+		code:	array of int;
+		val:	array of int;
+		mincode:	array of int;
+		maxcode:	array of int;
+		valptr:	array of int;
+		# fast lookup
+		value:	array of int;
+		shift:	array of int;
+	};
+		
+	Framecomp: adt	# Frame component specifier from SOF marker
+	{
+		C:	int;
+		H:	int;
+		V:	int;
+		Tq:	int;
+	};
+	
+	Scancomp: adt	# Frame component specifier from SOF marker
+	{
+		C:	int;
+		tdc:	int;
+		tac:	int;
+	};
+	
+	# Constants, all preceded by byte 16rFF
+	SOF:	con 16rC0;	# Start of Frame
+	SOF2:	con 16rC2;	# Start of Frame; progressive Huffman
+	DHT:	con 16rC4;	# Define Huffman Tables
+	RST:	con 16rD0;	# Restart interval termination
+	SOI:	con 16rD8;	# Start of Image
+	EOI:	con 16rD9;	# End of Image
+	SOS:	con 16rDA;	# Start of Scan
+	DQT:	con 16rDB;	# Define quantization tables
+	DNL:	con 16rDC;	# Define number of lines
+	DRI:	con 16rDD;	# Define restart interval
+	APPn:	con 16rE0;	# Reserved for application segments
+	COM:	con 16rFE;	# Comment
+
+	init : fn (disp: ref Draw->Display);
+	fjpg2img : fn (fd: ref sys->FD, cachepath: string, chanin, chanout: chan of string): ref Image;
+	jpg2img : fn (filename, cachepath: string, chanin, chanout: chan of string): ref Image;
+};
+\ No newline at end of file