tag Radiance images as scRGB

They aren't always, but scRGB is also 0-1 range, so conveniently this
now works:

	vips copy car-stack-eighth.hdr x.jpg

TODO

@@ -1,3 +1,5 @@
+- does radiance import give 0-1 RGB images? we could tag them as scRGB
+
 - now we've removed round-to-nearest from NN, we need something extra in the
   affine transform to displace the input cods
 

libvips/colour/rad2float.c

@@ -1,10 +1,13 @@
 /* Convert Radiance 32bit packed format to float.
+ *
  * 3/3/09
  * 	- from LabQ2Lab and Radiance sources
  * 2/11/09
  * 	- gtkdoc 
  * 20/9/12
- * 	redo as a class
+ * 	- redo as a class
+ * 13/12/12
+ * 	- tag output as scRGB, since it'll be 0-1
  */
 
 /*
@@ -196,7 +199,7 @@ vips_rad2float_init( VipsRad2float *rad2float )
 	VipsColourCode *code = VIPS_COLOUR_CODE( rad2float );
 
 	colour->coding = VIPS_CODING_NONE;
-	colour->interpretation = VIPS_INTERPRETATION_sRGB;
+	colour->interpretation = VIPS_INTERPRETATION_scRGB;
 	colour->format = VIPS_FORMAT_FLOAT;
 	colour->bands = 3;
 

libvips/foreign/radiance.c

@@ -6,6 +6,8 @@
  * 	- add radiance write
  * 20/12/11
  * 	- reworked as some fns ready for new-style classes
+ * 13/12/12
+ * 	- tag RGB rad images as scRGB
  */
 
 /*
@@ -900,7 +902,7 @@ rad2vips_get_header( Read *read, FILE *fin, VipsImage *out )
 	vips_image_set_string( out, "rad-format", read->format );
 
 	if( strcmp( read->format, COLRFMT ) == 0 )
-		out->Type = VIPS_INTERPRETATION_RGB;
+		out->Type = VIPS_INTERPRETATION_scRGB;
 	else if( strcmp( read->format, CIEFMT ) == 0 )
 		out->Type = VIPS_INTERPRETATION_XYZ;
 	else

libvips/iofuncs/header.c

@@ -441,6 +441,7 @@ vips_image_guess_interpretation( const VipsImage *image )
 	case VIPS_INTERPRETATION_CMC: 
 	case VIPS_INTERPRETATION_LCH: 
 	case VIPS_INTERPRETATION_sRGB: 
+	case VIPS_INTERPRETATION_scRGB: 
 	case VIPS_INTERPRETATION_YXY: 
 		if( image->Bands < 3 )
 			sane = FALSE;