#
# The EBNF grammar for the JNG-1.0 standard chunks in JNG datastreams
# Version: 0.4
# Author: Cosmin Truta, Jan 2001
# Contributing author: Glenn Randers-Pehrson
#

jng_standalone_datastream	::=
	jng_signature jng_datastream

jng_signature	::=
	"\213JNG\r\n\32\n"

jng_datastream	::=
	JHDR jng_image_info jng_image_data png_general_info IEND

jng_image_info	::=
	(jng_image_info_chunk | png_color_info_chunk | png_general_info_chunk)*

jng_image_data	::=
	jng_primary_image_data (JSEP jng_altern_image_data)?

png_general_info	::=
	(png_general_info_chunk)*

jng_primary_image_data	::=
	((JDAT | IDAT)* (JDAT) (JDAT | IDAT)*) |
	((JDAT | JDAA)* (JDAT) (JDAT | JDAA)*)

jng_altern_image_data	::=
	(JDAT)+

jng_image_info_chunk	::=
	bKGD | pHYs

png_color_info_chunk	::=
	cHRM | gAMA | iCCP | sRGB

png_general_info_chunk	::=
	tIME | iTXt | tEXt | zTXt