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|
#SNG: This is a synthetic SNG test file
# Our first test is a paletted (type 3) image.
IHDR: {
width: 16;
height: 19;
bitdepth: 8;
using color: palette;
with interlace;
}
# Standard gamma
gAMA: {0.45}
# The parameters are the standard values in the Specification section 4.2.2.3.
cHRM {
white: (0.31270, 0.32900);
red: (0.6400, 0.3300);
green: (0.3000, 0.6000);
blue: (0.1500, 0.600);
}
# This cannot coexist with the iCCP chunk.
# sRGB {1} # This value conveys `relative colorimetric' intent.
# This cannot coexist with the sRGB chunk.
# First four bytes of profile must be the big-endian length of the remainder.
# Real profiles at <http://pmt.sourceforge.net/iccp/>.
iCCP {
name: "dummy profile";
profile: hex 00 00 00 05 01 02 03 04 05;
}
# Sample bit depth chunk
sBIT: {
red: 8;
green: 8;
blue: 8;
# gray: 8; # for non-color images
# alpha: 8; # for images with alpha
}
# An example palette -- three colors, one of which we will render transparent
PLTE: {
(0, 0, 255)
(255, 0, 0)
"dark slate gray",
}
# Set a background color
bKGD: {
# red: 127;
# green: 127;
# blue: 127;
# gray: 127; # for non-color images
index: 0; # for paletted images
}
# Frequencies, for rendering by viewers with small palettes
hIST: {23, 55, 10}
# Set transparency (for some reason this triggers a libpng CRC error)
tRNS: {
255; # Render the first color in the palette fully transparent
# red: 70;
# green: 70;
# blue: 70;
}
# Test the pHYs chunk; this data isn't really meaningful for the image
pHYs: {
xpixels: 500;
ypixels: 400;
per meter;
}
# Dummy timestamp
tIME {
year: 1999;
month: 11;
day: 22;
hour: 16;
minute: 23;
second: 17;
}
# Dummy offset
oFFs {
xoffset: 23;
yoffset: 17;
unit: micrometers
}
# Dummy physical calibration data
pCAL {
name: "dummy physical calibration data";
x0: 1234;
x1: 5678;
mapping: linear;
unit: "BTU";
parameters: 55 99;
}
# Dummy screen calibration data
sCAL {
unit: meter;
width: 0.002;
height: 0.001;
}
# Suggested palette
sPLT {
name: "A random suggested palette";
depth: 8;
(0, 0, 255), 255, 7;
(255, 0, 0), 255, 5;
( 70, 70, 70), 255, 3;
}
# The viewer will actually use this...
IMAGE: {
pixels base64
2222222222222222
2222222222222222
0000001111100000
0000011111110000
0000111001111000
0001110000111100
0001110000111100
0000110001111000
0000000011110000
0000000111100000
0000001111000000
0000001111000000
0000000000000000
0000000110000000
0000001111000000
0000001111000000
0000000110000000
2222222222222222
2222222222222222
}
tEXt: { # Ordinary text chunk
keyword: "Title";
text: "Sample SNG script";
}
zTXt: { # Compressed text chunk
keyword: "Author";
text: "Eric S. Raymond";
}
# The production releases of libpng don't support this yet.
#
#iTXt: { # International UTF-8 keyword
# language: "en";
# keyword: "Description";
# translated: "Description:"
# text: "SNG demo, illustrating the language syntax";
#}
gIFg { # GIF Graphic Extension chunk
disposal: 23;
input: 17;
delay: 55;
}
gIFx { # GIF Application Extension chunk
identifier: "SNGCOMPI";
code: "SNG";
data: "Dummy application data\n"
"illustrating assembly of multiple strings\n";
}
private prIv {
"Test data for the private chunk";
}
# Test file ends here
|
