<pngtester.cgi> v0.8a May 3 2001

This is a CGI script that tabulates, as HTML, the information
of chunks contained in one or more PNG, JNG and MNG files.

History:

v0.8  May 2 2001 -- PPLT was supported. A subroutine was replaced
                    by unpack("Hx",xxx) code.
v0.8a May 3 2001 -- Wrong comment, when IDAT chunks came
                    continuously, was mended.

Supported chunks (v0.8 and later):

MHDR, IHDR, DHDR, JHDR, BASI, BACK, PLTE, DEFI, FRAM, TERM,
IDAT, LOOP, ENDL, SHOW, MOVE, CLON, CLIP, DISC, PAST, MAGN,
SAVE, SEEK, PROM, DROP, DBYK, ORDR, PPLT, gAMA, sBIT, sRGB,
sPLT, iCCP, tIME, cHRM, eXPI, fPRI, nEED, bKGD, hIST, tRNS,
pHYs, tEXt, zTXt, iTXt

* iCCP, zTXt, iTXt -- Neither compressed data nor UTF8-encoded
                     data can be shown yet.

Usage:

http://(path)/pngtester.cgi?Filename1[&Filename2][&Filename3]...

Call pngtester.cgi from your browser, and this CGI will read
one or more files (designated by Filenames1, 2, 3, etc.) and
tabulates the information of chunks contained in the file(s)
as follows:
==> Testing file "1.png"
PNG Bytes Chunk Data CRC
IHDR 13 24 x 24, 4 bits, palletted, basic filter, not interlaced OK
PLTE 48 16 pallet entries:
#000000, #800000, #008000, #808000, #000080, #800080, #008080, #c0c0c0, #808080, #ff0000, #00ff00, #ffff00, #0000ff, #ff00ff, #00ffff, #ffffff		 OK
IDAT 62 32K window size, default argorithm OK
IEND 0 @ OK

==> Testing file "2.png"
PNG Bytes Chunk Data CRC
IHDR 13 24 x 24, 4 bits, palletted, basic filter, not interlaced OK
PLTE 48 16 pallet entries:
#000000, #800000, #008000, #808000, #000080, #800080, #008080, #c0c0c0, #808080, #ff0000, #00ff00, #ffff00, #0000ff, #ff00ff, #00ffff, #ffffff		 OK
IDAT 58 32K window size, default argorithm OK
IEND 0 @ OK 

<addtRNS.cgi> v0.4c April 28 2001

This is a CGI script that adds a tRNS chunk to a PNG image and
displays the tRNS-including PNG image without writing the tRNS
chunk into the PNG file.

If there has been already any tRNS chunk in this PNG file,
this CGI replaces the tRNS chunk with a new one and displays
the new tRNS-including PNG image without writing the tRNS chunk
into the PNG file.

The new tRNS-including PNG image generated by this CGI will be able
to be saved as a new file through your clicking the right button
of a mouse on the image.

Usage:

1. To add a tRNS chunk to a PNG image with 8- or 16-bit RGB color
   depth,
	addtRNS.cgi?-t(Transparent color)-n(Filename)
   in which (Transparent color) is 6 or 12 hexadecimal digits, and
   (Filename) is the name of a PNG file.
   The hexadecimal digits are in a range of from 000000 to ffffff
   in the case of 8-bit RGB color depth or in a range of
   from 000000000000 to ffffffffffff in the case of 16-bit RGB color
   depth.
   -- eg. addtRNS.cgi?-tffffff-nSAMPLE.png
   -- eg. addtRNS.cgi?-tffffffffffff-nSAMPLE.png

2. To add a tRNS chunk to a PNG image with 1-, 2-, 4-, 8- or 16-bit
   grayscale depth,
	addtRNS.cgi?-g(Transparent gray)-n(Filename)
   in which (Transparent gray) is 1, 2 or 4 hexadecimal digits, and
   (Filename) is the name of a PNG file.
   The hexadecimal digits are in a range of from 0 to 1 in the case
   of 1-bit grayscale depth, in a range of from 0 to 3 in the case
   of 2-bit grayscale depth, in a range of from 0 to f in the case
   of 4-bit grayscale depth, in a range of from 00 to ff in the case
   of 8-bit grayscale depth or in a range of from 0000 to ffff
   in the case of 16-bit grayscale depth.
   -- eg. addtRNS.cgi?-gf-nSAMPLE.png
   -- eg. addtRNS.cgi?-gff-nSAMPLE.png
   -- eg. addtRNS.cgi?-gffff-nSAMPLE.png

3. To add a tRNS chunk to a PNG image with palleted color,
	addtRNS.cgi?-p(Index1,Alpha1[/Index2,Alpha2]...)-n(Filename)
   in which each Index represents a pallet index of one or two
   hexadecimal digits, each Alpha representes intransparency of one
   or two hexadecimal digits, and (Filename) is the name of
   a PNG file.
   The hexadecimal digits for each Index are in a range of from 00
   to ff.  The hexadecimal digits for each Alpha are also in a range
   of 00 to ff (00 shows transparency, and ff shows intransparency).
   -- eg. addtRNS.cgi?-p00,00/05,00-nSAMPLE.png

4. To obtain image information from a PNG file,
	addtRNS.cgi?-n(Filename)
   in which (Filename) is the name of the PNG file.
   -- eg. addtRNS.cgi?-nSAMPLE.png

In case of 4, image information is displayed as follows:
Bit Depth: 4 bits
Color Type: 3 (paletted)
Pallet Entry= 16
0001020304050607
||||||||
#000000#800000#008000#808000#000080#800080#008080#c0c0c0
08090a0b0c0d0e0f
||||||||
#808080#ff0000#00ff00#ffff00#0000ff#ff00ff#00ffff#ffffff

No tRNS chunk
<txtcut.cgi> v0.3 May 2 2001

This is a CGI script that removes all textual chunks (tEXt, zTXt, iTXt)
from a PNG image and displays the resulting PNG image without changing
the original PNG file.

If you want to save the resulting image, you can save this image as a new
file through clicking the right button of a mouse on this image.

* txtcut.cgi v0.2c and before -- iTXt is'nt contained in the textual chunks
that can be removed by txt.cgi.

Usage:

http://(Path)/txtcut.cgi?Filename

Filename is the name of a PNG file from which you want to remove
textual chunks.