The Internet Archive is a crucial tool for my research. Without it, understanding the companies, locations, dates, and people related to the CIS/COD image format would have been close to impossible. It also archived much of the software to handle the images that was available online in the 1990s.

Thanks to my former colleague Helge Holzmann, who works at the Internet Archive, we are now able to analyse the CIS/COD images that have been archived by the Internet Archive. Helge extracted a list of 1552 URLs that hosted files with the MIME type “image/cis-cod” from the Internet Archive’s collection.

This list is based on the MIME type which the HTTP servers delivered in their HTTP response’s “Content-Type” field during crawling. So I was curious as to how many of those files are actually CIS/COD images. The first step in finding that out is to download these files and this worked for 1230 of the 1552 listed files.

The script actually does a bit more, by already checking the first three bytes of each file for the magic marker “CIS”:

three=$(head -c3 "${tmpfname}")
if [ "${three}" = "CIS" ]; then
    mimetype="image_cis-cod"
fi

It then assigns the MIME type “image/cis-cod” to those files and for all other files uses file --brief --mime-type to determine the MIME type. The result is as follows:

MIME type URLs
application/java-archive 37
application/msword 7
application/octet-stream 180
application/vnd.wordperfect 1
application/x-adobe-aco 1
application/x-msaccess 53
application/x-ms-dat 2
application/x-sega-pico-rom 1
application/x-wine-extension-ini 1
image/cis-cod 221
image/svg+xml 1
message/rfc822 4
text/html 8
text/plain 712
text/x-tcl 1
  1230

So only 221 of the 1552 candidate files could be downloaded and are actually (or at least very likely) CIS/COD images.

In which version of the file format have the images been stored? Looking at their first six bytes reveals that:

for f in image_cis-cod/*cod; do
    echo $(head --bytes=6 --quiet $f)
done | sort | uniq -c
version files
CIS2.3 13
CIS2.4 19
CIS2.5 147
CIS3.0 42
  221

So these are mainly files in CIS/COD version 2.5. With a magic file for the file command we can also extract the heights and widths of the images and plot them:

Widths and heights of CIS/COD images

So most images are smaller than 800x600 pixels and there is one large image 2000x1400 pixels in size.

Let us have a look at the hosts that hosted the images

host name (reverse notation) images
com.atyour 1
com.british-waterways 75
com.compsci 35
com.highpeaknet 31
com.infinop 10
com.infinop.euclid 3
com.intermodalex.testbox25 1
com.tyenet.w3 8
com.u-net 31
de.uni-hannover.stud 2
il.co.save-net.ingw 1
jp.or.cute 4
net.intrepid 1
nl.uva.uba.info 1
uk.co.demon.rosebank 6
uk.co.demon.sweir.mandle 1
uk.co.demon.sweir.simp 1
uk.co.demon.sweir.suddy 1
uk.co.demon.thecdp 8

Apart from three hosts related to companies that developed the CIS/COD image format (compsci.com, infinop.com, euclid.infinop.com) two British web pages have hosted a larger amount of CIS/COD images: british-waterways.com and highpeaknet.com.

Unfortunately, there is no tool (yet) for converting the images into a useable image format. So I converted the 42 images in CIS/COD version 3.0 manually with LSIC 2.6 and created the following collage:

A collage of 42 CIS/COD images found on the Web

These might be the only CIS/COD 3.0 images that are available on the Web!