Introduction

out/tools/skdiff is an executable that takes two directories (one containing reference images, the second containing a new set of images) and writes into a third directory:

1. a difference image for each pair of non-matching images
2. an index.html page with all non-matching images

Details

skdiff by default sorts the images in index.html by the percent of pixels different. It can take a number of additional parameters:

• -threshold N: ignore all differences of intensity <= N
• -sortbymismatch: sort index.html by intensity mismatch averaged over all differing pixels
• -sortbymaxmismatch: sort index.html by the maximum intensity mismatch in the entire image

Examples

Compare linux floating point and fixed point baselines to see cross-math-library differences:

# build the skdiff tool, among other things
cd trunk
make tools

# run skdiff to compare base-linux and base-linux-fixed images
mkdir out/diff
out/Debug/skdiff gm/base-linux gm/base-linux-fixed out/diff

# view the results
chromium out/diff/index.html