--- /dev/null
+This directory performs stress testing of "apitrace trim".
+
+For each trace file in this directory the trim_stress.py test driver
+will perform the following operations:
+
+Given <program>.trace:
+
+ 1. Generate snapshots of original trace in ./<program>-ref/
+
+ 2. For each frame of the trace:
+
+ 1. Use "apitrace trim" to trim <program>.trace to a
+ single-frame trace in <program>-trim.trace
+
+ 2. Generate a snapshot of the trimmed trace to
+ ./<program>-out/<frame>.png
+
+ 3. Use "apitrace diff-images" to compare all snapshots in
+ ./<program>-out with those in ./<program>-ref