Add more extensive TurboJPEG regression tests
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.2.x@762 632fc199-4ca6-4c93-a231-07263d6284db
diff --git a/BUILDING.txt b/BUILDING.txt
index 730eaf7..0b3e055 100644
--- a/BUILDING.txt
+++ b/BUILDING.txt
@@ -694,3 +694,30 @@
Building a Windows installer requires the Nullsoft Install System
(http://nsis.sourceforge.net/.) makensis.exe should be in your PATH.
+
+
+*******************************************************************************
+** Regression testing
+*******************************************************************************
+
+The most common way to test libjpeg-turbo is by invoking 'make test' on
+Unix/Linux platforms or 'ctest' on Windows platforms, once the build has
+completed. This runs a series of tests to ensure that mathematical
+compatibility has been maintained between libjpeg-turbo and libjpeg v6b. This
+also invokes the TurboJPEG unit tests, which ensure that the colorspace
+extensions, YUV encoding, decompression scaling, and other features of the
+TurboJPEG C and Java APIs are working properly (and, by extension, that the
+equivalent features of the underlying libjpeg API are also working.)
+
+Invoking 'make testclean' or 'nmake testclean' (if using NMake) or building
+the 'testclean' target (if using the Visual Studio IDE) will clean up the
+output images generated by 'make test'.
+
+On Unix/Linux platforms, more extensive tests of the TurboJPEG/OSS C and Java
+wrappers can be run by invoking 'make tjtest'. These extended TurboJPEG tests
+essentially iterate through all of the available features of the TurboJPEG APIs
+that are not covered by the TurboJPEG unit tests (this includes the lossless
+transform options) and compare the images generated by each feature to images
+generated using the equivalent feature in the libjpeg API. The extended
+TurboJPEG tests are meant to test for regressions in the TurboJPEG wrappers,
+not in the underlying libjpeg-turbo library.