Tile generation did not work with TJXFORM_HFLIP, because the underlying transform code was using an in-place algorithm, which modified the source coefficients after the first tile was generated. Thus, create a new option which allows TurboJPEG to turn off the in-place horizontal flip if there are multiple transforms being performed from the same set of coefficients.
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@495 632fc199-4ca6-4c93-a231-07263d6284db
diff --git a/transupp.h b/transupp.h
index 7c16c19..122d448 100644
--- a/transupp.h
+++ b/transupp.h
@@ -128,6 +128,13 @@
boolean trim; /* if TRUE, trim partial MCUs as needed */
boolean force_grayscale; /* if TRUE, convert color image to grayscale */
boolean crop; /* if TRUE, crop source image */
+ boolean slow_hflip; /* For best performance, the JXFORM_FLIP_H transform
+ normally modifies the source coefficients in place.
+ Setting this to TRUE will instead use a slower,
+ double-buffered algorithm, which leaves the source
+ coefficients in tact (necessary if other transformed
+ images must be generated from the same set of
+ coefficients. */
/* Crop parameters: application need not set these unless crop is TRUE.
* These can be filled in by jtransform_parse_crop_spec().