diff options
Diffstat (limited to 'jpeg/jfdctflt.c')
| -rw-r--r-- | jpeg/jfdctflt.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/jpeg/jfdctflt.c b/jpeg/jfdctflt.c index 74d0d862d..013f29e0c 100644 --- a/jpeg/jfdctflt.c +++ b/jpeg/jfdctflt.c @@ -2,7 +2,7 @@ * jfdctflt.c * * Copyright (C) 1994-1996, Thomas G. Lane. - * Modified 2003-2009 by Guido Vollbeding. + * Modified 2003-2017 by Guido Vollbeding. * This file is part of the Independent JPEG Group's software. * For conditions of distribution and use, see the accompanying README file. * @@ -48,12 +48,14 @@ */ #if DCTSIZE != 8 - Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */ + Sorry, this code only copes with 8x8 DCT blocks. /* deliberate syntax err */ #endif /* * Perform the forward DCT on one block of samples. + * + * cK represents cos(K*pi/16). */ GLOBAL(void) @@ -89,7 +91,7 @@ jpeg_fdct_float (FAST_FLOAT * data, JSAMPARRAY sample_data, JDIMENSION start_col tmp11 = tmp1 + tmp2; tmp12 = tmp1 - tmp2; - /* Apply unsigned->signed conversion */ + /* Apply unsigned->signed conversion. */ dataptr[0] = tmp10 + tmp11 - 8 * CENTERJSAMPLE; /* phase 3 */ dataptr[4] = tmp10 - tmp11; |