cheng/libtiff
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

new update from Scott

Browse Source
This commit is contained in:
Frank Warmerdam 2001-09-24 19:54:36 +00:00
parent 19ebdba611
commit d3daae9697
1 changed files with 28 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
libtiff/tif_ojpeg.c
View File

@ -1552,6 +1552,18 @@ OJPEGVSetField(register TIFF *tif,ttag_t tag,va_list ap)
switch (tag) switch (tag)
{ {
# ifdef COLORIMETRY_SUPPORT
/* If a "ReferenceBlackWhite" TIFF tag appears in the file explicitly, undo
any modified default definition that we might have installed below, then
install the real one.
*/
case TIFFTAG_REFERENCEBLACKWHITE : if (td->td_refblackwhite)
{
_TIFFfree(td->td_refblackwhite);
td->td_refblackwhite = 0;
};
# endif /* COLORIMETRY_SUPPORT */
default : return default : return
(*sp->vsetparent)(tif,tag,ap); (*sp->vsetparent)(tif,tag,ap);
# ifdef COLORIMETRY_SUPPORT # ifdef COLORIMETRY_SUPPORT
@ -1569,19 +1581,24 @@ OJPEGVSetField(register TIFF *tif,ttag_t tag,va_list ap)
"PhotometricInterpretation" tag should always appear before an optional "PhotometricInterpretation" tag should always appear before an optional
"ReferenceBlackWhite" tag. So, we slyly peek ahead when we discover the "ReferenceBlackWhite" tag. So, we slyly peek ahead when we discover the
desired photometry, by installing modified black and white reference desired photometry, by installing modified black and white reference
levels. We install a pointer to a statically-allocated array, which levels.
lets it be overridden without "dangling" memory references, and which
should be reasonably safe since most client applications treat this data
as "read only".
*/ */
case TIFFTAG_PHOTOMETRIC : case TIFFTAG_PHOTOMETRIC :
if ( (v32 = (*sp->vsetparent)(tif,tag,ap)) if ( (v32 = (*sp->vsetparent)(tif,tag,ap))
&& td->td_photometric == PHOTOMETRIC_YCBCR ) && td->td_photometric == PHOTOMETRIC_YCBCR
{ )
static float refbw[6]={0,255,128,255,128,255}; if (td->td_refblackwhite = _TIFFmalloc(6*sizeof(float)))
{ register long top = 1 << td->td_bitspersample;
td->td_refblackwhite = _TIFFmalloc(sizeof(float)*6); td->td_refblackwhite[0] = 0;
_TIFFmemcpy( td->td_refblackwhite, refbw, sizeof(float)*6 ); td->td_refblackwhite[1] = td->td_refblackwhite[3] =
td->td_refblackwhite[5] = top - 1;
td->td_refblackwhite[2] = td->td_refblackwhite[4] = top >> 1;
}
else
{
TIFFError(tif->tif_name,"Cannot define default reference black and white levels");
v32 = 0;
}; };
return v32; return v32;
# endif /* COLORIMETRY_SUPPORT */ # endif /* COLORIMETRY_SUPPORT */