sergiotarxz/libvips
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

better jpeg-in-tiff YCbCr read

Browse Source
This commit is contained in:
John Cupitt 2008-07-17 15:53:35 +00:00
parent 6f865e91e5
commit 6bad533988
3 changed files with 17 additions and 49 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
ChangeLog
View File

@ -32,6 +32,7 @@
- now tests for MagickWand before ImageMagick (thanks Adam)
- added "-rotate" option to vips2dj
- added man page for im_resize_linear
- better jpeg-in-tiff YCbCr read (thanks Ole)
25/1/08 started 7.14.0
- bump all version numbers for new stable

2
TODO
View File

@ -1,5 +1,7 @@
- wrap meta() stuff in C++, we need it in py as well
- TIFF JPEG read needs to map ycbcr->rgb somehow
- try
libsrc/convolution$ grep -l offsets *.c

63
libsrc/conversion/im_tiff2vips.c
View File

@ -101,6 +101,8 @@
* - set IM_META_RESOLUTION_UNIT
* 17/4/08
* - allow CMYKA (thanks Doron)
* 17/7/08
* - convert YCbCr to RGB on read
*/
/*
@ -401,45 +403,6 @@ parse_labs( ReadTiff *rtiff, IMAGE *out )
return( 0 );
}
/* Per-scanline process function for IM_CODING_LABQ.
*/
static void
ycbcr_line( PEL *q, PEL *p, int n, void *dummy )
{
int x;
for( x = 0; x < n; x++ ) {
q[0] = p[0];
q[1] = p[1];
q[2] = p[2];
q[3] = 0;
q += 4;
p += 3;
}
}
/* Read a YCbCr image.
*/
static int
parse_ycbcr( ReadTiff *rtiff, IMAGE *out )
{
if( !tfequals( rtiff->tiff, TIFFTAG_SAMPLESPERPIXEL, 3 ) ||
!tfequals( rtiff->tiff, TIFFTAG_BITSPERSAMPLE, 8 ) )
return( -1 );
out->Bands = 4;
out->Bbits = 8;
out->BandFmt = IM_BANDFMT_UCHAR;
out->Coding = IM_CODING_LABQ;
out->Type = IM_TYPE_LAB;
rtiff->sfn = ycbcr_line;
rtiff->client = NULL;
return( 0 );
}
/* Per-scanline process function for 1 bit images.
*/
static void
@ -707,7 +670,7 @@ parse_palette( ReadTiff *rtiff, IMAGE *out )
return( 0 );
}
/* Per-scanline process function for 8-bit RGB/RGBA/CMYK/CMYKA.
/* Per-scanline process function for 8-bit RGB/RGBA/CMYK/CMYKA/etc.
*/
static void
rgbcmyk8_line( PEL *q, PEL *p, int n, IMAGE *im )
@ -1014,14 +977,6 @@ parse_header( ReadTiff *rtiff, IMAGE *out )
break;
case PHOTOMETRIC_YCBCR:
/* Easy decision!
*/
if( parse_ycbcr( rtiff, out ) )
return( -1 );
break;
case PHOTOMETRIC_MINISWHITE:
case PHOTOMETRIC_MINISBLACK:
switch( bps ) {
@ -1078,8 +1033,18 @@ parse_header( ReadTiff *rtiff, IMAGE *out )
break;
case PHOTOMETRIC_YCBCR:
/* Sometimes JPEG in TIFF images are tagged as YCBCR. Ask
* libtiff to convert to RGB for us.
*/
TIFFSetField( rtiff->tiff,
TIFFTAG_JPEGCOLORMODE, JPEGCOLORMODE_RGB );
if( parse_rgb8( rtiff, out ) )
return( -1 );
break;
case PHOTOMETRIC_RGB:
/* Plain RGB.
/* RGB.
*/
switch( bps ) {
case 8: