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support greyscale tiff with alpha

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thanks Robert for pointing out this omission
This commit is contained in:
John Cupitt 2013-09-16 15:25:02 +01:00
parent 2088e3d111
commit 8ccb5bbe6d
3 changed files with 83 additions and 47 deletions
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1
ChangeLog
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@ -13,6 +13,7 @@
- vipsthumbnail uses embedded jpg thumbnails if it can
- rename vips_diag() as vips_info(), add --vips-info flag
- deprecate im_hsp()
- support alpha for 8, 16 and 32-bit greyscale tiff images, thanks Robert
3/7/13 started 7.34.2
- lower priority for Matlab load to reduce segvs from Mat_Open(), thanks

11
TODO
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@ -8,19 +8,8 @@
- support planar config in tiff reader
- support GA (greyscale with alpha) in tiff reader
$ vips extract_band shark.jpg x.tif 0 -n 2
$ header x.tif
header: tiff2vips: required field 277 = 2, not 1
- is vips_hist_local() correct? it seems to leave white dots everywhere
- use VipsInterpolate to generate intermediate values in buildlut etc.
need to pull out columns of input matrix into separate image and expand each
one
- use g_log() instead of vips_info()
- do we always call copy_fields and demand_hint with ALL input images? what

118
libvips/foreign/tiff2vips.c
View File

@ -135,6 +135,8 @@
* - clip rows_per_strip down to image height to avoid overflows for huge
* values (thanks Nicolas)
* - better error msg for not PLANARCONFIG_CONTIG images
* 16/9/13
* - support alpha for 8, 16 and 32-bit greyscale images, thanks Robert
*/
/*
@ -224,6 +226,10 @@ typedef struct {
tsize_t scanline_size;
tsize_t strip_size;
int number_of_strips;
/* EOR greyscale images with this on read.
*/
int mask;
} ReadTiff;
/* Handle TIFF errors here. Shared with vips2tiff.c. These can be called from
@ -464,17 +470,26 @@ parse_onebit( ReadTiff *rtiff, int pm, VipsImage *out )
/* Per-scanline process function for 8-bit greyscale images.
*/
static void
greyscale8_line( VipsPel *q, VipsPel *p, int n, void *flg )
greyscale8_line( VipsPel *q, VipsPel *p, int n, void *client )
{
/* Extract swap mask.
*/
VipsPel mask = *((VipsPel *) flg);
ReadTiff *rtiff = (ReadTiff *) client;
int bands = rtiff->out->Bands;
int x;
/* Read bytes, swapping sense if necessary.
*/
for( x = 0; x < n; x++ )
q[x] = p[x] ^ mask;
for( x = 0; x < n; x++ ) {
q[0] = p[0] ^ rtiff->mask;
/* Process alpha, if any. Don't swap this.
*/
if( bands == 2 )
q[1] = p[1];
q += bands;
p += bands;
}
}
/* Read a 8-bit grey-scale TIFF image.
@ -482,25 +497,31 @@ greyscale8_line( VipsPel *q, VipsPel *p, int n, void *flg )
static int
parse_greyscale8( ReadTiff *rtiff, int pm, VipsImage *out )
{
VipsPel *mask;
int bands;
if( !tfequals( rtiff->tiff, TIFFTAG_SAMPLESPERPIXEL, 1 ) ||
!tfequals( rtiff->tiff, TIFFTAG_BITSPERSAMPLE, 8 ) )
/* Can have an extra alpha band.
*/
if( !tfequals( rtiff->tiff, TIFFTAG_BITSPERSAMPLE, 8 ) ||
!tfget16( rtiff->tiff, TIFFTAG_SAMPLESPERPIXEL, &bands ) )
return( -1 );
if( bands != 1 &&
bands != 2 ) {
vips_error( "tiff2vips",
"%s", _( "1 or 2 bands greyscale TIFF only" ) );
return( -1 );
}
/* Eor each pel with this later.
*/
if( !(mask = VIPS_ARRAY( out, 1, VipsPel )) )
return( -1 );
*mask = (pm == PHOTOMETRIC_MINISBLACK) ? 0 : 255;
rtiff->mask = (pm == PHOTOMETRIC_MINISBLACK) ? 0 : -1;
out->Bands = 1;
out->Bands = bands;
out->BandFmt = VIPS_FORMAT_UCHAR;
out->Coding = VIPS_CODING_NONE;
out->Type = VIPS_INTERPRETATION_B_W;
rtiff->sfn = greyscale8_line;
rtiff->client = mask;
rtiff->client = rtiff;
return( 0 );
}
@ -508,19 +529,30 @@ parse_greyscale8( ReadTiff *rtiff, int pm, VipsImage *out )
/* Per-scanline process function for 16-bit greyscale images.
*/
static void
greyscale16_line( VipsPel *q, VipsPel *p, int n, void *flg )
greyscale16_line( VipsPel *q, VipsPel *p, int n, void *client )
{
/* Extract swap mask.
*/
unsigned short mask = *((unsigned short *) flg);
unsigned short *p1 = (unsigned short *) p;
unsigned short *q1 = (unsigned short *) q;
ReadTiff *rtiff = (ReadTiff *) client;
int bands = rtiff->out->Bands;
unsigned short *p1;
unsigned short *q1;
int x;
/* Read bytes, swapping sense if necessary.
*/
for( x = 0; x < n; x++ )
q1[x] = p1[x] ^ mask;
p1 = (unsigned short *) p;
q1 = (unsigned short *) q;
for( x = 0; x < n; x++ ) {
q1[0] = p1[0] ^ rtiff->mask;
/* Process alpha, if any. Don't swap this.
*/
if( bands == 2 )
q1[1] = p1[1];
q1 += bands;
p1 += bands;
}
}
/* Read a 16-bit grey-scale TIFF image.
@ -528,25 +560,29 @@ greyscale16_line( VipsPel *q, VipsPel *p, int n, void *flg )
static int
parse_greyscale16( ReadTiff *rtiff, int pm, VipsImage *out )
{
unsigned short *mask;
int bands;
if( !tfequals( rtiff->tiff, TIFFTAG_SAMPLESPERPIXEL, 1 ) ||
!tfequals( rtiff->tiff, TIFFTAG_BITSPERSAMPLE, 16 ) )
return( -1 );
/* Eor each pel with this later.
/* Can have an extra alpha band.
*/
if( !(mask = VIPS_ARRAY( out, 1, unsigned short )) )
if( !tfequals( rtiff->tiff, TIFFTAG_BITSPERSAMPLE, 16 ) ||
!tfget16( rtiff->tiff, TIFFTAG_SAMPLESPERPIXEL, &bands ) )
return( -1 );
mask[0] = (pm == PHOTOMETRIC_MINISBLACK) ? 0 : 65535;
if( bands != 1 &&
bands != 2 ) {
vips_error( "tiff2vips",
"%s", _( "1 or 2 bands greyscale TIFF only" ) );
return( -1 );
}
out->Bands = 1;
rtiff->mask = (pm == PHOTOMETRIC_MINISBLACK) ? 0 : -1;
out->Bands = bands;
out->BandFmt = VIPS_FORMAT_USHORT;
out->Coding = VIPS_CODING_NONE;
out->Type = VIPS_INTERPRETATION_GREY16;
rtiff->sfn = greyscale16_line;
rtiff->client = mask;
rtiff->client = rtiff;
return( 0 );
}
@ -568,11 +604,21 @@ memcpy_line( VipsPel *q, VipsPel *p, int n, void *client )
static int
parse_greyscale32f( ReadTiff *rtiff, int pm, VipsImage *out )
{
if( !tfequals( rtiff->tiff, TIFFTAG_SAMPLESPERPIXEL, 1 ) ||
!tfequals( rtiff->tiff, TIFFTAG_BITSPERSAMPLE, 32 ) )
return( -1 );
int bands;
out->Bands = 1;
/* Can have an extra alpha band.
*/
if( !tfequals( rtiff->tiff, TIFFTAG_BITSPERSAMPLE, 32 ) ||
!tfget16( rtiff->tiff, TIFFTAG_SAMPLESPERPIXEL, &bands ) )
return( -1 );
if( bands != 1 &&
bands != 2 ) {
vips_error( "tiff2vips",
"%s", _( "1 or 2 bands greyscale TIFF only" ) );
return( -1 );
}
out->Bands = bands;
out->BandFmt = VIPS_FORMAT_FLOAT;
out->Coding = VIPS_CODING_NONE;
out->Type = VIPS_INTERPRETATION_B_W;