adjust formatting of 2, 4 bit tiff load/save

To make it libvipsey. Small fixes as well.

ChangeLog

@@ -31,6 +31,8 @@
 - deprecate heifload autorotate -- it's now always on
 - revised resize improves accuracy [kleisauke]
 - add --vips-config flag to show configuration info
+- add "bitdepth" param to tiff load and save, deprecate "squash" [MathemanFlo]
+- tiff load and save now supports 2 and 4 bit data [MathemanFlo]
 
 24/4/20 started 8.9.3
 - better iiif tile naming [IllyaMoskvin]

libvips/foreign/tiff2vips.c

@@ -199,8 +199,8 @@
  * 	- better handling of aligned reads in multipage tiffs
  * 28/5/20
  * 	- add subifd
- * 06/6/20
+ * 06/6/20 MathemanFlo
- *  - add load functionality for 2 and 4 bit greyscale tiffs
+ * 	- support 2 and 4 bit greyscale load
  */
 
 /*
@@ -1026,14 +1026,13 @@ rtiff_onebit_line( Rtiff *rtiff, VipsPel *q, VipsPel *p, int n, void *flg )
 {
 	int photometric_interpretation = 
 		rtiff->header.photometric_interpretation;
-
-	int x, i, z;
-	VipsPel bits;
-
 	int black = photometric_interpretation == PHOTOMETRIC_MINISBLACK ?
 		0 : 255;
 	int white = black ^ 0xff;
 
+	int x, i, z;
+	VipsPel bits;
+
 	/* (sigh) how many times have I written this?
 	 */
 	x = 0; 
@@ -1051,6 +1050,7 @@ rtiff_onebit_line( Rtiff *rtiff, VipsPel *q, VipsPel *p, int n, void *flg )
 	 */
 	if( n & 7 ) {
 		bits = p[i];
+
 		for( z = 0; z < (n & 7); z++ ) {
 			q[x + z] = (bits & 128) ? white : black;
 			bits <<= 1;
@@ -1063,9 +1063,11 @@ rtiff_onebit_line( Rtiff *rtiff, VipsPel *q, VipsPel *p, int n, void *flg )
 static void
 rtiff_twobit_line( Rtiff *rtiff, VipsPel *q, VipsPel *p, int n, void *flg )
 {
+	int photometric_interpretation = 
+		rtiff->header.photometric_interpretation;
+	int minisblack = photometric_interpretation == PHOTOMETRIC_MINISBLACK;
+
 	int x, i, z;
-	int minisblack = 
-		rtiff->header.photometric_interpretation == PHOTOMETRIC_MINISBLACK;
 	VipsPel twobits, fourbits, bits;
 
 	x = 0;
@@ -1073,7 +1075,8 @@ rtiff_twobit_line( Rtiff *rtiff, VipsPel *q, VipsPel *p, int n, void *flg )
 		bits = (VipsPel) minisblack ? p[i] : ~p[i];
 
 		for( z = 0; z < 4; z++ ) {
-			/* The grey shade is the value four times concatenated */
+			/* The grey shade is the value four times concatenated.
+			 */
 			twobits = bits >> 6;
 			fourbits = twobits | (twobits << 2);
 			q[x] = fourbits | (fourbits << 4);
@@ -1086,7 +1089,8 @@ rtiff_twobit_line( Rtiff *rtiff, VipsPel *q, VipsPel *p, int n, void *flg )
 	*/
 	if( n & 3 ) {
 		bits = (VipsPel) minisblack ? p[i] : ~p[i];
-		for( z = 0; z < (n & 3) ; z++ ) {
+
+		for( z = 0; z < (n & 3); z++ ) {
 			twobits = bits >> 6;
 			fourbits = twobits | (twobits << 2);
 			q[x + z] = fourbits | (fourbits << 4);
@@ -1100,18 +1104,20 @@ rtiff_twobit_line( Rtiff *rtiff, VipsPel *q, VipsPel *p, int n, void *flg )
 static void
 rtiff_fourbit_line( Rtiff *rtiff, VipsPel *q, VipsPel *p, int n, void *flg )
 {
+	int photometric_interpretation = 
+		rtiff->header.photometric_interpretation;
+	int minisblack = photometric_interpretation == PHOTOMETRIC_MINISBLACK;
+
 	int x, i, z;
-	int minisblack = 
-		rtiff->header.photometric_interpretation == PHOTOMETRIC_MINISBLACK;
 	VipsPel bits;
 
 	x = 0;
-
 	for( i = 0; i < (n >> 1); i++ ) {
 		bits = (VipsPel) minisblack ? p[i] : ~p[i];
 
 		for( z = 0; z < 2; z++ ) {
-			/* The grey shade is the value two times concatenated */
+			/* The grey shade is the value two times concatenated.
+			 */
 			q[x] = (bits & 0xF0) | (bits >> 4);
 			bits <<= 4;
 			x += 1;
@@ -1119,10 +1125,10 @@ rtiff_fourbit_line( Rtiff *rtiff, VipsPel *q, VipsPel *p, int n, void *flg )
 	}
 
 	/* Do last byte in line.
-	*/
+	 */
-	if( n & 1) {
+	if( n & 1 ) {
 		bits = (VipsPel) minisblack ? p[i] : ~p[i];
-		for( z = 0; z < (n & 1) ; z++ ) {
+		for( z = 0; z < (n & 1); z++ ) {
 			q[x + z] = (bits & 0xF0) | (bits >> 4);
 			bits <<= 4;
 		}

libvips/foreign/tiffsave.c

@@ -25,6 +25,7 @@
  * 	- add "subifd" to create pyr layers as sub-directories
  * 8/6/20
  * 	- add bitdepth support for 2 and 4 bit greyscale images
+ * 	- deprecate "squash"
  */
 
 /*
@@ -263,20 +264,6 @@ vips_foreign_save_tiff_class_init( VipsForeignSaveTiffClass *class )
 		G_STRUCT_OFFSET( VipsForeignSaveTiff, pyramid ),
 		FALSE );
 
-	VIPS_ARG_BOOL( class, "squash", 14, 
-		_( "Squash" ), 
-		_( "Squash images down to 1 bit" ),
-        VIPS_ARGUMENT_OPTIONAL_INPUT | VIPS_ARGUMENT_DEPRECATED,
-		G_STRUCT_OFFSET( VipsForeignSaveTiff, squash ),
-		FALSE );
-	
-	VIPS_ARG_INT( class, "bitdepth", 14,
-		_( "bitdepth" ),
-		_( "Change greyscale image bit depth to 1,2, 4 or 8." ),
-		VIPS_ARGUMENT_OPTIONAL_INPUT,
-		G_STRUCT_OFFSET( VipsForeignSaveTiff, bitdepth ),
-		1,8,8 );
-
 	VIPS_ARG_BOOL( class, "miniswhite", 14, 
 		_( "Miniswhite" ), 
 		_( "Use 0 for white in 1-bit images" ),
@@ -284,41 +271,41 @@ vips_foreign_save_tiff_class_init( VipsForeignSaveTiffClass *class )
 		G_STRUCT_OFFSET( VipsForeignSaveTiff, miniswhite ),
 		FALSE );
 
-	VIPS_ARG_ENUM( class, "resunit", 15, 
+	VIPS_ARG_INT( class, "bitdepth", 15,
+		_( "bitdepth" ),
+		_( "Write as a 1, 2, 4 or 8 bit image" ),
+		VIPS_ARGUMENT_OPTIONAL_INPUT,
+		G_STRUCT_OFFSET( VipsForeignSaveTiff, bitdepth ),
+		0, 8, 0 );
+
+	VIPS_ARG_ENUM( class, "resunit", 16, 
 		_( "Resolution unit" ), 
 		_( "Resolution unit" ),
 		VIPS_ARGUMENT_OPTIONAL_INPUT,
 		G_STRUCT_OFFSET( VipsForeignSaveTiff, resunit ),
 		VIPS_TYPE_FOREIGN_TIFF_RESUNIT, VIPS_FOREIGN_TIFF_RESUNIT_CM ); 
 
-	VIPS_ARG_DOUBLE( class, "xres", 16, 
+	VIPS_ARG_DOUBLE( class, "xres", 17, 
 		_( "Xres" ), 
 		_( "Horizontal resolution in pixels/mm" ),
 		VIPS_ARGUMENT_OPTIONAL_INPUT,
 		G_STRUCT_OFFSET( VipsForeignSaveTiff, xres ),
 		0.001, 1000000, 1 );
 
-	VIPS_ARG_DOUBLE( class, "yres", 17, 
+	VIPS_ARG_DOUBLE( class, "yres", 18, 
 		_( "Yres" ), 
 		_( "Vertical resolution in pixels/mm" ),
 		VIPS_ARGUMENT_OPTIONAL_INPUT,
 		G_STRUCT_OFFSET( VipsForeignSaveTiff, yres ),
 		0.001, 1000000, 1 );
 
-	VIPS_ARG_BOOL( class, "bigtiff", 18, 
+	VIPS_ARG_BOOL( class, "bigtiff", 19, 
 		_( "Bigtiff" ), 
 		_( "Write a bigtiff image" ),
 		VIPS_ARGUMENT_OPTIONAL_INPUT,
 		G_STRUCT_OFFSET( VipsForeignSaveTiff, bigtiff ),
 		FALSE );
 
-	VIPS_ARG_BOOL( class, "rgbjpeg", 20, 
-		_( "RGB JPEG" ),
-		_( "Output RGB JPEG rather than YCbCr" ),
-		VIPS_ARGUMENT_OPTIONAL_INPUT | VIPS_ARGUMENT_DEPRECATED, 
-		G_STRUCT_OFFSET( VipsForeignSaveTiff, rgbjpeg ),
-		FALSE );
-
 	VIPS_ARG_BOOL( class, "properties", 21, 
 		_( "Properties" ), 
 		_( "Write a properties document to IMAGEDESCRIPTION" ),
@@ -361,6 +348,20 @@ vips_foreign_save_tiff_class_init( VipsForeignSaveTiffClass *class )
 		G_STRUCT_OFFSET( VipsForeignSaveTiff, subifd ),
 		FALSE );
 
+	VIPS_ARG_BOOL( class, "rgbjpeg", 20, 
+		_( "RGB JPEG" ),
+		_( "Output RGB JPEG rather than YCbCr" ),
+		VIPS_ARGUMENT_OPTIONAL_INPUT | VIPS_ARGUMENT_DEPRECATED, 
+		G_STRUCT_OFFSET( VipsForeignSaveTiff, rgbjpeg ),
+		FALSE );
+
+	VIPS_ARG_BOOL( class, "squash", 14, 
+		_( "Squash" ), 
+		_( "Squash images down to 1 bit" ),
+		VIPS_ARGUMENT_OPTIONAL_INPUT | VIPS_ARGUMENT_DEPRECATED,
+		G_STRUCT_OFFSET( VipsForeignSaveTiff, squash ),
+		FALSE );
+
 }
 
 static void
@@ -403,10 +404,12 @@ vips_foreign_save_tiff_file_build( VipsObject *object )
 		build( object ) )
 		return( -1 );
 
-        /* handle the deprecated squash parameter */
+        /* Handle the deprecated squash parameter.
-        if( vips_object_argument_isset(object,"squash") ) {
+	 */
-            tiff->bitdepth = 1; /*we set that even in the case of LAB to LABQ */
+        if( vips_object_argument_isset( object, "squash" ) ) 
-        }
+		/* We set that even in the case of LAB to LABQ.
+		 */
+		tiff->bitdepth = 1;
 
 	if( vips__tiff_write( save->ready, file->filename,
 		tiff->compression, tiff->Q, tiff->predictor,
@@ -555,7 +558,6 @@ vips_foreign_save_tiff_buffer_init( VipsForeignSaveTiffBuffer *buffer )
  * * @tile_width: %gint for tile size
  * * @tile_height: %gint for tile size
  * * @pyramid: %gboolean, write an image pyramid
- * * @squash: %gboolean, squash 8-bit images down to 1 bit
  * * @bitdepth: %int, change bit depth to 1,2, or 4 bit
  * * @miniswhite: %gboolean, write 1-bit images as MINISWHITE
  * * @resunit: #VipsForeignTiffResunit for resolution unit
@@ -583,7 +585,7 @@ vips_foreign_save_tiff_buffer_init( VipsForeignSaveTiffBuffer *buffer )
  * can do. 
  *
  * XYZ images are automatically saved as libtiff LOGLUV with SGILOG compression.
- * Float LAB images are saved as float CIELAB. Set @squash to save as 8-bit 
+ * Float LAB images are saved as float CIELAB. Set @bitdepth to save as 8-bit 
  * CIELAB.
  *
  * Use @Q to set the JPEG compression factor. Default 75.
@@ -617,16 +619,7 @@ vips_foreign_save_tiff_buffer_init( VipsForeignSaveTiffBuffer *buffer )
  * tile. Use @depth to stop when the image fits in one pixel, or to only write
  * a single layer.
  *
- * Set @squash to make 8-bit uchar images write as 1-bit TIFFs. Values >128
+ * Set @bitdepth to save 8-bit uchar images as 1, 2 or 4-bit TIFFs.
- * are written as white, values <=128 as black. Normally vips will write
- * MINISBLACK TIFFs where black is a 0 bit, but if you set @miniswhite, it
- * will use 0 for a white bit. Many pre-press applications only work with
- * images which use this sense. @miniswhite only affects one-bit images, it
- * does nothing for greyscale images. Consider @bitdepth for depths 1, 2 and 4.
- *
- * Set @squash to squash 3-band float CIELAB images down to 8-bit CIELAB.
- *
- * Set @bitdepth to make 8-bit uchar images write as 1,2 or 4-bit TIFFs.
  * In case of depth 1: Values >128 are written as white, values <=128 as black.
  * Normally vips will write MINISBLACK TIFFs where black is a 0 bit, but if you
  * set @miniswhite, it will use 0 for a white bit. Many pre-press applications
@@ -639,8 +632,6 @@ vips_foreign_save_tiff_buffer_init( VipsForeignSaveTiffBuffer *buffer )
  * In case of depth 4: values < 16 are written as black, and so on for the
  * lighter shades. In case @miniswhite is set to true this behavior is inverted.
  * 
- * Set @bitdepth to 8 to squash 3-band float CIELAB images down to 8-bit CIELAB.
- *
  * Use @resunit to override the default resolution unit.  
  * The default 
  * resolution unit is taken from the header field 
@@ -704,8 +695,7 @@ vips_tiffsave( VipsImage *in, const char *filename, ... )
  * * @tile_width: %gint for tile size
  * * @tile_height: %gint for tile size
  * * @pyramid: %gboolean, write an image pyramid
- * * @squash: %gboolean, squash 8-bit images down to 1 bit
+ * * @bitdepth: %int, set write bit depth to 1, 2, 4 or 8
- * * @bitdepth: %int, change bit depth to 1,2 or 4-bit or squash float to 8 bit
  * * @miniswhite: %gboolean, write 1-bit images as MINISWHITE
  * * @resunit: #VipsForeignTiffResunit for resolution unit
  * * @xres: %gdouble horizontal resolution in pixels/mm

libvips/foreign/vips2tiff.c

@@ -195,9 +195,10 @@
  * 	- add PAGENUMBER support
  * 23/5/20
  * 	- add support for subifd pyramid layers
- * 8/6/20
+ * 06/6/20 MathemanFlo
  * 	- add bitdepth support for 2 and 4 bit greyscale images
  */
+
 /*
 
     This file is part of VIPS.
@@ -1190,30 +1191,34 @@ wtiff_new( VipsImage *input, const char *filename,
 		}
 	}
 
-	if( wtiff->bitdepth && !(wtiff->bitdepth == 1 || wtiff->bitdepth == 2 
+	/* Depth 8 is handled above.
-		|| wtiff->bitdepth == 4) ) {
-			g_warning( "%s",
-                _( "allows only bitdepth values 1,2 or 4. "
-					"-- disabling bitdepth") );
-            wtiff->bitdepth = 0;
-	}
-	
-    /* Can only have byte fractional bit depths for 8 bit mono.
-     * 3-band float should have been packed above.
 	 */
-	if( wtiff->bitdepth && !(wtiff->ready->Coding == VIPS_CODING_NONE &&
+	if( wtiff->bitdepth && 
-		wtiff->ready->BandFmt == VIPS_FORMAT_UCHAR && 
+		!(wtiff->bitdepth == 1 || 
-		wtiff->ready->Bands == 1) ) { 
+		  wtiff->bitdepth == 2 || 
+		  wtiff->bitdepth == 4) ) {
 		g_warning( "%s",
-                ( "can only set bitdepth for 1-band uchar and "
+			_( "bitdepth 1, 2 or 4 only -- disabling bitdepth") );
-                        "3-band float lab -- disabling bitdepth" ) );
+		wtiff->bitdepth = 0;
-        wtiff->bitdepth = 0;
 	}
 
-    if( wtiff->bitdepth &&
+	/* Can only have byte fractional bit depths for 8 bit mono.
+	 * 3-band float should have been packed above.
+	 */
+	if( wtiff->bitdepth && 
+		!(wtiff->ready->Coding == VIPS_CODING_NONE &&
+		  wtiff->ready->BandFmt == VIPS_FORMAT_UCHAR && 
+		  wtiff->ready->Bands == 1) ) { 
+		g_warning( "%s",
+			( "can only set bitdepth for 1-band uchar and "
+                        "3-band float lab -- disabling bitdepth" ) );
+		wtiff->bitdepth = 0;
+	}
+
+	if( wtiff->bitdepth &&
 		wtiff->compression == COMPRESSION_JPEG ) {
 		g_warning( "%s", 
-            _( "can't have 1,2 or 4-bit JPEG -- disabling JPEG" ) );
+			_( "can't have <8 bit JPEG -- disabling JPEG" ) );
 		wtiff->compression = COMPRESSION_NONE;
 	}
  
@@ -1285,14 +1290,14 @@ LabQ2LabC( VipsPel *q, VipsPel *p, int n )
 static void
 eightbit2onebit( Wtiff *wtiff, VipsPel *q, VipsPel *p, int n )
 {
-        int x;
-	VipsPel bits;
-
 	/* Invert in miniswhite mode.
 	 */
 	int white = wtiff->miniswhite ? 0 : 1;
 	int black = white ^ 1;
 
+        int x;
+	VipsPel bits;
+
 	bits = 0;
         for( x = 0; x < n; x++ ) {
 		bits <<= 1;
@@ -1318,12 +1323,12 @@ eightbit2onebit( Wtiff *wtiff, VipsPel *q, VipsPel *p, int n )
 static void
 eightbit2twobit( Wtiff *wtiff, VipsPel *q, VipsPel *p, int n )
 {
-	int x;
-	VipsPel bits;
 	VipsPel mask = wtiff->miniswhite ? 3 : 0;
 
+	int x;
+	VipsPel bits;
+
 	bits = 0;
-	
 	for( x = 0; x < n; x++ ) {
 		bits <<= 2;
 		bits |= (p[x] >> 6) ^ mask;
@@ -1335,9 +1340,9 @@ eightbit2twobit( Wtiff *wtiff, VipsPel *q, VipsPel *p, int n )
 	}
 
 	/* Any left-over bits? Need to be left-aligned.
-	*/
+	 */
 	if( (x & 0x3) != 0 )
-		*q++ = (wtiff->miniswhite ? ~bits : bits) << (8 - ((x & 0x3) << 1));
+		*q++ = bits << (8 - ((x & 0x3) << 1));
 }
 
 /* Pack 8 bit VIPS to 4 bit TIFF.
@@ -1345,26 +1350,26 @@ eightbit2twobit( Wtiff *wtiff, VipsPel *q, VipsPel *p, int n )
 static void
 eightbit2fourbit( Wtiff *wtiff, VipsPel *q, VipsPel *p, int n )
 {
-    int x;
+	VipsPel mask = wtiff->miniswhite ? 0xf : 0;
-    VipsPel bits;
+
-	VipsPel mask = wtiff->miniswhite ? 15 : 0;
+	VipsPel bits;
-    bits = 0;
+	int x;
 	
+	bits = 0;
 	for( x = 0; x < n; x++ ) {
 		bits <<= 4;
 		bits |= (p[x] >> 4) ^ mask;
 
 		if( (x & 0x1) == 0x1 ) {
-				*q++ = bits;
+			*q++ = bits;
-				bits = 0;
+			bits = 0;
 		}
 	}
 
-    /* Any left-over bits? Need to be left-aligned.
+	/* Any left-over bits? Need to be left-aligned.
-     */
+	 */
-    if( (x & 0x1) != 0 )
+	if( (x & 0x1) != 0 )
-        *q++ = ((VipsPel)(wtiff->miniswhite ? ~bits : bits)) 
+		*q++ = bits << (8 - ((x & 0x1) << 2));
-				<< (8 - ((x & 0x1) << 2));
 }
 
 /* Swap the sense of the first channel, if necessary.