import fixes

ChangeLog

@@ -15,6 +15,9 @@
 - added postclose callbacks
 - added vipsthumbnail 
 - oops, generate C++/Python wrappers for deprecated operations by default
+- read TIFF images strip-wise, not scanline-wise
+- better TIFF YCbCr reading (thanks Ole)
+- isanalyze generates fewer silly error messages
 
 26/11/09 started 7.20.3
 - updated en_GB.po translation 

libvips/format/im_analyze2vips.c

@@ -6,6 +6,8 @@
  * 	- better byteswapper
  * 12/5/09
  *	- fix signed/unsigned warning
+ * 13/1/09
+ * 	- try harder not to generate error messages in "isanalyze"
  */
 
 /*
@@ -309,6 +311,8 @@ read_header( const char *header )
 		return( NULL );
 	if( len != sizeof( struct dsr ) ) {
 		im_free( d );
+		im_error( "im_analyze2vips", 
+			"%s", _( "header file size incorrect" ) );
 		return( NULL );
 	}
 
@@ -493,6 +497,8 @@ isanalyze( const char *filename )
 	int fmt;
 
 	generate_filenames( filename, header, image );
+	if( !im_existsf( "%s", header ) )
+		return( 0 );
 	if( !(d = read_header( header )) )
 		return( 0 );
 
@@ -520,11 +526,8 @@ analyze2vips_header( const char *filename, IMAGE *out )
 	int fmt;
 
 	generate_filenames( filename, header, image );
-	if( !(d = read_header( header )) ) {
+	if( !(d = read_header( header )) ) 
-		im_error( "im_analyze2vips", 
-			"%s", _( "header file size incorrect" ) );
 		return( -1 );
-	}
 
 #ifdef DEBUG
 	print_dsr( d );
@@ -560,11 +563,8 @@ im_analyze2vips( const char *filename, IMAGE *out )
 		IM_ARCH_NATIVE : IM_ARCH_BYTE_SWAPPED;
 
 	generate_filenames( filename, header, image );
-	if( !(d = read_header( header )) ) {
+	if( !(d = read_header( header )) ) 
-		im_error( "im_analyze2vips", 
-			"%s", _( "header file size incorrect" ) );
 		return( -1 );
-	}
 
 #ifdef DEBUG
 	print_dsr( d );

libvips/format/im_tiff2vips.c

@@ -101,11 +101,16 @@
  * 	- set IM_META_RESOLUTION_UNIT
  * 17/4/08
  * 	- allow CMYKA (thanks Doron)
+ * 17/7/08
+ * 	- convert YCbCr to RGB on read
  * 15/8/08
  * 	- reorganise for image format system
  * 20/12/08
  * 	- dont read with mmap: no performance advantage with libtiff, chews up 
  * 	  VM wastefully
+ * 13/1/09
+ * 	- read strip-wise, not scanline-wise ... works with more compression /
+ * 	  subsampling schemes (esp. subsamples YCbCr), and it's a bit quicker
  */
 
 /*
@@ -393,44 +398,6 @@ 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->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
@@ -693,7 +660,7 @@ 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 )
@@ -999,14 +966,6 @@ 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 ) {
@@ -1063,9 +1022,17 @@ parse_header( ReadTiff *rtiff, IMAGE *out )
 
 		break;
 
-	case PHOTOMETRIC_RGB:
+	case PHOTOMETRIC_YCBCR:
-		/* Plain RGB.
+		/* 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:
 		switch( bps ) {
 		case 8:
 			if( parse_rgb8( rtiff, out ) )
@@ -1277,21 +1244,45 @@ read_tilewise( ReadTiff *rtiff, IMAGE *out )
 	return( 0 );
 }
 
-/* Scanline-type TIFF reader core - pass in a per-scanline transform.
+/* Stripwise reading - not all codecs work well with scanline reading,
+ * sometimes we have to read in whole strips.
  */
 static int
-read_scanlinewise( ReadTiff *rtiff, IMAGE *out )
+read_stripwise( ReadTiff *rtiff, IMAGE *out )
 {
+	int rows_per_strip;
+	tsize_t scanline_size;
+	tsize_t strip_size;
+	int number_of_strips;
+
 	PEL *vbuf;
 	tdata_t tbuf;
+	tstrip_t strip;
+	tsize_t length;
 	int y;
+	int i;
+	PEL *p;
 
 	if( parse_header( rtiff, out ) )
 		return( -1 );
 
+	if( !tfget32( rtiff->tiff, TIFFTAG_ROWSPERSTRIP, &rows_per_strip ) )
+		return( -1 );
+	scanline_size = TIFFScanlineSize( rtiff->tiff );
+	strip_size = TIFFStripSize( rtiff->tiff );
+	number_of_strips = TIFFNumberOfStrips( rtiff->tiff );
+
+#ifdef DEBUG
+	printf( "read_stripwise: rows_per_strip = %d\n", rows_per_strip );
+	printf( "read_stripwise: scanline_size = %d\n", scanline_size );
+	printf( "read_stripwise: strip_size = %d\n", strip_size );
+	printf( "read_stripwise: number_of_strips = %d\n", number_of_strips );
+#endif /*DEBUG*/
+
 	/* Make sure we can write WIO-style.
 	 */
-	if( im_outcheck( out ) || im_setupout( out ) )
+	if( im_outcheck( out ) || 
+		im_setupout( out ) )
 		return( -1 );
 
 	/* Make VIPS output buffer.
@@ -1299,24 +1290,29 @@ read_scanlinewise( ReadTiff *rtiff, IMAGE *out )
 	if( !(vbuf = IM_ARRAY( out, IM_IMAGE_SIZEOF_LINE( out ), PEL )) )
 		return( -1 );
 
-	/* Make TIFF line input buffer.
+	/* Make TIFF input buffer.
 	 */
-	if( !(tbuf = im_malloc( out, TIFFScanlineSize( rtiff->tiff ) )) ) 
+	if( !(tbuf = im_malloc( out, strip_size )) ) 
 		return( -1 );
 
-	for( y = 0; y < out->Ysize; y++ ) {
+	for( strip = 0, y = 0; strip < number_of_strips; 
-		/* Read TIFF scanline.
+		strip++, y += rows_per_strip ) {
-		 */
+		length = TIFFReadEncodedStrip( rtiff->tiff, 
-		if( TIFFReadScanline( rtiff->tiff, tbuf, y, 0 ) < 0 ) {
+			strip, tbuf, (tsize_t) -1 );
+		if( length == -1 ) {
 			im_error( "im_tiff2vips", "%s", _( "read error" ) );
 			return( -1 );
 		}
 
-		/* Process and save as VIPS.
+		for( p = tbuf, i = 0; 
-		 */
+			i < rows_per_strip && i + y < out->Ysize; 
-		rtiff->sfn( vbuf, tbuf, out->Xsize, rtiff->client );
+			i++, p += scanline_size ) {
-		if( im_writeline( y, out, vbuf ) ) 
+			/* Process and save as VIPS.
-			return( -1 );
+			 */
+			rtiff->sfn( vbuf, p, out->Xsize, rtiff->client );
+			if( im_writeline( y, out, vbuf ) ) 
+				return( -1 );
+		}
 	}
 
 	return( 0 );
@@ -1456,7 +1452,7 @@ im_tiff2vips( const char *filename, IMAGE *out )
 			return( -1 );
 	}
 	else {
-		if( read_scanlinewise( rtiff, out ) )
+		if( read_stripwise( rtiff, out ) )
 			return( -1 );
 	}
 

tools/iofuncs/vipsthumbnail.c

@@ -1,6 +1,9 @@
 /* VIPS thumbnailer
  *
  * J. Cupitt, 11/1/09
+ *
+ * 13/1/09
+ * 	- don't shrink images that are already tiny
  */
 
 #ifdef HAVE_CONFIG_H
@@ -100,9 +103,14 @@ calculate_shrink( int width, int height, double *residual )
 
 	double factor = dimension / (double) thumbnail_size;
 
+	/* If the shrink factor is <=1.0, we need to zoom rather than shrink.
+	 * Just set the factor to 1 in this case.
+	 */
+	double factor2 = factor <= 1.0 ? 1.0 : factor;
+
 	/* Int component of shrink.
 	 */
-	int shrink = floor( factor );
+	int shrink = floor( factor2 );
 
 	/* Size after int shrink.
 	 */
@@ -244,9 +252,16 @@ thumbnail( const char *filename )
 {
 	VipsFormatClass *format;
 
+	if( verbose )
+		printf( "thumbnailing %s\n", filename );
+
 	if( !(format = vips_format_for_file( filename )) )
 		return( -1 );
 
+	if( verbose )
+		printf( "detected format as %s\n", 
+			VIPS_OBJECT_CLASS( format )->nickname );
+
 	if( strcmp( VIPS_OBJECT_CLASS( format )->nickname, "jpeg" ) == 0 ) {
 		IMAGE *im;
 		int shrink;