Only interpolate upscaled images when the interpolate flag is set in the image dictionary.

7 files changed, 20 insertions, 9 deletions

diff --git a/draw/imagedraw.c b/draw/imagedraw.c
index d2468b38..c44a3ba1 100644
--- a/draw/imagedraw.c
+++ b/draw/imagedraw.c
@@ -289,12 +289,15 @@ fz_paintimageimp(fz_pixmap *dst, fz_bbox scissor, fz_pixmap *img, fz_matrix ctm,
 
 	/* turn on interpolation for upscaled and non-rectilinear transforms */
 	dolerp = 0;
-	if (!fz_isrectilinear(ctm))
-		dolerp = 1;
-	if (sqrtf(ctm.a * ctm.a + ctm.b * ctm.b) > img->w)
-		dolerp = 1;
-	if (sqrtf(ctm.c * ctm.c + ctm.d * ctm.d) > img->h)
-		dolerp = 1;
+	if (img->interpolate)
+	{
+		if (!fz_isrectilinear(ctm))
+			dolerp = 1;
+		if (sqrtf(ctm.a * ctm.a + ctm.b * ctm.b) > img->w)
+			dolerp = 1;
+		if (sqrtf(ctm.c * ctm.c + ctm.d * ctm.d) > img->h)
+			dolerp = 1;
+	}
 
 	bbox = fz_roundrect(fz_transformrect(ctm, fz_unitrect));
 	bbox = fz_intersectbbox(bbox, scissor);
diff --git a/fitz/dev_draw.c b/fitz/dev_draw.c
index 439c4115..4d3c94f2 100644
--- a/fitz/dev_draw.c
+++ b/fitz/dev_draw.c
@@ -601,7 +601,7 @@ fz_drawfillimage(void *user, fz_pixmap *image, fz_matrix ctm, float alpha)
 #ifdef SMOOTHSCALE
 	dx = sqrtf(ctm.a * ctm.a + ctm.b * ctm.b);
 	dy = sqrtf(ctm.c * ctm.c + ctm.d * ctm.d);
-	if (dx < image->w && dy < image->h)
+	if (dx < image->w || dy < image->h)
 	{
 		scaled = fz_smoothtransformpixmap(image, &ctm, dev->dest->x, dev->dest->y, dx, dy);
 		if (scaled == nil)
@@ -649,7 +649,7 @@ fz_drawfillimagemask(void *user, fz_pixmap *image, fz_matrix ctm,
 #ifdef SMOOTHSCALE
 	dx = sqrtf(ctm.a * ctm.a + ctm.b * ctm.b);
 	dy = sqrtf(ctm.c * ctm.c + ctm.d * ctm.d);
-	if (dx < image->w && dy < image->h)
+	if (dx < image->w || dy < image->h)
 	{
 		scaled = fz_smoothtransformpixmap(image, &ctm, dev->dest->x, dev->dest->y, dx, dy);
 		if (scaled == nil)
@@ -720,7 +720,7 @@ fz_drawclipimagemask(void *user, fz_pixmap *image, fz_matrix ctm)
 #ifdef SMOOTHSCALE
 	dx = sqrtf(ctm.a * ctm.a + ctm.b * ctm.b);
 	dy = sqrtf(ctm.c * ctm.c + ctm.d * ctm.d);
-	if (dx < image->w && dy < image->h)
+	if (dx < image->w || dy < image->h)
 	{
 		scaled = fz_smoothtransformpixmap(image, &ctm, dev->dest->x, dev->dest->y, dx, dy);
 		if (scaled == nil)
diff --git a/fitz/fitz.h b/fitz/fitz.h
index 6a339303..685a75f3 100644
--- a/fitz/fitz.h
+++ b/fitz/fitz.h
@@ -611,6 +611,7 @@ struct fz_pixmap_s
 	int refs;
 	int x, y, w, h, n;
 	fz_pixmap *mask; /* explicit soft/image mask */
+	int interpolate;
 	fz_colorspace *colorspace;
 	unsigned char *samples;
 	int freesamples;
diff --git a/fitz/res_colorspace.c b/fitz/res_colorspace.c
index f3ea317d..09e6c349 100644
--- a/fitz/res_colorspace.c
+++ b/fitz/res_colorspace.c
@@ -497,6 +497,10 @@ fz_convertpixmap(fz_pixmap *sp, fz_pixmap *dp)
 
 	assert(ss && ds);
 
+	if (sp->mask)
+		dp->mask = fz_keeppixmap(sp->mask);
+	dp->interpolate = sp->interpolate;
+
 	if (ss == fz_devicegray)
 	{
 		if (ds == fz_devicergb) fastgraytorgb(sp, dp);
diff --git a/fitz/res_pixmap.c b/fitz/res_pixmap.c
index 88e10230..e70d084d 100644
--- a/fitz/res_pixmap.c
+++ b/fitz/res_pixmap.c
@@ -12,6 +12,7 @@ fz_newpixmapwithdata(fz_colorspace *colorspace, int x, int y, int w, int h, unsi
 	pix->w = w;
 	pix->h = h;
 	pix->mask = nil;
+	pix->interpolate = 1;
 	pix->colorspace = nil;
 	pix->n = 1;
 
diff --git a/mupdf/pdf_colorspace.c b/mupdf/pdf_colorspace.c
index 4fb0c54d..28774fe1 100644
--- a/mupdf/pdf_colorspace.c
+++ b/mupdf/pdf_colorspace.c
@@ -229,6 +229,7 @@ pdf_expandindexedpixmap(fz_pixmap *src)
 
 	if (src->mask)
 		dst->mask = fz_keeppixmap(src->mask);
+	dst->interpolate = src->interpolate;
 
 	return dst;
 }
diff --git a/mupdf/pdf_image.c b/mupdf/pdf_image.c
index 9d59d9b2..aa9df25b 100644
--- a/mupdf/pdf_image.c
+++ b/mupdf/pdf_image.c
@@ -233,6 +233,7 @@ pdf_loadimageimp(fz_pixmap **imgp, pdf_xref *xref, fz_obj *rdb, fz_obj *dict, fz
 		fz_dropcolorspace(colorspace);
 
 	tile->mask = mask;
+	tile->interpolate = interpolate;
 
 	fz_free(samples);