diff --git a/fixtures/test_icc_prophoto.jpg b/fixtures/test_icc_prophoto.jpg
new file mode 100644
index 0000000..ebf7f02
Binary files /dev/null and b/fixtures/test_icc_prophoto.jpg differ
diff --git a/metadata_test.go b/metadata_test.go
index ceb2b2e..663ec56 100644
--- a/metadata_test.go
+++ b/metadata_test.go
@@ -39,6 +39,7 @@ func TestMetadata(t *testing.T) {
 		space       string
 	}{
 		{"test.jpg", "jpeg", 0, false, false, "srgb"},
+		{"test_icc_prophoto.jpg", "jpeg", 0, false, true, "srgb"},
 		{"test.png", "png", 0, true, false, "srgb"},
 		{"test.webp", "webp", 0, false, false, "srgb"},
 	}
diff --git a/resize.go b/resize.go
index 7b2cffc..77bfbfc 100644
--- a/resize.go
+++ b/resize.go
@@ -403,11 +403,11 @@ func imageCalculations(o *Options, inWidth, inHeight int) float64 {
 	// Fixed width, auto height
 	case o.Width > 0:
 		factor = xfactor
-		o.Height = int(math.Floor(float64(inHeight) / factor))
+		o.Height = roundFloat(float64(inHeight) / factor)
 	// Fixed height, auto width
 	case o.Height > 0:
 		factor = yfactor
-		o.Width = int(math.Floor(float64(inWidth) / factor))
+		o.Width = roundFloat(float64(inWidth) / factor)
 	// Identity transform
 	default:
 		o.Width = inWidth
@@ -418,6 +418,14 @@ func imageCalculations(o *Options, inWidth, inHeight int) float64 {
 	return factor
 }
 
+func roundFloat(f float64) int {
+	if f < 0 {
+		return int(math.Ceil(f - 0.5))
+	} else {
+		return int(math.Floor(f + 0.5))
+	}
+}
+
 func calculateCrop(inWidth, inHeight, outWidth, outHeight int, gravity Gravity) (int, int) {
 	left, top := 0, 0
 
diff --git a/resize_test.go b/resize_test.go
index 96a3a2f..aeffa67 100644
--- a/resize_test.go
+++ b/resize_test.go
@@ -1,6 +1,9 @@
 package bimg
 
 import (
+	"bytes"
+	"image"
+	"image/jpeg"
 	"io/ioutil"
 	"os"
 	"path"
@@ -112,6 +115,24 @@ func TestResizeCustomSizes(t *testing.T) {
 	}
 }
 
+func TestResizePrecision(t *testing.T) {
+	// see https://github.com/h2non/bimg/issues/99
+	img := image.NewGray16(image.Rect(0, 0, 1920, 1080))
+	input := &bytes.Buffer{}
+	jpeg.Encode(input, img, nil)
+
+	opts := Options{Width: 300}
+	newImg, err := Resize(input.Bytes(), opts)
+	if err != nil {
+		t.Fatalf("Resize(imgData, %#v) error: %#v", opts, err)
+	}
+
+	size, _ := Size(newImg)
+	if size.Width != opts.Width {
+		t.Fatalf("Invalid width: %d", size.Width)
+	}
+}
+
 func TestRotate(t *testing.T) {
 	options := Options{Width: 800, Height: 600, Rotate: 270, Crop: true}
 	buf, _ := Read("fixtures/test.jpg")
diff --git a/vips.h b/vips.h
index dfdfa0f..b5b3bb2 100644
--- a/vips.h
+++ b/vips.h
@@ -50,7 +50,7 @@ typedef struct {
 	double Background[3];
 } WatermarkOptions;
 
-static int
+static unsigned long
 has_profile_embed(VipsImage *image) {
 	return vips_image_get_typeof(image, VIPS_META_ICC_NAME);
 }
@@ -247,11 +247,21 @@ vips_webpsave_bridge(VipsImage *in, void **buf, size_t *len, int strip, int qual
 	);
 }
 
+int
+vips_is_16bit (VipsInterpretation interpretation) {
+	return interpretation == VIPS_INTERPRETATION_RGB16 || interpretation == VIPS_INTERPRETATION_GREY16;
+}
+
 int
 vips_flatten_background_brigde(VipsImage *in, VipsImage **out, double background[3]) {
+	background[0] *= 256;
+	background[1] *= 256;
+	background[2] *= 256;
+
 	VipsArrayDouble *vipsBackground = vips_array_double_new(background, 3);
 	return vips_flatten(in, out,
 		"background", vipsBackground,
+		"max_alpha", vips_is_16bit(in->Type) ? 65535.0 : 255.0,
 		NULL
 	);
 }