Use Magick::Image::write rather than a hand-made loop; much faster.

2 files changed, 4 insertions, 12 deletions

diff --git a/ChangeLog b/ChangeLog
index c6db10402..576fa0d39 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,7 @@
 2014-06-05  Carl Hetherington  <cth@carlh.net>
 
+	* Large speed-up to multi-image source file decoding.
+
 	* Back-port changes from v2 which work out how separate
 	audio files should be resampled by looking at the video
 	files which are present at the same time.
diff --git a/src/lib/image_proxy.cc b/src/lib/image_proxy.cc
index 230bfacad..dbfd8c6d4 100644
--- a/src/lib/image_proxy.cc
+++ b/src/lib/image_proxy.cc
@@ -134,18 +134,8 @@ MagickImageProxy::image () const
 	_image.reset (new Image (PIX_FMT_RGB24, size, true));
 
 	using namespace MagickCore;
-	
-	uint8_t* p = _image->data()[0];
-	for (int y = 0; y < size.height; ++y) {
-		uint8_t* q = p;
-		for (int x = 0; x < size.width; ++x) {
-			Magick::Color c = magick_image->pixelColor (x, y);
-			*q++ = c.redQuantum() * 255 / QuantumRange;
-			*q++ = c.greenQuantum() * 255 / QuantumRange;
-			*q++ = c.blueQuantum() * 255 / QuantumRange;
-		}
-		p += _image->stride()[0];
-	}
+
+	magick_image->write (0, 0, size.width, size.height, "RGB", CharPixel, _image->data()[0]);
 
 	delete magick_image;