+ shared_ptr<Image> out (new Image (out_format, out_size, out_aligned));
+ out->make_black ();
+
+ libdcp::Size cropped_size = crop.apply (size ());
+
+ struct SwsContext* scale_context = sws_getContext (
+ cropped_size.width, cropped_size.height, pixel_format(),
+ inter_size.width, inter_size.height, out_format,
+ scaler->ffmpeg_id (), 0, 0, 0
+ );
+
+ uint8_t* scale_in_data[components()];
+ for (int c = 0; c < components(); ++c) {
+ scale_in_data[c] = data()[c] + int (rint (bytes_per_pixel(c) * crop.left)) + stride()[c] * (crop.top / line_factor(c));
+ }
+
+ Position<int> const corner ((out_size.width - inter_size.width) / 2, (out_size.height - inter_size.height) / 2);
+
+ uint8_t* scale_out_data[components()];
+ for (int c = 0; c < components(); ++c) {
+ scale_out_data[c] = out->data()[c] + int (rint (out->bytes_per_pixel(c) * corner.x)) + out->stride()[c] * corner.y;
+ }
+
+ sws_scale (
+ scale_context,
+ scale_in_data, stride(),
+ 0, cropped_size.height,
+ scale_out_data, out->stride()
+ );
+
+ sws_freeContext (scale_context);
+
+ return out;
+}
+
+shared_ptr<Image>
+Image::scale (libdcp::Size out_size, Scaler const * scaler, AVPixelFormat out_format, bool out_aligned) const
+{
+ assert (scaler);
+ /* Empirical testing suggests that sws_scale() will crash if
+ the input image is not aligned.
+ */
+ assert (aligned ());
+
+ shared_ptr<Image> scaled (new Image (out_format, out_size, out_aligned));