Add autoOrient to composite options

Author: happycollision

lib/composite.js

@@ -110,6 +110,7 @@ const blend = {
  * @param {number} [images[].input.text.dpi=72] - the resolution (size) at which to render the text. Does not take effect if `height` is specified.
  * @param {boolean} [images[].input.text.rgba=false] - set this to true to enable RGBA output. This is useful for colour emoji rendering, or support for Pango markup features like `<span foreground="red">Red!</span>`.
  * @param {number} [images[].input.text.spacing=0] - text line height in points. Will use the font line height if none is specified.
+ * @param {Boolean} [images[].autoOrient=false] - set to true to use EXIF orientation data, if present, to orient the image.
  * @param {String} [images[].blend='over'] - how to blend this image with the image below.
  * @param {String} [images[].gravity='centre'] - gravity at which to place the overlay.
  * @param {Number} [images[].top] - the pixel offset from the top edge.
@@ -136,8 +137,11 @@ function composite (images) {
       throw is.invalidParameterError('image to composite', 'object', image);
     }
     const inputOptions = this._inputOptionsFromObject(image);
+    const descriptor = this._createInputDescriptor(image.input, inputOptions, { allowStream: false });
+    console.log('inputOptions', inputOptions);
+    console.log('descriptor', descriptor);
     const composite = {
-      input: this._createInputDescriptor(image.input, inputOptions, { allowStream: false }),
+      input: descriptor,
       blend: 'over',
       tile: false,
       left: 0,

lib/input.js

@@ -36,6 +36,7 @@ function _inputOptionsFromObject (obj) {
  */
 function _createInputDescriptor (input, inputOptions, containerOptions) {
   const inputDescriptor = {
+    autoOrient: false,
     failOn: 'warning',
     limitInputPixels: Math.pow(0x3FFF, 2),
     ignoreIcc: false,

src/common.cc

@@ -162,6 +162,8 @@ namespace sharp {
     descriptor->access = AttrAsBool(input, "sequentialRead") ? VIPS_ACCESS_SEQUENTIAL : VIPS_ACCESS_RANDOM;
     // Remove safety features and allow unlimited input
     descriptor->unlimited = AttrAsBool(input, "unlimited");
+    // Use the EXIF orientation to auto orient the image
+    descriptor->autoOrient = AttrAsBool(input, "autoOrient");
     return descriptor;
   }
 

src/common.h

@@ -37,6 +37,7 @@ namespace sharp {
   struct InputDescriptor {  // NOLINT(runtime/indentation_namespace)
     std::string name;
     std::string file;
+    bool autoOrient;
     char *buffer;
     VipsFailOn failOn;
     uint64_t limitInputPixels;
@@ -76,6 +77,7 @@ namespace sharp {
     int textAutofitDpi;
 
     InputDescriptor():
+      autoOrient(false),
       buffer(nullptr),
       failOn(VIPS_FAIL_ON_WARNING),
       limitInputPixels(0x3FFF * 0x3FFF),

src/pipeline.cc

@@ -636,6 +636,32 @@ class PipelineWorker : public Napi::AsyncWorker {
           composite->input->access = access;
           std::tie(compositeImage, compositeImageType) = sharp::OpenInput(composite->input);
           compositeImage = sharp::EnsureColourspace(compositeImage, baton->colourspacePipeline);
+
+          if (composite->input->autoOrient) {
+            // Calculate angle of rotation
+            VipsAngle compositeAutoRotation = VIPS_ANGLE_D0;
+            bool compositeAutoFlip = false;
+            bool compositeAutoFlop = false;
+
+            // Rotate and flip image according to Exif orientation
+            std::tie(compositeAutoRotation, compositeAutoFlip, compositeAutoFlop) =
+              CalculateExifRotationAndFlip(sharp::ExifOrientation(compositeImage));
+
+            compositeImage = sharp::RemoveExifOrientation(compositeImage);
+
+            if (compositeAutoRotation != VIPS_ANGLE_D0) {
+              compositeImage = compositeImage.rot(compositeAutoRotation);
+            }
+            // Mirror vertically (up-down) about the x-axis
+            if (compositeAutoFlip) {
+              compositeImage = compositeImage.flip(VIPS_DIRECTION_VERTICAL);
+            }
+            // Mirror horizontally (left-right) about the y-axis
+            if (compositeAutoFlop) {
+              compositeImage = compositeImage.flip(VIPS_DIRECTION_HORIZONTAL);
+            }
+          }
+
           // Verify within current dimensions
           if (compositeImage.width() > image.width() || compositeImage.height() > image.height()) {
             throw vips::VError("Image to composite must have same dimensions or smaller");