Merge d72f4bc into add4c79

lib/output.js

@@ -458,9 +458,8 @@ function png (options) {
  * @param {boolean} [options.nearLossless=false] - use near_lossless compression mode
  * @param {boolean} [options.smartSubsample=false] - use high quality chroma subsampling
  * @param {number} [options.effort=4] - CPU effort, between 0 (fastest) and 6 (slowest)
- * @param {number} [options.pageHeight] - page height for animated output
  * @param {number} [options.loop=0] - number of animation iterations, use 0 for infinite animation
- * @param {number[]} [options.delay] - list of delays between animation frames (in milliseconds)
+ * @param {number|number[]} [options.delay] - delay(s) between animation frames (in milliseconds)
  * @param {boolean} [options.force=true] - force WebP output, otherwise attempt to use input format
  * @returns {Sharp}
  * @throws {Error} Invalid options
@@ -527,20 +526,16 @@ function webp (options) {
  *     width: 128,
  *     height: 128 * pages
  *   })
- *   .gif({
- *     pageHeight: 128,
- *     dither: 0
- *   })
+ *   .gif({ dither: 0 })
  *   .toBuffer();
  *
  * @param {Object} [options] - output options
  * @param {number} [options.colours=256] - maximum number of palette entries, including transparency, between 2 and 256
  * @param {number} [options.colors=256] - alternative spelling of `options.colours`
  * @param {number} [options.effort=7] - CPU effort, between 1 (fastest) and 10 (slowest)
  * @param {number} [options.dither=1.0] - level of Floyd-Steinberg error diffusion, between 0 (least) and 1 (most)
- * @param {number} [options.pageHeight] - page height for animated output
  * @param {number} [options.loop=0] - number of animation iterations, use 0 for infinite animation
- * @param {number[]} [options.delay] - list of delays between animation frames (in milliseconds)
+ * @param {number|number[]} [options.delay] - delay(s) between animation frames (in milliseconds)
  * @param {boolean} [options.force=true] - force GIF output, otherwise attempt to use input format
  * @returns {Sharp}
  * @throws {Error} Invalid options
@@ -657,20 +652,12 @@ function jp2 (options) {
  * @private
  *
  * @param {Object} [source] - output options
- * @param {number} [source.pageHeight] - page height for animated output
  * @param {number} [source.loop=0] - number of animation iterations, use 0 for infinite animation
  * @param {number[]} [source.delay] - list of delays between animation frames (in milliseconds)
  * @param {Object} [target] - target object for valid options
  * @throws {Error} Invalid options
  */
 function trySetAnimationOptions (source, target) {
-  if (is.object(source) && is.defined(source.pageHeight)) {
-    if (is.integer(source.pageHeight) && source.pageHeight > 0) {
-      target.pageHeight = source.pageHeight;
-    } else {
-      throw is.invalidParameterError('pageHeight', 'integer larger than 0', source.pageHeight);
-    }
-  }
   if (is.object(source) && is.defined(source.loop)) {
     if (is.integer(source.loop) && is.inRange(source.loop, 0, 65535)) {
       target.loop = source.loop;
@@ -679,13 +666,16 @@ function trySetAnimationOptions (source, target) {
     }
   }
   if (is.object(source) && is.defined(source.delay)) {
-    if (
+    // We allow singular values as well
+    if (is.integer(source.delay) && is.inRange(source.delay, 0, 65535)) {
+      target.delay = [source.delay];
+    } else if (
       Array.isArray(source.delay) &&
       source.delay.every(is.integer) &&
       source.delay.every(v => is.inRange(v, 0, 65535))) {
       target.delay = source.delay;
     } else {
-      throw is.invalidParameterError('delay', 'array of integers between 0 and 65535', source.delay);
+      throw is.invalidParameterError('delay', 'integer or an array of integers between 0 and 65535', source.delay);
     }
   }
 }

src/common.cc

@@ -490,30 +490,24 @@ namespace sharp {
 
   /*
     Set animation properties if necessary.
-    Non-provided properties will be loaded from image.
   */
-  VImage SetAnimationProperties(VImage image, int pageHeight, std::vector<int> delay, int loop) {
-    bool hasDelay = delay.size() != 1 || delay.front() != -1;
+  VImage SetAnimationProperties(VImage image, int nPages, int pageHeight, std::vector<int> delay, int loop) {
+    bool hasDelay = !delay.empty();
 
-    if (pageHeight == 0 && image.get_typeof(VIPS_META_PAGE_HEIGHT) == G_TYPE_INT) {
-      pageHeight = image.get_int(VIPS_META_PAGE_HEIGHT);
-    }
-
-    if (!hasDelay && image.get_typeof("delay") == VIPS_TYPE_ARRAY_INT) {
-      delay = image.get_array_int("delay");
-      hasDelay = true;
-    }
+    // Avoid a copy if none of the animation properties are needed.
+    if (nPages == 1 && !hasDelay && loop == -1) return image;
 
-    if (loop == -1 && image.get_typeof("loop") == G_TYPE_INT) {
-      loop = image.get_int("loop");
+    if (delay.size() == 1) {
+      // We have just one delay, repeat that value for all frames.
+      delay.insert(delay.end(), nPages - 1, delay[0]);
     }
 
-    if (pageHeight == 0) return image;
-
-    // It is necessary to create the copy as otherwise, pageHeight will be ignored!
+    // Attaching metadata, need to copy the image.
     VImage copy = image.copy();
 
-    copy.set(VIPS_META_PAGE_HEIGHT, pageHeight);
+    // Only set page-height if we have more than one page, or this could
+    // accidentally turn into an animated image later.
+    if (nPages > 1) copy.set(VIPS_META_PAGE_HEIGHT, pageHeight);
     if (hasDelay) copy.set("delay", delay);
     if (loop != -1) copy.set("loop", loop);
 
@@ -556,6 +550,14 @@ namespace sharp {
     return copy;
   }
 
+  /*
+    Multi-page images can have a page height. Fetch it, and sanity check it.
+    If page-height is not set, it defaults to the image height
+  */
+  int GetPageHeight(VImage image) {
+    return vips_image_get_page_height(image.get_image());
+  }
+
   /*
     Check the proposed format supports the current dimensions.
   */
@@ -882,4 +884,74 @@ namespace sharp {
     return image;
   }
 
+  std::pair<double, double> ResolveShrink(int width, int height, int targetWidth, int targetHeight,
+    Canvas canvas, bool swap, bool withoutEnlargement) {
+    if (swap) {
+      // Swap input width and height when requested.
+      std::swap(width, height);
+    }
+
+    double hshrink = 1.0;
+    double vshrink = 1.0;
+
+    if (targetWidth > 0 && targetHeight > 0) {
+      // Fixed width and height
+      hshrink = static_cast<double>(width) / targetWidth;
+      vshrink = static_cast<double>(height) / targetHeight;
+
+      switch (canvas) {
+        case Canvas::CROP:
+        case Canvas::MIN:
+          if (hshrink < vshrink) {
+            vshrink = hshrink;
+          } else {
+            hshrink = vshrink;
+          }
+          break;
+        case Canvas::EMBED:
+        case Canvas::MAX:
+          if (hshrink > vshrink) {
+            vshrink = hshrink;
+          } else {
+            hshrink = vshrink;
+          }
+          break;
+        case Canvas::IGNORE_ASPECT:
+          if (swap) {
+            std::swap(hshrink, vshrink);
+          }
+          break;
+      }
+    } else if (targetWidth > 0) {
+      // Fixed width
+      hshrink = static_cast<double>(width) / targetWidth;
+
+      if (canvas != Canvas::IGNORE_ASPECT) {
+        // Auto height
+        vshrink = hshrink;
+      }
+    } else if (targetHeight > 0) {
+      // Fixed height
+      vshrink = static_cast<double>(height) / targetHeight;
+
+      if (canvas != Canvas::IGNORE_ASPECT) {
+        // Auto width
+        hshrink = vshrink;
+      }
+    }
+
+    // We should not enlarge (oversample) the output image,
+    // if withoutEnlargement is specified.
+    if (withoutEnlargement) {
+      hshrink = std::max(1.0, hshrink);
+      vshrink = std::max(1.0, vshrink);
+    }
+
+    // We don't want to shrink so much that we send an axis to 0
+    hshrink = std::min(hshrink, static_cast<double>(width));
+    vshrink = std::min(vshrink, static_cast<double>(height));
+
+    return std::make_pair(hshrink, vshrink);
+  }
+
 }  // namespace sharp

src/common.h

@@ -135,6 +135,14 @@ namespace sharp {
     MISSING
   };
 
+  enum class Canvas {
+      CROP,
+      EMBED,
+      MAX,
+      MIN,
+      IGNORE_ASPECT
+  };
+
   // How many tasks are in the queue?
   extern volatile int counterQueue;
 
@@ -208,9 +216,8 @@ namespace sharp {
 
   /*
     Set animation properties if necessary.
-    Non-provided properties will be loaded from image.
   */
-  VImage SetAnimationProperties(VImage image, int pageHeight, std::vector<int> delay, int loop);
+  VImage SetAnimationProperties(VImage image, int nPages, int pageHeight, std::vector<int> delay, int loop);
 
   /*
     Remove animation properties from image.
@@ -232,6 +239,12 @@ namespace sharp {
   */
   VImage SetDensity(VImage image, const double density);
 
+  /*
+    Multi-page images can have a page height. Fetch it, and sanity check it.
+    If page-height is not set, it defaults to the image height
+  */
+  int GetPageHeight(VImage image);
+
   /*
     Check the proposed format supports the current dimensions.
   */
@@ -325,6 +338,15 @@ namespace sharp {
   */
   VImage EnsureAlpha(VImage image, double const value);
 
+  /*
+    Calculate the shrink factor, taking into account auto-rotate, the canvas
+    mode, and so on. The hshrink/vshrink are the amount to shrink the input
+    image axes by in order for the output axes (ie. after rotation) to match
+    the required thumbnail width/height and canvas mode.
+  */
+  std::pair<double, double> ResolveShrink(int width, int height, int targetWidth, int targetHeight,
+    Canvas canvas, bool swap, bool withoutEnlargement);
+
 }  // namespace sharp
 
 #endif  // SRC_COMMON_H_

src/metadata.cc

@@ -180,8 +180,6 @@ class MetadataWorker : public Napi::AsyncWorker {
       }
       if (baton->pageHeight > 0) {
         info.Set("pageHeight", baton->pageHeight);
-      } else if (baton->pages > 0) {
-        info.Set("pageHeight", baton->height);
       }
       if (baton->loop >= 0) {
         info.Set("loop", baton->loop);

src/operations.cc

@@ -308,4 +308,98 @@ namespace sharp {
     return image;
   }
 
+  /*
+   * Split and crop each frame, reassemble, and update pageHeight.
+   */
+  VImage CropMultiPage(VImage image, int left, int top, int width, int height,
+                       int nPages, int *pageHeight) {
+    if (top == 0 && height == *pageHeight) {
+      // Fast path; no need to adjust the height of the multi-page image
+      return image.extract_area(left, 0, width, image.height());
+    } else {
+      std::vector<VImage> pages;
+      pages.reserve(nPages);
+
+      // Split the image into cropped frames
+      for (int i = 0; i < nPages; i++) {
+        pages.push_back(
+          image.extract_area(left, *pageHeight * i + top, width, height));
+      }
+
+      // Reassemble the frames into a tall, thin image
+      VImage assembled = VImage::arrayjoin(pages,
+        VImage::option()->set("across", 1));
+
+      // Update the page height
+      *pageHeight = height;
+
+      return assembled;
+    }
+  }
+
+  /*
+   * Split into frames, embed each frame, reassemble, and update pageHeight.
+   */
+  VImage EmbedMultiPage(VImage image, int left, int top, int width, int height,
+                        std::vector<double> background, int nPages, int *pageHeight) {
+    if (top == 0 && height == *pageHeight) {
+      // Fast path; no need to adjust the height of the multi-page image
+      return image.embed(left, 0, width, image.height(), VImage::option()
+        ->set("extend", VIPS_EXTEND_BACKGROUND)
+        ->set("background", background));
+    } else if (left == 0 && width == image.width()) {
+      // Fast path; no need to adjust the width of the multi-page image
+      std::vector<VImage> pages;
+      pages.reserve(nPages);
+
+      // Rearrange the tall image into a vertical grid
+      image = image.grid(*pageHeight, nPages, 1);
+
+      // Do the embed on the wide image
+      image = image.embed(0, top, image.width(), height, VImage::option()
+        ->set("extend", VIPS_EXTEND_BACKGROUND)
+        ->set("background", background));
+
+      // Split the wide image into frames
+      for (int i = 0; i < nPages; i++) {
+        pages.push_back(
+          image.extract_area(width * i, 0, width, height));
+      }
+
+      // Reassemble the frames into a tall, thin image
+      VImage assembled = VImage::arrayjoin(pages,
+        VImage::option()->set("across", 1));
+
+      // Update the page height
+      *pageHeight = height;
+
+      return assembled;
+    } else {
+      std::vector<VImage> pages;
+      pages.reserve(nPages);
+
+      // Split the image into frames
+      for (int i = 0; i < nPages; i++) {
+        pages.push_back(
+          image.extract_area(0, *pageHeight * i, image.width(), *pageHeight));
+      }
+
+      // Embed each frame in the target size
+      for (int i = 0; i < nPages; i++) {
+        pages[i] = pages[i].embed(left, top, width, height, VImage::option()
+          ->set("extend", VIPS_EXTEND_BACKGROUND)
+          ->set("background", background));
+      }
+
+      // Reassemble the frames into a tall, thin image
+      VImage assembled = VImage::arrayjoin(pages,
+        VImage::option()->set("across", 1));
+
+      // Update the page height
+      *pageHeight = height;
+
+      return assembled;
+    }
+  }
+
 }  // namespace sharp

src/operations.h

@@ -108,6 +108,18 @@ namespace sharp {
    */
   VImage EnsureColourspace(VImage image, VipsInterpretation colourspace);
 
+  /*
+   * Split and crop each frame, reassemble, and update pageHeight.
+   */
+  VImage CropMultiPage(VImage image, int left, int top, int width, int height,
+                       int nPages, int *pageHeight);
+
+  /*
+   * Split into frames, embed each frame, reassemble, and update pageHeight.
+   */
+  VImage EmbedMultiPage(VImage image, int left, int top, int width, int height,
+                        std::vector<double> background, int nPages, int *pageHeight);
+
 }  // namespace sharp
 
 #endif  // SRC_OPERATIONS_H_