Vips - Adding new operations

src/main/java/org/jlibvips/VipsImage.java

@@ -6,6 +6,8 @@
 import com.sun.jna.Pointer;
 
 import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.List;
 
 /**
  * An image, residing in memory or disk, managed by libvips. Instance methods provide transformations and queries on
@@ -55,6 +57,27 @@ public static VipsImage fromPdf(Path p, int page) {
         return image;
     }
 
+    public static List<VipsImage> getPagesFromPdf(Path p, int MAX_PAGES){
+        List<VipsImage> pages = new ArrayList<>();
+        try {
+            VipsImage first = fromPdf(p, 0);
+            pages.add(first);
+
+            for (int i = 1; i < Math.min(first.getPages(), MAX_PAGES); i++) {
+                VipsImage page = fromPdf(p, i);
+                pages.add(page);
+            }
+        }
+        catch (Exception exception) {
+            throw new CouldNotLoadPdfVipsException(-1);
+        }
+        return pages;
+    }
+
+    public static int init(){
+        return VipsBindings.INSTANCE.vips_init("application");
+    }
+
     /**
      * Loads a PDF document's page as {@link VipsImage} in the greatest possible resolution.
      *
@@ -189,6 +212,10 @@ public int getWidth() {
         return VipsBindings.INSTANCE.vips_image_get_width(ptr);
     }
 
+    public int getPages() {
+        return VipsBindings.INSTANCE.vips_image_get_n_pages(ptr);
+    }
+
     /**
      * Get the height of this image.
      *
@@ -209,6 +236,11 @@ public int getBands() {
         return VipsBindings.INSTANCE.vips_image_get_bands(ptr);
     }
 
+    public VipsImage getGrids() {
+        var out = new Pointer[getPages()];
+        VipsBindings.INSTANCE.vips_grid(this.ptr, out, getHeight()/getPages(), getPages(), 1, null);
+        return new VipsImage(out[0]);
+    }
     /**
      * Insert sub into main at position.
      *

src/main/java/org/jlibvips/jna/VipsBindings.java

@@ -8,23 +8,31 @@ public interface VipsBindings extends Library {
 
     VipsBindings INSTANCE = Native.load("libvips.42.dylib", VipsBindings.class);
 
+    int vips_init(String argv0);
+
     Pointer vips_image_new_from_file(String fileName, Object...args);
 
     int vips_pdfload(String fileName, Pointer[] pointer, Object...args);
 
     int vips_image_get_width(Pointer pointer);
     int vips_image_get_height(Pointer pointer);
+    int vips_image_get_n_pages(Pointer pointer);
 
     int vips_image_get_bands(Pointer pointer);
 
+    int vips_grid(Pointer in, Pointer[] out, int tile_height, int across, int down, Object...args);
+
     int vips_dzsave(Pointer pointer, String outDir, Object...args);
 
     int vips_thumbnail_image(Pointer in, Pointer[] out, int width, Object...args);
 
+    int vips_extract_area(Pointer in, Pointer[] out, int left, int top, int width, int height, Object...args);
+
     Pointer vips_array_double_new(double[] array, int n);
 
     int vips_vipssave(Pointer in, String filename, Object...args);
     int vips_jpegsave(Pointer in, String filename, Object...args);
+    int vips_pngsave(Pointer in, String filename, Object...args);
     int vips_webpsave(Pointer in, String filename, Object...args);
 
     int vips_insert(Pointer main, Pointer sub, Pointer[] out, int x, int y, Object...args);

src/main/java/org/jlibvips/operations/JpegSaveOperation.java

@@ -9,6 +9,8 @@
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.attribute.FileAttribute;
 
 public class JpegSaveOperation implements SaveOperation {
 
@@ -45,6 +47,23 @@ public Path save() throws IOException, VipsException {
         return path;
     }
 
+    public Path saveAsPng(String pathStr) throws IOException, VipsException {
+        Path path = Files.createFile(Paths.get(pathStr).toAbsolutePath());
+        int ret = VipsBindings.INSTANCE.vips_pngsave(image.getPtr(), path.toString(),
+                new Varargs().add("Q", quality)
+                        .add("optimize_coding", VipsUtils.booleanToInteger(optimizeCoding))
+                        .add("interlace", VipsUtils.booleanToInteger(interlace))
+                        .add("strip", VipsUtils.booleanToInteger(strip))
+                        .add("no_subsample", VipsUtils.booleanToInteger(noSubsample))
+                        .add("trellis_quant", VipsUtils.booleanToInteger(trellisQuant))
+                        .add("overshoot_deringing", VipsUtils.booleanToInteger(overshootDeringing))
+                        .add("optimize_scans", optimizeScans).toArray());
+        if(ret != 0) {
+            throw new VipsException("vips_pngsave", ret);
+        }
+        return path;
+    }
+
     /**
      * Set the quality factor.
      *