Add image cropping. (#4117)

weed/images/cropping_test.go

@@ -0,0 +1,22 @@
+package images
+
+import (
+	"bytes"
+	"os"
+	"testing"
+
+	"github.com/seaweedfs/seaweedfs/weed/util"
+)
+
+func TestCropping(t *testing.T) {
+	fname := "sample1.jpg"
+
+	dat, _ := os.ReadFile(fname)
+
+	cropped, _ := Cropped(".jpg", bytes.NewReader(dat), 1072, 932, 1751, 1062)
+	buf := new(bytes.Buffer)
+	buf.ReadFrom(cropped)
+
+	util.WriteFile("cropped1.jpg", buf.Bytes(), 0644)
+
+}