Added JPXDecode for RGBA images

Author: radarhere

Tests/test_file_pdf.py

@@ -8,7 +8,7 @@
 
 from PIL import Image, PdfParser, features
 
-from .helper import hopper, mark_if_feature_version
+from .helper import hopper, mark_if_feature_version, skip_unless_feature
 
 
 def helper_save_as_pdf(tmp_path, mode, **kwargs):
@@ -42,6 +42,11 @@ def test_save(tmp_path, mode):
     helper_save_as_pdf(tmp_path, mode)
 
 
+@skip_unless_feature("jpg_2000")
+def test_save_rgba(tmp_path):
+    helper_save_as_pdf(tmp_path, "RGBA")
+
+
 def test_monochrome(tmp_path):
     # Arrange
     mode = "1"

src/PIL/PdfImagePlugin.py

@@ -168,6 +168,10 @@ def _save(im, fp, filename, save_all=False):
                 filter = "DCTDecode"
                 colorspace = PdfParser.PdfName("DeviceRGB")
                 procset = "ImageC"  # color images
+            elif im.mode == "RGBA":
+                filter = "JPXDecode"
+                colorspace = PdfParser.PdfName("DeviceRGB")
+                procset = "ImageC"  # color images
             elif im.mode == "CMYK":
                 filter = "DCTDecode"
                 colorspace = PdfParser.PdfName("DeviceCMYK")
@@ -194,6 +198,8 @@ def _save(im, fp, filename, save_all=False):
                 )
             elif filter == "DCTDecode":
                 Image.SAVE["JPEG"](im, op, filename)
+            elif filter == "JPXDecode":
+                Image.SAVE["JPEG2000"](im, op, filename)
             elif filter == "FlateDecode":
                 ImageFile._save(im, op, [("zip", (0, 0) + im.size, 0, im.mode)])
             elif filter == "RunLengthDecode":