[commons-imaging] 02/04: [Imaging-216] Updated documentation for TIFF writer base class

[ki...@apache.org]

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kinow pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/commons-imaging.git

commit 0265f93162ec441aaeb78d497fd919296a0b490a
Author: gwlucastrig <co...@gmail.com>
AuthorDate: Sun Nov 15 13:21:45 2020 -0500

    [Imaging-216] Updated documentation for TIFF writer base class
---
 .../imaging/formats/tiff/write/TiffImageWriterBase.java        | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/main/java/org/apache/commons/imaging/formats/tiff/write/TiffImageWriterBase.java b/src/main/java/org/apache/commons/imaging/formats/tiff/write/TiffImageWriterBase.java
index ec890fd..43c8da4 100644
--- a/src/main/java/org/apache/commons/imaging/formats/tiff/write/TiffImageWriterBase.java
+++ b/src/main/java/org/apache/commons/imaging/formats/tiff/write/TiffImageWriterBase.java
@@ -330,9 +330,19 @@ public abstract class TiffImageWriterBase {
         final int width = src.getWidth();
         final int height = src.getHeight();
 
+        // If the source image has a color model that supports alpha,
+        // this module performs a call to checkForActualAlpha() to see whether
+        // the image that was supplied to the API actually contains
+        // non-opaque data in its alpha channel. It is common for applications
+        // to create a BufferedImage using TYPE_INT_ARGB, and fill the entire
+        // image with opaque pixels. In such a case, the file size of the output
+        // can be reduced by 25 percent by storing the image in an 3-byte RGB
+        // format. This approach will also make a small reduction in the runtime
+        // to read the resulting file when it is accessed by an application.
         final ColorModel cModel = src.getColorModel();
         final boolean hasAlpha = cModel.hasAlpha() && checkForActualAlpha(src);
 
+
         // 10/2020: In the case of an image with pre-multiplied alpha
         // (what the TIFF specification calls "associated alpha"), the
         // Java getRGB method adjusts the value to a non-premultiplied