svn commit: r1416781 - in /commons/proper/imaging/trunk/src/main/java/org/apache/commons/imaging/formats/png: PngConstants.java PngWriter.java

[damjan]

Author: damjan
Date: Tue Dec  4 05:10:17 2012
New Revision: 1416781

URL: http://svn.apache.org/viewvc?rev=1416781&view=rev
Log:
Add support for the PNG tRNS chunk.


Modified:
    
commons/proper/imaging/trunk/src/main/java/org/apache/commons/imaging/formats/png/PngConstants.java
    
commons/proper/imaging/trunk/src/main/java/org/apache/commons/imaging/formats/png/PngWriter.java

Modified: 
commons/proper/imaging/trunk/src/main/java/org/apache/commons/imaging/formats/png/PngConstants.java
URL: 
http://svn.apache.org/viewvc/commons/proper/imaging/trunk/src/main/java/org/apache/commons/imaging/formats/png/PngConstants.java?rev=1416781&r1=1416780&r2=1416781&view=diff
==============================================================================
--- 
commons/proper/imaging/trunk/src/main/java/org/apache/commons/imaging/formats/png/PngConstants.java
 (original)
+++ 
commons/proper/imaging/trunk/src/main/java/org/apache/commons/imaging/formats/png/PngConstants.java
 Tue Dec  4 05:10:17 2012
@@ -28,6 +28,8 @@ public interface PngConstants extends Im
             new byte[] { 73, 72, 68, 82 });
     public final static BinaryConstant PLTE_CHUNK_TYPE = new BinaryConstant(
             new byte[] { 80, 76, 84, 69 });
+    public final static BinaryConstant TRNS_CHUNK_TYPE = new BinaryConstant(
+            new byte[] { 't', 'R', 'N', 'S'});
     public final static BinaryConstant IEND_CHUNK_TYPE = new BinaryConstant(
             new byte[] { 73, 69, 78, 68 });
     public final static BinaryConstant IDAT_CHUNK_TYPE = new BinaryConstant(

Modified: 
commons/proper/imaging/trunk/src/main/java/org/apache/commons/imaging/formats/png/PngWriter.java
URL: 
http://svn.apache.org/viewvc/commons/proper/imaging/trunk/src/main/java/org/apache/commons/imaging/formats/png/PngWriter.java?rev=1416781&r1=1416780&r2=1416781&view=diff
==============================================================================
--- 
commons/proper/imaging/trunk/src/main/java/org/apache/commons/imaging/formats/png/PngWriter.java
 (original)
+++ 
commons/proper/imaging/trunk/src/main/java/org/apache/commons/imaging/formats/png/PngWriter.java
 Tue Dec  4 05:10:17 2012
@@ -251,6 +251,16 @@ public class PngWriter implements PngCon
         writeChunk(os, PLTE_CHUNK_TYPE.toByteArray(), bytes);
     }
 
+    private void writeChunkTRNS(OutputStream os, Palette palette) throws 
IOException {
+        byte[] bytes = new byte[palette.length()];
+        
+        for (int i = 0; i < bytes.length; i++) {
+            bytes[i] = (byte) (0xff & (palette.getEntry(i) >> 24));
+        }
+        
+        writeChunk(os, TRNS_CHUNK_TYPE.toByteArray(), bytes);
+    }
+
     private void writeChunkIEND(OutputStream os) throws IOException {
         writeChunk(os, IEND_CHUNK_TYPE.toByteArray(), null);
     }