CopyChunksFirst() public method

public CopyChunksFirst ( PngReader reader, int copy_mask ) : void
reader PngReader
copy_mask int
return void
PngWriter Class Documentation
Example #1
0
        private void btnSave_Click( object sender, RoutedEventArgs e )
        {
            CommonSaveFileDialog saveDialog = new CommonSaveFileDialog();
              saveDialog.ShowPlacesList = true;
              saveDialog.AddToMostRecentlyUsedList = true;
              saveDialog.Filters.Add( new CommonFileDialogFilter( "PNG images", "*.png" ) );
              saveDialog.DefaultFileName = DateTime.Now.ToString( "yyyyMMddhhmmss" ) + ".png";
              if ( saveDialog.ShowDialog( this ) == CommonFileDialogResult.Ok ) {
            using ( FileStream newFileStream = new FileStream( saveDialog.FileName, FileMode.OpenOrCreate, FileAccess.ReadWrite ),
              oldFileStream = new FileStream( soureFilePath, FileMode.Open, FileAccess.Read ) ) {
            string semanticInfo = @"
            sky: blue sky.
            heart: cloud heart.
            Meaning: It means love|爱|❤.
                ";

              ////// Reference: http://code.google.com/p/pngcs/wiki/Overview

              // get decoder
              pngReader = new PngReader( oldFileStream );
              // create encoder
              pngWriter = new PngWriter( newFileStream, pngReader.ImgInfo );
              // copy
              int chunkBehav = Hjg.Pngcs.Chunks.ChunkCopyBehaviour.COPY_ALL; // tell to copy all 'safe' chunks
              pngWriter.CopyChunksFirst( pngReader, chunkBehav );          // copy some metadata from reader
              int channels = pngReader.ImgInfo.Channels;
              if ( channels < 3 )
            throw new Exception( "This example works only with RGB/RGBA images" );
              for ( int row = 0; row < pngReader.ImgInfo.Rows; row++ ) {
            ImageLine l1 = pngReader.ReadRow( row ); // format: RGBRGB... or RGBARGBA...
            pngWriter.WriteRow( l1, row );
              }
              pngWriter.CopyChunksLast( pngReader, chunkBehav ); // metadata after the image pixels? can happen

              // app info
              pngWriter.GetMetadata().SetText( Hjg.Pngcs.Chunks.PngChunkTextVar.KEY_Software, "Semantic Image" );
              // semantic info
              Hjg.Pngcs.Chunks.PngChunk chunk = pngWriter.GetMetadata().SetText( Key_SemanticInfo, semanticInfo, false, false );
              chunk.Priority = true;

              pngWriter.End(); // dont forget this
              pngReader.End();

              oldFileStream.Close();
              newFileStream.Close();
            }
              }
        }