问读取Photoshop (PSD)文件的RLE压缩层

EN

////////////////////////////////////////////////////////////////////
// Compute RLE Data Size
////////////////////////////////////////////////////////////////////
protected function _computeRLESize( data_ : ByteArray, record_ : PSDLayerRecord ) : int
{
    var numScanlines : int;
    var ii : int;
    var size : int;
    var totalSize : int;
    var pad : int;

    // Compute our total time
    totalSize = ( record_.bottom - record_.top ) * ( record_.right - record_.left );

    // Find our number of scanlines
    numScanlines = record_.bottom - record_.top;

    // Initialize our size
    size = 0;

    // Loop through each line to see how many bytes we have
    trace( "Num Scanlines: " + numScanlines );
    for ( ii = 0; ii < numScanlines; ii++ )
    {
        pad = data_.readShort();
        if ( pad % 2 != 0 ) pad++;
        size += pad;
    }

    // Output our compression
    trace( "Image is at " + size + " / " + totalSize + " compression" );

    // When we're done, back up to the beginning so we can read it
    data_.position -= numScanlines * 2;

    // Return our size
    return size + numScanlines * 2;
}