PVRImage.cs

using System;
using System.Runtime.InteropServices;
public class PVRImage {
    public static readonly UInt32 headerVersion=0x03525650;
    private static readonly UInt32 badEndianess=0x50565203;
    private static readonly int HeaderSize=52;
    private byte[] rawData;
    private PVRHeader header;
    public PVRHeader RawHeaderData{get{return header;}}
    /// <summary>
    /// Checks to see if the header matches big or little endianness.
    /// If it matches neither, the file is not a valid PVR file or the PVR Header spec has updated.
    /// </summary>
    /// <value></value>
    public bool IsValid{
        get{
            return(header.Version==headerVersion||header.Version==badEndianess);
        }
    }
    public bool EndianMatch{
        get{return header.Version==headerVersion;}
    }
    public TextureFlags Flags{get{ return (TextureFlags)header.Flags;}}
    public PixelFormat pixelFormat{get{return (PixelFormat)header.PixelFormat;}}
    public bool isLinear{get{return header.ColorSpace==0;}}
    public ChannelType channelType{get{return (ChannelType)header.ChannelType;}}
    public int Height{get{return (int)header.Height;}}
    public int Width{get{return (int)header.Width;}}
    public int NumSurfaces{get{return (int)header.NumSurfaces;}}
    public int NumFaces{get{return (int)header.NumFaces;}}
    public int MipMapCount{get{return (int)header.MipMapCount;}}
    public int MetaDataSize{get{return (int)header.MetaDataSize;}}
    public int MetaDataOffset{get{return HeaderSize;}}
    public int TextureDataOffset{get{return MetaDataOffset+MetaDataSize;}}
    /*
    Convenience methods for getting a byte[] of specific parts of the file.
     */
    public byte[] GetMetaData(){
        byte[] metaData= new byte[MetaDataSize];
        GetMetaData(metaData);
        return metaData;
    }
    public void GetMetaData(byte[] metaData){
        System.Buffer.BlockCopy(rawData,MetaDataOffset,metaData,0,MetaDataSize);
    }
    public byte[] GetTextureData(){
        byte[] rgbData = new byte[rawData.Length-TextureDataOffset];
        GetRGBData(rgbData);
        return rgbData;
    }
    public void GetRGBData(byte[] rgbData){
        System.Buffer.BlockCopy(rawData,TextureDataOffset,rgbData,0,rgbData.Length);
    }
    private PVRImage(){}
    public PVRImage(byte[] allBytes){
        rawData=allBytes;
        header = ByteArrayToStructure<PVRHeader>(rawData);
    }

    static T ByteArrayToStructure<T>(byte[] bytes) where T : struct
    {
        var handle = GCHandle.Alloc(bytes, GCHandleType.Pinned);
        try {
            return (T) Marshal.PtrToStructure(handle.AddrOfPinnedObject(), typeof(T));
        }
        finally {
            handle.Free();
        }
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct PVRHeader{
        public UInt32 Version;
        public UInt32 Flags;
        public UInt64 PixelFormat;
        public UInt32 ColorSpace;
        public UInt32 ChannelType;
        public UInt32 Height;
        public UInt32 Width;
        public UInt32 Depth;
        public UInt32 NumSurfaces;
        public UInt32 NumFaces;
        public UInt32 MipMapCount;
        public UInt32 MetaDataSize;
    }

    public enum TextureFlags{
        No_Flag=0,
        Pre_Multiplied=0x2
    }
    public enum PixelFormat{
        PVRTC_2bpp_RGB= 0 ,
        PVRTC_2bpp_RGBA= 1 ,
        PVRTC_4bpp_RGB= 2 ,
        PVRTC_4bpp_RGBA= 3 ,
        PVRTCII_2bpp= 4 ,
        PVRTCII_4bpp= 5 ,
        ETC1= 6 ,
        DXT1= 7 ,
        DXT2= 8 ,
        DXT3= 9 ,
        DXT4= 10 ,
        DXT5= 11 ,
        BC1= 7 ,
        BC2= 9 ,
        BC3= 11 ,
        BC4= 12 ,
        BC5= 13 ,
        BC6= 14 ,
        BC7= 15 ,
        UYVY= 16 ,
        YUY2= 17 ,
        BW1bpp= 18 ,
        R9G9B9E5_Shared_Exponent= 19 ,
        RGBG8888= 20 ,
        GRGB8888= 21 ,
        ETC2_RGB= 22 ,
        ETC2_RGBA= 23 ,
        ETC2_RGB_A1= 24 ,
        EAC_R11=  25 ,
        EAC_RG11=  26 ,
        ASTC_4x4= 27 ,
        ASTC_5x4= 28 ,
        ASTC_5x5= 29 ,
        ASTC_6x5= 30 ,
        ASTC_6x6= 31 ,
        ASTC_8x5= 32 ,
        ASTC_8x6= 33 ,
        ASTC_8x8= 34 ,
        ASTC_10x5= 35 ,
        ASTC_10x6= 36 ,
        ASTC_10x8= 37 ,
        ASTC_10x10= 38 ,
        ASTC_12x10= 39 ,
        ASTC_12x12= 40 ,
        ASTC_3x3x3= 41 ,
        ASTC_4x3x3= 42 ,
        ASTC_4x4x3= 43 ,
        ASTC_4x4x4= 44 ,
        ASTC_5x4x4= 45 ,
        ASTC_5x5x4= 46 ,
        ASTC_5x5x5= 47 ,
        ASTC_6x5x5= 48 ,
        ASTC_6x6x5= 49 ,
        ASTC_6x6x6= 50,
    }

    public enum ChannelType{
        UByte_Norm=0,
        SByte_Norm=1,
        UByte=2,
        SByte=3,
        UShort_Norm=4,
        Short_Norm=5,
        UShort=6,
        Short=7,
        UInt_Norm=8,
        Int_Norm=9,
        UInt=10,
        Int=11,
        Float=12,
    }
}