private byte[] DecodeASTC(int blocksize)
 {
     var buff = new byte[m_Width * m_Height * 4];
     if (!TextureDecoder.DecodeASTC(image_data, m_Width, m_Height, blocksize, blocksize, buff))
     {
         return null;
     }
     return buff;
 }
 private bool DecodeASTC(byte[] image_data, byte[] buff, int blocksize)
 {
     return(TextureDecoder.DecodeASTC(image_data, m_Width, m_Height, blocksize, blocksize, buff));
 }