public void Init(int width, int height, VP8Io io,
byte[] data, int data_i, int data_size, byte[] output)
{
width_ = width;
height_ = height;
status_ = VP8StatusCode.Ok;
io_ = io;
io_.opaque = output;
io_.width = width_;
io_.height = height_;
br_.Init (data, data_i, (uint)data_size);
}
public WebPDecoder(Stream input, WebPMetaData info)
{
m_input = new ArcView.Reader (input);
m_info = info;
m_stride = (int)info.Width * 4;
m_output = new byte[m_stride * (int)info.Height];
m_io = new VP8Io();
if (0 != m_info.AlphaOffset)
{
m_input.BaseStream.Position = m_info.AlphaOffset;
m_alpha_data = m_input.ReadBytes (m_info.AlphaSize);
m_alpha_plane = new byte[info.Width * info.Height];
Format = PixelFormats.Bgra32;
}
else
{
Format = PixelFormats.Bgr32;
}
}
public bool Init(byte[] data, VP8Io src_io, byte[] output)
{
m_io = new VP8Io();
int alpha_data = HeaderLen;
int alpha_data_size = data.Length - HeaderLen;
width_ = src_io.width;
height_ = src_io.height;
if (data.Length <= HeaderLen)
return false;
method_ = (data[0] >> 0) & 3;
filter_ = (data[0] >> 2) & 3;
pre_processing_ = (data[0] >> 4) & 3;
int rsrv = (data[0] >> 6) & 3;
if (method_ < NoCompression
|| method_ > LosslessCompression
|| filter_ >= WebpFilter.Last
|| pre_processing_ > PreprocessedLevels
|| rsrv != 0)
{
return false;
}
bool ok = false;
if (NoCompression == method_)
{
int alpha_decoded_size = width_ * height_;
ok = (alpha_data_size >= alpha_decoded_size);
}
else
{
ok = DecodeAlphaHeader (data, alpha_data, alpha_data_size, output);
}
FiltersInit();
// Copy the necessary parameters from src_io to io
// m_io.Init();
m_io.opaque = output; // output plane
m_io.width = src_io.width;
m_io.height = src_io.height;
return ok;
}
