/// <summary>
/// Attempts to load an MNG from the specified file name
/// </summary>
/// <param name="filename">Name of the MNG file to load</param>
public bool Load(string filename)
{
chunks = new List<MNGChunk>();
pngs = new List<PNG>();
offsets = new List<Point>();
// Open the file for reading
Stream stream = File.OpenRead(filename);
// Create a new header (should be 1 per file) and
// read it from the stream
MNGHeader header = new MNGHeader();
try
{
header.Read(stream);
}
catch (Exception)
{
stream.Close();
return false;
//throw;
}
MNGChunk chunk;
PNG png = null;
PLTEChunk globalPLTE = null;
// Read chunks from the stream until we reach the MEND chunk
do
{
// Read a generic Chunk
chunk = new MNGChunk();
try
{
chunk.Read(stream);
}
catch (Exception)
{
stream.Close();
return false;
//throw;
}
// Take a look at the chunk type and decide what derived class to
// use to create a specific chunk
switch (chunk.ChunkType)
{
case MHDRChunk.NAME:
if (headerChunk != null)
throw new ApplicationException(String.Format(
"Only one chunk of type {0} is allowed", chunk.ChunkType));
chunk = headerChunk = new MHDRChunk(chunk);
break;
case MENDChunk.NAME:
chunk = new MENDChunk(chunk);
break;
case TERMChunk.NAME:
chunk = new TERMChunk(chunk);
break;
case BACKChunk.NAME:
chunk = new BACKChunk(chunk);
break;
case BKGDChunk.NAME:
chunk = new BKGDChunk(chunk);
break;
case PLTEChunk.NAME:
chunk = new PLTEChunk(chunk);
// We can get an PLTE chunk w/o having gotten
// an IHDR
if (png != null)
{
png.PLTE = chunk as PLTEChunk;
if (png.PLTE.IsEmpty())
{
if (globalPLTE == null)
throw new ApplicationException(String.Format(
"An empty PLTE chunk was found inside a IHDR/IEND pair but no 'global' PLTE chunk was found"));
png.PLTE = globalPLTE;
}
}
else
globalPLTE = chunk as PLTEChunk;
break;
case DEFIChunk.NAME:
DEFIChunk dchunk = new DEFIChunk(chunk);
Point p = new Point();
p.X = (int)dchunk.XLocation;
p.Y = (int)dchunk.YLocation;
offsets.Add(p);
break;
case IHDRChunk.NAME:
chunk = new IHDRChunk(chunk);
// This is the beginning of a new embedded PNG
png = new PNG();
png.IHDR = chunk as IHDRChunk;
break;
case IDATChunk.NAME:
chunk = new IDATChunk(chunk);
// We shouldn't get an IDAT chunk if we haven't yet
// gotten an IHDR chunk
if (png == null)
throw new ArgumentNullException("png");
png.IDAT = chunk as IDATChunk;
break;
case IENDChunk.NAME:
chunk = new IENDChunk(chunk);
// We can get an IEND chunk w/o having gotten
// an IHDR
if (png != null)
{
// However, if we've gotten an IHDR chunk then
// this is the end of the embedded PNG
png.IEND = chunk as IENDChunk;
pngs.Add(png);
png = null;
}
break;
default:
break;
}
// Add the chunk to our list of chunks
chunks.Add(chunk);
}
while (chunk.ChunkType != MENDChunk.NAME);
return true;
}
/// <summary>
/// Attempts to load an MNG from the specified file name
/// </summary>
/// <param name="filename">Name of the MNG file to load</param>
public bool Load(string filename)
{
chunks = new List <MNGChunk>();
pngs = new List <PNG>();
offsets = new List <Point>();
// Open the file for reading
Stream stream = File.OpenRead(filename);
// Create a new header (should be 1 per file) and
// read it from the stream
MNGHeader header = new MNGHeader();
try
{
header.Read(stream);
}
catch (Exception)
{
stream.Close();
return(false);
//throw;
}
MNGChunk chunk;
PNG png = null;
PLTEChunk globalPLTE = null;
// Read chunks from the stream until we reach the MEND chunk
do
{
// Read a generic Chunk
chunk = new MNGChunk();
try
{
chunk.Read(stream);
}
catch (Exception)
{
stream.Close();
return(false);
//throw;
}
// Take a look at the chunk type and decide what derived class to
// use to create a specific chunk
switch (chunk.ChunkType)
{
case MHDRChunk.NAME:
if (headerChunk != null)
{
throw new ApplicationException(String.Format(
"Only one chunk of type {0} is allowed", chunk.ChunkType));
}
chunk = headerChunk = new MHDRChunk(chunk);
break;
case MENDChunk.NAME:
chunk = new MENDChunk(chunk);
break;
case TERMChunk.NAME:
chunk = new TERMChunk(chunk);
break;
case BACKChunk.NAME:
chunk = new BACKChunk(chunk);
break;
case BKGDChunk.NAME:
chunk = new BKGDChunk(chunk);
break;
case PLTEChunk.NAME:
chunk = new PLTEChunk(chunk);
// We can get an PLTE chunk w/o having gotten
// an IHDR
if (png != null)
{
png.PLTE = chunk as PLTEChunk;
if (png.PLTE.IsEmpty())
{
if (globalPLTE == null)
{
throw new ApplicationException(String.Format(
"An empty PLTE chunk was found inside a IHDR/IEND pair but no 'global' PLTE chunk was found"));
}
png.PLTE = globalPLTE;
}
}
else
{
globalPLTE = chunk as PLTEChunk;
}
break;
case DEFIChunk.NAME:
DEFIChunk dchunk = new DEFIChunk(chunk);
Point p = new Point();
p.X = (int)dchunk.XLocation;
p.Y = (int)dchunk.YLocation;
offsets.Add(p);
break;
case IHDRChunk.NAME:
chunk = new IHDRChunk(chunk);
// This is the beginning of a new embedded PNG
png = new PNG();
png.IHDR = chunk as IHDRChunk;
break;
case IDATChunk.NAME:
chunk = new IDATChunk(chunk);
// We shouldn't get an IDAT chunk if we haven't yet
// gotten an IHDR chunk
if (png == null)
{
throw new ArgumentNullException("png");
}
png.IDAT = chunk as IDATChunk;
break;
case IENDChunk.NAME:
chunk = new IENDChunk(chunk);
// We can get an IEND chunk w/o having gotten
// an IHDR
if (png != null)
{
// However, if we've gotten an IHDR chunk then
// this is the end of the embedded PNG
png.IEND = chunk as IENDChunk;
pngs.Add(png);
png = null;
}
break;
default:
break;
}
// Add the chunk to our list of chunks
chunks.Add(chunk);
}while (chunk.ChunkType != MENDChunk.NAME);
return(true);
}
