imftiledoutputfile.cpp

对gif

        // Create a new BufferedTile, copy the pixelData into it, and
        // insert it into the tileMap.
        //

	ofd->tileMap[currentTile] =
	    new BufferedTile ((const char *)pixelData, pixelDataSize);
    }
}


void
convertToXdr (TiledOutputFile::Data *ofd,
              Array<char>& tileBuffer,
	      int numScanLines,
	      int numPixelsPerScanLine)
{
    //
    // Convert the contents of a TiledOutputFile's tileBuffer from the 
    // machine's native representation to Xdr format. This function is called
    // by writeTile(), below, if the compressor wanted its input pixel data
    // in the machine's native format, but then failed to compress the data
    // (most compressors will expand rather than compress random input data).
    //
    // Note that this routine assumes that the machine's native representation
    // of the pixel data has the same size as the Xdr representation.  This
    // makes it possible to convert the pixel data in place, without an
    // intermediate temporary buffer.
    //

    //
    // Set these to point to the start of the tile.
    // We will write to toPtr, and read from fromPtr.
    //

    char *writePtr = tileBuffer;
    const char *readPtr = writePtr;

    //
    // Iterate over all scan lines in the tile.
    //

    for (int y = 0; y < numScanLines; ++y)
    {
	//
	// Iterate over all slices in the file.
	//

	for (unsigned int i = 0; i < ofd->slices.size(); ++i)
	{
	    const TOutSliceInfo &slice = ofd->slices[i];

	    //
	    // Convert the samples in place.
	    //
            
            convertInPlace (writePtr, readPtr, slice.type,
                            numPixelsPerScanLine);
	}
    }

    #ifdef DEBUG

	assert (writePtr == readPtr);

    #endif
}


//
// A TileBufferTask encapsulates the task of copying a tile from
// the user's framebuffer into a LineBuffer and compressing the data
// if necessary.
//

class TileBufferTask: public Task
{
  public:
                    
    TileBufferTask (TaskGroup *group,
                    TiledOutputFile::Data *ofd,
                    int number,
		    int dx, int dy,
		    int lx, int ly);
                    
    virtual ~TileBufferTask ();

    virtual void		execute ();
    
  private:

    TiledOutputFile::Data *	_ofd;
    TileBuffer *		_tileBuffer;
};


TileBufferTask::TileBufferTask
    (TaskGroup *group,
     TiledOutputFile::Data *ofd,
     int number,
     int dx, int dy,
     int lx, int ly)
:
    Task (group),
    _ofd (ofd),
    _tileBuffer (_ofd->getTileBuffer (number))
{
    //
    // Wait for the tileBuffer to become available
    //

    _tileBuffer->wait ();
    _tileBuffer->tileCoord = TileCoord (dx, dy, lx, ly);
}


TileBufferTask::~TileBufferTask ()
{
    //
    // Signal that the tile buffer is now free
    //

    _tileBuffer->post ();
}


void
TileBufferTask::execute ()
{
    try
    {
        //
        // First copy the pixel data from the frame buffer
	// into the tile buffer
        //
        // Convert one tile's worth of pixel data to
        // a machine-independent representation, and store
        // the result in _tileBuffer->buffer.
        //
    
        char *writePtr = _tileBuffer->buffer;
    
        Box2i tileRange = Imf::dataWindowForTile (_ofd->tileDesc,
                                                  _ofd->minX, _ofd->maxX,
                                                  _ofd->minY, _ofd->maxY,
                                                  _tileBuffer->tileCoord.dx,
                                                  _tileBuffer->tileCoord.dy,
                                                  _tileBuffer->tileCoord.lx,
                                                  _tileBuffer->tileCoord.ly);
    
        int numScanLines = tileRange.max.y - tileRange.min.y + 1;
        int numPixelsPerScanLine = tileRange.max.x - tileRange.min.x + 1;
    
        //
        // Iterate over the scan lines in the tile.
        //
        
        for (int y = tileRange.min.y; y <= tileRange.max.y; ++y)
        {
            //
            // Iterate over all image channels.
            //
    
            for (unsigned int i = 0; i < _ofd->slices.size(); ++i)
            {
                const TOutSliceInfo &slice = _ofd->slices[i];
    
                //
                // These offsets are used to facilitate both absolute
                // and tile-relative pixel coordinates.
                //
            
                int xOffset = slice.xTileCoords * tileRange.min.x;
                int yOffset = slice.yTileCoords * tileRange.min.y;
    
		//
		// Fill the tile buffer with pixel data.
		//

                if (slice.zero)
                {
                    //
                    // The frame buffer contains no data for this channel.
                    // Store zeroes in _data->tileBuffer.
                    //
                    
                    fillChannelWithZeroes (writePtr, _ofd->format, slice.type,
                                           numPixelsPerScanLine);
                }
                else
                {
                    //
                    // The frame buffer contains data for this channel.
                    //
    
                    const char *readPtr = slice.base +
                                          (y - yOffset) * slice.yStride +
                                          (tileRange.min.x - xOffset) *
                                          slice.xStride;

                    const char *endPtr  = readPtr +
                                          (numPixelsPerScanLine - 1) *
                                          slice.xStride;
                                        
                    copyFromFrameBuffer (writePtr, readPtr, endPtr,
                                         slice.xStride, _ofd->format,
                                         slice.type);
                }
            }
        }
        
        //
        // Compress the contents of the tileBuffer, 
        // and store the compressed data in the output file.
        //
    
        _tileBuffer->dataSize = writePtr - _tileBuffer->buffer;
        _tileBuffer->dataPtr = _tileBuffer->buffer;
    
        if (_tileBuffer->compressor)
        {
            const char *compPtr;

            int compSize = _tileBuffer->compressor->compressTile
                                                (_tileBuffer->dataPtr,
                                                 _tileBuffer->dataSize,
                                                 tileRange, compPtr);
    
            if (compSize < _tileBuffer->dataSize)
            {
                _tileBuffer->dataSize = compSize;
                _tileBuffer->dataPtr = compPtr;
            }
            else if (_ofd->format == Compressor::NATIVE)
            {
                //
                // The data did not shrink during compression, but
                // we cannot write to the file using native format,
                // so we need to convert the lineBuffer to Xdr.
                //
    
                convertToXdr (_ofd, _tileBuffer->buffer, numScanLines,
                              numPixelsPerScanLine);
            }
        }
    }
    catch (std::exception &e)
    {
        if (!_tileBuffer->hasException)
        {
            _tileBuffer->exception = e.what ();
            _tileBuffer->hasException = true;
        }
    }
    catch (...)
    {
        if (!_tileBuffer->hasException)
        {
            _tileBuffer->exception = "unrecognized exception";
            _tileBuffer->hasException = true;
        }
    }
}

} // namespace


TiledOutputFile::TiledOutputFile
    (const char fileName[],
     const Header &header,
     int numThreads)
:
    _data (new Data (true, numThreads))
{
    try
    {
	header.sanityCheck (true);
	_data->os = new StdOFStream (fileName);
	initialize (header);
    }
    catch (Iex::BaseExc &e)
    {
	delete _data;

	REPLACE_EXC (e, "Cannot open image file "
			"\"" << fileName << "\". " << e);
	throw;
    }
    catch (...)
    {
	delete _data;
        throw;
    }
}


TiledOutputFile::TiledOutputFile
    (OStream &os,
     const Header &header,
     int numThreads)
:
    _data (new Data (false, numThreads))
{
    try
    {
	header.sanityCheck(true);
	_data->os = &os;
	initialize (header);
    }
    catch (Iex::BaseExc &e)
    {
	delete _data;

	REPLACE_EXC (e, "Cannot open image file "
			"\"" << os.fileName() << "\". " << e);
	throw;
    }
    catch (...)
    {
	delete _data;
        throw;
    }
}


void
TiledOutputFile::initialize (const Header &header)
{
    _data->header = header;
    _data->lineOrder = _data->header.lineOrder();

    //
    // Check that the file is indeed tiled
    //

    _data->tileDesc = _data->header.tileDescription();

    //
    // Save the dataWindow information
    //

    const Box2i &dataWindow = _data->header.dataWindow();
    _data->minX = dataWindow.min.x;
    _data->maxX = dataWindow.max.x;
    _data->minY = dataWindow.min.y;
    _data->maxY = dataWindow.max.y;

    //
    // Precompute level and tile information to speed up utility functions
    //

    precalculateTileInfo (_data->tileDesc,
			  _data->minX, _data->maxX,
			  _data->minY, _data->maxY,
			  _data->numXTiles, _data->numYTiles,
			  _data->numXLevels, _data->numYLevels);       
    
    //
    // Determine the first tile coordinate that we will be writing
    // if the file is not RANDOM_Y.
    //
    
    _data->nextTileToWrite = (_data->lineOrder == INCREASING_Y)?
			       TileCoord (0, 0, 0, 0):
			       TileCoord (0, _data->numYTiles[0] - 1, 0, 0);

    _data->maxBytesPerTileLine =
	    calculateBytesPerPixel (_data->header) * _data->tileDesc.xSize;

    _data->tileBufferSize = _data->maxBytesPerTileLine * _data->tileDesc.ySize;
    
    //
    // Create all the TileBuffers and allocate their internal buffers
    //

    for (size_t i = 0; i < _data->tileBuffers.size(); i++)
    {
        _data->tileBuffers[i] = new TileBuffer (newTileCompressor
						  (_data->header.compression(),
						   _data->maxBytesPerTileLine,
						   _data->tileDesc.ySize,
						   _data->header));

        _data->tileBuffers[i]->buffer.resizeErase(_data->tileBufferSize);
    }

    _data->format = defaultFormat (_data->tileBuffers[0]->compressor);

    _data->tileOffsets = TileOffsets (_data->tileDesc.mode,
				      _data->numXLevels,
				      _data->numYLevels,
				      _data->numXTiles,
				      _data->numYTiles);

    _data->previewPosition = _data->header.writeTo (*_data->os, true);

    _data->tileOffsetsPosition = _data->tileOffsets.writeTo (*_data->os);
    _data->currentPosition = _data->os->tellp();
}


TiledOutputFile::~TiledOutputFile ()
{
    if (_data)
    {
        {
            if (_data->tileOffsetsPosition > 0)
            {
                try
                {
                    _data->os->seekp (_data->tileOffsetsPosition);
                    _data->tileOffsets.writeTo (*_data->os);
                }
                catch (...)
                {
                    //
                    // We cannot safely throw any exceptions from here.
                    // This destructor may have been called because the
                    // stack is currently being unwound for another
                    // exception.
                    //
                }
            }
        }
        
        delete _data;
    }
}


const char *
TiledOutputFile::fileName () const
{
    return _data->os->fileName();
}


const Header &
TiledOutputFile::header () const
{
    return _data->header;
}


void	
TiledOutputFile::setFrameBuffer (const FrameBuffer &frameBuffer)
{
    Lock lock (*_data);

    //
    // Check if the new frame buffer descriptor
    // is compatible with the image file header.
    //

    const ChannelList &channels = _data->header.channels();

    for (ChannelList::ConstIterator i = channels.begin();
	 i != channels.end();
	 ++i)
    {
	FrameBuffer::ConstIterator j = frameBuffer.find (i.name());

	if (j == frameBuffer.end())
	    continue;

	if (i.channel().type != j.slice().type)
	    THROW (Iex::ArgExc, "Pixel type of \"" << i.name() << "\" channel "
				"of output file \"" << fileName() << "\" is "
				"not compatible with the frame buffer's "
				"pixel type.");

	if (j.slice().xSampling != 1 || j.slice().ySampling != 1)
	    THROW (Iex::ArgExc, "All channels in a tiled file must have"
				"sampling (1,1).");
    }
    
    //
    // Initialize slice table for writePixels().
    //

    vector<TOutSliceInfo> slices;

    for (ChannelList::ConstIterator i = channels.begin();
	 i != channels.end();
	 ++i)
    {
	FrameBuffer::ConstIterator j = frameBuffer.find (i.name());

	if (j == frameBuffer.end())
	{
	    //
	    // Channel i is not present in the frame buffer.
	    // In the file, channel i will contain only zeroes.
	    //

	    slices.push_back (TOutSliceInfo (i.channel().type,
					     0, // base
					     0, // xStride,
					     0, // yStride,
					     true)); // zero
	}
	else
	{
	    //
	    // Channel i is present in the frame buffer.
	    //

	    slices.push_back (TOutSliceInfo (j.slice().type,
					     j.slice().base,
					     j.slice().xStride,
					     j.slice().yStride,
					     false, // zero
                                             (j.slice().xTileCoords)? 1: 0,
                                             (j.slice().yTileCoords)? 1: 0));
	}
    }

    //
    // Store the new frame buffer.
    //

    _data->frameBuffer = frameBuffer;
    _data->slices = slices;
}


const FrameBuffer &
TiledOutputFile::frameBuffer () const
{
    Lock lock (*_data);
    return _data->frameBuffer;
}


void	
TiledOutputFile::writeTiles (int dx1, int dx2, int dy1, int dy2,
                             int lx, int ly)
{
    try
    {
        Lock lock (*_data);

        if (_data->slices.size() == 0)
	    throw Iex::ArgExc ("No frame buffer specified "
			       "as pixel data source.");

	if (!isValidTile (dx1, dy1, lx, ly) || !isValidTile (dx2, dy2, lx, ly))
	    throw Iex::ArgExc ("Tile coordinates are invalid.");

        //
        // Determine the first and last tile coordinates in both dimensions
        // based on the file's lineOrder
        //
                               
        if (dx1 > dx2)
            swap (dx1, dx2);
        
        if (dy1 > dy2)
            swap (dy1, dy2);
        
        int dyStart = dy1;
	int dyStop  = dy2 + 1;
	int dY      = 1;
    
        if (_data->lineOrder == DECREASING_Y)
        {