几点TIFF的说明

一：TIFF读图工具

1.QuaPath:https://github.com/qupath

2.ASAP:https://github.com/computationalpathologygroup/ASAP

 

二： TIFF 格式限制

TIFF格式限制了其文件只能存储最大4G，超出4个G无法存储，打破该限制的方法为使用本系列所推荐的方法编译最新的4.1版本，然后将文件存储为bigtiff

如何存储为bigTIFF？

只需要在TIFFOpen函数的参数里面增加一个选项即可

//w 代表写文件，8 代表bigtiff ,4 代表标准tiff,默认为4
TIFFOpen(pcPath, "w8");

 

三：存储tile 图像

bool SaveTile(const uchar *pucTile, uchar *pucJpeg, const int nL, const int nT,
    const int nR, const int nB, const int nLayer, const int nFocus)
{
 
    LOG_E("left = %d,top = %d,bottom = %d,right = %d, nLayer=%d,nFocus=%d", nL, nT, nB, nR,nLayer,nFocus);
 
    LAYER_S &stLayer = m_pD->stTmap.stLayers[nLayer];
 
    
    const int nWidth = nR - nL;
    const int nHeight = nB - nT;
    int nLength = 0;
 
 
    try
    {
        TIFFSetDirectory(m_pD->pfFile, nLayer);
        TIFFSetField(m_pD->pfFile, TIFFTAG_IMAGEWIDTH, stLayer.nWidth);
        TIFFSetField(m_pD->pfFile, TIFFTAG_IMAGELENGTH, stLayer.nHeight);
        TIFFSetField(m_pD->pfFile, TIFFTAG_ROWSPERSTRIP, stLayer.nHeight);
 
        TIFFSetField(m_pD->pfFile, TIFFTAG_TILEWIDTH, m_pD->nTileW);
        TIFFSetField(m_pD->pfFile, TIFFTAG_TILELENGTH, m_pD->nTileH);
        TIFFSetField(m_pD->pfFile, TIFFTAG_SUBFILETYPE, FILETYPE_REDUCEDIMAGE);
        TIFFSetField(m_pD->pfFile, TIFFTAG_BITSPERSAMPLE, 8);
        TIFFSetField(m_pD->pfFile, TIFFTAG_SAMPLESPERPIXEL, 3);
        TIFFSetField(m_pD->pfFile, TIFFTAG_PLANARCONFIG, PLANARCONFIG_CONTIG);
 
        TIFFSetField(m_pD->pfFile, TIFFTAG_COMPRESSION, COMPRESSION_JPEG);
        TIFFSetField(m_pD->pfFile, TIFFTAG_PHOTOMETRIC, PHOTOMETRIC_RGB);
 
        /*int nJpegQuality = 60;
        TIFFSetField(m_pD->pfFile, TIFFTAG_JPEGQUALITY, nJpegQuality);*/
        if (nLayer == 0)
        {
            float fPixelSize = 0.0f;
            int nScale = 0;
            GetScanScale(nScale);
            GetPixelSize(fPixelSize);
            fPixelSize = fPixelSize * 100 / max(1, nScale);
            TIFFSetField(m_pD->pfFile, TIFFTAG_XRESOLUTION, 1.0 / (fPixelSize / 10));
            TIFFSetField(m_pD->pfFile, TIFFTAG_YRESOLUTION, 1.0 / (fPixelSize / 10));
            TIFFSetField(m_pD->pfFile, TIFFTAG_RESOLUTIONUNIT, 3);
        }
 

        
        // save tile information
        const int nTileRow = nT / m_pD->nTileH;
        const int nTileCol = nL / m_pD->nTileW;
        int tiffIndex = nTileRow * (stLayer.nWidth / m_pD->nTileW) + nTileCol;
 
 
        TIFFWriteEncodedTile(m_pD->pfFile, tiffIndex, (void *)pucTile, m_pD->nTileW * m_pD->nTileH * 3);
 
        TIFFWriteDirectory(m_pD->pfFile);
}