问题
I am having issues converting a png to tiff. The conversion goes fine, but the image is huge. I think the issue is that I am not doing the compression correctly? Anyone have any suggestions??
Here is the code sample
public static void test() throws IOException {
// String fileName = "4958813_1";
String fileName = "4848970_1";
String inFileType = ".PNG";
String outFileType = ".TIFF";
ImageIO.scanForPlugins();
File fInputFile = new File("I:/HPF/UU/" + fileName + inFileType);
InputStream fis = new BufferedInputStream(new FileInputStream(
fInputFile));
PNGImageReaderSpi spi = new PNGImageReaderSpi();
ImageReader reader = spi.createReaderInstance();
ImageInputStream iis = ImageIO.createImageInputStream(fis);
reader.setInput(iis, true);
BufferedImage bi = reader.read(0);
TIFFImageWriterSpi tiffspi = new TIFFImageWriterSpi();
ImageWriter writer = tiffspi.createWriterInstance();
//Iterator<ImageWriter> iter = ImageIO.getImageWritersByFormatName("TIFF");
//ImageWriter writer = iter.next();
ImageWriteParam param = writer.getDefaultWriteParam();
param.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);
param.setCompressionType("LZW");
param.setCompressionQuality(0.5f);
File fOutputFile = new File("I:\\HPF\\UU\\" + fileName + outFileType);
ImageOutputStream ios = ImageIO.createImageOutputStream(fOutputFile);
writer.setOutput(ios);
writer.write(bi);
}
回答1:
Writer.getDefaultWriteParam()
only creates an ImageWriteParam
object, it doesn't link it back to anything else.
I don't see any mechanism in your code for your modified param
object to be subsequently used in the ImageWriter
.
I believe that instead of:
writer.write(bi);
you need to use:
writer.write(null, new IIOImage(bi, null, null), param);
回答2:
I don't know Java IO, but generally you want to look at a few things
- Can you use JPEG compression instead of LZW?
- See how to set the TIFF strip size -- if small size is what you want, set it to the height of the image.
Edit: Looks like a TiffWriteParam has the following methods
tiffWriteParam.setTilingMode(ImageWriteParam.MODE_EXPLICIT);
tiffWriteParam.setTiling(imageWidth, imageHeight, 0, 0);
set the imageWidth and imageHeight vars to your image's size. The downside is that it will be slower to read out regions of the image.
来源:https://stackoverflow.com/questions/281512/tiff-compression-using-java-imageio