I have a Web Service that takes a photo through a POST statement and returns a modified copy of that photo back. We are making changes to the way it processes the photo, and I want to verify that the photo at least has different properties coming back than it did before our changes went into effect.
The photo is being returned as a byte stream inside one of the fields of a JSON object. I can analyze the JSON object pretty easily, but I'm trying to figure out how to get the byte stream into an Java image object so that I can get its dimensions.
Possible duplicate of this question
... I'm trying to figure out how to get the byte stream into an Java image object so that i can get its dimensions.
I'd suggest using a BufferedImage in the following format/snippet. Note: I load my image in from disk for the example and use try-with-resources (which you may revert to 1.6-prior if needed).
String fp = "C:\\Users\\Nick\\Desktop\\test.png";
try (FileInputStream fis = new FileInputStream(new File(fp));
BufferedInputStream bis = new BufferedInputStream(fis)) {
BufferedImage img = ImageIO.read(bis);
final int w = img.getWidth(null);
final int h = img.getHeight(null);
}
You can use:
OS Process Sampler and 3rd-party tool like ImageMagick
JSR223 Test Elements, to wit
JSR223 PreProcessor to get information on the photo, you're trying to upload
JSR223 PostProcessor to get information on the photo, returned by the Web Service
JSR223 Assertion to compare two photos
Depending on what parameters you need to compare you can use ImageIO API (out of the box, bundled with JDK), Commons Imaging, ImageJ and so on.
Related
My idea is to divide a big response text into small parts to load them concurrently.
The following code helps me open stream from an URL but I want to load its whole content from multithreads to optimize performance, then I will merge them into a single result. However, the method return a ReadableByteChannel which cannot specify the start position and I have to transfer it linearly:
URL url = new URL("link");
InputStream fromStream = url.openStream();
ReadableByteChannel fromChannel = Channels.newChannel(fromStream);
Is there any way to specify the position like SeekableByteChannel (seem likes this interface only works with file)? Thanks you :D
If you can manipulate the request before it's a stream then yes, you would use the Range http header to specify the chunk of data you wanted...
See Downloading a portion of a File using HTTP Requests
If not then you will manually have to read past the data you don't need.
See Given a Java InputStream, how can I determine the current offset in the stream?
I will modify and add Tiff-Tags to existing tif-files with java. JAI imageio crashed, because it could not deal with certain tags from Tiff 6.0. Apache Commons-Imaging seems to be able to deal with these tags. But I have no idea, how to do that. I found a post here, I used for beginning (How to embed ICC_Profile in TiffOutputSet).
Using the example code creates an image, which I can't open because of an LZW error. If I use the Imaging.writeImage(...) methods, It changes the color model from 8Bit to 24Bit and the Exif metadata hase gone.
What i have done is:
bufferedImage = Imaging.getBufferedImage(srcTiff);
byte[] imageBytes = Imaging.writeImageToBytes(tifFile, imageFormat, optional_params)
exifDirectory = tiffOutputSet.getOrCreateRootDirectory();
...
TiffImageWriterLossLess lossLessWriter = new TiffImageWriterLossless(imageBytes);
os = new FileOutputStream(tmpFile);
os = new BufferedOutputStream(os);
lossLessWriter.writeImage(bufferedImage, os, image_params);
Playing around with image_params, like compression or defining the outputset as params, results in different issues. But one is constant, the destImage is bigger then the src image, even when the source image is 24 bit like the dest image.
How could I get Commons-Imaging work for me?
I can respond to the destImage bigger than the src, it is because TIFF images have a compression that is not carried over when the image is read into memory. On writing the image back to storage, you must apply the compression explicitly.
I would like to know if is possible get the image via POST method with a HTTP server implemented in Java (With a simple input file form). I already implemented the Java server but I can only get text files via POST method it's because that the my application only copies the file content to another empty file creating the same file with the same characteristics. This does not work with image file or other files, this can only work with text file.
Anyone know how to implement it with images?
Some coordinates would be of great help!
Thanks in advance!
As far as i know you should create something like it:
Server-side: If you use a servlet that receive data in post you have to get the outputStream from the response. Once you have it it is done because you write the data image on the stream.
For example let's suppose your image is a file stored in the server you could do:
response.setContentLength((int) fileSize);
byte b[] = new byte[1024];
while ( fOutStream.read(b) != -1)
response.getOutputStream().write(b);
fOutStream.close() ;
Where the fOutStream is the source stream (your image).
I am struggling with the transfer of a simple jpeg file inside an ID3v2 tag from c++ over a TCP socket to java (Android). The library "taglib" offers to extract this file and I am able to save the jpeg as a new file.
The send function looks like this
char *parameter_full = new char[f3->picture().size()+2];
sprintf(parameter_full,"%s\n\0",f3->picture().data());
// send
result = send(c,parameter_full,strlen(parameter_full),0);
delete[] parameter_full;
where
f3->picture().data() returns a pointer to the internal data structure (it returns char*) and
f3->picture().size() returns the size of the array.
Then Android receives it with
String imageString = inFromServer.readLine();
byte[] imageBytes = imageString.getBytes();
Bitmap cover = BitmapFactory.decodeByteArray(imageBytes,0,imageBytes.length);
But somehow decodeByteArray always returns null. My idea is that Java doesn't receive the image correctly because imageString only consists of 4 characters...while the extracted jpeg file has a size of 12.7 KB.
But what has gone wrong?
Martin
You shouldn't use string functions on byte data because 0 values are taken as string terminators. Try looking into memcpy on the C++ side if you need to copy the char* and also the byte[] read functions for InputStream on the Java side.
It's possible to convert an Image object To FormFile object ..?
Are you referring to the Apache Struts FormFile? If so, then you'd probably want to be creating a CommonsMultipartRequestHandler.CommonsFormFile which simply wraps an implementation of the FileItem interface, the only one of which I could find (that isn't deprecated) is a DiskFileItem. But this is for content that's been received within a multipart/form-data POST request, and not something that I would have thought you'd have an Image object for. Which makes me wonder what exactly you're trying to accomplish.
update:
Based on your feedback I would imagine you could create a BufferedImage object based on the FileItem, which should then be able to be manipulated:
InputStream is = fileItem.getInputStream();
BufferedImage image = ImageIO.read(is);
Once you're happy with the BufferedImage that you've tweaked you can write it to the file system using ImageIO.write().