HashOutputSeries Class Reference

FrameOstream subclass that writes image hashes to an output file. More...

#include <Transport/HashOutputSeries.H>

Inheritance diagram for HashOutputSeries:

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Collaboration diagram for HashOutputSeries:

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List of all members.

Classes
struct	Impl
Public Member Functions
	HashOutputSeries (OptionManager &mgr)
	Constructor.
virtual	~HashOutputSeries ()
	Destructor.
virtual void	setConfigInfo (const std::string &filename)
	Override from FrameOstream; just calls setFileName().
virtual bool	setFrameNumber (int n)
	Set the current frame number and remember it.
virtual void	writeFrame (const GenericFrame &frame, const std::string &shortname, const FrameInfo &auxinfo)
	Write a image hash to the output file.
virtual void	closeStream (const std::string &shortname)
	No-op.
void	setFileName (const std::string &s)
	Specify the output filename.

Detailed Description

FrameOstream subclass that writes image hashes to an output file.

To try out HashOutputSeries, you can for example do the following using bin/stream to generate a listing on stderr of 100 32-bit hashes of 300x300 random images like this:

./bin/stream --in=random:300x300 --in-echo=hash:stderr \ --input-frames=0-99

which will generate output like the following:

000000 5b380a30 0 % input-echo 000001 1d108dc8 0 % input-echo 000002 5c0e58aa 0 % input-echo 000003 cb34047b 0 % input-echo 000004 f800c826 0 % input-echo 000005 6386062a 0 % input-echo 000006 30ed69d6 0 % input-echo

where the first column is the frame number, the second column is the hash, and the third column is a 0 or 1 indicating whether we've seen that hash value previously in this run -- note that a value of 1 doesn't necessarily imply a hash-function collision; it could be that the input frames were exactly the same! The last column, after a matlab-comment character (%), is the image name as it was passed to writeRGB() or writeGray() or writeFloat().

If the filename given to HashOutputSeries is "", "-", "stdout", or "STDOUT" then the output goes to stdout, likewise "stderr" or "STDERR" sends output to stderr, and anything else will be interpreted as a literal filename to which output should be written.

Definition at line 75 of file HashOutputSeries.H.