vidl2_image_list_istream Class Reference

#include <vidl2_image_list_istream.h>

Inheritance diagram for vidl2_image_list_istream:

[legend]List of all members.

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Detailed Description

A video input stream from a list of images on disk.

This istream will try to open and validate (but not read image data from) every file in a list of file paths. The paths to valid image files are maintained, but only one image is opened at a time. Keeping a list of open file descriptors (via vil_image_resource_sptr) was found to be problematic. The number of simultaneously open files is limited on many platforms. The paths are tested for validity at the "open" stage rather than the "stream" stage so that we have random access to the frames (i.e. the stream is seekable).

Definition at line 27 of file vidl2_image_list_istream.h.

Public Member Functions
	vidl2_image_list_istream ()
	Constructor - default.
	vidl2_image_list_istream (const vcl_string &glob)
	Constructor - from a file glob string.
	vidl2_image_list_istream (const vcl_vector< vcl_string > &paths)
	Constructor - from a vector of file paths.
virtual	~vidl2_image_list_istream ()
	Destructor.
virtual bool	open (const vcl_string &glob)
	Open a new stream using a file glob (see vul_file_iterator).
virtual bool	open (const vcl_vector< vcl_string > &paths)
	Open a new stream using a vector of file paths.
virtual void	close ()
	Close the stream.
virtual bool	is_open () const
	Return true if the stream is open for reading.
virtual bool	is_valid () const
	Return true if the stream is in a valid state.
virtual bool	is_seekable () const
	Return true if the stream support seeking.
virtual unsigned int	frame_number () const
	Return the current frame number.
virtual bool	advance ()
	Advance to the next frame (but do not open the next image).
virtual vidl2_frame_sptr	read_frame ()
	Read the next frame from the stream.
virtual vidl2_frame_sptr	current_frame ()
	Return the current frame in the stream.
virtual bool	seek_frame (unsigned int frame_number)
	Seek to the given frame number (but do not load the image).
void	ref ()
	Increment reference count.
void	unref ()
	Decrement reference count.
int	ref_count () const
	Number of objects referring to this data.
Private Attributes
vcl_vector< vcl_string >	image_paths_
	The vector of images.
unsigned int	index_
	The current index.
vidl2_frame_sptr	current_frame_
	The current frame (cached).

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Constructor & Destructor Documentation

vidl2_image_list_istream::vidl2_image_list_istream (   )

Constructor - default. Definition at line 30 of file vidl2_image_list_istream.cxx.

vidl2_image_list_istream::vidl2_image_list_istream (  const vcl_string &  glob  )

Constructor - from a file glob string. Definition at line 36 of file vidl2_image_list_istream.cxx.

vidl2_image_list_istream::vidl2_image_list_istream (  const vcl_vector< vcl_string > &  paths  )

Constructor - from a vector of file paths.

virtual vidl2_image_list_istream::~vidl2_image_list_istream (   )  [inline, virtual]

Destructor. Definition at line 41 of file vidl2_image_list_istream.h.

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Member Function Documentation

bool vidl2_image_list_istream::advance (   )  [virtual]

Advance to the next frame (but do not open the next image). Implements vidl2_istream. Definition at line 99 of file vidl2_image_list_istream.cxx.

void vidl2_image_list_istream::close (   )  [virtual]

Close the stream. Implements vidl2_istream. Definition at line 88 of file vidl2_image_list_istream.cxx.

vidl2_frame_sptr vidl2_image_list_istream::current_frame (   )  [virtual]

Return the current frame in the stream. Implements vidl2_istream. Definition at line 120 of file vidl2_image_list_istream.cxx.

virtual unsigned int vidl2_image_list_istream::frame_number (   )  const [inline, virtual]

Return the current frame number. Implements vidl2_istream. Definition at line 67 of file vidl2_image_list_istream.h.

virtual bool vidl2_image_list_istream::is_open (   )  const [inline, virtual]

Return true if the stream is open for reading. Implements vidl2_istream. Definition at line 57 of file vidl2_image_list_istream.h.

virtual bool vidl2_image_list_istream::is_seekable (   )  const [inline, virtual]

Return true if the stream support seeking. Implements vidl2_istream. Definition at line 64 of file vidl2_image_list_istream.h.

virtual bool vidl2_image_list_istream::is_valid (   )  const [inline, virtual]

Return true if the stream is in a valid state. Implements vidl2_istream. Definition at line 60 of file vidl2_image_list_istream.h.

bool vidl2_image_list_istream::open (  const vcl_vector< vcl_string > &  paths  )  [virtual]

Open a new stream using a vector of file paths. Note: all files are tested and only valid image files are retained Definition at line 70 of file vidl2_image_list_istream.cxx.

bool vidl2_image_list_istream::open (  const vcl_string &  glob  )  [virtual]

Open a new stream using a file glob (see vul_file_iterator). Note: files are loaded in alphanumeric order by path name Definition at line 44 of file vidl2_image_list_istream.cxx.

vidl2_frame_sptr vidl2_image_list_istream::read_frame (   )  [virtual]

Read the next frame from the stream. Implements vidl2_istream. Definition at line 111 of file vidl2_image_list_istream.cxx.

void vidl2_istream::ref (   )  [inline, inherited]

Increment reference count. Definition at line 63 of file vidl2_istream.h.

int vidl2_istream::ref_count (   )  const [inline, inherited]

Number of objects referring to this data. Definition at line 69 of file vidl2_istream.h.

bool vidl2_image_list_istream::seek_frame (  unsigned int  frame_number  )  [virtual]

Seek to the given frame number (but do not load the image). Returns: true if successful Implements vidl2_istream. Definition at line 137 of file vidl2_image_list_istream.cxx.

void vidl2_istream::unref (   )  [inline, inherited]

Decrement reference count. Definition at line 66 of file vidl2_istream.h.

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Member Data Documentation

vidl2_frame_sptr vidl2_image_list_istream::current_frame_ [private]

The current frame (cached). Definition at line 91 of file vidl2_image_list_istream.h.

vcl_vector<vcl_string> vidl2_image_list_istream::image_paths_ [private]

The vector of images. Definition at line 85 of file vidl2_image_list_istream.h.

unsigned int vidl2_image_list_istream::index_ [private]

The current index. Definition at line 88 of file vidl2_image_list_istream.h.

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The documentation for this class was generated from the following files:

• contrib/brl/bbas/vidl2/vidl2_image_list_istream.h
• contrib/brl/bbas/vidl2/vidl2_image_list_istream.cxx

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