Panda3D
 All Classes Functions Variables Enumerations
Classes | Public Member Functions | Static Public Member Functions | List of all members
MovieVideoCursor Class Reference

A MovieVideo is actually any source that provides a sequence of video frames. More...

#include "movieVideoCursor.h"

Inheritance diagram for MovieVideoCursor:
TypedWritableReferenceCount TypedWritable ReferenceCount TypedObject MemoryBase MemoryBase FfmpegVideoCursor InkblotVideoCursor

Classes

class  Buffer
 

Public Member Functions

bool aborted () const
 Returns true if the video has aborted prematurely. More...
 
virtual void apply_to_texture (const Buffer *buffer, Texture *t, int page)
 Stores this buffer's contents in the indicated texture. More...
 
virtual void apply_to_texture_alpha (const Buffer *buffer, Texture *t, int page, int alpha_src)
 Copies this buffer's contents into the alpha channel of the supplied texture. More...
 
virtual void apply_to_texture_rgb (const Buffer *buffer, Texture *t, int page)
 Copies this buffer's contents into the RGB channels of the supplied texture. More...
 
bool can_seek () const
 Returns true if the movie can seek. More...
 
bool can_seek_fast () const
 Returns true if seek operations are constant time. More...
 
virtual int complete_pointers (TypedWritable **plist, BamReader *manager)
 Receives an array of pointers, one for each time manager->read_pointer() was called in fillin(). More...
 
virtual TypeHandle force_init_type ()
 
int get_num_components () const
 Returns 4 if the movie has an alpha channel, 3 otherwise. More...
 
virtual TypeHandle get_type () const
 
double length () const
 Returns the length of the movie. More...
 
 PT (MovieVideo) get_source() const
 
virtual PT (Buffer) fetch_buffer()
 
bool ready () const
 Returns true if the cursor is a streaming source, and if a video frame is ready to be read. More...
 
virtual bool set_time (double timestamp, int loop_count)
 Updates the cursor to the indicated time. More...
 
void setup_texture (Texture *tex) const
 Set up the specified Texture object to contain content from this movie. More...
 
int size_x () const
 
int size_y () const
 Get the vertical size of the movie. More...
 
bool streaming () const
 Returns true if the video frames are being "pushed" at us by something that operates at its own speed - for example, a webcam. More...
 
virtual void write_datagram (BamWriter *manager, Datagram &dg)
 Writes the contents of this object to the datagram for shipping out to a Bam file. More...
 
- Public Member Functions inherited from TypedWritableReferenceCount
 TypedWritableReferenceCount (const TypedWritableReferenceCount &copy)
 
virtual ReferenceCountas_reference_count ()
 Returns the pointer cast to a ReferenceCount pointer, if it is in fact of that type. More...
 
void operator= (const TypedWritableReferenceCount &copy)
 
- Public Member Functions inherited from TypedWritable
 TypedWritable (const TypedWritable &copy)
 
string encode_to_bam_stream () const
 Converts the TypedWritable object into a single stream of data using a BamWriter, and returns that data as a string string. More...
 
bool encode_to_bam_stream (string &data, BamWriter *writer=NULL) const
 Converts the TypedWritable object into a single stream of data using a BamWriter, and stores that data in the indicated string. More...
 
virtual void finalize (BamReader *manager)
 Called by the BamReader to perform any final actions needed for setting up the object after all objects have been read and all pointers have been completed. More...
 
UpdateSeq get_bam_modified () const
 Returns the current bam_modified counter. More...
 
void mark_bam_modified ()
 Increments the bam_modified counter, so that this object will be invalidated and retransmitted on any open bam streams. More...
 
void operator= (const TypedWritable &copy)
 
virtual bool require_fully_complete () const
 Some objects require all of their nested pointers to have been completed before the objects themselves can be completed. More...
 
virtual void update_bam_nested (BamWriter *manager)
 Called by the BamWriter when this object has not itself been modified recently, but it should check its nested objects for updates. More...
 
- Public Member Functions inherited from TypedObject
 TypedObject (const TypedObject &copy)
 
TypedObjectas_typed_object ()
 Returns the object, upcast (if necessary) to a TypedObject pointer. More...
 
const TypedObjectas_typed_object () const
 Returns the object, upcast (if necessary) to a TypedObject pointer. More...
 
int get_best_parent_from_Set (const std::set< int > &) const
 
int get_type_index () const
 Returns the internal index number associated with this object's TypeHandle, a unique number for each different type. More...
 
bool is_exact_type (TypeHandle handle) const
 Returns true if the current object is the indicated type exactly. More...
 
bool is_of_type (TypeHandle handle) const
 Returns true if the current object is or derives from the indicated type. More...
 
void operator= (const TypedObject &copy)
 
- Public Member Functions inherited from ReferenceCount
int get_ref_count () const
 Returns the current reference count. More...
 
WeakReferenceListget_weak_list () const
 Returns the WeakReferenceList associated with this ReferenceCount object. More...
 
bool has_weak_list () const
 Returns true if this particular ReferenceCount object has a WeakReferenceList created, false otherwise. More...
 
void local_object ()
 This function should be called, once, immediately after creating a new instance of some ReferenceCount-derived object on the stack. More...
 
void ref () const
 Explicitly increments the reference count. More...
 
bool test_ref_count_integrity () const
 Does some easy checks to make sure that the reference count isn't completely bogus. More...
 
bool test_ref_count_nonzero () const
 Does some easy checks to make sure that the reference count isn't zero, or completely bogus. More...
 
virtual bool unref () const
 Explicitly decrements the reference count. More...
 
void weak_ref (WeakPointerToVoid *ptv)
 Adds the indicated PointerToVoid as a weak reference to this object. More...
 
void weak_unref (WeakPointerToVoid *ptv)
 Removes the indicated PointerToVoid as a weak reference to this object. More...
 

Static Public Member Functions

static TypeHandle get_class_type ()
 
static void init_type ()
 
- Static Public Member Functions inherited from TypedWritableReferenceCount
static TypeHandle get_class_type ()
 
static void init_type ()
 
static PT (TypedWritableReferenceCount) decode_from_bam_stream(const string &data
 
- Static Public Member Functions inherited from TypedWritable
static bool decode_raw_from_bam_stream (TypedWritable *&ptr, ReferenceCount *&ref_ptr, const string &data, BamReader *reader=NULL)
 Reads the string created by a previous call to encode_to_bam_stream(), and extracts the single object on that string. More...
 
static TypeHandle get_class_type ()
 
static void init_type ()
 
- Static Public Member Functions inherited from TypedObject
static TypeHandle get_class_type ()
 
static void init_type ()
 This function is declared non-inline to work around a compiler bug in g++ 2.96. More...
 
- Static Public Member Functions inherited from ReferenceCount
static TypeHandle get_class_type ()
 
static void init_type ()
 

Additional Inherited Members

- Public Attributes inherited from TypedWritableReferenceCount
static BamReaderreader = NULL)
 
- Static Public Attributes inherited from TypedWritable
static TypedWritable *const Null = (TypedWritable*)0L
 

Detailed Description

A MovieVideo is actually any source that provides a sequence of video frames.

That could include an AVI file, a digital camera, or an internet TV station. A MovieVideoCursor is a handle that lets you read data sequentially from a MovieVideo.

Thread safety: each individual MovieVideoCursor must be owned and accessed by a single thread. It is OK for two different threads to open the same file at the same time, as long as they use separate MovieVideoCursor objects.

Definition at line 45 of file movieVideoCursor.h.

Member Function Documentation

bool MovieVideoCursor::aborted ( ) const
inline

Returns true if the video has aborted prematurely.

For example, this could occur if the Movie was actually an internet TV station, and the connection was lost. Reaching the normal end of the video does not constitute an 'abort' condition.

Definition at line 129 of file movieVideoCursor.I.

void MovieVideoCursor::apply_to_texture ( const Buffer buffer,
Texture t,
int  page 
)
virtual
void MovieVideoCursor::apply_to_texture_alpha ( const Buffer buffer,
Texture t,
int  page,
int  alpha_src 
)
virtual

Copies this buffer's contents into the alpha channel of the supplied texture.

The RGB channels of the texture are not touched.

Definition at line 190 of file movieVideoCursor.cxx.

References Texture::get_component_width(), Texture::get_expected_ram_page_size(), get_num_components(), Texture::get_num_components(), Texture::get_x_size(), Texture::get_y_size(), Texture::modify_ram_image(), Texture::set_keep_ram_image(), and size_y().

void MovieVideoCursor::apply_to_texture_rgb ( const Buffer buffer,
Texture t,
int  page 
)
virtual

Copies this buffer's contents into the RGB channels of the supplied texture.

The alpha channel of the texture is not touched.

Definition at line 247 of file movieVideoCursor.cxx.

References Texture::get_component_width(), Texture::get_expected_ram_page_size(), get_num_components(), Texture::get_num_components(), Texture::get_x_size(), Texture::get_y_size(), Texture::modify_ram_image(), Texture::set_keep_ram_image(), and size_y().

bool MovieVideoCursor::can_seek ( ) const
inline

Returns true if the movie can seek.

If this is true, seeking is still not guaranteed to be fast: for some movies, seeking is implemented by rewinding to the beginning and then fast-forwarding to the desired location. Even if the movie cannot seek, the fetch methods can still advance to an arbitrary location by reading frames and discarding them. However, to move backward, can_seek must return true.

Definition at line 105 of file movieVideoCursor.I.

bool MovieVideoCursor::can_seek_fast ( ) const
inline

Returns true if seek operations are constant time.

Definition at line 115 of file movieVideoCursor.I.

int MovieVideoCursor::complete_pointers ( TypedWritable **  p_list,
BamReader manager 
)
virtual

Receives an array of pointers, one for each time manager->read_pointer() was called in fillin().

Returns the number of pointers processed.

Reimplemented from TypedWritable.

Definition at line 332 of file movieVideoCursor.cxx.

References TypedWritable::complete_pointers().

int MovieVideoCursor::get_num_components ( ) const
inline

Returns 4 if the movie has an alpha channel, 3 otherwise.

Definition at line 52 of file movieVideoCursor.I.

Referenced by apply_to_texture(), apply_to_texture_alpha(), apply_to_texture_rgb(), and setup_texture().

double MovieVideoCursor::length ( ) const
inline

Returns the length of the movie.

Some kinds of Movie, such as internet TV station, might not have a predictable length. In that case, the length will be set to a very large number: 1.0E10. If the internet TV station goes offline, the video or audio stream will set its abort flag. Reaching the end of the movie (ie, the specified length) normally does not cause the abort flag to be set.

The video and audio streams produced by get_video and get_audio are always of unlimited duration - you can always read another video frame or another audio sample. This is true even if the specified length is reached, or an abort is flagged. If either stream runs out of data, it will synthesize blank video frames and silent audio samples as necessary to satisfy read requests.

Some AVI files have incorrect length values encoded into them - usually, they're a second or two long or short. When playing such an AVI using the Movie class, you may see a slightly truncated video, or a slightly elongated video (padded with black frames). There are utilities out there to fix the length values in AVI files.

Definition at line 88 of file movieVideoCursor.I.

bool MovieVideoCursor::ready ( ) const
inline

Returns true if the cursor is a streaming source, and if a video frame is ready to be read.

For non- streaming sources, this is always false.

Definition at line 162 of file movieVideoCursor.I.

bool MovieVideoCursor::set_time ( double  timestamp,
int  loop_count 
)
virtual

Updates the cursor to the indicated time.

If loop_count >= 1, the time is clamped to the movie's length * loop_count. If loop_count <= 0, the time is understood to be modulo the movie's length.

Returns true if a new frame is now available, false otherwise. If this returns true, you should immediately follow this with exactly *one* call to fetch_buffer().

If the movie reports that it can_seek, you may also specify a time value less than the previous value you passed to set_time(). Otherwise, you may only specify a time value greater than or equal to the previous value.

If the movie reports that it can_seek, it doesn't mean that it can do so quickly. It may have to rewind the movie and then fast forward to the desired location. Only if can_seek_fast returns true can it seek rapidly.

Reimplemented in FfmpegVideoCursor, and InkblotVideoCursor.

Definition at line 103 of file movieVideoCursor.cxx.

void MovieVideoCursor::setup_texture ( Texture tex) const

Set up the specified Texture object to contain content from this movie.

This should be called once, not every frame.

Definition at line 68 of file movieVideoCursor.cxx.

References Texture::adjust_this_size(), get_num_components(), Texture::set_pad_size(), Texture::setup_texture(), and size_y().

int MovieVideoCursor::size_y ( ) const
inline

Get the vertical size of the movie.

Definition at line 41 of file movieVideoCursor.I.

Referenced by apply_to_texture(), apply_to_texture_alpha(), apply_to_texture_rgb(), and setup_texture().

bool MovieVideoCursor::streaming ( ) const
inline

Returns true if the video frames are being "pushed" at us by something that operates at its own speed - for example, a webcam.

In this case, the frames come when they're ready to come. Attempting to read too soon will produce nothing, reading too late will cause frames to be dropped. In this case, the ready flag can be used to determine whether or not a frame is ready for reading.

When streaming, you should still pay attention to last_start, but the value of next_start is only a guess.

Definition at line 150 of file movieVideoCursor.I.

void MovieVideoCursor::write_datagram ( BamWriter manager,
Datagram dg 
)
virtual

Writes the contents of this object to the datagram for shipping out to a Bam file.

Reimplemented from TypedWritable.

Reimplemented in FfmpegVideoCursor.

Definition at line 318 of file movieVideoCursor.cxx.

References TypedWritable::write_datagram(), and BamWriter::write_pointer().

Referenced by FfmpegVideoCursor::write_datagram().


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