OpenShot Library | libopenshot  0.2.3
Timeline.h
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1 /**
2  * @file
3  * @brief Header file for Timeline class
4  * @author Jonathan Thomas <jonathan@openshot.org>
5  *
6  * @section LICENSE
7  *
8  * Copyright (c) 2008-2014 OpenShot Studios, LLC
9  * <http://www.openshotstudios.com/>. This file is part of
10  * OpenShot Library (libopenshot), an open-source project dedicated to
11  * delivering high quality video editing and animation solutions to the
12  * world. For more information visit <http://www.openshot.org/>.
13  *
14  * OpenShot Library (libopenshot) is free software: you can redistribute it
15  * and/or modify it under the terms of the GNU Lesser General Public License
16  * as published by the Free Software Foundation, either version 3 of the
17  * License, or (at your option) any later version.
18  *
19  * OpenShot Library (libopenshot) is distributed in the hope that it will be
20  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22  * GNU Lesser General Public License for more details.
23  *
24  * You should have received a copy of the GNU Lesser General Public License
25  * along with OpenShot Library. If not, see <http://www.gnu.org/licenses/>.
26  */
27 
28 #ifndef OPENSHOT_TIMELINE_H
29 #define OPENSHOT_TIMELINE_H
30 
31 #include <list>
32 #include <memory>
33 #include <QtGui/QImage>
34 #include <QtGui/QPainter>
35 #include "CacheBase.h"
36 #include "CacheDisk.h"
37 #include "CacheMemory.h"
38 #include "Color.h"
39 #include "Clip.h"
40 #include "CrashHandler.h"
41 #include "Point.h"
42 #include "EffectBase.h"
43 #include "Effects.h"
44 #include "EffectInfo.h"
45 #include "Fraction.h"
46 #include "Frame.h"
47 #include "FrameMapper.h"
48 #include "KeyFrame.h"
49 #include "OpenMPUtilities.h"
50 #include "ReaderBase.h"
51 #include "Settings.h"
52 
53 using namespace std;
54 using namespace openshot;
55 
56 namespace openshot {
57 
58  /// Comparison method for sorting clip pointers (by Layer and then Position). Clips are sorted
59  /// from lowest layer to top layer (since that is the sequence they need to be combined), and then
60  /// by position (left to right).
61  struct CompareClips{
62  bool operator()( Clip* lhs, Clip* rhs){
63  if( lhs->Layer() < rhs->Layer() ) return true;
64  if( lhs->Layer() == rhs->Layer() && lhs->Position() <= rhs->Position() ) return true;
65  return false;
66  }};
67 
68  /// Comparison method for sorting effect pointers (by Position, Layer, and Order). Effects are sorted
69  /// from lowest layer to top layer (since that is sequence clips are combined), and then by
70  /// position, and then by effect order.
72  bool operator()( EffectBase* lhs, EffectBase* rhs){
73  if( lhs->Layer() < rhs->Layer() ) return true;
74  if( lhs->Layer() == rhs->Layer() && lhs->Position() < rhs->Position() ) return true;
75  if( lhs->Layer() == rhs->Layer() && lhs->Position() == rhs->Position() && lhs->Order() > rhs->Order() ) return true;
76  return false;
77  }};
78 
79  /**
80  * @brief This class represents a timeline
81  *
82  * The timeline is one of the <b>most important</b> features of a video editor, and controls all
83  * aspects of how video, image, and audio clips are combined together, and how the final
84  * video output will be rendered. It has a collection of layers and clips, that arrange,
85  * sequence, and generate the final video output.
86  *
87  * The <b>following graphic</b> displays a timeline, and how clips can be arranged, scaled, and layered together. It
88  * also demonstrates how the viewport can be scaled smaller than the canvas, which can be used to zoom and pan around the
89  * canvas (i.e. pan & scan).
90  * \image html /doc/images/Timeline_Layers.png
91  *
92  * The <b>following graphic</b> displays how the playhead determines which frames to combine and layer.
93  * \image html /doc/images/Playhead.png
94  *
95  * Lets take a look at what the code looks like:
96  * @code
97  * // Create a Timeline
98  * Timeline t(1280, // width
99  * 720, // height
100  * Fraction(25,1), // framerate
101  * 44100, // sample rate
102  * 2 // channels
103  * );
104  *
105  * // Create some clips
106  * Clip c1(new ImageReader("MyAwesomeLogo.jpeg"));
107  * Clip c2(new FFmpegReader("BackgroundVideo.webm"));
108  *
109  * // CLIP 1 (logo) - Set some clip properties (with Keyframes)
110  * c1.Position(0.0); // Set the position or location (in seconds) on the timeline
111  * c1.gravity = GRAVITY_LEFT; // Set the alignment / gravity of the clip (position on the screen)
112  * c1.scale = SCALE_CROP; // Set the scale mode (how the image is resized to fill the screen)
113  * c1.Layer(1); // Set the layer of the timeline (higher layers cover up images of lower layers)
114  * c1.Start(0.0); // Set the starting position of the video (trim the left side of the video)
115  * c1.End(16.0); // Set the ending position of the video (trim the right side of the video)
116  * c1.alpha.AddPoint(1, 0.0); // Set the alpha to transparent on frame #1
117  * c1.alpha.AddPoint(500, 0.0); // Keep the alpha transparent until frame #500
118  * c1.alpha.AddPoint(565, 1.0); // Animate the alpha from transparent to visible (between frame #501 and #565)
119  *
120  * // CLIP 2 (background video) - Set some clip properties (with Keyframes)
121  * c2.Position(0.0); // Set the position or location (in seconds) on the timeline
122  * c2.Start(10.0); // Set the starting position of the video (trim the left side of the video)
123  * c2.Layer(0); // Set the layer of the timeline (higher layers cover up images of lower layers)
124  * c2.alpha.AddPoint(1, 1.0); // Set the alpha to visible on frame #1
125  * c2.alpha.AddPoint(150, 0.0); // Animate the alpha to transparent (between frame 2 and frame #150)
126  * c2.alpha.AddPoint(360, 0.0, LINEAR); // Keep the alpha transparent until frame #360
127  * c2.alpha.AddPoint(384, 1.0); // Animate the alpha to visible (between frame #360 and frame #384)
128  *
129  * // Add clips to timeline
130  * t.AddClip(&c1);
131  * t.AddClip(&c2);
132  *
133  * // Open the timeline reader
134  * t.Open();
135  *
136  * // Get frame number 1 from the timeline (This will generate a new frame, made up from the previous clips and settings)
137  * std::shared_ptr<Frame> f = t.GetFrame(1);
138  *
139  * // Now that we have an openshot::Frame object, lets have some fun!
140  * f->Display(); // Display the frame on the screen
141  *
142  * // Close the timeline reader
143  * t.Close();
144  * @endcode
145  */
146  class Timeline : public ReaderBase {
147  private:
148  bool is_open; ///<Is Timeline Open?
149  bool auto_map_clips; ///< Auto map framerates and sample rates to all clips
150  list<Clip*> clips; ///<List of clips on this timeline
151  list<Clip*> closing_clips; ///<List of clips that need to be closed
152  map<Clip*, Clip*> open_clips; ///<List of 'opened' clips on this timeline
153  list<EffectBase*> effects; ///<List of clips on this timeline
154  CacheBase *final_cache; ///<Final cache of timeline frames
155 
156  /// Process a new layer of video or audio
157  void add_layer(std::shared_ptr<Frame> new_frame, Clip* source_clip, int64_t clip_frame_number, int64_t timeline_frame_number, bool is_top_clip, float max_volume);
158 
159  /// Apply a FrameMapper to a clip which matches the settings of this timeline
160  void apply_mapper_to_clip(Clip* clip);
161 
162  /// Apply JSON Diffs to various objects contained in this timeline
163  void apply_json_to_clips(Json::Value change); ///<Apply JSON diff to clips
164  void apply_json_to_effects(Json::Value change); ///< Apply JSON diff to effects
165  void apply_json_to_effects(Json::Value change, EffectBase* existing_effect); ///<Apply JSON diff to a specific effect
166  void apply_json_to_timeline(Json::Value change); ///<Apply JSON diff to timeline properties
167 
168  /// Calculate time of a frame number, based on a framerate
169  double calculate_time(int64_t number, Fraction rate);
170 
171  /// Find intersecting (or non-intersecting) openshot::Clip objects
172  ///
173  /// @returns A list of openshot::Clip objects
174  /// @param requested_frame The frame number that is requested.
175  /// @param number_of_frames The number of frames to check
176  /// @param include Include or Exclude intersecting clips
177  vector<Clip*> find_intersecting_clips(int64_t requested_frame, int number_of_frames, bool include);
178 
179  /// Get or generate a blank frame
180  std::shared_ptr<Frame> GetOrCreateFrame(Clip* clip, int64_t number);
181 
182  /// Apply effects to the source frame (if any)
183  std::shared_ptr<Frame> apply_effects(std::shared_ptr<Frame> frame, int64_t timeline_frame_number, int layer);
184 
185  /// Compare 2 floating point numbers for equality
186  bool isEqual(double a, double b);
187 
188  /// Sort clips by position on the timeline
189  void sort_clips();
190 
191  /// Sort effects by position on the timeline
192  void sort_effects();
193 
194  /// Update the list of 'opened' clips
195  void update_open_clips(Clip *clip, bool does_clip_intersect);
196 
197  public:
198 
199  /// @brief Default Constructor for the timeline (which sets the canvas width and height and FPS)
200  /// @param width The width of the timeline (and thus, the generated openshot::Frame objects)
201  /// @param height The height of the timeline (and thus, the generated openshot::Frame objects)
202  /// @param fps The frames rate of the timeline
203  /// @param sample_rate The sample rate of the timeline's audio
204  /// @param channels The number of audio channels of the timeline
205  /// @param channel_layout The channel layout (i.e. mono, stereo, 3 point surround, etc...)
206  Timeline(int width, int height, Fraction fps, int sample_rate, int channels, ChannelLayout channel_layout);
207 
208  /// @brief Add an openshot::Clip to the timeline
209  /// @param clip Add an openshot::Clip to the timeline. A clip can contain any type of Reader.
210  void AddClip(Clip* clip);
211 
212  /// @brief Add an effect to the timeline
213  /// @param effect Add an effect to the timeline. An effect can modify the audio or video of an openshot::Frame.
214  void AddEffect(EffectBase* effect);
215 
216  /// Apply the timeline's framerate and samplerate to all clips
217  void ApplyMapperToClips();
218 
219  /// Determine if clips are automatically mapped to the timeline's framerate and samplerate
220  bool AutoMapClips() { return auto_map_clips; };
221 
222  /// @brief Automatically map all clips to the timeline's framerate and samplerate
223  void AutoMapClips(bool auto_map) { auto_map_clips = auto_map; };
224 
225  /// Clear all cache for this timeline instance, and all clips, mappers, and readers under it
226  void ClearAllCache();
227 
228  /// Return a list of clips on the timeline
229  list<Clip*> Clips() { return clips; };
230 
231  /// Close the timeline reader (and any resources it was consuming)
232  void Close();
233 
234  /// Return the list of effects on the timeline
235  list<EffectBase*> Effects() { return effects; };
236 
237  /// Get the cache object used by this reader
238  CacheBase* GetCache() { return final_cache; };
239 
240  /// Get the cache object used by this reader
241  void SetCache(CacheBase* new_cache);
242 
243  /// Get an openshot::Frame object for a specific frame number of this timeline.
244  ///
245  /// @returns The requested frame (containing the image)
246  /// @param requested_frame The frame number that is requested.
247  std::shared_ptr<Frame> GetFrame(int64_t requested_frame);
248 
249  // Curves for the viewport
250  Keyframe viewport_scale; ///<Curve representing the scale of the viewport (0 to 100)
251  Keyframe viewport_x; ///<Curve representing the x coordinate for the viewport
252  Keyframe viewport_y; ///<Curve representing the y coordinate for the viewport
253 
254  // Background color
255  Color color; ///<Background color of timeline canvas
256 
257  /// Determine if reader is open or closed
258  bool IsOpen() { return is_open; };
259 
260  /// Return the type name of the class
261  string Name() { return "Timeline"; };
262 
263  /// Get and Set JSON methods
264  string Json(); ///< Generate JSON string of this object
265  void SetJson(string value); ///< Load JSON string into this object
266  Json::Value JsonValue(); ///< Generate Json::JsonValue for this object
267  void SetJsonValue(Json::Value root); ///< Load Json::JsonValue into this object
268 
269  /// Set Max Image Size (used for performance optimization). Convenience function for setting
270  /// Settings::Instance()->MAX_WIDTH and Settings::Instance()->MAX_HEIGHT.
271  void SetMaxSize(int width, int height);
272 
273  /// @brief Apply a special formatted JSON object, which represents a change to the timeline (add, update, delete)
274  /// This is primarily designed to keep the timeline (and its child objects... such as clips and effects) in sync
275  /// with another application... such as OpenShot Video Editor (http://www.openshot.org).
276  /// @param value A JSON string containing a key, value, and type of change.
277  void ApplyJsonDiff(string value);
278 
279  /// Open the reader (and start consuming resources)
280  void Open();
281 
282  /// @brief Remove an openshot::Clip from the timeline
283  /// @param clip Remove an openshot::Clip from the timeline.
284  void RemoveClip(Clip* clip);
285 
286  /// @brief Remove an effect from the timeline
287  /// @param effect Remove an effect from the timeline.
288  void RemoveEffect(EffectBase* effect);
289  };
290 
291 
292 }
293 
294 #endif
CacheBase * GetCache()
Get the cache object used by this reader.
Definition: Timeline.h:238
Header file for Fraction class.
This abstract class is the base class, used by all effects in libopenshot.
Definition: EffectBase.h:66
Keyframe viewport_scale
Curve representing the scale of the viewport (0 to 100)
Definition: Timeline.h:250
Header file for ReaderBase class.
bool AutoMapClips()
Determine if clips are automatically mapped to the timeline's framerate and samplerate.
Definition: Timeline.h:220
Header file for OpenMPUtilities (set some common macros)
Header file for Point class.
This header includes all commonly used effects for libopenshot, for ease-of-use.
Keyframe viewport_y
Curve representing the y coordinate for the viewport.
Definition: Timeline.h:252
This abstract class is the base class, used by all readers in libopenshot.
Definition: ReaderBase.h:97
int Layer()
Get layer of clip on timeline (lower number is covered by higher numbers)
Definition: ClipBase.h:82
Header file for the Keyframe class.
Header file for CacheMemory class.
Header file for CacheBase class.
This class represents a clip (used to arrange readers on the timeline)
Definition: Clip.h:100
Header file for Frame class.
Header file for Clip class.
float Position()
Get position on timeline (in seconds)
Definition: ClipBase.h:81
bool operator()(Clip *lhs, Clip *rhs)
Definition: Timeline.h:62
This class represents a fraction.
Definition: Fraction.h:42
Header file for the FrameMapper class.
All cache managers in libopenshot are based on this CacheBase class.
Definition: CacheBase.h:45
ChannelLayout
This enumeration determines the audio channel layout (such as stereo, mono, 5 point surround...
Header file for global Settings class.
Header file for Color class.
void AutoMapClips(bool auto_map)
Automatically map all clips to the timeline's framerate and samplerate.
Definition: Timeline.h:223
bool IsOpen()
Determine if reader is open or closed.
Definition: Timeline.h:258
This class represents a color (used on the timeline and clips)
Definition: Color.h:42
Header file for EffectBase class.
Keyframe viewport_x
Curve representing the x coordinate for the viewport.
Definition: Timeline.h:251
Header file for CacheDisk class.
Header file for CrashHandler class.
Color color
Background color of timeline canvas.
Definition: Timeline.h:255
string Name()
Return the type name of the class.
Definition: Timeline.h:261
list< EffectBase * > Effects()
Return the list of effects on the timeline.
Definition: Timeline.h:235
list< Clip * > Clips()
Return a list of clips on the timeline.
Definition: Timeline.h:229
Header file for the EffectInfo class.
A Keyframe is a collection of Point instances, which is used to vary a number or property over time...
Definition: KeyFrame.h:64
int Order()
Get the order that this effect should be executed.
Definition: EffectBase.h:104
bool operator()(EffectBase *lhs, EffectBase *rhs)
Definition: Timeline.h:72
This class represents a timeline.
Definition: Timeline.h:146