OpenShot Library | libopenshot  0.2.7
ImageWriter.h
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1 /**
2  * @file
3  * @brief Header file for ImageWriter class
4  * @author Jonathan Thomas <jonathan@openshot.org>, Fabrice Bellard
5  *
6  * @ref License
7  */
8 
9 /* LICENSE
10  *
11  * Copyright (c) 2008-2019 OpenShot Studios, LLC, Fabrice Bellard
12  * (http://www.openshotstudios.com). This file is part of
13  * OpenShot Library (http://www.openshot.org), an open-source project
14  * dedicated to delivering high quality video editing and animation solutions
15  * to the world.
16  *
17  * This file is originally based on the Libavformat API example, and then modified
18  * by the libopenshot project.
19  *
20  * OpenShot Library is free software: you can redistribute it and/or modify
21  * it under the terms of the GNU General Public License as published by
22  * the Free Software Foundation, either version 3 of the License, or
23  * (at your option) any later version.
24  * * OpenShot Library (libopenshot) is free software: you can redistribute it
25  * and/or modify it under the terms of the GNU Lesser General Public License
26  * as published by the Free Software Foundation, either version 3 of the
27  * License, or (at your option) any later version.
28  *
29  * OpenShot Library (libopenshot) is distributed in the hope that it will be
30  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
31  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
32  * GNU Lesser General Public License for more details.
33  *
34  * You should have received a copy of the GNU Lesser General Public License
35  * along with OpenShot Library. If not, see <http://www.gnu.org/licenses/>.
36  */
37 
38 #ifndef OPENSHOT_IMAGE_WRITER_H
39 #define OPENSHOT_IMAGE_WRITER_H
40 
41 #ifdef USE_IMAGEMAGICK
42 
43 #include "ReaderBase.h"
44 #include "WriterBase.h"
45 
46 #include <string>
47 #include <vector>
48 #include "CacheMemory.h"
49 #include "Exceptions.h"
50 #include "Fraction.h"
51 
52 #include "OpenMPUtilities.h"
53 #include "MagickUtilities.h"
54 
55 namespace openshot
56 {
57 
58  /**
59  * @brief This class uses the ImageMagick library to write image files (including animated GIFs)
60  *
61  * All image formats supported by ImageMagick are supported by this class.
62  *
63  * @code
64  * // Create a reader for a video
65  * FFmpegReader r("MyAwesomeVideo.webm");
66  * r.Open(); // Open the reader
67  *
68  * // Create a writer (which will create an animated GIF file)
69  * ImageWriter w("/home/jonathan/NewAnimation.gif");
70  *
71  * // Set the image output settings (format, fps, width, height, quality, loops, combine)
72  * w.SetVideoOptions("GIF", r.info.fps, r.info.width, r.info.height, 70, 1, true);
73  *
74  * // Open the writer
75  * w.Open();
76  *
77  * // Write the 1st 30 frames from the reader
78  * w.WriteFrame(&r, 1, 30);
79  *
80  * // Close the reader & writer
81  * w.Close();
82  * r.Close();
83  * @endcode
84  */
85  class ImageWriter : public WriterBase
86  {
87  private:
88  std::string path;
89  int cache_size;
90  bool is_open;
91  int64_t write_video_count;
92  std::vector<Magick::Image> frames;
93  int image_quality;
94  int number_of_loops;
95  bool combine_frames;
96 
97  std::shared_ptr<Frame> last_frame;
98 
99  public:
100 
101  /// @brief Constructor for ImageWriter. Throws one of the following exceptions.
102  /// @param path The path of the file you want to create
103  ImageWriter(std::string path);
104 
105  /// @brief Close the writer and encode/output final image to the disk. This is a requirement of ImageMagick,
106  /// which writes all frames of a multi-frame image at one time.
107  void Close();
108 
109  /// @brief Get the cache size
110  int GetCacheSize() { return cache_size; };
111 
112  /// Determine if writer is open or closed
113  bool IsOpen() { return is_open; };
114 
115  /// Open writer
116  void Open();
117 
118  /// @brief Set the cache size (number of frames to queue before writing)
119  /// @param new_size Number of frames to queue before writing
120  void SetCacheSize(int new_size) { cache_size = new_size; };
121 
122  /// @brief Set the video export options
123  /// @param format The image format (such as GIF)
124  /// @param fps Frames per second of the image (used on certain multi-frame image formats, such as GIF)
125  /// @param width Width in pixels of image
126  /// @param height Height in pixels of image
127  /// @param quality Quality of image (0 to 100, 70 is default)
128  /// @param loops Number of times to repeat the image (used on certain multi-frame image formats, such as GIF)
129  /// @param combine Combine frames into a single image (if possible), or save each frame as its own image
130  void SetVideoOptions(std::string format, Fraction fps, int width, int height,
131  int quality, int loops, bool combine);
132 
133  /// @brief Add a frame to the stack waiting to be encoded.
134  /// @param frame The openshot::Frame object to write to this image
135  void WriteFrame(std::shared_ptr<Frame> frame);
136 
137  /// @brief Write a block of frames from a reader
138  /// @param reader A openshot::ReaderBase object which will provide frames to be written
139  /// @param start The starting frame number of the reader
140  /// @param length The number of frames to write
141  void WriteFrame(ReaderBase* reader, int64_t start, int64_t length);
142 
143  };
144 
145 }
146 
147 #endif //USE_IMAGEMAGICK
148 #endif //OPENSHOT_IMAGE_WRITER_H
Header file for CacheMemory class.
Header file for all Exception classes.
Header file for Fraction class.
Header file for MagickUtilities (IM6/IM7 compatibility overlay)
Header file for OpenMPUtilities (set some common macros)
Header file for ReaderBase class.
Header file for WriterBase class.
This class represents a fraction.
Definition: Fraction.h:48
This class uses the ImageMagick library to write image files (including animated GIFs)
Definition: ImageWriter.h:86
int GetCacheSize()
Get the cache size.
Definition: ImageWriter.h:110
void Close()
Close the writer and encode/output final image to the disk. This is a requirement of ImageMagick,...
ImageWriter(std::string path)
Constructor for ImageWriter. Throws one of the following exceptions.
Definition: ImageWriter.cpp:42
void SetVideoOptions(std::string format, Fraction fps, int width, int height, int quality, int loops, bool combine)
Set the video export options.
Definition: ImageWriter.cpp:52
void WriteFrame(std::shared_ptr< Frame > frame)
Add a frame to the stack waiting to be encoded.
Definition: ImageWriter.cpp:96
void Open()
Open writer.
Definition: ImageWriter.cpp:90
bool IsOpen()
Determine if writer is open or closed.
Definition: ImageWriter.h:113
void SetCacheSize(int new_size)
Set the cache size (number of frames to queue before writing)
Definition: ImageWriter.h:120
This abstract class is the base class, used by all readers in libopenshot.
Definition: ReaderBase.h:98
This abstract class is the base class, used by writers. Writers are types of classes that encode vide...
Definition: WriterBase.h:88
This namespace is the default namespace for all code in the openshot library.
Definition: Compressor.h:47