OpenShot Library | libopenshot  0.2.6
ImageReader.h
Go to the documentation of this file.
1 /**
2  * @file
3  * @brief Header file for ImageReader class
4  * @author Jonathan Thomas <jonathan@openshot.org>
5  *
6  * @ref License
7  */
8 
9 /* LICENSE
10  *
11  * Copyright (c) 2008-2019 OpenShot Studios, LLC
12  * <http://www.openshotstudios.com/>. This file is part of
13  * OpenShot Library (libopenshot), an open-source project dedicated to
14  * delivering high quality video editing and animation solutions to the
15  * world. For more information visit <http://www.openshot.org/>.
16  *
17  * OpenShot Library (libopenshot) is free software: you can redistribute it
18  * and/or modify it under the terms of the GNU Lesser General Public License
19  * as published by the Free Software Foundation, either version 3 of the
20  * License, or (at your option) any later version.
21  *
22  * OpenShot Library (libopenshot) is distributed in the hope that it will be
23  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
24  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
25  * GNU Lesser General Public License for more details.
26  *
27  * You should have received a copy of the GNU Lesser General Public License
28  * along with OpenShot Library. If not, see <http://www.gnu.org/licenses/>.
29  */
30 
31 #ifndef OPENSHOT_IMAGE_READER_H
32 #define OPENSHOT_IMAGE_READER_H
33 
34 // Require ImageMagick support
35 #ifdef USE_IMAGEMAGICK
36 
37 #include "ReaderBase.h"
38 
39 #include <cmath>
40 #include <ctime>
41 #include <iostream>
42 #include <omp.h>
43 #include <stdio.h>
44 #include <memory>
45 #include "CacheMemory.h"
46 
47 #include "MagickUtilities.h"
48 
49 namespace openshot
50 {
51  // Forward decls
52  class CacheBase;
53 
54  /**
55  * @brief This class uses the ImageMagick++ libraries, to open image files, and return
56  * openshot::Frame objects containing the image.
57  *
58  * @code
59  * // Create a reader for a video
60  * ImageReader r("MyAwesomeImage.jpeg");
61  * r.Open(); // Open the reader
62  *
63  * // Get frame number 1 from the video
64  * std::shared_ptr<Frame> f = r.GetFrame(1);
65  *
66  * // Now that we have an openshot::Frame object, lets have some fun!
67  * f->Display(); // Display the frame on the screen
68  *
69  * // Close the reader
70  * r.Close();
71  * @endcode
72  */
73  class ImageReader : public ReaderBase
74  {
75  private:
76  std::string path;
77  std::shared_ptr<Magick::Image> image;
78  bool is_open;
79 
80  public:
81  /// @brief Constructor for ImageReader.
82  ///
83  /// Opens the media file to inspect its properties and loads frame 1,
84  /// iff inspect_reader == true (the default). Pass a false value in
85  /// the optional parameter to defer this initial Open()/Close() cycle.
86  ///
87  /// When not inspecting the media file, it's much faster, and useful
88  /// when you are inflating the object using JSON after instantiation.
89  ImageReader(const std::string& path, bool inspect_reader=true);
90 
91  /// Close File
92  void Close() override;
93 
94  /// Get the cache object used by this reader (always returns NULL for this object)
95  CacheBase* GetCache() override { return NULL; };
96 
97  /// Get an openshot::Frame object for a specific frame number of this reader. All numbers
98  /// return the same Frame, since they all share the same image data.
99  ///
100  /// @returns The requested frame (containing the image)
101  /// @param requested_frame The frame number that is requested.
102  std::shared_ptr<Frame> GetFrame(int64_t requested_frame) override;
103 
104  /// Determine if reader is open or closed
105  bool IsOpen() override { return is_open; };
106 
107  /// Return the type name of the class
108  std::string Name() override { return "ImageReader"; };
109 
110  // Get and Set JSON methods
111  std::string Json() const override; ///< Generate JSON string of this object
112  void SetJson(const std::string value) override; ///< Load JSON string into this object
113  Json::Value JsonValue() const override; ///< Generate Json::Value for this object
114  void SetJsonValue(const Json::Value root) override; ///< Load Json::Value into this object
115 
116  /// Open File - which is called by the constructor automatically
117  void Open() override;
118  };
119 
120 }
121 
122 #endif //USE_IMAGEMAGICK
123 #endif //OPENSHOT_IMAGE_READER_H
void SetJsonValue(const Json::Value root) override
Load Json::Value into this object.
void Close() override
Close File.
Header file for ReaderBase class.
std::shared_ptr< Frame > GetFrame(int64_t requested_frame) override
bool IsOpen() override
Determine if reader is open or closed.
Definition: ImageReader.h:105
Header file for MagickUtilities (IM6/IM7 compatibility overlay)
CacheBase * GetCache() override
Get the cache object used by this reader (always returns NULL for this object)
Definition: ImageReader.h:95
void SetJson(const std::string value) override
Load JSON string into this object.
This abstract class is the base class, used by all readers in libopenshot.
Definition: ReaderBase.h:97
Header file for CacheMemory class.
This class uses the ImageMagick++ libraries, to open image files, and return openshot::Frame objects ...
Definition: ImageReader.h:73
std::string Name() override
Return the type name of the class.
Definition: ImageReader.h:108
All cache managers in libopenshot are based on this CacheBase class.
Definition: CacheBase.h:48
void Open() override
Open File - which is called by the constructor automatically.
Definition: ImageReader.cpp:49
Json::Value JsonValue() const override
Generate Json::Value for this object.
This namespace is the default namespace for all code in the openshot library.
Definition: Compressor.h:46
ImageReader(const std::string &path, bool inspect_reader=true)
Constructor for ImageReader.
Definition: ImageReader.cpp:39
std::string Json() const override
Generate JSON string of this object.