OpenShot Library | libopenshot  0.2.7
QtTextReader.cpp
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1 /**
2  * @file
3  * @brief Source file for QtTextReader class
4  * @author Jonathan Thomas <jonathan@openshot.org>
5  * @author Sergei Kolesov (jediserg)
6  * @author Jeff Shillitto (jeffski)
7  *
8  * @ref License
9  */
10 
11 /* LICENSE
12  *
13  * Copyright (c) 2008-2019 OpenShot Studios, LLC
14  * <http://www.openshotstudios.com/>. This file is part of
15  * OpenShot Library (libopenshot), an open-source project dedicated to
16  * delivering high quality video editing and animation solutions to the
17  * world. For more information visit <http://www.openshot.org/>.
18  *
19  * OpenShot Library (libopenshot) is free software: you can redistribute it
20  * and/or modify it under the terms of the GNU Lesser General Public License
21  * as published by the Free Software Foundation, either version 3 of the
22  * License, or (at your option) any later version.
23  *
24  * OpenShot Library (libopenshot) is distributed in the hope that it will be
25  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
27  * GNU Lesser General Public License for more details.
28  *
29  * You should have received a copy of the GNU Lesser General Public License
30  * along with OpenShot Library. If not, see <http://www.gnu.org/licenses/>.
31  */
32 
33 #include "QtTextReader.h"
34 #include "Exceptions.h"
35 #include <QImage>
36 #include <QPainter>
37 
38 using namespace openshot;
39 
40 /// Default constructor (blank text)
41 QtTextReader::QtTextReader() : width(1024), height(768), x_offset(0), y_offset(0), text(""), font(QFont("Arial", 10)), text_color("#ffffff"), background_color("#000000"), is_open(false), gravity(GRAVITY_CENTER)
42 {
43  // Open and Close the reader, to populate it's attributes (such as height, width, etc...)
44  Open();
45  Close();
46 }
47 
48 QtTextReader::QtTextReader(int width, int height, int x_offset, int y_offset, GravityType gravity, std::string text, QFont font, std::string text_color, std::string background_color)
49 : width(width), height(height), x_offset(x_offset), y_offset(y_offset), text(text), font(font), text_color(text_color), background_color(background_color), is_open(false), gravity(gravity)
50 {
51  // Open and Close the reader, to populate it's attributes (such as height, width, etc...)
52  Open();
53  Close();
54 }
55 
56 void QtTextReader::SetTextBackgroundColor(std::string color) {
57  text_background_color = color;
58 
59  // Open and Close the reader, to populate it's attributes (such as height, width, etc...) plus the text background color
60  Open();
61  Close();
62 }
63 
64 // Open reader
66 {
67  // Open reader if not already open
68  if (!is_open)
69  {
70  // create image
71  image = std::make_shared<QImage>(width, height, QImage::Format_RGBA8888_Premultiplied);
72  image->fill(QColor(background_color.c_str()));
73 
74  QPainter painter;
75  if (!painter.begin(image.get())) {
76  return;
77  }
78 
79  // set background
80  if (!text_background_color.empty()) {
81  painter.setBackgroundMode(Qt::OpaqueMode);
82  painter.setBackground(QBrush(text_background_color.c_str()));
83  }
84 
85  // set font color
86  painter.setPen(QPen(text_color.c_str()));
87 
88  // set font
89  painter.setFont(font);
90 
91  // Set gravity (map between OpenShot and Qt)
92  int align_flag = 0;
93  switch (gravity)
94  {
95  case GRAVITY_TOP_LEFT:
96  align_flag = Qt::AlignLeft | Qt::AlignTop;
97  break;
98  case GRAVITY_TOP:
99  align_flag = Qt::AlignHCenter | Qt::AlignTop;
100  break;
101  case GRAVITY_TOP_RIGHT:
102  align_flag = Qt::AlignRight | Qt::AlignTop;
103  break;
104  case GRAVITY_LEFT:
105  align_flag = Qt::AlignVCenter | Qt::AlignLeft;
106  break;
107  case GRAVITY_CENTER:
108  align_flag = Qt::AlignCenter;
109  break;
110  case GRAVITY_RIGHT:
111  align_flag = Qt::AlignVCenter | Qt::AlignRight;
112  break;
113  case GRAVITY_BOTTOM_LEFT:
114  align_flag = Qt::AlignLeft | Qt::AlignBottom;
115  break;
116  case GRAVITY_BOTTOM:
117  align_flag = Qt::AlignHCenter | Qt::AlignBottom;
118  break;
120  align_flag = Qt::AlignRight | Qt::AlignBottom;
121  break;
122  }
123 
124  // Draw image
125  painter.drawText(x_offset, y_offset, width, height, align_flag, text.c_str());
126 
127  painter.end();
128 
129  // Update image properties
130  info.has_audio = false;
131  info.has_video = true;
132  info.file_size = 0;
133  info.vcodec = "QImage";
134  info.width = width;
135  info.height = height;
136  info.pixel_ratio.num = 1;
137  info.pixel_ratio.den = 1;
138  info.duration = 60 * 60 * 1; // 1 hour duration
139  info.fps.num = 30;
140  info.fps.den = 1;
141  info.video_timebase.num = 1;
142  info.video_timebase.den = 30;
144 
145  // Calculate the DAR (display aspect ratio)
147 
148  // Reduce size fraction
149  font_size.Reduce();
150 
151  // Set the ratio based on the reduced fraction
152  info.display_ratio.num = font_size.num;
153  info.display_ratio.den = font_size.den;
154 
155  // Mark as "open"
156  is_open = true;
157  }
158 }
159 
160 // Close reader
162 {
163  // Close all objects, if reader is 'open'
164  if (is_open)
165  {
166  // Mark as "closed"
167  is_open = false;
168 
169  // Delete the image
170  image.reset();
171 
172  info.vcodec = "";
173  info.acodec = "";
174  }
175 }
176 
177 // Get an openshot::Frame object for a specific frame number of this reader.
178 std::shared_ptr<Frame> QtTextReader::GetFrame(int64_t requested_frame)
179 {
180  if (image)
181  {
182  // Create or get frame object
183  auto image_frame = std::make_shared<Frame>(
184  requested_frame, image->size().width(), image->size().height(),
185  background_color, 0, 2);
186 
187  // Add Image data to frame
188  image_frame->AddImage(image);
189 
190  // return frame object
191  return image_frame;
192  } else {
193  // return empty frame
194  auto image_frame = std::make_shared<Frame>(1, 640, 480, background_color, 0, 2);
195 
196  // return frame object
197  return image_frame;
198  }
199 
200 }
201 
202 // Generate JSON string of this object
203 std::string QtTextReader::Json() const {
204 
205  // Return formatted string
206  return JsonValue().toStyledString();
207 }
208 
209 // Generate Json::Value for this object
210 Json::Value QtTextReader::JsonValue() const {
211 
212  // Create root json object
213  Json::Value root = ReaderBase::JsonValue(); // get parent properties
214  root["type"] = "QtTextReader";
215  root["width"] = width;
216  root["height"] = height;
217  root["x_offset"] = x_offset;
218  root["y_offset"] = y_offset;
219  root["text"] = text;
220  root["font"] = font.toString().toStdString();
221  root["text_color"] = text_color;
222  root["background_color"] = background_color;
223  root["text_background_color"] = text_background_color;
224  root["gravity"] = gravity;
225 
226  // return JsonValue
227  return root;
228 }
229 
230 // Load JSON string into this object
231 void QtTextReader::SetJson(const std::string value) {
232 
233  // Parse JSON string into JSON objects
234  try
235  {
236  const Json::Value root = openshot::stringToJson(value);
237  // Set all values that match
238  SetJsonValue(root);
239  }
240  catch (const std::exception& e)
241  {
242  // Error parsing JSON (or missing keys)
243  throw InvalidJSON("JSON is invalid (missing keys or invalid data types)");
244  }
245 }
246 
247 // Load Json::Value into this object
248 void QtTextReader::SetJsonValue(const Json::Value root) {
249 
250  // Set parent data
252 
253  // Set data from Json (if key is found)
254  if (!root["width"].isNull())
255  width = root["width"].asInt();
256  if (!root["height"].isNull())
257  height = root["height"].asInt();
258  if (!root["x_offset"].isNull())
259  x_offset = root["x_offset"].asInt();
260  if (!root["y_offset"].isNull())
261  y_offset = root["y_offset"].asInt();
262  if (!root["text"].isNull())
263  text = root["text"].asString();
264  if (!root["font"].isNull())
265  font.fromString(QString::fromStdString(root["font"].asString()));
266  if (!root["text_color"].isNull())
267  text_color = root["text_color"].asString();
268  if (!root["background_color"].isNull())
269  background_color = root["background_color"].asString();
270  if (!root["text_background_color"].isNull())
271  text_background_color = root["text_background_color"].asString();
272  if (!root["gravity"].isNull())
273  gravity = (GravityType) root["gravity"].asInt();
274 
275  // Re-Open path, and re-init everything (if needed)
276  if (is_open)
277  {
278  Close();
279  Open();
280  }
281 }
int num
Numerator for the fraction.
Definition: Fraction.h:50
Align clip to the right of its parent (middle aligned)
Definition: Enums.h:45
Header file for QtTextReader class.
Align clip to the bottom right of its parent.
Definition: Enums.h:48
int width
The width of the video (in pixesl)
Definition: ReaderBase.h:68
void SetTextBackgroundColor(std::string color)
float duration
Length of time (in seconds)
Definition: ReaderBase.h:65
double ToDouble() const
Return this fraction as a double (i.e. 1/2 = 0.5)
Definition: Fraction.cpp:59
std::shared_ptr< openshot::Frame > GetFrame(int64_t requested_frame) override
const Json::Value stringToJson(const std::string value)
Definition: Json.cpp:34
Json::Value JsonValue() const override
Generate Json::Value for this object.
bool has_video
Determines if this file has a video stream.
Definition: ReaderBase.h:62
std::string Json() const override
Generate JSON string of this object.
int64_t file_size
Size of file (in bytes)
Definition: ReaderBase.h:66
Align clip to the top right of its parent.
Definition: Enums.h:42
Align clip to the bottom left of its parent.
Definition: Enums.h:46
Header file for all Exception classes.
bool has_audio
Determines if this file has an audio stream.
Definition: ReaderBase.h:63
virtual Json::Value JsonValue() const =0
Generate Json::Value for this object.
Definition: ReaderBase.cpp:116
int64_t video_length
The number of frames in the video stream.
Definition: ReaderBase.h:75
int height
The height of the video (in pixels)
Definition: ReaderBase.h:67
Align clip to the bottom center of its parent.
Definition: Enums.h:47
Align clip to the top left of its parent.
Definition: Enums.h:40
openshot::Fraction video_timebase
The video timebase determines how long each frame stays on the screen.
Definition: ReaderBase.h:77
This class represents a fraction.
Definition: Fraction.h:48
Align clip to the left of its parent (middle aligned)
Definition: Enums.h:43
void SetJsonValue(const Json::Value root) override
Load Json::Value into this object.
virtual void SetJsonValue(const Json::Value root)=0
Load Json::Value into this object.
Definition: ReaderBase.cpp:171
openshot::ReaderInfo info
Information about the current media file.
Definition: ReaderBase.h:111
Align clip to the center of its parent (middle aligned)
Definition: Enums.h:44
std::string vcodec
The name of the video codec used to encode / decode the video stream.
Definition: ReaderBase.h:74
void Open() override
Open Reader - which is called by the constructor automatically.
This namespace is the default namespace for all code in the openshot library.
Definition: Compressor.h:46
void Close() override
Close Reader.
Exception for invalid JSON.
Definition: Exceptions.h:205
openshot::Fraction display_ratio
The ratio of width to height of the video stream (i.e. 640x480 has a ratio of 4/3) ...
Definition: ReaderBase.h:73
openshot::Fraction pixel_ratio
The pixel ratio of the video stream as a fraction (i.e. some pixels are not square) ...
Definition: ReaderBase.h:72
QtTextReader()
Default constructor (blank text)
void SetJson(const std::string value) override
Load JSON string into this object.
Align clip to the top center of its parent.
Definition: Enums.h:41
int den
Denominator for the fraction.
Definition: Fraction.h:51
openshot::Fraction fps
Frames per second, as a fraction (i.e. 24/1 = 24 fps)
Definition: ReaderBase.h:70
GravityType
This enumeration determines how clips are aligned to their parent container.
Definition: Enums.h:38
std::string acodec
The name of the audio codec used to encode / decode the video stream.
Definition: ReaderBase.h:80