TextReader.cpp

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// Copyright (c) 2008-2019 OpenShot Studios, LLC
//
// SPDX-License-Identifier: LGPL-3.0-or-later
 
// Require ImageMagick support
#ifdef USE_IMAGEMAGICK
 
#include "QtUtilities.h"
#include "MagickUtilities.h"
 
#include "TextReader.h"
#include "Exceptions.h"
#include "Frame.h"
 
using namespace openshot;
 
TextReader::TextReader() : width(1024), height(768), x_offset(0), y_offset(0), text(""), font("Arial"), size(10.0), text_color("#ffffff"), background_color("#000000"), is_open(false), gravity(GRAVITY_CENTER) {
 
    // Open and Close the reader, to populate its attributes (such as height, width, etc...)
    Open();
    Close();
}
 
TextReader::TextReader(int width, int height, int x_offset, int y_offset, GravityType gravity, std::string text, std::string font, double size, std::string text_color, std::string background_color)
: width(width), height(height), x_offset(x_offset), y_offset(y_offset), text(text), font(font), size(size), text_color(text_color), background_color(background_color), is_open(false), gravity(gravity)
{
    // Open and Close the reader, to populate its attributes (such as height, width, etc...)
    Open();
    Close();
}
 
void TextReader::SetTextBackgroundColor(std::string color) {
    text_background_color = color;
 
    // Open and Close the reader, to populate it's attributes (such as height, width, etc...) plus the text background color
    Open();
    Close();
}
 
// Open reader
void TextReader::Open()
{
    // Open reader if not already open
    if (!is_open)
    {
        // create image
        image = std::make_shared<Magick::Image>(
            Magick::Geometry(width,height), Magick::Color(background_color));
 
        // Give image a transparent background color
        image->backgroundColor(Magick::Color("none"));
 
        // Set gravity (map between OpenShot and ImageMagick)
        switch (gravity)
        {
        case GRAVITY_TOP_LEFT:
            lines.push_back(Magick::DrawableGravity(Magick::NorthWestGravity));
            break;
        case GRAVITY_TOP:
            lines.push_back(Magick::DrawableGravity(Magick::NorthGravity));
            break;
        case GRAVITY_TOP_RIGHT:
            lines.push_back(Magick::DrawableGravity(Magick::NorthEastGravity));
            break;
        case GRAVITY_LEFT:
            lines.push_back(Magick::DrawableGravity(Magick::WestGravity));
            break;
        case GRAVITY_CENTER:
            lines.push_back(Magick::DrawableGravity(Magick::CenterGravity));
            break;
        case GRAVITY_RIGHT:
            lines.push_back(Magick::DrawableGravity(Magick::EastGravity));
            break;
        case GRAVITY_BOTTOM_LEFT:
            lines.push_back(Magick::DrawableGravity(Magick::SouthWestGravity));
            break;
        case GRAVITY_BOTTOM:
            lines.push_back(Magick::DrawableGravity(Magick::SouthGravity));
            break;
        case GRAVITY_BOTTOM_RIGHT:
            lines.push_back(Magick::DrawableGravity(Magick::SouthEastGravity));
            break;
        }
 
        // Set stroke properties
        lines.push_back(Magick::DrawableStrokeColor(Magick::Color("none")));
        lines.push_back(Magick::DrawableStrokeWidth(0.0));
        lines.push_back(Magick::DrawableFillColor(text_color));
        lines.push_back(Magick::DrawableFont(font));
        lines.push_back(Magick::DrawablePointSize(size));
        lines.push_back(Magick::DrawableText(x_offset, y_offset, text));
 
        if (!text_background_color.empty()) {
            lines.push_back(Magick::DrawableTextUnderColor(Magick::Color(text_background_color)));
        }
 
        // Draw image
        image->draw(lines);
 
        // Update image properties
        info.has_audio = false;
        info.has_video = true;
        info.file_size = image->fileSize();
        info.vcodec = image->format();
        info.width = image->size().width();
        info.height = image->size().height();
        info.pixel_ratio.num = 1;
        info.pixel_ratio.den = 1;
        info.duration = 60 * 60 * 1;  // 1 hour duration
        info.fps.num = 30;
        info.fps.den = 1;
        info.video_timebase.num = 1;
        info.video_timebase.den = 30;
        info.video_length = round(info.duration * info.fps.ToDouble());
 
        // Calculate the DAR (display aspect ratio)
        Fraction size(info.width * info.pixel_ratio.num, info.height * info.pixel_ratio.den);
 
        // Reduce size fraction
        size.Reduce();
 
        // Set the ratio based on the reduced fraction
        info.display_ratio.num = size.num;
        info.display_ratio.den = size.den;
 
        // Mark as "open"
        is_open = true;
    }
}
 
// Close reader
void TextReader::Close()
{
    // Close all objects, if reader is 'open'
    if (is_open)
    {
        // Mark as "closed"
        is_open = false;
    }
}
 
// Get an openshot::Frame object for a specific frame number of this reader.
std::shared_ptr<Frame> TextReader::GetFrame(int64_t requested_frame)
{
    if (image)
    {
        // Create or get frame object
        auto image_frame = std::make_shared<Frame>(
            requested_frame,
            image->size().width(), image->size().height(),
            "#000000", 0, 2);
 
        // Add Image data to frame
        auto copy_image = std::make_shared<Magick::Image>(*image.get());
        copy_image->modifyImage(); // actually copy the image data to this object
        auto qimage = openshot::Magick2QImage(copy_image);
        image_frame->AddImage(qimage);
 
        // return frame object
        return image_frame;
    } else {
        // return empty frame
        auto image_frame = std::make_shared<Frame>(1, 640, 480, "#000000", 0, 2);
 
        // return frame object
        return image_frame;
    }
 
}
 
// Generate JSON string of this object
std::string TextReader::Json() const {
 
    // Return formatted string
    return JsonValue().toStyledString();
}
 
// Generate Json::Value for this object
Json::Value TextReader::JsonValue() const {
 
    // Create root json object
    Json::Value root = ReaderBase::JsonValue(); // get parent properties
    root["type"] = "TextReader";
    root["width"] = width;
    root["height"] = height;
    root["x_offset"] = x_offset;
    root["y_offset"] = y_offset;
    root["text"] = text;
    root["font"] = font;
    root["size"] = size;
    root["text_color"] = text_color;
    root["background_color"] = background_color;
    root["text_background_color"] = text_background_color;
    root["gravity"] = gravity;
 
    // return JsonValue
    return root;
}
 
// Load JSON string into this object
void TextReader::SetJson(const std::string value) {
    try
    {
        Json::Value root = openshot::stringToJson(value);
        // Set all values that match
        SetJsonValue(root);
    }
    catch (const std::exception& e)
    {
        // Error parsing JSON (or missing keys)
        throw InvalidJSON("JSON is invalid (missing keys or invalid data types)");
    }
}
 
// Load Json::Value into this object
void TextReader::SetJsonValue(const Json::Value root) {
 
    // Set parent data
    ReaderBase::SetJsonValue(root);
 
    // Set data from Json (if key is found)
    if (!root["width"].isNull())
        width = root["width"].asInt();
    if (!root["height"].isNull())
        height = root["height"].asInt();
    if (!root["x_offset"].isNull())
        x_offset = root["x_offset"].asInt();
    if (!root["y_offset"].isNull())
        y_offset = root["y_offset"].asInt();
    if (!root["text"].isNull())
        text = root["text"].asString();
    if (!root["font"].isNull())
        font = root["font"].asString();
    if (!root["size"].isNull())
        size = root["size"].asDouble();
    if (!root["text_color"].isNull())
        text_color = root["text_color"].asString();
    if (!root["background_color"].isNull())
        background_color = root["background_color"].asString();
    if (!root["text_background_color"].isNull())
        text_background_color = root["text_background_color"].asString();
    if (!root["gravity"].isNull())
        gravity = (GravityType) root["gravity"].asInt();
 
    // Re-Open path, and re-init everything (if needed)
    if (is_open)
    {
        Close();
        Open();
    }
}
 
#endif //USE_IMAGEMAGICK