DummyReader.cpp

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/**
 * @file
 * @brief Source file for DummyReader class
 * @author Jonathan Thomas <jonathan@openshot.org>
 *
 * @section LICENSE
 *
 * Copyright (c) 2008-2014 OpenShot Studios, LLC
 * <http://www.openshotstudios.com/>. This file is part of
 * OpenShot Library (libopenshot), an open-source project dedicated to
 * delivering high quality video editing and animation solutions to the
 * world. For more information visit <http://www.openshot.org/>.
 *
 * OpenShot Library (libopenshot) is free software: you can redistribute it
 * and/or modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * OpenShot Library (libopenshot) is distributed in the hope that it will be
 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with OpenShot Library. If not, see <http://www.gnu.org/licenses/>.
 */

#include "../include/DummyReader.h"

using namespace openshot;

// Blank constructor for DummyReader, with default settings.
DummyReader::DummyReader() {

        // Call actual constructor with default values
        DummyReader(Fraction(24,1), 1280, 768, 44100, 2, 30.0);
}

// Constructor for DummyReader.  Pass a framerate and samplerate.
DummyReader::DummyReader(Fraction fps, int width, int height, int sample_rate, int channels, float duration) {

        // Set key info settings
        info.has_audio = false;
        info.has_video = true;
        info.file_size = width * height * sizeof(int);
        info.vcodec = "raw";
        info.fps = fps;
        info.width = width;
        info.height = height;
        info.sample_rate = sample_rate;
        info.channels = channels;
        info.duration = duration;
        info.video_length = duration * fps.ToFloat();
        info.pixel_ratio.num = 1;
        info.pixel_ratio.den = 1;
        info.video_timebase = fps.Reciprocal();
        info.acodec = "raw";

        // 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;

        // Open and Close the reader, to populate it's attributes (such as height, width, etc...)
        Open();
        Close();
}

// Open image file
void DummyReader::Open() throw(InvalidFile)
{
        // Open reader if not already open
        if (!is_open)
        {
                // Create or get frame object
                image_frame = tr1::shared_ptr<Frame>(new Frame(1, info.width, info.height, "#000000", info.sample_rate, info.channels));

                // Mark as "open"
                is_open = true;
        }
}

// Close image file
void DummyReader::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.
tr1::shared_ptr<Frame> DummyReader::GetFrame(long int requested_frame) throw(ReaderClosed)
{
        // Check for open reader (or throw exception)
        if (!is_open)
                throw ReaderClosed("The ImageReader is closed.  Call Open() before calling this method.", "dummy");

        if (image_frame)
        {
                // Create a scoped lock, allowing only a single thread to run the following code at one time
                const GenericScopedLock<CriticalSection> lock(getFrameCriticalSection);

                // Always return same frame (regardless of which frame number was requested)
                image_frame->number = requested_frame;
                return image_frame;
        }
        else
                // no frame loaded
                throw InvalidFile("No frame could be created from this type of file.", "dummy");
}

// Generate JSON string of this object
string DummyReader::Json() {

        // Return formatted string
        return JsonValue().toStyledString();
}

// Generate Json::JsonValue for this object
Json::Value DummyReader::JsonValue() {

        // Create root json object
        Json::Value root = ReaderBase::JsonValue(); // get parent properties
        root["type"] = "DummyReader";

        // return JsonValue
        return root;
}

// Load JSON string into this object
void DummyReader::SetJson(string value) throw(InvalidJSON) {

        // Parse JSON string into JSON objects
        Json::Value root;
        Json::Reader reader;
        bool success = reader.parse( value, root );
        if (!success)
                // Raise exception
                throw InvalidJSON("JSON could not be parsed (or is invalid)", "");

        try
        {
                // Set all values that match
                SetJsonValue(root);
        }
        catch (exception e)
        {
                // Error parsing JSON (or missing keys)
                throw InvalidJSON("JSON is invalid (missing keys or invalid data types)", "");
        }
}

// Load Json::JsonValue into this object
void DummyReader::SetJsonValue(Json::Value root) throw(InvalidFile) {

        // Set parent data
        ReaderBase::SetJsonValue(root);

}