Wave.cpp

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// Copyright (c) 2008-2019 OpenShot Studios, LLC
//
// SPDX-License-Identifier: LGPL-3.0-or-later
 
#include "Wave.h"
#include "Exceptions.h"
 
using namespace openshot;
 
Wave::Wave() : wavelength(0.06), amplitude(0.3), multiplier(0.2), shift_x(0.0), speed_y(0.2) {
    // Init effect properties
    init_effect_details();
}
 
// Default constructor
Wave::Wave(Keyframe wavelength, Keyframe amplitude, Keyframe multiplier, Keyframe shift_x, Keyframe speed_y)
        : wavelength(wavelength), amplitude(amplitude), multiplier(multiplier), shift_x(shift_x), speed_y(speed_y)
{
    // Init effect properties
    init_effect_details();
}
 
// Init effect settings
void Wave::init_effect_details()
{
    InitEffectInfo();
 
    info.class_name = "Wave";
    info.name = "Wave";
    info.description = "Distort the frame's image into a wave pattern.";
    info.has_audio = false;
    info.has_video = true;
 
}
 
// This method is required for all derived classes of EffectBase, and returns a
// modified openshot::Frame object
std::shared_ptr<openshot::Frame> Wave::GetFrame(std::shared_ptr<openshot::Frame> frame, int64_t frame_number)
{
    // Get the frame's image
    std::shared_ptr<QImage> frame_image = frame->GetImage();
 
    // Copy original pixels for reference, and get a writable pointer for editing
    QImage original = frame_image->copy();
    const unsigned char *original_pixels = original.constBits();
    unsigned char *pixels = frame_image->bits();
    int pixel_count = frame_image->width() * frame_image->height();
 
    // Get current keyframe values
    double time = frame_number;
    double wavelength_value = wavelength.GetValue(frame_number);
    double amplitude_value = amplitude.GetValue(frame_number);
    double multiplier_value = multiplier.GetValue(frame_number);
    double shift_x_value = shift_x.GetValue(frame_number);
    double speed_y_value = speed_y.GetValue(frame_number);
 
    // Loop through pixels
    #pragma omp parallel for
    for (int pixel = 0; pixel < pixel_count; ++pixel)
    {
        // Calculate pixel Y value
        int Y = pixel / frame_image->width();
 
        // Calculate wave pixel offsets
        float noiseVal = (100 + Y * 0.001) * multiplier_value;  // Time and time multiplier (to make the wave move)
        float noiseAmp = noiseVal * amplitude_value;  // Apply amplitude / height of the wave
        float waveformVal = sin((Y * wavelength_value) + (time * speed_y_value));  // Waveform algorithm on y-axis
        float waveVal = (waveformVal + shift_x_value) * noiseAmp;  // Shifts pixels on the x-axis
 
        int source_px = lround(pixel + waveVal);
        if (source_px < 0)
            source_px = 0;
        if (source_px >= pixel_count)
            source_px = pixel_count - 1;
 
        // Calculate source array location, and target array location, and copy the 4 color values
        memcpy(&pixels[pixel * 4], &original_pixels[source_px * 4], sizeof(char) * 4);
    }
 
    // return the modified frame
    return frame;
}
 
// Generate JSON string of this object
std::string Wave::Json() const {
 
    // Return formatted string
    return JsonValue().toStyledString();
}
 
// Generate Json::Value for this object
Json::Value Wave::JsonValue() const {
 
    // Create root json object
    Json::Value root = EffectBase::JsonValue(); // get parent properties
    root["type"] = info.class_name;
    root["wavelength"] = wavelength.JsonValue();
    root["amplitude"] = amplitude.JsonValue();
    root["multiplier"] = multiplier.JsonValue();
    root["shift_x"] = shift_x.JsonValue();
    root["speed_y"] = speed_y.JsonValue();
 
    // return JsonValue
    return root;
}
 
// Load JSON string into this object
void Wave::SetJson(const std::string value) {
 
    // Parse JSON string into JSON objects
    try
    {
        const 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 Wave::SetJsonValue(const Json::Value root) {
 
    // Set parent data
    EffectBase::SetJsonValue(root);
 
    // Set data from Json (if key is found)
    if (!root["wavelength"].isNull())
        wavelength.SetJsonValue(root["wavelength"]);
    if (!root["amplitude"].isNull())
        amplitude.SetJsonValue(root["amplitude"]);
    if (!root["multiplier"].isNull())
        multiplier.SetJsonValue(root["multiplier"]);
    if (!root["shift_x"].isNull())
        shift_x.SetJsonValue(root["shift_x"]);
    if (!root["speed_y"].isNull())
        speed_y.SetJsonValue(root["speed_y"]);
}
 
// Get all properties for a specific frame
std::string Wave::PropertiesJSON(int64_t requested_frame) const {
 
    // Generate JSON properties list
    Json::Value root = BasePropertiesJSON(requested_frame);
 
    // Keyframes
    root["wavelength"] = add_property_json("Wave length", wavelength.GetValue(requested_frame), "float", "", &wavelength, 0.0, 3.0, false, requested_frame);
    root["amplitude"] = add_property_json("Amplitude", amplitude.GetValue(requested_frame), "float", "", &amplitude, 0.0, 5.0, false, requested_frame);
    root["multiplier"] = add_property_json("Multiplier", multiplier.GetValue(requested_frame), "float", "", &multiplier, 0.0, 10.0, false, requested_frame);
    root["shift_x"] = add_property_json("X Shift", shift_x.GetValue(requested_frame), "float", "", &shift_x, 0.0, 1000.0, false, requested_frame);
    root["speed_y"] = add_property_json("Vertical speed", speed_y.GetValue(requested_frame), "float", "", &speed_y, 0.0, 300.0, false, requested_frame);
 
    // Return formatted string
    return root.toStyledString();
}