/** * @file * @brief Source file for Clip class * @author Jonathan Thomas * * @section LICENSE * * Copyright (c) 2008-2014 OpenShot Studios, LLC * . 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 . * * 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 . */ #include "../include/Clip.h" using namespace openshot; // Init default settings for a clip void Clip::init_settings() { // Init clip settings Position(0.0); Layer(0); Start(0.0); End(0.0); gravity = GRAVITY_CENTER; scale = SCALE_FIT; anchor = ANCHOR_CANVAS; waveform = false; previous_properties = ""; // Init scale curves scale_x = Keyframe(1.0); scale_y = Keyframe(1.0); // Init location curves location_x = Keyframe(0.0); location_y = Keyframe(0.0); // Init alpha & rotation alpha = Keyframe(0.0); rotation = Keyframe(0.0); // Init time & volume time = Keyframe(0.0); volume = Keyframe(1.0); // Init audio waveform color wave_color = (Color){Keyframe(0), Keyframe(28672), Keyframe(65280)}; // Init crop settings crop_gravity = GRAVITY_CENTER; crop_width = Keyframe(-1.0); crop_height = Keyframe(-1.0); crop_x = Keyframe(0.0); crop_y = Keyframe(0.0); // Init shear and perspective curves shear_x = Keyframe(0.0); shear_y = Keyframe(0.0); perspective_c1_x = Keyframe(-1.0); perspective_c1_y = Keyframe(-1.0); perspective_c2_x = Keyframe(-1.0); perspective_c2_y = Keyframe(-1.0); perspective_c3_x = Keyframe(-1.0); perspective_c3_y = Keyframe(-1.0); perspective_c4_x = Keyframe(-1.0); perspective_c4_y = Keyframe(-1.0); // Default pointers reader = NULL; resampler = NULL; audio_cache = NULL; } // Default Constructor for a clip Clip::Clip() { // Init all default settings init_settings(); } // Constructor with reader Clip::Clip(ReaderBase* reader) : reader(reader) { // Init all default settings init_settings(); // Open and Close the reader (to set the duration of the clip) Open(); Close(); // Update duration End(reader->info.duration); } // Constructor with filepath Clip::Clip(string path) { // Init all default settings init_settings(); // Get file extension (and convert to lower case) string ext = get_file_extension(path); transform(ext.begin(), ext.end(), ext.begin(), ::tolower); // Determine if common video formats if (ext=="avi" || ext=="mov" || ext=="mkv" || ext=="mpg" || ext=="mpeg" || ext=="mp3" || ext=="mp4" || ext=="mts" || ext=="ogg" || ext=="wav" || ext=="wmv" || ext=="webm" || ext=="vob") { try { // Open common video format reader = new FFmpegReader(path); } catch(...) { } } // If no video found, try each reader if (!reader) { try { // Try an image reader reader = new ImageReader(path); } catch(...) { try { // Try a video reader reader = new FFmpegReader(path); } catch(...) { } } } // Update duration if (reader) End(reader->info.duration); } /// Set the current reader void Clip::Reader(ReaderBase* new_reader) { // set reader pointer reader = new_reader; } /// Get the current reader ReaderBase* Clip::Reader() throw(ReaderClosed) { if (reader) return reader; else // Throw error if reader not initialized throw ReaderClosed("No Reader has been initialized for this Clip. Call Reader(*reader) before calling this method.", ""); } // Open the internal reader void Clip::Open() throw(InvalidFile, ReaderClosed) { if (reader) { // Open the reader reader->Open(); // Set some clip properties from the file reader if (end == 0.0) End(reader->info.duration); } else // Throw error if reader not initialized throw ReaderClosed("No Reader has been initialized for this Clip. Call Reader(*reader) before calling this method.", ""); } // Close the internal reader void Clip::Close() throw(ReaderClosed) { if (reader) { // Close the reader reader->Close(); } else // Throw error if reader not initialized throw ReaderClosed("No Reader has been initialized for this Clip. Call Reader(*reader) before calling this method.", ""); } // Get end position of clip (trim end of video), which can be affected by the time curve. float Clip::End() throw(ReaderClosed) { // if a time curve is present, use it's length if (time.Points.size() > 1) { // Determine the FPS fo this clip float fps = 24.0; if (reader) // file reader fps = reader->info.fps.ToFloat(); else // Throw error if reader not initialized throw ReaderClosed("No Reader has been initialized for this Clip. Call Reader(*reader) before calling this method.", ""); return float(time.GetLength()) / fps; } else // just use the duration (as detected by the reader) return end; } // Get an openshot::Frame object for a specific frame number of this reader. tr1::shared_ptr Clip::GetFrame(int requested_frame) throw(ReaderClosed) { if (reader) { // Adjust out of bounds frame number requested_frame = adjust_frame_number_minimum(requested_frame); // Is a time map detected int new_frame_number = requested_frame; if (time.Values.size() > 1) new_frame_number = time.GetInt(requested_frame); // Now that we have re-mapped what frame number is needed, go and get the frame pointer tr1::shared_ptr frame = reader->GetFrame(new_frame_number); // Get time mapped frame number (used to increase speed, change direction, etc...) tr1::shared_ptr new_frame = get_time_mapped_frame(frame, requested_frame); // Return processed 'frame' return new_frame; } else // Throw error if reader not initialized throw ReaderClosed("No Reader has been initialized for this Clip. Call Reader(*reader) before calling this method.", ""); } // Get file extension string Clip::get_file_extension(string path) { // return last part of path return path.substr(path.find_last_of(".") + 1); } // Reverse an audio buffer void Clip::reverse_buffer(juce::AudioSampleBuffer* buffer) { int number_of_samples = buffer->getNumSamples(); int channels = buffer->getNumChannels(); // Reverse array (create new buffer to hold the reversed version) AudioSampleBuffer *reversed = new juce::AudioSampleBuffer(channels, number_of_samples); reversed->clear(); for (int channel = 0; channel < channels; channel++) { int n=0; for (int s = number_of_samples - 1; s >= 0; s--, n++) reversed->getWritePointer(channel)[n] = buffer->getWritePointer(channel)[s]; } // Copy the samples back to the original array buffer->clear(); // Loop through channels, and get audio samples for (int channel = 0; channel < channels; channel++) // Get the audio samples for this channel buffer->addFrom(channel, 0, reversed->getReadPointer(channel), number_of_samples, 1.0f); delete reversed; reversed = NULL; } // Adjust the audio and image of a time mapped frame tr1::shared_ptr Clip::get_time_mapped_frame(tr1::shared_ptr frame, int frame_number) throw(ReaderClosed) { // Check for valid reader if (!reader) // Throw error if reader not initialized throw ReaderClosed("No Reader has been initialized for this Clip. Call Reader(*reader) before calling this method.", ""); tr1::shared_ptr new_frame; // Check for a valid time map curve if (time.Values.size() > 1) { // create buffer and resampler juce::AudioSampleBuffer *samples = NULL; if (!resampler) resampler = new AudioResampler(); // Get new frame number int new_frame_number = time.GetInt(frame_number); // Create a new frame int samples_in_frame = Frame::GetSamplesPerFrame(new_frame_number, reader->info.fps, reader->info.sample_rate); new_frame = tr1::shared_ptr(new Frame(new_frame_number, 1, 1, "#000000", samples_in_frame, frame->GetAudioChannelsCount())); // Copy the image from the new frame new_frame->AddImage(reader->GetFrame(new_frame_number)->GetImage()); // Get delta (difference in previous Y value) int delta = int(round(time.GetDelta(frame_number))); // Init audio vars int sample_rate = reader->info.sample_rate; int channels = reader->info.channels; int number_of_samples = reader->GetFrame(new_frame_number)->GetAudioSamplesCount(); // Determine if we are speeding up or slowing down if (time.GetRepeatFraction(frame_number).den > 1) { // Resample data, and return new buffer pointer AudioSampleBuffer *buffer = NULL; int resampled_buffer_size = 0; if (time.GetRepeatFraction(frame_number).num == 1) { // SLOW DOWN audio (split audio) samples = new juce::AudioSampleBuffer(channels, number_of_samples); samples->clear(); // Loop through channels, and get audio samples for (int channel = 0; channel < channels; channel++) // Get the audio samples for this channel samples->addFrom(channel, 0, reader->GetFrame(new_frame_number)->GetAudioSamples(channel), number_of_samples, 1.0f); // Reverse the samples (if needed) if (!time.IsIncreasing(frame_number)) reverse_buffer(samples); // Resample audio to be X times slower (where X is the denominator of the repeat fraction) resampler->SetBuffer(samples, 1.0 / time.GetRepeatFraction(frame_number).den); // Resample the data (since it's the 1st slice) buffer = resampler->GetResampledBuffer(); // Save the resampled data in the cache audio_cache = new juce::AudioSampleBuffer(channels, buffer->getNumSamples()); audio_cache->clear(); for (int channel = 0; channel < channels; channel++) // Get the audio samples for this channel audio_cache->addFrom(channel, 0, buffer->getReadPointer(channel), buffer->getNumSamples(), 1.0f); } // Get the length of the resampled buffer resampled_buffer_size = audio_cache->getNumSamples(); // Just take the samples we need for the requested frame int start = (number_of_samples * (time.GetRepeatFraction(frame_number).num - 1)); if (start > 0) start -= 1; for (int channel = 0; channel < channels; channel++) // Add new (slower) samples, to the frame object new_frame->AddAudio(true, channel, 0, audio_cache->getReadPointer(channel, start), number_of_samples, 1.0f); // Clean up if the final section if (time.GetRepeatFraction(frame_number).num == time.GetRepeatFraction(frame_number).den) { // Clear, since we don't want it maintain state yet delete audio_cache; audio_cache = NULL; } // Clean up buffer = NULL; // Determine next unique frame (after these repeating frames) //int next_unique_frame = time.GetInt(frame_number + (time.GetRepeatFraction(frame_number).den - time.GetRepeatFraction(frame_number).num) + 1); //if (next_unique_frame != new_frame_number) // // Overlay the next frame on top of this frame (to create a smoother slow motion effect) // new_frame->AddImage(reader->GetFrame(next_unique_frame)->GetImage(), float(time.GetRepeatFraction(frame_number).num) / float(time.GetRepeatFraction(frame_number).den)); } else if (abs(delta) > 1 && abs(delta) < 100) { // SPEED UP (multiple frames of audio), as long as it's not more than X frames samples = new juce::AudioSampleBuffer(channels, number_of_samples * abs(delta)); samples->clear(); int start = 0; if (delta > 0) { // Loop through each frame in this delta for (int delta_frame = new_frame_number - (delta - 1); delta_frame <= new_frame_number; delta_frame++) { // buffer to hold detal samples int number_of_delta_samples = reader->GetFrame(delta_frame)->GetAudioSamplesCount(); AudioSampleBuffer* delta_samples = new juce::AudioSampleBuffer(channels, number_of_delta_samples); delta_samples->clear(); for (int channel = 0; channel < channels; channel++) delta_samples->addFrom(channel, 0, reader->GetFrame(delta_frame)->GetAudioSamples(channel), number_of_delta_samples, 1.0f); // Reverse the samples (if needed) if (!time.IsIncreasing(frame_number)) reverse_buffer(delta_samples); // Copy the samples to for (int channel = 0; channel < channels; channel++) // Get the audio samples for this channel samples->addFrom(channel, start, delta_samples->getReadPointer(channel), number_of_delta_samples, 1.0f); // Clean up delete delta_samples; delta_samples = NULL; // Increment start position start += number_of_delta_samples; } } else { // Loop through each frame in this delta for (int delta_frame = new_frame_number - (delta + 1); delta_frame >= new_frame_number; delta_frame--) { // buffer to hold delta samples int number_of_delta_samples = reader->GetFrame(delta_frame)->GetAudioSamplesCount(); AudioSampleBuffer* delta_samples = new juce::AudioSampleBuffer(channels, number_of_delta_samples); delta_samples->clear(); for (int channel = 0; channel < channels; channel++) delta_samples->addFrom(channel, 0, reader->GetFrame(delta_frame)->GetAudioSamples(channel), number_of_delta_samples, 1.0f); // Reverse the samples (if needed) if (!time.IsIncreasing(frame_number)) reverse_buffer(delta_samples); // Copy the samples to for (int channel = 0; channel < channels; channel++) // Get the audio samples for this channel samples->addFrom(channel, start, delta_samples->getReadPointer(channel), number_of_delta_samples, 1.0f); // Clean up delete delta_samples; delta_samples = NULL; // Increment start position start += number_of_delta_samples; } } // Resample audio to be X times faster (where X is the delta of the repeat fraction) resampler->SetBuffer(samples, float(start) / float(number_of_samples)); // Resample data, and return new buffer pointer AudioSampleBuffer *buffer = resampler->GetResampledBuffer(); int resampled_buffer_size = buffer->getNumSamples(); // Add the newly resized audio samples to the current frame for (int channel = 0; channel < channels; channel++) // Add new (slower) samples, to the frame object new_frame->AddAudio(true, channel, 0, buffer->getReadPointer(channel), number_of_samples, 1.0f); // Clean up buffer = NULL; } else { // Use the samples on this frame (but maybe reverse them if needed) samples = new juce::AudioSampleBuffer(channels, number_of_samples); samples->clear(); // Loop through channels, and get audio samples for (int channel = 0; channel < channels; channel++) // Get the audio samples for this channel samples->addFrom(channel, 0, frame->GetAudioSamples(channel), number_of_samples, 1.0f); // reverse the samples if (!time.IsIncreasing(frame_number)) reverse_buffer(samples); // Add reversed samples to the frame object for (int channel = 0; channel < channels; channel++) new_frame->AddAudio(true, channel, 0, samples->getReadPointer(channel), number_of_samples, 1.0f); } // clean up //delete resampler; //resampler = NULL; delete samples; samples = NULL; } else // Use original frame return frame; // Return new time mapped frame return new_frame; } // Adjust frame number minimum value int Clip::adjust_frame_number_minimum(int frame_number) { // Never return a frame number 0 or below if (frame_number < 1) return 1; else return frame_number; } // Generate JSON string of this object string Clip::Json() { // Return formatted string return JsonValue().toStyledString(); } // Get all properties for a specific frame string Clip::PropertiesJSON(int requested_frame) { // Requested Point Point requested_point(requested_frame, requested_frame); // Generate JSON properties list Json::Value root; root["id"] = add_property_json("ID", 0.0, "string", Id(), false, 0, -1, -1, CONSTANT, -1, true); root["position"] = add_property_json("Position", Position(), "int", "", false, 0, 0, 1000 * 60 * 30, CONSTANT, -1, false); root["layer"] = add_property_json("Layer", Layer(), "int", "", false, 0, 0, 1000, CONSTANT, -1, false); root["start"] = add_property_json("Start", Start(), "float", "", false, 0, 0, 1000 * 60 * 30, CONSTANT, -1, false); root["end"] = add_property_json("End", End(), "float", "", false, 0, 0, 1000 * 60 * 30, CONSTANT, -1, false); root["duration"] = add_property_json("Duration", Duration(), "float", "", false, 0, 0, 1000 * 60 * 30, CONSTANT, -1, false); root["gravity"] = add_property_json("Gravity", gravity, "int", "", false, 0, -1, -1, CONSTANT, -1, false); root["scale"] = add_property_json("Scale", scale, "int", "", false, 0, -1, -1, CONSTANT, -1, false); root["anchor"] = add_property_json("Anchor", anchor, "int", "", false, 0, -1, -1, CONSTANT, -1, false); root["waveform"] = add_property_json("Waveform", waveform, "int", "", false, 0, -1, -1, CONSTANT, -1, false); // Keyframes root["location_x"] = add_property_json("Location X", location_x.GetValue(requested_frame), "float", "", location_x.Contains(requested_point), location_x.GetCount(), -10000, 10000, location_x.GetClosestPoint(requested_point).interpolation, location_x.GetClosestPoint(requested_point).co.X, false); root["location_y"] = add_property_json("Location Y", location_y.GetValue(requested_frame), "float", "", location_y.Contains(requested_point), location_y.GetCount(), -10000, 10000, location_y.GetClosestPoint(requested_point).interpolation, location_y.GetClosestPoint(requested_point).co.X, false); root["scale_x"] = add_property_json("Scale X", scale_x.GetValue(requested_frame), "float", "", scale_x.Contains(requested_point), scale_x.GetCount(), 0.0, 100.0, scale_x.GetClosestPoint(requested_point).interpolation, scale_x.GetClosestPoint(requested_point).co.X, false); root["scale_y"] = add_property_json("Scale Y", scale_y.GetValue(requested_frame), "float", "", scale_y.Contains(requested_point), scale_y.GetCount(), 0.0, 100.0, scale_y.GetClosestPoint(requested_point).interpolation, scale_y.GetClosestPoint(requested_point).co.X, false); root["alpha"] = add_property_json("Alpha", alpha.GetValue(requested_frame), "float", "", alpha.Contains(requested_point), alpha.GetCount(), 0.0, 1.0, alpha.GetClosestPoint(requested_point).interpolation, alpha.GetClosestPoint(requested_point).co.X, false); root["rotation"] = add_property_json("Rotation", rotation.GetValue(requested_frame), "float", "", rotation.Contains(requested_point), rotation.GetCount(), -10000, 10000, rotation.GetClosestPoint(requested_point).interpolation, rotation.GetClosestPoint(requested_point).co.X, false); root["volume"] = add_property_json("Volume", volume.GetValue(requested_frame), "float", "", volume.Contains(requested_point), volume.GetCount(), 0.0, 1.0, volume.GetClosestPoint(requested_point).interpolation, volume.GetClosestPoint(requested_point).co.X, false); root["time"] = add_property_json("Time", time.GetValue(requested_frame), "float", "", time.Contains(requested_point), time.GetCount(), 0.0, 1000 * 60 * 30, time.GetClosestPoint(requested_point).interpolation, time.GetClosestPoint(requested_point).co.X, false); // Keep track of settings string stringstream properties; properties << 0.0f << Position() << Layer() << Start() << End() << Duration() << gravity << scale << anchor << waveform << location_x.GetValue(requested_frame) << location_y.GetValue(requested_frame) << scale_x.GetValue(requested_frame) << scale_y.GetValue(requested_frame) << alpha.GetValue(requested_frame) << rotation.GetValue(requested_frame) << volume.GetValue(requested_frame) << time.GetValue(requested_frame) << alpha.GetCount() << alpha.GetClosestPoint(requested_point).interpolation << alpha.GetClosestPoint(requested_point).co.X; // Have they changed since the previous call? bool changed = false; if (properties.str() != previous_properties) { changed = true; previous_properties = properties.str(); } // Mark JSON as changed root["changed"] = add_property_json("changed", changed, "bool", "", false, 0, 0, 1, CONSTANT, -1, true); root["hash"] = add_property_json("hash", 0.0, "string", properties.str(), false, 0, 0, 1, CONSTANT, -1, true); // Return formatted string return root.toStyledString(); } // Generate JSON for a property Json::Value Clip::add_property_json(string name, float value, string type, string memo, bool contains_point, int number_of_points, float min_value, float max_value, InterpolationType intepolation, int closest_point_x, bool readonly) { // Create JSON Object Json::Value prop = Json::Value(Json::objectValue); prop["name"] = name; prop["value"] = value; prop["memo"] = memo; prop["type"] = value; prop["min"] = min_value; prop["max"] = max_value; prop["keyframe"] = contains_point; prop["points"] = number_of_points; prop["readonly"] = max_value; prop["interpolation"] = intepolation; prop["closest_point_x"] = closest_point_x; // return JsonValue return prop; } // Generate Json::JsonValue for this object Json::Value Clip::JsonValue() { // Create root json object Json::Value root = ClipBase::JsonValue(); // get parent properties root["gravity"] = gravity; root["scale"] = scale; root["anchor"] = anchor; root["waveform"] = waveform; root["scale_x"] = scale_x.JsonValue(); root["scale_y"] = scale_y.JsonValue(); root["location_x"] = location_x.JsonValue(); root["location_y"] = location_y.JsonValue(); root["alpha"] = alpha.JsonValue(); root["rotation"] = rotation.JsonValue(); root["time"] = time.JsonValue(); root["volume"] = volume.JsonValue(); root["wave_color"] = wave_color.JsonValue(); root["crop_width"] = crop_width.JsonValue(); root["crop_height"] = crop_height.JsonValue(); root["crop_x"] = crop_x.JsonValue(); root["crop_y"] = crop_y.JsonValue(); root["shear_x"] = shear_x.JsonValue(); root["shear_y"] = shear_y.JsonValue(); root["perspective_c1_x"] = perspective_c1_x.JsonValue(); root["perspective_c1_y"] = perspective_c1_y.JsonValue(); root["perspective_c2_x"] = perspective_c2_x.JsonValue(); root["perspective_c2_y"] = perspective_c2_y.JsonValue(); root["perspective_c3_x"] = perspective_c3_x.JsonValue(); root["perspective_c3_y"] = perspective_c3_y.JsonValue(); root["perspective_c4_x"] = perspective_c4_x.JsonValue(); root["perspective_c4_y"] = perspective_c4_y.JsonValue(); if (reader) root["reader"] = reader->JsonValue(); // return JsonValue return root; } // Load JSON string into this object void Clip::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 Clip::SetJsonValue(Json::Value root) { // Set parent data ClipBase::SetJsonValue(root); // Set data from Json (if key is found) if (!root["gravity"].isNull()) gravity = (GravityType) root["gravity"].asInt(); if (!root["scale"].isNull()) scale = (ScaleType) root["scale"].asInt(); if (!root["anchor"].isNull()) anchor = (AnchorType) root["anchor"].asInt(); if (!root["waveform"].isNull()) waveform = root["waveform"].asBool(); if (!root["scale_x"].isNull()) scale_x.SetJsonValue(root["scale_x"]); if (!root["scale_y"].isNull()) scale_y.SetJsonValue(root["scale_y"]); if (!root["location_x"].isNull()) location_x.SetJsonValue(root["location_x"]); if (!root["location_y"].isNull()) location_y.SetJsonValue(root["location_y"]); if (!root["alpha"].isNull()) alpha.SetJsonValue(root["alpha"]); if (!root["rotation"].isNull()) rotation.SetJsonValue(root["rotation"]); if (!root["time"].isNull()) time.SetJsonValue(root["time"]); if (!root["volume"].isNull()) volume.SetJsonValue(root["volume"]); if (!root["wave_color"].isNull()) wave_color.SetJsonValue(root["wave_color"]); if (!root["crop_width"].isNull()) crop_width.SetJsonValue(root["crop_width"]); if (!root["crop_height"].isNull()) crop_height.SetJsonValue(root["crop_height"]); if (!root["crop_x"].isNull()) crop_x.SetJsonValue(root["crop_x"]); if (!root["crop_y"].isNull()) crop_y.SetJsonValue(root["crop_y"]); if (!root["shear_x"].isNull()) shear_x.SetJsonValue(root["shear_x"]); if (!root["shear_y"].isNull()) shear_y.SetJsonValue(root["shear_y"]); if (!root["perspective_c1_x"].isNull()) perspective_c1_x.SetJsonValue(root["perspective_c1_x"]); if (!root["perspective_c1_y"].isNull()) perspective_c1_y.SetJsonValue(root["perspective_c1_y"]); if (!root["perspective_c2_x"].isNull()) perspective_c2_x.SetJsonValue(root["perspective_c2_x"]); if (!root["perspective_c2_y"].isNull()) perspective_c2_y.SetJsonValue(root["perspective_c2_y"]); if (!root["perspective_c3_x"].isNull()) perspective_c3_x.SetJsonValue(root["perspective_c3_x"]); if (!root["perspective_c3_y"].isNull()) perspective_c3_y.SetJsonValue(root["perspective_c3_y"]); if (!root["perspective_c4_x"].isNull()) perspective_c4_x.SetJsonValue(root["perspective_c4_x"]); if (!root["perspective_c4_y"].isNull()) perspective_c4_y.SetJsonValue(root["perspective_c4_y"]); if (!root["reader"].isNull()) // does Json contain a reader? { if (!root["reader"]["type"].isNull()) // does the reader Json contain a 'type'? { // Close previous reader (if any) bool already_open = false; if (reader) { // Track if reader was open already_open = reader->IsOpen(); // Close and delete existing reader (if any) reader->Close(); delete reader; reader = NULL; } // Create new reader (and load properties) string type = root["reader"]["type"].asString(); if (type == "FFmpegReader") { // Create new reader reader = new FFmpegReader(root["reader"]["path"].asString()); reader->SetJsonValue(root["reader"]); } else if (type == "ImageReader") { // Create new reader reader = new ImageReader(root["reader"]["path"].asString()); reader->SetJsonValue(root["reader"]); } else if (type == "TextReader") { // Create new reader reader = new TextReader(); reader->SetJsonValue(root["reader"]); } else if (type == "ChunkReader") { // Create new reader reader = new ChunkReader(root["reader"]["path"].asString(), (ChunkVersion) root["reader"]["chunk_version"].asInt()); reader->SetJsonValue(root["reader"]); } else if (type == "DummyReader") { // Create new reader reader = new DummyReader(); reader->SetJsonValue(root["reader"]); } // Re-Open reader (if needed) if (already_open) reader->Open(); } } }