Aegisub/src/async_video_provider.h

160 lines
6.4 KiB
C++

// Copyright (c) 2013, Thomas Goyne <plorkyeran@aegisub.org>
//
// Permission to use, copy, modify, and distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
//
// Aegisub Project http://www.aegisub.org/
#include "include/aegisub/video_provider.h"
#include <libaegisub/exception.h>
#include <libaegisub/fs_fwd.h>
#include <atomic>
#include <memory>
#include <set>
#include <wx/event.h>
class AssDialogue;
class AssFile;
class SubtitlesProvider;
class VideoProvider;
class VideoProviderError;
struct AssDialogueBase;
struct VideoFrame;
namespace agi {
class BackgroundRunner;
namespace dispatch { class Queue; }
}
/// An asynchronous video decoding and subtitle rendering wrapper
class AsyncVideoProvider {
/// Asynchronous work queue
std::unique_ptr<agi::dispatch::Queue> worker;
/// Subtitles provider
std::unique_ptr<SubtitlesProvider> subs_provider;
/// Video provider
std::unique_ptr<VideoProvider> source_provider;
/// Event handler to send FrameReady events to
wxEvtHandler *parent;
int frame_number = -1; ///< Last frame number requested
double time = -1.; ///< Time of the frame to pass to the subtitle renderer
/// Copy of the subtitles file to avoid having to touch the project context
std::unique_ptr<AssFile> subs;
/// If >= 0, the subtitles provider current has just the lines visible on
/// that frame loaded. If -1, the entire file is loaded. If -2, the
/// currently loaded file is out of date.
int single_frame = -1;
/// Last rendered frame number
int last_rendered = -1;
/// Last rendered subtitles on that frame
std::vector<AssDialogueBase> last_lines;
/// Check if we actually need to honor a frame request or if no visible
/// lines have actually changed
bool NeedUpdate(std::vector<AssDialogueBase const*> const& visible_lines);
std::shared_ptr<VideoFrame> ProcFrame(int frame, double time, bool raw = false);
/// Produce a frame if req_version is still the current version
void ProcAsync(uint_fast32_t req_version, bool check_updated);
/// Monotonic counter used to drop frames when changes arrive faster than
/// they can be rendered
std::atomic<uint_fast32_t> version{ 0 };
std::vector<std::shared_ptr<VideoFrame>> buffers;
public:
/// @brief Load the passed subtitle file
/// @param subs File to load
///
/// This function blocks until is it is safe for the calling thread to
/// modify subs
void LoadSubtitles(const AssFile *subs) throw();
/// @brief Update a previously loaded subtitle file
/// @param subs Subtitle file which was last passed to LoadSubtitles
/// @param changes Set of lines which have changed
///
/// This function only supports changes to existing lines, and not
/// insertions or deletions.
void UpdateSubtitles(const AssFile *subs, const AssDialogue *changes) throw();
/// @brief Queue a request for a frame
/// @brief frame Frame number
/// @brief time Exact start time of the frame in seconds
///
/// This merely queues up a request and deletes any pending requests; there
/// is no guarantee that the requested frame will ever actually be produced
void RequestFrame(int frame, double time) throw();
/// @brief Synchronously get a frame
/// @brief frame Frame number
/// @brief time Exact start time of the frame in seconds
/// @brief raw Get raw frame without subtitles
std::shared_ptr<VideoFrame> GetFrame(int frame, double time, bool raw = false);
/// Ask the video provider to change YCbCr matricies
void SetColorSpace(std::string const& matrix);
int GetFrameCount() const { return source_provider->GetFrameCount(); }
int GetWidth() const { return source_provider->GetWidth(); }
int GetHeight() const { return source_provider->GetHeight(); }
double GetDAR() const { return source_provider->GetDAR(); }
agi::vfr::Framerate GetFPS() const { return source_provider->GetFPS(); }
std::vector<int> GetKeyFrames() const { return source_provider->GetKeyFrames(); }
std::string GetColorSpace() const { return source_provider->GetColorSpace(); }
std::string GetRealColorSpace() const { return source_provider->GetRealColorSpace(); }
std::string GetWarning() const { return source_provider->GetWarning(); }
std::string GetDecoderName() const { return source_provider->GetDecoderName(); }
bool ShouldSetVideoProperties() const { return source_provider->ShouldSetVideoProperties(); }
bool HasAudio() const { return source_provider->HasAudio(); }
/// @brief Constructor
/// @param videoFileName File to open
/// @param parent Event handler to send FrameReady events to
AsyncVideoProvider(agi::fs::path const& filename, std::string const& colormatrix, wxEvtHandler *parent, agi::BackgroundRunner *br);
~AsyncVideoProvider();
};
/// Event which signals that a requested frame is ready
struct FrameReadyEvent final : public wxEvent {
/// Frame which is ready
std::shared_ptr<VideoFrame> frame;
/// Time which was used for subtitle rendering
double time;
wxEvent *Clone() const override { return new FrameReadyEvent(*this); };
FrameReadyEvent(std::shared_ptr<VideoFrame> frame, double time)
: frame(std::move(frame)), time(time) { }
};
// These exceptions are wxEvents so that they can be passed directly back to
// the parent thread as events
struct VideoProviderErrorEvent final : public wxEvent, public agi::Exception {
wxEvent *Clone() const override { return new VideoProviderErrorEvent(*this); };
VideoProviderErrorEvent(VideoProviderError const& err);
};
struct SubtitlesProviderErrorEvent final : public wxEvent, public agi::Exception {
wxEvent *Clone() const override { return new SubtitlesProviderErrorEvent(*this); };
SubtitlesProviderErrorEvent(std::string const& msg);
};
wxDECLARE_EVENT(EVT_FRAME_READY, FrameReadyEvent);
wxDECLARE_EVENT(EVT_VIDEO_ERROR, VideoProviderErrorEvent);
wxDECLARE_EVENT(EVT_SUBTITLES_ERROR, SubtitlesProviderErrorEvent);