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Commit 7497299f authored by Hugo Beauzée-Luyssen's avatar Hugo Beauzée-Luyssen
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MediaPlayer: Handle event callbacks

parent 9c64fb89
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src/EventManager.hpp
View file @ 7497299f
......@@ -54,20 +54,6 @@ protected:
template <typename T>
using DecayPtr = typename std::add_pointer<typename std::decay<T>::type>::type;
template <typename, typename, typename = void>
struct signature_match : std::false_type {};
// Kudos to 3xxO
template <typename Func, typename Ret, typename... Args>
struct signature_match<Func, Ret(Args...),
typename std::enable_if<
std::is_convertible<
decltype(std::declval<Func>()(std::declval<Args>()...)),
Ret
>::value
>::type
> : std::true_type {};
private:
// Polymorphic base to hold a templated implementation
struct EventHandlerBase
......
src/MediaPlayer.hpp
View file @ 7497299f
......@@ -24,8 +24,10 @@
#ifndef LIBVLC_CXX_MEDIAPLAYER_H
#define LIBVLC_CXX_MEDIAPLAYER_H
#include <array>
#include <string>
#include <vector>
#include <memory>
#include "common.hpp"
......@@ -38,8 +40,26 @@ class Instance;
class Media;
class MediaPlayerEventManager;
class MediaPlayer : public Internal<libvlc_media_player_t>
class MediaPlayer : public Internal<libvlc_media_player_t>, public EventOwner<13>
{
private:
enum class EventIdx : unsigned int
{
AudioPlay,
AudioPause,
AudioResume,
AudioFlush,
AudioDrain,
AudioVolume,
AudioSetup,
AudioCleanup,
VideoLock,
VideoUnlock,
VideoDisplay,
VideoFormat,
VideoCleanup,
};
public:
/**
* Check if 2 MediaPlayer objects contain the same libvlc_media_player_t.
......@@ -648,24 +668,41 @@ public:
* MediaPlayer::setFormat() or MediaPlayer::setFormatCallbacks() to configure the
* decoded audio format.
*
* \param play callback to play audio samples (must not be NULL)
*
* \param pause callback to pause playback (or NULL to ignore)
* \param play callback to play audio samples (must not be nullptr)
* Required prototype is: void(const void *samples, unsigned count, int64_t pts)
*
* \param resume callback to resume playback (or NULL to ignore)
* \param pause callback to pause playback (or nullptr to ignore)
* Required prototype is void(int64_t pts);
*
* \param flush callback to flush audio buffers (or NULL to ignore)
* \param resume callback to resume playback (or nullptr to ignore)
* Required prototype is void(int64_t pts);
*
* \param drain callback to drain audio buffers (or NULL to ignore)
* \param flush callback to flush audio buffers (or nullptr to ignore)
* Required prototype is void(int64_t pts);
*
* \param opaque private pointer for the audio callbacks (as first
* parameter)
* \param drain callback to drain audio buffers (or nullptr to ignore)
* * Required prototype is void();
*
* \version LibVLC 2.0.0 or later
*/
void setAudioCallbacks(libvlc_audio_play_cb play, libvlc_audio_pause_cb pause, libvlc_audio_resume_cb resume, libvlc_audio_flush_cb flush, libvlc_audio_drain_cb drain, void * opaque)
template <typename PlayCb, typename PauseCb, typename ResumeCb, typename FlushCb, typename DrainCb>
void setAudioCallbacks(PlayCb&& play, PauseCb&& pause, ResumeCb&& resume, FlushCb&& flush, DrainCb&& drain)
{
libvlc_audio_set_callbacks(*this, play, pause, resume, flush, drain, opaque);
static_assert(signature_match<PlayCb, void(const void*, unsigned int, int64_t)>::value, "Mismatched play callback prototype");
static_assert(signature_match_or_nullptr<PauseCb, void(int64_t)>::value, "Mismatched pause callback prototype");
static_assert(signature_match_or_nullptr<ResumeCb, void(int64_t)>::value, "Mismatched resume callback prototype");
static_assert(signature_match_or_nullptr<FlushCb, void(int64_t pts)>::value, "Mismatched flush callback prototype");
static_assert(signature_match_or_nullptr<DrainCb, void()>::value, "Mismatched drain callback prototype");
libvlc_audio_set_callbacks( *this,
CallbackWrapper<(int)EventIdx::AudioPlay, PlayCb, libvlc_audio_play_cb>::wrap( this, std::forward<PlayCb>( play ) ),
CallbackWrapper<(int)EventIdx::AudioPause, PauseCb, libvlc_audio_pause_cb>::wrap( this, std::forward<PauseCb>( pause ) ),
CallbackWrapper<(int)EventIdx::AudioResume, ResumeCb,libvlc_audio_resume_cb>::wrap( this, std::forward<ResumeCb>( resume ) ),
CallbackWrapper<(int)EventIdx::AudioFlush, FlushCb, libvlc_audio_flush_cb>::wrap( this, std::forward<FlushCb>( flush ) ),
CallbackWrapper<(int)EventIdx::AudioDrain, DrainCb, libvlc_audio_drain_cb>::wrap( this, std::forward<DrainCb>( drain ) ),
// We will receive the pointer as a void*, we need to offset the value *now*, otherwise we'd get
// a shifted value, resulting in an empty callback array.
static_cast<EventOwner<13>*>( this ) );
}
/**
......@@ -673,29 +710,42 @@ public:
* MediaPlayer::setFormat() or MediaPlayer::setFormatCallbacks() to configure the
* decoded audio format.
*
* \param set_volume callback to apply audio volume, or NULL to apply
* volume in software
* \param set_volume callback to apply audio volume, or nullptr to apply
* volume in software
* Expected prototype is void(float volume, bool mute)
*
* \version LibVLC 2.0.0 or later
*/
void setVolumeCallback(libvlc_audio_set_volume_cb set_volume)
template <typename VolumeCb>
void setVolumeCallback(VolumeCb&& func)
{
libvlc_audio_set_volume_callback(*this, set_volume);
static_assert(signature_match_or_nullptr<VolumeCb, void(float, bool)>::value, "Mismatched set volume callback");
libvlc_audio_set_volume_callback(*this,
CallbackWrapper<(int)EventIdx::AudioVolume, VolumeCb, libvlc_audio_set_volume_cb>::wrap( this, std::forward<VolumeCb>( func ) ) );
}
/**
* Set decoded audio format. This only works in combination with
* MediaPlayer::setCallbacks() .
*
* \param setup callback to select the audio format (cannot be NULL)
* \param setup callback to select the audio format (cannot be a nullptr)
* Expected prototype is int(char *format, unsigned *rate, unsigned *channels)
* Where the return value is 0 for success, anything else to skip audio playback
*
* \param cleanup callback to release any allocated resources (or NULL)
* \param cleanup callback to release any allocated resources (or nullptr)
* Expected prototype is void()
*
* \version LibVLC 2.0.0 or later
*/
void setAudioFormatCallbacks(libvlc_audio_setup_cb setup, libvlc_audio_cleanup_cb cleanup)
template <typename SetupCb, typename CleanupCb>
void setAudioFormatCallbacks(SetupCb&& setup, CleanupCb&& cleanup)
{
libvlc_audio_set_format_callbacks(*this, setup, cleanup);
static_assert(signature_match<SetupCb, int(char*, uint32_t*, uint32_t*)>::value, "Mismatched Setup callback");
static_assert(signature_match_or_nullptr<CleanupCb, void()>::value, "Mismatched cleanup callback");
libvlc_audio_set_format_callbacks(*this,
CallbackWrapper<(int)EventIdx::AudioSetup, SetupCb, libvlc_audio_setup_cb>::wrap( this, std::forward<SetupCb>( setup ) ),
CallbackWrapper<(int)EventIdx::AudioCleanup, CleanupCb, libvlc_audio_cleanup_cb>::wrap( this, std::forward<CleanupCb>( cleanup ) ) );
}
/**
......@@ -977,20 +1027,36 @@ public:
* area in memory. Use MediaPlayer::setFormat() or MediaPlayer::setFormatCallbacks()
* to configure the decoded format.
*
* \param lock callback to lock video memory (must not be NULL)
* \param lock callback to lock video memory (must not be nullptr)
* Expected prototype is void*(void** planes)
* planes is a pointer to an array of planes, that must be provided with some allocated buffers
* Return value is a picture identifier, to be passed to unlock & display callbacks
*
* \param unlock callback to unlock video memory (or NULL if not needed)
* \param unlock callback to unlock video memory (or nullptr if not needed)
* Expected prototype is void(void* pictureId, void*const* planes);
* pictureId is the value returned by the lock callback.
* planes is the planes provided by the lock callback
*
* \param display callback to display video (or NULL if not needed)
*
* \param opaque private pointer for the three callbacks (as first
* parameter)
* \param display callback to display video (or nullptr if not needed)
* Expected prototype is void(void* pictureId);
* pictureId is the value returned by the lock callback.
*
* \version LibVLC 1.1.1 or later
*/
void setVideoCallbacks(libvlc_video_lock_cb lock, libvlc_video_unlock_cb unlock, libvlc_video_display_cb display, void * opaque)
template <typename LockCb, typename UnlockCb, typename DisplayCb>
void setVideoCallbacks(LockCb&& lock, UnlockCb&& unlock, DisplayCb&& display)
{
libvlc_video_set_callbacks(*this, lock, unlock, display, opaque);
static_assert(signature_match<LockCb, void*(void**)>::value, "Mismatched lock callback signature");
static_assert(signature_match_or_nullptr<UnlockCb, void(void*, void *const *)>::value, "Mismatched unlock callback signature");
static_assert(signature_match_or_nullptr<DisplayCb, void(void*)>::value, "Mismatched lock callback signature");
libvlc_video_set_callbacks(*this,
CallbackWrapper<(int)EventIdx::VideoLock, LockCb, libvlc_video_lock_cb>::wrap( this, std::forward<LockCb>( lock ) ),
CallbackWrapper<(int)EventIdx::VideoUnlock, UnlockCb, libvlc_video_unlock_cb>::wrap( this, std::forward<UnlockCb>( unlock ) ),
CallbackWrapper<(int)EventIdx::VideoDisplay, DisplayCb, libvlc_video_display_cb>::wrap( this, std::forward<DisplayCb>( display ) ),
// We will receive the pointer as a void*, we need to offset the value *now*, otherwise we'd get
// a shifted value, resulting in an empty callback array.
static_cast<EventOwner<13>*>( this ) );
}
/**
......@@ -1018,15 +1084,29 @@ public:
* Set decoded video chroma and dimensions. This only works in
* combination with MediaPlayer::setCallbacks() .
*
* \param setup callback to select the video format (cannot be NULL)
* \param setup callback to lock video memory (must not be nullptr)
* Expected prototype is uint32_t(char *chroma, // Must be filled with the required fourcc
* unsigned *width, // Must be filled with the required width
* unsigned *height, // Must be filled with the required height
* unsigned *pitches, // Must be filled with the required pitch for each plane
* unsigned *lines); // Must be filled with the required number of lines for each plane
* The return value reprensent the amount of pictures to create in a pool. 0 to indicate an error
*
* \param cleanup callback to release any allocated resources (or NULL)
* \param cleanup callback to release any allocated resources (or nullptr)
* Expected prototype is void()
*
* \version LibVLC 2.0.0 or later
*/
void setVideoFormatCallbacks(libvlc_video_format_cb setup, libvlc_video_cleanup_cb cleanup)
template <typename FormatCb, typename CleanupCb>
void setVideoFormatCallbacks(FormatCb&& setup, CleanupCb&& cleanup)
{
libvlc_video_set_format_callbacks(*this, setup, cleanup);
static_assert(signature_match<FormatCb, uint32_t(char*, uint32_t*, uint32_t*, uint32_t*, uint32_t*)>::value,
"Unmatched prototype for format callback" );
static_assert(signature_match_or_nullptr<CleanupCb, void()>::value, "Unmatched prototype for cleanup callback");
libvlc_video_set_format_callbacks(*this,
CallbackWrapper<(int)EventIdx::VideoFormat, FormatCb, libvlc_video_format_cb>::wrap( static_cast<EventOwner<13>*>( this ), std::forward<FormatCb>( setup ) ),
CallbackWrapper<(int)EventIdx::VideoCleanup, CleanupCb, libvlc_video_cleanup_cb>::wrap( this, std::forward<CleanupCb>( cleanup ) ) );
}
/**
......
src/common.hpp
View file @ 7497299f
......@@ -3,8 +3,8 @@
*****************************************************************************
* Copyright © 2015 libvlcpp authors & VideoLAN
*
* Authors: Alexey Sokolov <alexey@alexeysokolov.co.cc>
* Hugo Beauzée-Luyssen <hugo@beauzee.fr>
* Authors: Hugo Beauzée-Luyssen <hugo@beauzee.fr>
* Jonathan Calmels <exxo@videolabs.io>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
......@@ -25,6 +25,7 @@
#define LIBVLC_CXX_COMMON_H
#include <vlc/vlc.h>
#include <cassert>
#include <memory>
namespace VLC
......@@ -50,6 +51,110 @@ namespace VLC
{
return std::unique_ptr<char, void(*)(void*)>( str, [](void* ptr) { libvlc_free(ptr); } );
}
// Kudos to 3xxO for the signature_match helper
template <typename, typename, typename = void>
struct signature_match : std::false_type {};
template <typename Func, typename Ret, typename... Args>
struct signature_match<Func, Ret(Args...),
typename std::enable_if<
std::is_convertible<
decltype(std::declval<Func>()(std::declval<Args>()...)),
Ret
>::value // true or false
>::type // void or SFINAE
> : std::true_type {};
template <typename Func, typename Ret, typename... Args>
struct signature_match_or_nullptr : std::integral_constant<bool,
signature_match<Func, Ret, Args...>::value ||
std::is_same<Func, std::nullptr_t>::value
>
{
};
struct CallbackHandlerBase
{
virtual ~CallbackHandlerBase() = default;
};
template <typename Func>
struct CallbackHandler : public CallbackHandlerBase
{
CallbackHandler(Func&& f) : func( std::forward<Func>( f ) ) {}
Func func;
};
template <int NbEvent>
struct EventOwner
{
std::array<std::shared_ptr<CallbackHandlerBase>, NbEvent> callbacks;
protected:
EventOwner() = default;
};
template <int Idx, typename Func, typename... Args>
struct CallbackWrapper;
// We assume that any callback will take a void* opaque as its first parameter.
// We intercept this parameter, and use it to fetch the list of user provided
// functions. Once we know what function to call, we forward the rest of the
// parameters.
// Using partial specialization also allows us to get the list of the expected
// callback parameters automatically, rather than having to specify them.
template <int Idx, typename Func, typename Ret, typename... Args>
struct CallbackWrapper<Idx, Func, Ret(*)(void*, Args...)>
{
using Wrapped = Ret(void*, Args...);
template <int NbEvents>
static Wrapped* wrap(EventOwner<NbEvents>* owner, Func&& func)
{
owner->callbacks[Idx] = std::shared_ptr<CallbackHandlerBase>( new CallbackHandler<Func>( std::forward<Func>( func ) ) );
return [](void* opaque, Args... args) -> Ret {
auto self = reinterpret_cast<EventOwner<NbEvents>*>(opaque);
assert(self->callbacks[Idx].get());
auto cbHandler = static_cast<CallbackHandler<Func>*>( self->callbacks[Idx].get() );
return cbHandler->func( std::forward<Args>(args)... );
};
}
};
// Special handling for events with a void** opaque first parameter.
// We fetch it and do our business with it, then forward the parameters
// to the user callback, without this opaque param.
template <int Idx, typename Func, typename Ret, typename... Args>
struct CallbackWrapper<Idx, Func, Ret(*)(void**, Args...)>
{
using Wrapped = Ret(void**, Args...);
template <int NbEvents>
static Wrapped* wrap(EventOwner<NbEvents>* owner, Func&& func)
{
owner->callbacks[Idx] = std::shared_ptr<CallbackHandlerBase>( new CallbackHandler<Func>( std::forward<Func>( func ) ) );
return [](void** opaque, Args... args) -> Ret {
auto self = reinterpret_cast<EventOwner<NbEvents>*>(*opaque);
assert(self->callbacks[Idx].get());
auto cbHandler = static_cast<CallbackHandler<Func>*>( self->callbacks[Idx].get() );
return cbHandler->func( std::forward<Args>(args)... );
};
}
};
// Specialization to handle null callbacks at build time.
// We could try to compare any "Func" against nullptr at runtime, though
// since Func is a template type, which roughly has to satisfy the "Callable" concept,
// it could be an instance of a function object, which doesn't compare nicely against nullptr.
// Using the specialization at build time is easier and performs better.
template <int Idx, typename... Args>
struct CallbackWrapper<Idx, std::nullptr_t, void(*)(void*, Args...)>
{
template <int NbEvents>
static std::nullptr_t wrap(EventOwner<NbEvents>*, std::nullptr_t)
{
return nullptr;
}
};
}
#endif
test/main.cpp
View file @ 7497299f
......@@ -24,6 +24,7 @@
#include <iostream>
#include <thread>
#include <cstring>
int main(int ac, char** av)
{
......@@ -41,10 +42,34 @@ int main(int ac, char** av)
std::cout << media.mrl() << " is playing" << std::endl;
});
auto imgBuffer = malloc(480 * 320 * 4);
mp.setVideoCallbacks([imgBuffer](void** pBuffer) -> void* {
std::cout << "Lock" << std::endl;
*pBuffer = imgBuffer;
return NULL;
}, [](void*, void*const*) {
std::cout << "unlock" << std::endl;
}, nullptr);
mp.setVideoFormatCallbacks([](char* chroma, uint32_t* width, uint32_t* height, uint32_t* pitch, uint32_t* lines) -> int {
memcpy(chroma, "RV32", 4);
*width = 480;
*height = 320;
*pitch = *width * 4;
*lines = 320;
return 1;
}, nullptr);
mp.play();
bool expected = true;
mp.setAudioCallbacks([](const void*, uint32_t count, int64_t pts) {
std::cout << "Playing " << count << " samples at pts " << pts << std::endl;
}, nullptr, nullptr, nullptr, nullptr
);
auto& handler = mp.eventManager().onPositionChanged([&expected](float pos) {
std::cout << "position changed " << pos << std::endl;
assert(expected);
......@@ -111,4 +136,5 @@ int main(int ac, char** av)
{
std::cout << f.name() << std::endl;
}
free(imgBuffer);
}
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