1 #ifndef _FFMPEG_CAPTURE_H
2 #define _FFMPEG_CAPTURE_H 1
4 // FFmpegCapture looks much like a capture card, but the frames it spits out
5 // come from a video in real time, looping. Because it decodes the video using
6 // FFmpeg (thus the name), this means it can handle a very wide array of video
7 // formats, and also things like network streaming and V4L capture, but it is
8 // also significantly less integrated and optimized than the regular capture
9 // cards. In particular, the frames are always scaled and converted to 8-bit
10 // RGBA on the CPU before being sent on to the GPU.
12 // Since we don't really know much about the video when building the chains,
13 // there are some limitations. In particular, frames are always assumed to be
14 // sRGB even if the video container says something else. We could probably
15 // try to load the video on startup and pick out the parameters at that point
16 // (which would probably also allow us to send Y'CbCr video through without
17 // CPU conversion), but it would require some more plumbing, and it would also
18 // fail if the file changes parameters midway, which is allowed in some formats.
20 // There is currently no audio support. There is also no support for changing
21 // the video underway (unlike images), although there really should be.
22 // Finally, there is currently no support for controlling the video from Lua.
34 #include "bmusb/bmusb.h"
36 class FFmpegCapture : public bmusb::CaptureInterface
39 FFmpegCapture(const std::string &filename, unsigned width, unsigned height);
42 void set_card_index(int card_index)
44 this->card_index = card_index;
47 int get_card_index() const
54 std::lock_guard<std::mutex> lock(queue_mu);
55 command_queue.push_back(QueuedCommand { QueuedCommand::REWIND });
59 void set_video_frame_allocator(bmusb::FrameAllocator *allocator) override
61 video_frame_allocator = allocator;
62 if (owned_video_frame_allocator.get() != allocator) {
63 owned_video_frame_allocator.reset();
67 bmusb::FrameAllocator *get_video_frame_allocator() override
69 return video_frame_allocator;
72 // Does not take ownership.
73 void set_audio_frame_allocator(bmusb::FrameAllocator *allocator) override
75 audio_frame_allocator = allocator;
76 if (owned_audio_frame_allocator.get() != allocator) {
77 owned_audio_frame_allocator.reset();
81 bmusb::FrameAllocator *get_audio_frame_allocator() override
83 return audio_frame_allocator;
86 void set_frame_callback(bmusb::frame_callback_t callback) override
88 frame_callback = callback;
91 void set_dequeue_thread_callbacks(std::function<void()> init, std::function<void()> cleanup) override
93 dequeue_init_callback = init;
94 dequeue_cleanup_callback = cleanup;
95 has_dequeue_callbacks = true;
98 std::string get_description() const override
103 void configure_card() override;
104 void start_bm_capture() override;
105 void stop_dequeue_thread() override;
107 // TODO: Specify error status through this.
108 bool get_disconnected() const override { return false; }
110 std::map<uint32_t, bmusb::VideoMode> get_available_video_modes() const;
111 void set_video_mode(uint32_t video_mode_id) override {} // Ignore.
112 uint32_t get_current_video_mode() const override { return 0; }
114 std::set<bmusb::PixelFormat> get_available_pixel_formats() const override {
115 return std::set<bmusb::PixelFormat>{ bmusb::PixelFormat_8BitRGBA };
117 void set_pixel_format(bmusb::PixelFormat pixel_format) override {
118 assert(pixel_format == bmusb::PixelFormat_8BitRGBA);
120 bmusb::PixelFormat get_current_pixel_format() const override {
121 return bmusb::PixelFormat_8BitRGBA;
124 std::map<uint32_t, std::string> get_available_video_inputs() const override {
125 return { { 0, "Auto" } }; }
126 void set_video_input(uint32_t video_input_id) override {} // Ignore.
127 uint32_t get_current_video_input() const override { return 0; }
129 std::map<uint32_t, std::string> get_available_audio_inputs() const override {
130 return { { 0, "Embedded" } };
132 void set_audio_input(uint32_t audio_input_id) override {} // Ignore.
133 uint32_t get_current_audio_input() const override { return 0; }
136 void producer_thread_func();
137 bool play_video(const std::string &pathname);
139 std::string description, filename;
140 uint16_t timecode = 0;
141 unsigned width, height;
142 bool running = false;
145 bool has_dequeue_callbacks = false;
146 std::function<void()> dequeue_init_callback = nullptr;
147 std::function<void()> dequeue_cleanup_callback = nullptr;
149 bmusb::FrameAllocator *video_frame_allocator = nullptr;
150 bmusb::FrameAllocator *audio_frame_allocator = nullptr;
151 std::unique_ptr<bmusb::FrameAllocator> owned_video_frame_allocator;
152 std::unique_ptr<bmusb::FrameAllocator> owned_audio_frame_allocator;
153 bmusb::frame_callback_t frame_callback = nullptr;
155 std::atomic<bool> producer_thread_should_quit{false};
156 std::thread producer_thread;
159 struct QueuedCommand {
160 enum Command { REWIND } command;
162 std::vector<QueuedCommand> command_queue; // Protected by <queue_mu>.
165 #endif // !defined(_FFMPEG_CAPTURE_H)