X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=mux.h;h=e6193e0a36c92ec0258f3680df597a37f15ce26f;hb=e284d1c7a2e18ee7e4aea082c4a57a3504a0f5e8;hp=c6c442100c58b18c481754747693b54c8571bcbc;hpb=bc0683200d63d2fd0d49c0b998885c8b4d9db77e;p=nageru diff --git a/mux.h b/mux.h index c6c4421..e6193e0 100644 --- a/mux.h +++ b/mux.h @@ -10,12 +10,16 @@ extern "C" { #include #include +#include #include #include #include #include +#include #include +#include "timebase.h" + struct MuxMetrics { // “written” will usually be equal video + audio + mux overhead, // except that there could be buffered packets that count in audio or video @@ -39,15 +43,26 @@ public: CODEC_H264, CODEC_NV12, // Uncompressed 4:2:0. }; + enum WriteStrategy { + // add_packet() will write the packet immediately, unless plugged. + WRITE_FOREGROUND, + + // All writes will happen on a separate thread, so add_packet() + // won't block. Use this if writing to a file and you might be + // holding a mutex (because blocking I/O with a mutex held is + // not good). Note that this will clone every packet, so it has + // higher overhead. + WRITE_BACKGROUND, + }; // Takes ownership of avctx. will be called every time // a write has been made to the video stream (id 0), with the pts of // the just-written frame. (write_callback can be nullptr.) // Does not take ownership of ; elements in there, if any, // will be added to. - Mux(AVFormatContext *avctx, int width, int height, Codec video_codec, const std::string &video_extradata, const AVCodecParameters *audio_codecpar, int time_base, std::function write_callback, const std::vector &metrics); + Mux(AVFormatContext *avctx, int width, int height, Codec video_codec, const std::string &video_extradata, const AVCodecParameters *audio_codecpar, int time_base, std::function write_callback, WriteStrategy write_strategy, const std::vector &metrics); ~Mux(); - void add_packet(const AVPacket &pkt, int64_t pts, int64_t dts); + void add_packet(const AVPacket &pkt, int64_t pts, int64_t dts, AVRational timebase = { 1, TIMEBASE }); // As long as the mux is plugged, it will not actually write anything to disk, // just queue the packets. Once it is unplugged, the packets are reordered by pts @@ -61,17 +76,36 @@ public: void unplug(); private: - void write_packet_or_die(const AVPacket &pkt); // Must be called with held. + // If write_strategy == WRITE_FOREGORUND, Must be called with held. + void write_packet_or_die(const AVPacket &pkt, int64_t unscaled_pts); + void thread_func(); + + WriteStrategy write_strategy; std::mutex mu; - AVFormatContext *avctx; // Protected by . + + // These are only in use if write_strategy == WRITE_BACKGROUND. + std::atomic writer_thread_should_quit{false}; + std::thread writer_thread; + + AVFormatContext *avctx; // Protected by , iff write_strategy == WRITE_BACKGROUND. int plug_count = 0; // Protected by . - std::vector plugged_packets; // Protected by . + + // Protected by . If write_strategy == WRITE_FOREGROUND, + // this is only in use when plugging. + struct QueuedPacket { + AVPacket *pkt; + int64_t unscaled_pts; + }; + std::vector packet_queue; + std::condition_variable packet_queue_ready; AVStream *avstream_video, *avstream_audio; std::function write_callback; std::vector metrics; + + friend struct PacketBefore; }; #endif // !defined(_MUX_H)