Start a mux only on a keyframe, so that transcoding clients do not get too confused.

[nageru] / httpd.cpp

diff --git a/httpd.cpp b/httpd.cpp
index 29923f9430413ee5dec3175e0aaae42a7f257cf1..6a92699936c45ef3a0c324064512af69abd2d2b8 100644 (file)
--- a/httpd.cpp
+++ b/httpd.cpp
@@ -14,6 +14,8 @@ extern "C" {
 #include <libavutil/samplefmt.h>
 }
 
+#include <vector>
+
 #include "httpd.h"
 
 #include "defs.h"
@@ -34,11 +36,14 @@ void HTTPD::start(int port)
        MHD_start_daemon(MHD_USE_THREAD_PER_CONNECTION | MHD_USE_POLL_INTERNALLY | MHD_USE_DUAL_STACK,
                         port,
                         nullptr, nullptr,
-                        &answer_to_connection_thunk, this, MHD_OPTION_END);
+                        &answer_to_connection_thunk, this,
+                        MHD_OPTION_NOTIFY_COMPLETED, &request_completed_thunk, this, 
+                        MHD_OPTION_END);
 }
 
 void HTTPD::add_packet(const AVPacket &pkt, int64_t pts, int64_t dts)
 {
+       unique_lock<mutex> lock(streams_mutex);
        for (Stream *stream : streams) {
                stream->add_packet(pkt, pts, dts);
        }
@@ -51,6 +56,7 @@ void HTTPD::open_output_file(const string &filename)
 {
        AVFormatContext *avctx = avformat_alloc_context();
        avctx->oformat = av_guess_format(NULL, filename.c_str(), NULL);
+       assert(filename.size() < sizeof(avctx->filename) - 1);
        strcpy(avctx->filename, filename.c_str());
 
        string url = "file:" + filename;
@@ -83,11 +89,14 @@ int HTTPD::answer_to_connection(MHD_Connection *connection,
                                const char *version, const char *upload_data,
                                size_t *upload_data_size, void **con_cls)
 {
-       printf("url %s\n", url);
        AVOutputFormat *oformat = av_guess_format(STREAM_MUX_NAME, nullptr, nullptr);
        assert(oformat != nullptr);
        HTTPD::Stream *stream = new HTTPD::Stream(oformat, width, height);
-       streams.push_back(stream);
+       {
+               unique_lock<mutex> lock(streams_mutex);
+               streams.insert(stream);
+       }
+       *con_cls = stream;
 
        // Does not strictly have to be equal to MUX_BUFFER_SIZE.
        MHD_Response *response = MHD_create_response_from_callback(
@@ -100,10 +109,32 @@ int HTTPD::answer_to_connection(MHD_Connection *connection,
 
 void HTTPD::free_stream(void *cls)
 {
+       // FIXME: When is this actually called, if ever?
+       // Also, shouldn't we remove it from streams?
        HTTPD::Stream *stream = (HTTPD::Stream *)cls;
        delete stream;
 }
 
+void HTTPD::request_completed_thunk(void *cls, struct MHD_Connection *connection, void **con_cls, enum MHD_RequestTerminationCode toe)
+{
+       HTTPD *httpd = (HTTPD *)cls;
+       return httpd->request_completed(connection, con_cls, toe);
+}
+
+void HTTPD::request_completed(struct MHD_Connection *connection, void **con_cls, enum MHD_RequestTerminationCode toe)
+{
+       if (con_cls == nullptr) {
+               // Request was never set up.
+               return;
+       }
+       HTTPD::Stream *stream = (HTTPD::Stream *)*con_cls;
+       {
+               unique_lock<mutex> lock(streams_mutex);
+               delete stream;
+               streams.erase(stream);
+       }
+}
+
 HTTPD::Mux::Mux(AVFormatContext *avctx, int width, int height)
        : avctx(avctx)
 {
@@ -114,6 +145,8 @@ HTTPD::Mux::Mux(AVFormatContext *avctx, int width, int height)
                exit(1);
        }
        avstream_video->time_base = AVRational{1, TIMEBASE};
+       avstream_video->codec->codec_type = AVMEDIA_TYPE_VIDEO;
+       avstream_video->codec->codec_id = AV_CODEC_ID_H264;
        avstream_video->codec->width = width;
        avstream_video->codec->height = height;
        avstream_video->codec->time_base = AVRational{1, TIMEBASE};
@@ -163,6 +196,12 @@ HTTPD::Mux::~Mux()
 
 void HTTPD::Mux::add_packet(const AVPacket &pkt, int64_t pts, int64_t dts)
 {
+       if (!seen_keyframe && !(pkt.stream_index == 0 && (pkt.flags & AV_PKT_FLAG_KEY))) {
+               // Wait until we see the first (video) key frame.
+               return;
+       }
+       seen_keyframe = true;
+
        AVPacket pkt_copy;
        av_copy_packet(&pkt_copy, &pkt);
        if (pkt.stream_index == 0) {