From 1aed35035690e236623d5a1d9dde9b2bb92d4e11 Mon Sep 17 00:00:00 2001
From: Kamil Trzcinski <ayufan@ayufan.eu>
Date: Wed, 6 Apr 2022 22:02:58 +0200
Subject: [PATCH] Reduce buffering for mkv/mp4

---
 cmd/main.c         |  1 +
 http/http.h        |  2 ++
 http/http_ffmpeg.c | 25 ++++++++++++++++++++++++-
 3 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/cmd/main.c b/cmd/main.c
index 62707cf..771ce60 100644
--- a/cmd/main.c
+++ b/cmd/main.c
@@ -17,6 +17,7 @@ http_method_t http_methods[] = {
   { "GET /video?", http_video_html },
   { "GET /video.h264?", http_h264_video },
   { "GET /video.mkv?", http_mkv_video },
+  { "GET /video.mp4?", http_mp4_video },
   { "GET /jmuxer.min.js?", http_jmuxer_js },
   { "GET /?", http_index },
   { }
diff --git a/http/http.h b/http/http.h
index 02925d6..fac1b64 100644
--- a/http/http.h
+++ b/http/http.h
@@ -54,3 +54,5 @@ bool http_h264_needs_buffer();
 void http_h264_capture(buffer_t *buf);
 void http_h264_video(http_worker_t *worker, FILE *stream);
 void http_mkv_video(http_worker_t *worker, FILE *stream);
+void http_mp4_video(http_worker_t *worker, FILE *stream);
+void http_mov_video(http_worker_t *worker, FILE *stream);
diff --git a/http/http_ffmpeg.c b/http/http_ffmpeg.c
index 8918ff1..6d49922 100644
--- a/http/http_ffmpeg.c
+++ b/http/http_ffmpeg.c
@@ -33,6 +33,7 @@ typedef struct {
   AVIOContext *output_avio;
   AVFormatContext *output_context;
   AVPacket *packet;
+  AVDictionary *output_opts;
 
   bool had_key_frame;
   bool requested_key_frame;
@@ -43,6 +44,7 @@ typedef struct {
   int pts;
   buffer_t *buf;
   unsigned buf_offset;
+  unsigned stream_offset;
 } http_ffmpeg_status_t;
 
 static int http_ffmpeg_read_from_buf(void *opaque, uint8_t *buf, int buf_size)
@@ -55,6 +57,7 @@ static int http_ffmpeg_read_from_buf(void *opaque, uint8_t *buf, int buf_size)
   if (!buf_size)
     return AVERROR_EOF;
 
+  E_LOG_DEBUG(status, "http_ffmpeg_read_from_buf: offset=%d, n=%d", status->buf_offset, buf_size);
   memcpy(buf, (char*)status->buf->start + status->buf_offset, buf_size);
   status->buf_offset += buf_size;
   return buf_size;
@@ -72,6 +75,11 @@ static int http_ffmpeg_write_to_stream(void *opaque, uint8_t *buf, int buf_size)
   }
 
   size_t n = fwrite(buf, 1, buf_size, status->stream);
+  fflush(status->stream);
+
+  E_LOG_DEBUG(status, "http_ffmpeg_write_to_stream: offset=%d, n=%d, buf_size=%d, error=%d",
+    status->stream_offset, buf_size, ferror(status->stream));
+  status->stream_offset += n;
   if (ferror(status->stream))
     return AVERROR_EOF;
 
@@ -155,6 +163,8 @@ static int http_ffmpeg_open_status(http_ffmpeg_status_t *status)
 
   if (status->packet)
     return 0;
+    
+
 
   status->packet = av_packet_alloc();
   if (!status->packet)
@@ -169,7 +179,7 @@ static int http_ffmpeg_open_status(http_ffmpeg_status_t *status)
     return ret;
   if ((ret = http_ffmpeg_copy_streams(status)) < 0)
     return ret;
-  if ((ret = avformat_write_header(status->output_context, NULL)) < 0)
+  if ((ret = avformat_write_header(status->output_context, &status->output_opts)) < 0)
     return ret;
 
   status->start_time = get_monotonic_time_us(NULL, NULL);
@@ -182,6 +192,7 @@ static int http_ffmpeg_close_status(http_ffmpeg_status_t *status)
   http_ffmpeg_close_avcontext(&status->input_context);
   http_ffmpeg_close_avcontext(&status->output_context);
   av_packet_free(&status->packet);
+  av_dict_free(&status->output_opts);
 }
 
 static int http_ffmpeg_copy_packets(http_ffmpeg_status_t *status)
@@ -276,6 +287,13 @@ static void http_ffmpeg_video(http_worker_t *worker, FILE *stream, const char *c
     .video_format = video_format
   };
 
+  av_dict_set_int(&status.output_opts, "probesize", 4096, 0);
+  av_dict_set_int(&status.output_opts, "direct", 1, 0);
+  av_dict_set_int(&status.output_opts, "frag_duration", 0, 0);
+  av_dict_set_int(&status.output_opts, "low_delay", 1, 0);
+  av_dict_set_int(&status.output_opts, "nobuffer", 1, 0);
+  av_dict_set_int(&status.output_opts, "flush_packets", 1, 0);
+
   int n = buffer_lock_write_loop(&http_h264, 0, (buffer_write_fn)http_ffmpeg_video_buf_part, &status);
   http_ffmpeg_close_status(&status);
 
@@ -296,3 +314,8 @@ void http_mkv_video(http_worker_t *worker, FILE *stream)
 {
   http_ffmpeg_video(worker, stream, "video/mp4", "matroska");
 }
+
+void http_mp4_video(http_worker_t *worker, FILE *stream)
+{
+  http_ffmpeg_video(worker, stream, "video/mp4", "mp4");
+}