avformat/dashenc: Persistent HTTP connections supported as an option

Reviewed-by: Aman Gupta <aman@tmm1.net> Reviewed-by: Steven Liu <lq@onvideo.cn>
7 years ago · 0c78b6a416
parent e8f71ef338
commit 0c78b6a416
2 changed files with 56 additions and 13 deletions
--- a/doc/muxers.texi
+++ b/doc/muxers.texi
@ -249,6 +249,8 @@ DASH-templated name to used for the media segments. Default is "chunk-stream$Rep
 URL of the page that will return the UTC timestamp in ISO format. Example: "https://time.akamai.com/?iso"
@item -http_user_agent @var{user_agent}
 Override User-Agent field in HTTP header. Applicable only for HTTP output.
+@item -http_persistent @var{http_persistent}
+Use persistent HTTP connections. Applicable only for HTTP output.
@item -hls_playlist @var{hls_playlist}
 Generate HLS playlist files as well. The master playlist is generated with the filename master.m3u8.
 One media playlist file is generated for each stream with filenames media_0.m3u8, media_1.m3u8, etc.
--- a/libavformat/dashenc.c
+++ b/libavformat/dashenc.c
@ -37,6 +37,9 @@
 #include "avformat.h"
 #include "avio_internal.h"
 #include "hlsplaylist.h"
+#if CONFIG_HTTP_PROTOCOL
+#include "http.h"
+#endif
 #include "internal.h"
 #include "isom.h"
 #include "os_support.h"
@ -103,7 +106,10 @@ typedef struct DASHContext {
    const char *utc_timing_url;
    const char *user_agent;
    int hls_playlist;
+    int http_persistent;
    int master_playlist_created;
+    AVIOContext *mpd_out;
+    AVIOContext *m3u8_out;
 } DASHContext;

 static struct codec_string {
@ -117,6 +123,36 @@ static struct codec_string {
    { 0, NULL }
 };

+static int dashenc_io_open(AVFormatContext *s, AVIOContext **pb, char *filename,
+                           AVDictionary **options) {
+    DASHContext *c = s->priv_data;
+    int http_base_proto = filename ? ff_is_http_proto(filename) : 0;
+    int err = AVERROR_MUXER_NOT_FOUND;
+    if (!*pb || !http_base_proto || !c->http_persistent) {
+        err = s->io_open(s, pb, filename, AVIO_FLAG_WRITE, options);
+#if CONFIG_HTTP_PROTOCOL
+    } else {
+        URLContext *http_url_context = ffio_geturlcontext(*pb);
+        av_assert0(http_url_context);
+        err = ff_http_do_new_request(http_url_context, filename);
+#endif
+    }
+    return err;
+}
+
+static void dashenc_io_close(AVFormatContext *s, AVIOContext **pb, char *filename) {
+    DASHContext *c = s->priv_data;
+    int http_base_proto = filename ? ff_is_http_proto(filename) : 0;
+
+    if (!http_base_proto || !c->http_persistent) {
+        ff_format_io_close(s, pb);
+#if CONFIG_HTTP_PROTOCOL
+    } else {
+        avio_flush(*pb);
+#endif
+    }
+}
+
 static void set_codec_str(AVFormatContext *s, AVCodecParameters *par,
                          char *str, int size)
 {
@ -218,6 +254,8 @@ static void set_http_options(AVDictionary **options, DASHContext *c)
 {
    if (c->user_agent)
        av_dict_set(options, "user_agent", c->user_agent, 0);
+    if (c->http_persistent)
+        av_dict_set_int(options, "multiple_requests", 1, 0);
 }

 static void get_hls_playlist_name(char *playlist_name, int string_size,
@ -273,9 +311,10 @@ static void dash_free(AVFormatContext *s)
    av_freep(&c->streams);
 }

-static void output_segment_list(OutputStream *os, AVIOContext *out, DASHContext *c,
+static void output_segment_list(OutputStream *os, AVIOContext *out, AVFormatContext *s,
                                int representation_id, int final)
 {
+    DASHContext *c = s->priv_data;
    int i, start_index = 0, start_number = 1;
    if (c->window_size) {
        start_index  = FFMAX(os->nb_segments   - c->window_size, 0);
@ -339,7 +378,6 @@ static void output_segment_list(OutputStream *os, AVIOContext *out, DASHContext
        int timescale = os->ctx->streams[0]->time_base.den;
        char temp_filename_hls[1024];
        char filename_hls[1024];
-        AVIOContext *out_hls = NULL;
        AVDictionary *http_opts = NULL;
        int target_duration = 0;
        int ret = 0;
@ -352,7 +390,7 @@ static void output_segment_list(OutputStream *os, AVIOContext *out, DASHContext
        snprintf(temp_filename_hls, sizeof(temp_filename_hls), use_rename ? "%s.tmp" : "%s", filename_hls);

        set_http_options(&http_opts, c);
-        avio_open2(&out_hls, temp_filename_hls, AVIO_FLAG_WRITE, NULL, &http_opts);
+        dashenc_io_open(s, &c->m3u8_out, temp_filename_hls, &http_opts);
        av_dict_free(&http_opts);
        for (i = start_index; i < os->nb_segments; i++) {
            Segment *seg = os->segments[i];
@ -361,15 +399,15 @@ static void output_segment_list(OutputStream *os, AVIOContext *out, DASHContext
                target_duration = lrint(duration);
        }

-        ff_hls_write_playlist_header(out_hls, 6, -1, target_duration,
+        ff_hls_write_playlist_header(c->m3u8_out, 6, -1, target_duration,
                                     start_number, PLAYLIST_TYPE_NONE);

-        ff_hls_write_init_file(out_hls, os->initfile, c->single_file,
+        ff_hls_write_init_file(c->m3u8_out, os->initfile, c->single_file,
                               os->init_range_length, os->init_start_pos);

        for (i = start_index; i < os->nb_segments; i++) {
            Segment *seg = os->segments[i];
-            ret = ff_hls_write_file_entry(out_hls, 0, c->single_file,
+            ret = ff_hls_write_file_entry(c->m3u8_out, 0, c->single_file,
                                    (double) seg->duration / timescale, 0,
                                    seg->range_length, seg->start_pos, NULL,
                                    c->single_file ? os->initfile : seg->file,
@ -380,9 +418,10 @@ static void output_segment_list(OutputStream *os, AVIOContext *out, DASHContext
        }

        if (final)
-            ff_hls_write_end_list(out_hls);
+            ff_hls_write_end_list(c->m3u8_out);
+
+        dashenc_io_close(s, &c->m3u8_out, temp_filename_hls);

-        avio_close(out_hls);
        if (use_rename)
            if (avpriv_io_move(temp_filename_hls, filename_hls) < 0) {
                av_log(os->ctx, AV_LOG_WARNING, "renaming file %s to %s failed\n\n", temp_filename_hls, filename_hls);
@ -498,7 +537,7 @@ static int write_adaptation_set(AVFormatContext *s, AVIOContext *out, int as_ind
            avio_printf(out, "\t\t\t\t<AudioChannelConfiguration schemeIdUri=\"urn:mpeg:dash:23003:3:audio_channel_configuration:2011\" value=\"%d\" />\n",
                s->streams[i]->codecpar->channels);
        }
-        output_segment_list(os, out, c, i, final);
+        output_segment_list(os, out, s, i, final);
        avio_printf(out, "\t\t\t</Representation>\n");
    }
    avio_printf(out, "\t\t</AdaptationSet>\n");
@ -657,11 +696,12 @@ static int write_manifest(AVFormatContext *s, int final)

    snprintf(temp_filename, sizeof(temp_filename), use_rename ? "%s.tmp" : "%s", s->filename);
    set_http_options(&opts, c);
-    ret = s->io_open(s, &out, temp_filename, AVIO_FLAG_WRITE, &opts);
+    ret = dashenc_io_open(s, &c->mpd_out, temp_filename, &opts);
    if (ret < 0) {
        av_log(s, AV_LOG_ERROR, "Unable to open %s for writing\n", temp_filename);
        return ret;
    }
+    out = c->mpd_out;
    av_dict_free(&opts);
    avio_printf(out, "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n");
    avio_printf(out, "<MPD xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\n"
@ -728,7 +768,7 @@ static int write_manifest(AVFormatContext *s, int final)

    avio_printf(out, "</MPD>\n");
    avio_flush(out);
-    ff_format_io_close(s, &out);
+    dashenc_io_close(s, &c->mpd_out, temp_filename);

    if (use_rename) {
        if ((ret = avpriv_io_move(temp_filename, s->filename)) < 0)
@ -1115,7 +1155,7 @@ static int dash_flush(AVFormatContext *s, int final, int stream)
            snprintf(full_path, sizeof(full_path), "%s%s", c->dirname, filename);
            snprintf(temp_path, sizeof(temp_path), use_rename ? "%s.tmp" : "%s", full_path);
            set_http_options(&opts, c);
-            ret = s->io_open(s, &os->out, temp_path, AVIO_FLAG_WRITE, &opts);
+            ret = dashenc_io_open(s, &os->out, temp_path, &opts);
            if (ret < 0)
                break;
            av_dict_free(&opts);
@ -1133,7 +1173,7 @@ static int dash_flush(AVFormatContext *s, int final, int stream)
        if (c->single_file) {
            find_index_range(s, full_path, os->pos, &index_length);
        } else {
-            ff_format_io_close(s, &os->out);
+            dashenc_io_close(s, &os->out, temp_path);

            if (use_rename) {
                ret = avpriv_io_move(temp_path, full_path);
@ -1330,6 +1370,7 @@ static const AVOption options[] = {
    { "media_seg_name", "DASH-templated name to used for the media segments", OFFSET(media_seg_name), AV_OPT_TYPE_STRING, {.str = "chunk-stream$RepresentationID$-$Number%05d$.m4s"}, 0, 0, E },
    { "utc_timing_url", "URL of the page that will return the UTC timestamp in ISO format", OFFSET(utc_timing_url), AV_OPT_TYPE_STRING, { 0 }, 0, 0, E },
    { "http_user_agent", "override User-Agent field in HTTP header", OFFSET(user_agent), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, E},
+    { "http_persistent", "Use persistent HTTP connections", OFFSET(http_persistent), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, E },
    { "hls_playlist", "Generate HLS playlist files(master.m3u8, media_%d.m3u8)", OFFSET(hls_playlist), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, E },
    { NULL },
 };