[FFmpeg-devel] [PATCH 2/2] avformat/dashenc: Add support for Global SIDX

Karthick J kjeyapal at akamai.com
Sun Mar 24 14:30:22 EET 2019


---
 doc/muxers.texi       |   3 ++
 libavformat/dashenc.c | 119 ++++++++++++++++++++++++++++--------------
 2 files changed, 84 insertions(+), 38 deletions(-)

diff --git a/doc/muxers.texi b/doc/muxers.texi
index aac7d94edf..83ae017d6c 100644
--- a/doc/muxers.texi
+++ b/doc/muxers.texi
@@ -293,6 +293,9 @@ Set container format (mp4/webm) options using a @code{:} separated list of
 key=value parameters. Values containing @code{:} special characters must be
 escaped.
 
+ at item -global_sidx @var{global_sidx}
+Write global SIDX atom. Applicable only for single file, mp4 output, non-streaming mode.
+
 @item -dash_segment_type @var{dash_segment_type}
 Possible values:
 @item auto
diff --git a/libavformat/dashenc.c b/libavformat/dashenc.c
index 1b74bce060..f8d71166d4 100644
--- a/libavformat/dashenc.c
+++ b/libavformat/dashenc.c
@@ -140,6 +140,7 @@ typedef struct DASHContext {
     int64_t timeout;
     int index_correction;
     char *format_options_str;
+    int global_sidx;
     SegmentType segment_type_option;  /* segment type as specified in options */
     int ignore_io_errors;
     int lhls;
@@ -368,7 +369,7 @@ static void set_codec_str(AVFormatContext *s, AVCodecParameters *par,
     }
 }
 
-static int flush_dynbuf(OutputStream *os, int *range_length)
+static int flush_dynbuf(DASHContext *c, OutputStream *os, int *range_length)
 {
     uint8_t *buffer;
 
@@ -380,16 +381,21 @@ static int flush_dynbuf(OutputStream *os, int *range_length)
     av_write_frame(os->ctx, NULL);
     avio_flush(os->ctx->pb);
 
-    // write out to file
-    *range_length = avio_close_dyn_buf(os->ctx->pb, &buffer);
-    os->ctx->pb = NULL;
-    if (os->out)
-        avio_write(os->out, buffer + os->written_len, *range_length - os->written_len);
-    os->written_len = 0;
-    av_free(buffer);
-
-    // re-open buffer
-    return avio_open_dyn_buf(&os->ctx->pb);
+    if (!c->single_file) {
+        // write out to file
+        *range_length = avio_close_dyn_buf(os->ctx->pb, &buffer);
+        os->ctx->pb = NULL;
+        if (os->out)
+            avio_write(os->out, buffer + os->written_len, *range_length - os->written_len);
+        os->written_len = 0;
+        av_free(buffer);
+
+        // re-open buffer
+        return avio_open_dyn_buf(&os->ctx->pb);
+    } else {
+        *range_length = avio_tell(os->ctx->pb) - os->pos;
+        return 0;
+    }
 }
 
 static void set_http_options(AVDictionary **options, DASHContext *c)
@@ -508,7 +514,7 @@ static int flush_init_segment(AVFormatContext *s, OutputStream *os)
     DASHContext *c = s->priv_data;
     int ret, range_length;
 
-    ret = flush_dynbuf(os, &range_length);
+    ret = flush_dynbuf(c, os, &range_length);
     if (ret < 0)
         return ret;
 
@@ -537,8 +543,12 @@ static void dash_free(AVFormatContext *s)
         return;
     for (i = 0; i < s->nb_streams; i++) {
         OutputStream *os = &c->streams[i];
-        if (os->ctx && os->ctx->pb)
-            ffio_free_dyn_buf(&os->ctx->pb);
+        if (os->ctx && os->ctx->pb) {
+            if (!c->single_file)
+                ffio_free_dyn_buf(&os->ctx->pb);
+            else
+                avio_close(os->ctx->pb);
+        }
         ff_format_io_close(s, &os->out);
         if (os->ctx)
             avformat_free_context(os->ctx);
@@ -1106,6 +1116,16 @@ static int dash_init(AVFormatContext *s)
         c->lhls = 0;
     }
 
+    if (c->global_sidx && !c->single_file) {
+        av_log(s, AV_LOG_WARNING, "Global SIDX option will be ignored as single_file is not enabled\n");
+        c->global_sidx = 0;
+    }
+
+    if (c->global_sidx && c->streaming) {
+        av_log(s, AV_LOG_WARNING, "Global SIDX option will be ignored as streaming is enabled\n");
+        c->global_sidx = 0;
+    }
+
     av_strlcpy(c->dirname, s->url, sizeof(c->dirname));
     ptr = strrchr(c->dirname, '/');
     if (ptr) {
@@ -1201,9 +1221,6 @@ static int dash_init(AVFormatContext *s)
         ctx->avoid_negative_ts = s->avoid_negative_ts;
         ctx->flags = s->flags;
 
-        if ((ret = avio_open_dyn_buf(&ctx->pb)) < 0)
-            return ret;
-
         if (c->single_file) {
             if (os->single_file_name)
                 ff_dash_fill_tmpl_params(os->initfile, sizeof(os->initfile), os->single_file_name, i, 0, os->bit_rate, 0);
@@ -1214,7 +1231,14 @@ static int dash_init(AVFormatContext *s)
         }
         snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->initfile);
         set_http_options(&opts, c);
-        ret = s->io_open(s, &os->out, filename, AVIO_FLAG_WRITE, &opts);
+        if (!c->single_file) {
+            if ((ret = avio_open_dyn_buf(&ctx->pb)) < 0)
+                return ret;
+            ret = s->io_open(s, &os->out, filename, AVIO_FLAG_WRITE, &opts);
+        } else {
+            ctx->url = av_strdup(filename);
+            ret = avio_open2(&ctx->pb, filename, AVIO_FLAG_WRITE, NULL, &opts);
+        }
         av_dict_free(&opts);
         if (ret < 0)
             return ret;
@@ -1232,8 +1256,12 @@ static int dash_init(AVFormatContext *s)
                 // skip_sidx : Reduce bitrate overhead
                 // skip_trailer : Avoids growing memory usage with time
                 av_dict_set(&opts, "movflags", "frag_every_frame+dash+delay_moov+skip_sidx+skip_trailer", 0);
-            else
-                av_dict_set(&opts, "movflags", "frag_custom+dash+delay_moov", 0);
+            else {
+                if (c->global_sidx)
+                    av_dict_set(&opts, "movflags", "frag_custom+dash+delay_moov+global_sidx+skip_trailer", 0);
+                else
+                    av_dict_set(&opts, "movflags", "frag_custom+dash+delay_moov+skip_trailer", 0);
+            }
         } else {
             av_dict_set_int(&opts, "cluster_time_limit", c->seg_duration / 1000, 0);
             av_dict_set_int(&opts, "cluster_size_limit", 5 * 1024 * 1024, 0); // set a large cluster size limit
@@ -1518,7 +1546,7 @@ static int dash_flush(AVFormatContext *s, int final, int stream)
             snprintf(os->full_path, sizeof(os->full_path), "%s%s", c->dirname, os->initfile);
         }
 
-        ret = flush_dynbuf(os, &range_length);
+        ret = flush_dynbuf(c, os, &range_length);
         if (ret < 0)
             break;
         os->packets_written = 0;
@@ -1565,6 +1593,29 @@ static int dash_flush(AVFormatContext *s, int final, int stream)
         }
     }
 
+    if (final) {
+        for (i = 0; i < s->nb_streams; i++) {
+            OutputStream *os = &c->streams[i];
+            if (os->ctx && os->ctx_inited) {
+                int file_size = avio_tell(os->ctx->pb);
+                av_write_trailer(os->ctx);
+                if (c->global_sidx) {
+                    int j, start_index, start_number;
+                    int sidx_size = avio_tell(os->ctx->pb) - file_size;
+                    get_start_index_number(os, c, &start_index, &start_number);
+                    if (start_index >= os->nb_segments ||
+                        os->segment_type != SEGMENT_TYPE_MP4)
+                        continue;
+                    os->init_range_length += sidx_size;
+                    for (j = start_index; j < os->nb_segments; j++) {
+                        Segment *seg = os->segments[j];
+                        seg->start_pos += sidx_size;
+                    }
+                }
+
+            }
+        }
+    }
     if (ret >= 0)
         ret = write_manifest(s, final);
     return ret;
@@ -1735,30 +1786,21 @@ static int dash_write_trailer(AVFormatContext *s)
     }
     dash_flush(s, 1, -1);
 
-    for (i = 0; i < s->nb_streams; ++i) {
-        OutputStream *os = &c->streams[i];
-        if (os->ctx && os->ctx_inited) {
-            av_write_trailer(os->ctx);
-        }
-
-        if (c->remove_at_exit) {
+    if (c->remove_at_exit) {
+        for (i = 0; i < s->nb_streams; ++i) {
+            OutputStream *os = &c->streams[i];
             dashenc_delete_media_segments(s, os, os->nb_segments);
             dashenc_delete_segment_file(s, os->initfile);
+            if (c->hls_playlist && os->segment_type == SEGMENT_TYPE_MP4) {
+                char filename[1024];
+                get_hls_playlist_name(filename, sizeof(filename), c->dirname, i);
+                dashenc_delete_file(s, filename);
+            }
         }
-    }
-
-    if (c->remove_at_exit) {
         dashenc_delete_file(s, s->url);
 
         if (c->hls_playlist && c->master_playlist_created) {
             char filename[1024];
-            for (i = 0; i < s->nb_streams; ++i) {
-                OutputStream *os = &c->streams[i];
-                if (os->segment_type == SEGMENT_TYPE_MP4) {
-                    get_hls_playlist_name(filename, sizeof(filename), c->dirname, i);
-                    dashenc_delete_file(s, filename);
-                }
-            }
             snprintf(filename, sizeof(filename), "%smaster.m3u8", c->dirname);
             dashenc_delete_file(s, filename);
         }
@@ -1816,6 +1858,7 @@ static const AVOption options[] = {
     { "timeout", "set timeout for socket I/O operations", OFFSET(timeout), AV_OPT_TYPE_DURATION, { .i64 = -1 }, -1, INT_MAX, .flags = E },
     { "index_correction", "Enable/Disable segment index correction logic", OFFSET(index_correction), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, E },
     { "format_options","set list of options for the container format (mp4/webm) used for dash", OFFSET(format_options_str), AV_OPT_TYPE_STRING, {.str = NULL},  0, 0, E},
+    { "global_sidx", "Write global SIDX atom. Applicable only for single file, mp4 output, non-streaming mode", OFFSET(global_sidx), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, E },
     { "dash_segment_type", "set dash segment files type", OFFSET(segment_type_option), AV_OPT_TYPE_INT, {.i64 = SEGMENT_TYPE_AUTO }, 0, SEGMENT_TYPE_NB - 1, E, "segment_type"},
     { "auto", "select segment file format based on codec", 0, AV_OPT_TYPE_CONST, {.i64 = SEGMENT_TYPE_AUTO }, 0, UINT_MAX,   E, "segment_type"},
     { "mp4", "make segment file in ISOBMFF format", 0, AV_OPT_TYPE_CONST, {.i64 = SEGMENT_TYPE_MP4 }, 0, UINT_MAX,   E, "segment_type"},
-- 
2.17.2 (Apple Git-113)



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