[FFmpeg-devel] [PATCH 3/3] lavf/webm_dash: some fields should go into Representation

Vignesh Venkatasubramanian vigneshv at google.com
Wed Oct 1 19:13:32 CEST 2014


Width, Height and Sample Rate should be in the AdaptationSet tag
only if all the contained representations have the same width,
height and sampling rate. Otherwise they should go into the
Representation tag. This patch adds this functionality and a fate
test for the same.

Signed-off-by: Vignesh Venkatasubramanian <vigneshv at google.com>
---
 libavformat/webmdashenc.c                         | 116 +++++++++++++++++-----
 tests/fate/vpx.mak                                |   3 +
 tests/ref/fate/webm-dash-manifest-representations |  30 ++++++
 3 files changed, 125 insertions(+), 24 deletions(-)
 create mode 100644 tests/ref/fate/webm-dash-manifest-representations

diff --git a/libavformat/webmdashenc.c b/libavformat/webmdashenc.c
index 849b241..768b5d2 100644
--- a/libavformat/webmdashenc.c
+++ b/libavformat/webmdashenc.c
@@ -133,6 +133,80 @@ static int bitstream_switching(AVFormatContext *s, AdaptationSet *as) {
 }
 
 /*
+ * Writes a Representation within an Adaptation Set. Returns 0 on success and
+ * < 0 on failure.
+ */
+static int write_representation(AVFormatContext *s, AVStream *stream, int id,
+                                int output_width, int output_height,
+                                int output_sample_rate) {
+    AVDictionaryEntry *irange = av_dict_get(stream->metadata, INITIALIZATION_RANGE, NULL, 0);
+    AVDictionaryEntry *cues_start = av_dict_get(stream->metadata, CUES_START, NULL, 0);
+    AVDictionaryEntry *cues_end = av_dict_get(stream->metadata, CUES_END, NULL, 0);
+    AVDictionaryEntry *filename = av_dict_get(stream->metadata, FILENAME, NULL, 0);
+    AVDictionaryEntry *bandwidth = av_dict_get(stream->metadata, BANDWIDTH, NULL, 0);
+    if (!irange || cues_start == NULL || cues_end == NULL || filename == NULL ||
+        !bandwidth) {
+        return -1;
+    }
+    avio_printf(s->pb, "<Representation id=\"%d\"", id);
+    avio_printf(s->pb, " bandwidth=\"%s\"", bandwidth->value);
+    if (stream->codec->codec_type == AVMEDIA_TYPE_VIDEO && output_width)
+        avio_printf(s->pb, " width=\"%d\"", stream->codec->width);
+    if (stream->codec->codec_type == AVMEDIA_TYPE_VIDEO && output_height)
+        avio_printf(s->pb, " height=\"%d\"", stream->codec->height);
+    if (stream->codec->codec_type = AVMEDIA_TYPE_AUDIO && output_sample_rate)
+        avio_printf(s->pb, " audioSamplingRate=\"%d\"", stream->codec->sample_rate);
+    avio_printf(s->pb, ">\n");
+    avio_printf(s->pb, "<BaseURL>%s</BaseURL>\n", filename->value);
+    avio_printf(s->pb, "<SegmentBase\n");
+    avio_printf(s->pb, "  indexRange=\"%s-%s\">\n", cues_start->value, cues_end->value);
+    avio_printf(s->pb, "<Initialization\n");
+    avio_printf(s->pb, "  range=\"0-%s\" />\n", irange->value);
+    avio_printf(s->pb, "</SegmentBase>\n");
+    avio_printf(s->pb, "</Representation>\n");
+    return 0;
+}
+
+/*
+ * Checks if width of all streams are the same. Returns 1 if true, 0 otherwise.
+ */
+static int check_matching_width(AVFormatContext *s, AdaptationSet *as) {
+    int first_width, i;
+    if (as->nb_streams < 2) return 1;
+    first_width = s->streams[as->streams[0]]->codec->width;
+    for (i = 1; i < as->nb_streams; i++)
+        if (first_width != s->streams[as->streams[i]]->codec->width)
+          return 0;
+    return 1;
+}
+
+/*
+ * Checks if height of all streams are the same. Returns 1 if true, 0 otherwise.
+ */
+static int check_matching_height(AVFormatContext *s, AdaptationSet *as) {
+    int first_height, i;
+    if (as->nb_streams < 2) return 1;
+    first_height = s->streams[as->streams[0]]->codec->height;
+    for (i = 1; i < as->nb_streams; i++)
+        if (first_height != s->streams[as->streams[i]]->codec->height)
+          return 0;
+    return 1;
+}
+
+/*
+ * Checks if sample rate of all streams are the same. Returns 1 if true, 0 otherwise.
+ */
+static int check_matching_sample_rate(AVFormatContext *s, AdaptationSet *as) {
+    int first_sample_rate, i;
+    if (as->nb_streams < 2) return 1;
+    first_sample_rate = s->streams[as->streams[0]]->codec->sample_rate;
+    for (i = 1; i < as->nb_streams; i++)
+        if (first_sample_rate != s->streams[as->streams[i]]->codec->sample_rate)
+          return 0;
+    return 1;
+}
+
+/*
  * Writes an Adaptation Set. Returns 0 on success and < 0 on failure.
  */
 static int write_adaptation_set(AVFormatContext *s, int as_index)
@@ -140,10 +214,22 @@ static int write_adaptation_set(AVFormatContext *s, int as_index)
     WebMDashMuxContext *w = s->priv_data;
     AdaptationSet *as = &w->as[as_index];
     AVCodecContext *codec = s->streams[as->streams[0]]->codec;
+    AVDictionaryEntry *lang;
     int i;
     static const char boolean[2][6] = { "false", "true" };
     int subsegmentStartsWithSAP = 1;
-    AVDictionaryEntry *lang;
+
+    // Width, Height and Sample Rate will go in the AdaptationSet tag if they
+    // are the same for all contained Representations. otherwise, they will go
+    // on their respective Representation tag.
+    int width_in_as = 1, height_in_as = 1, sample_rate_in_as = 1;
+    if (codec->codec_type == AVMEDIA_TYPE_VIDEO) {
+      width_in_as = check_matching_width(s, as);
+      height_in_as = check_matching_height(s, as);
+    } else {
+      sample_rate_in_as = check_matching_sample_rate(s, as);
+    }
+
     avio_printf(s->pb, "<AdaptationSet id=\"%s\"", as->id);
     avio_printf(s->pb, " mimeType=\"%s/webm\"",
                 codec->codec_type == AVMEDIA_TYPE_VIDEO ? "video" : "audio");
@@ -152,12 +238,12 @@ static int write_adaptation_set(AVFormatContext *s, int as_index)
     lang = av_dict_get(s->streams[as->streams[0]]->metadata, "language", NULL, 0);
     if (lang) avio_printf(s->pb, " lang=\"%s\"", lang->value);
 
-    if (codec->codec_type == AVMEDIA_TYPE_VIDEO) {
+    if (codec->codec_type == AVMEDIA_TYPE_VIDEO && width_in_as)
         avio_printf(s->pb, " width=\"%d\"", codec->width);
+    if (codec->codec_type == AVMEDIA_TYPE_VIDEO && height_in_as)
         avio_printf(s->pb, " height=\"%d\"", codec->height);
-    } else {
+    if (codec->codec_type == AVMEDIA_TYPE_AUDIO && sample_rate_in_as)
         avio_printf(s->pb, " audioSamplingRate=\"%d\"", codec->sample_rate);
-    }
 
     avio_printf(s->pb, " bitstreamSwitching=\"%s\"",
                 boolean[bitstream_switching(s, as)]);
@@ -173,26 +259,8 @@ static int write_adaptation_set(AVFormatContext *s, int as_index)
     avio_printf(s->pb, ">\n");
 
     for (i = 0; i < as->nb_streams; i++) {
-        AVStream *stream = s->streams[as->streams[i]];
-        AVDictionaryEntry *irange = av_dict_get(stream->metadata, INITIALIZATION_RANGE, NULL, 0);
-        AVDictionaryEntry *cues_start = av_dict_get(stream->metadata, CUES_START, NULL, 0);
-        AVDictionaryEntry *cues_end = av_dict_get(stream->metadata, CUES_END, NULL, 0);
-        AVDictionaryEntry *filename = av_dict_get(stream->metadata, FILENAME, NULL, 0);
-        AVDictionaryEntry *bandwidth = av_dict_get(stream->metadata, BANDWIDTH, NULL, 0);
-        if (!irange || cues_start == NULL || cues_end == NULL || filename == NULL ||
-            !bandwidth) {
-            return -1;
-        }
-        avio_printf(s->pb, "<Representation id=\"%d\"", i);
-        avio_printf(s->pb, " bandwidth=\"%s\"", bandwidth->value);
-        avio_printf(s->pb, ">\n");
-        avio_printf(s->pb, "<BaseURL>%s</BaseURL>\n", filename->value);
-        avio_printf(s->pb, "<SegmentBase\n");
-        avio_printf(s->pb, "  indexRange=\"%s-%s\">\n", cues_start->value, cues_end->value);
-        avio_printf(s->pb, "<Initialization\n");
-        avio_printf(s->pb, "  range=\"0-%s\" />\n", irange->value);
-        avio_printf(s->pb, "</SegmentBase>\n");
-        avio_printf(s->pb, "</Representation>\n");
+        write_representation(s, s->streams[as->streams[i]], i,
+                             !width_in_as, !height_in_as, !sample_rate_in_as);
     }
     avio_printf(s->pb, "</AdaptationSet>\n");
     return 0;
diff --git a/tests/fate/vpx.mak b/tests/fate/vpx.mak
index 0f84ef5..be3e956 100644
--- a/tests/fate/vpx.mak
+++ b/tests/fate/vpx.mak
@@ -37,6 +37,9 @@ fate-webm-dash-manifest-unaligned-video-streams: CMD = run ffmpeg -f webm_dash_m
 FATE_VP8-$(call DEMDEC, WEBM_DASH_MANIFEST, VP8) += fate-webm-dash-manifest-unaligned-audio-streams
 fate-webm-dash-manifest-unaligned-audio-streams: CMD = run ffmpeg -f webm_dash_manifest -i $(TARGET_SAMPLES)/vp8/dash_audio1.webm -f webm_dash_manifest -i $(TARGET_SAMPLES)/vp8/dash_audio3.webm -c copy -map 0 -map 1 -f webm_dash_manifest -adaptation_sets "id=0,streams=0,1" -
 
+FATE_VP8-$(call DEMDEC, WEBM_DASH_MANIFEST, VP8) += fate-webm-dash-manifest-representations
+fate-webm-dash-manifest-representations: CMD = run ffmpeg -f webm_dash_manifest -i $(TARGET_SAMPLES)/vp8/dash_video1.webm -f webm_dash_manifest -i $(TARGET_SAMPLES)/vp8/dash_video4.webm -c copy -map 0 -map 1 -f webm_dash_manifest -adaptation_sets "id=0,streams=0,1" -
+
 FATE_SAMPLES_AVCONV += $(FATE_VP6-yes)
 fate-vp6: $(FATE_VP6-yes)
 
diff --git a/tests/ref/fate/webm-dash-manifest-representations b/tests/ref/fate/webm-dash-manifest-representations
new file mode 100644
index 0000000..8556ece
--- /dev/null
+++ b/tests/ref/fate/webm-dash-manifest-representations
@@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<MPD
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xmlns="urn:mpeg:DASH:schema:MPD:2011"
+  xsi:schemaLocation="urn:mpeg:DASH:schema:MPD:2011"
+  type="static"
+  mediaPresentationDuration="PT32.48S"
+  minBufferTime="PT1S"
+  profiles="urn:webm:dash:profile:webm-on-demand:2012">
+<Period id="0" start="PT0S" duration="PT32.48S" >
+<AdaptationSet id="0" mimeType="video/webm" codecs="vp8" lang="eng" bitstreamSwitching="true" subsegmentAlignment="false" subsegmentStartsWithSAP="1">
+<Representation id="0" bandwidth="302355" width="640" height="360">
+<BaseURL>dash_video1.webm</BaseURL>
+<SegmentBase
+  indexRange="1115974-1116097">
+<Initialization
+  range="0-441" />
+</SegmentBase>
+</Representation>
+<Representation id="1" bandwidth="243938" width="320" height="240">
+<BaseURL>dash_video4.webm</BaseURL>
+<SegmentBase
+  indexRange="871124-871645">
+<Initialization
+  range="0-437" />
+</SegmentBase>
+</Representation>
+</AdaptationSet>
+</Period>
+</MPD>
-- 
2.1.0.rc2.206.gedb03e5



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