dashdemux: corrected computation of period's duration

According to ISO/IEC 23009-1:2014(E), chapter 5.3.2.1
"The Period extends until the PeriodStart of the next Period, or until
the end of the Media Presentation in the case of the last Period."

This means that a configured value for optional attribute period duration
should be ignored if the next period contains a start attribute or it is
the last period and the MPD contains a mediaPresentationDuration attribute.

https://bugzilla.gnome.org/show_bug.cgi?id=750797
This commit is contained in:
Florin Apostol 2015-06-15 12:59:55 +01:00 committed by Sebastian Dröge
parent 0a5b6d9344
commit 8336d7a60b
2 changed files with 116 additions and 3 deletions

View file

@ -3391,6 +3391,12 @@ gst_mpd_client_setup_media_presentation (GstMpdClient * client)
period_node = (GstPeriodNode *) list->data;
if (period_node->start != -1) {
/* we have a regular period */
/* start cannot be smaller than previous start */
if (list != g_list_first (client->mpd_node->Periods)
&& start >= period_node->start * GST_MSECOND) {
/* Invalid MPD file: duration would be negative or zero */
goto syntax_error;
}
start = period_node->start * GST_MSECOND;
} else if (duration != GST_CLOCK_TIME_NONE) {
/* start time inferred from previous period, this is still a regular period */
@ -3405,13 +3411,26 @@ gst_mpd_client_setup_media_presentation (GstMpdClient * client)
goto early;
}
if (period_node->duration != -1) {
duration = period_node->duration * GST_MSECOND;
} else if ((next = g_list_next (list)) != NULL) {
/* compute duration.
If there is a start time for the next period, or this is the last period
and mediaPresentationDuration was set, those values will take precedence
over a configured period duration in computing this period's duration
ISO/IEC 23009-1:2014(E), chapter 5.3.2.1
"The Period extends until the PeriodStart of the next Period, or until
the end of the Media Presentation in the case of the last Period."
*/
if ((next = g_list_next (list)) != NULL) {
/* try to infer this period duration from the start time of the next period */
GstPeriodNode *next_period_node = next->data;
if (next_period_node->start != -1) {
if (start >= next_period_node->start * GST_MSECOND) {
/* Invalid MPD file: duration would be negative or zero */
goto syntax_error;
}
duration = next_period_node->start * GST_MSECOND - start;
} else if (period_node->duration != -1) {
duration = period_node->duration * GST_MSECOND;
} else if (client->mpd_node->type == GST_MPD_FILE_TYPE_DYNAMIC) {
/* might be a live file, ignore unspecified duration */
} else {
@ -3420,8 +3439,14 @@ gst_mpd_client_setup_media_presentation (GstMpdClient * client)
}
} else if (client->mpd_node->mediaPresentationDuration != -1) {
/* last Period of the Media Presentation */
if (client->mpd_node->mediaPresentationDuration * GST_MSECOND <= start) {
/* Invalid MPD file: duration would be negative or zero */
goto syntax_error;
}
duration =
client->mpd_node->mediaPresentationDuration * GST_MSECOND - start;
} else if (period_node->duration != -1) {
duration = period_node->duration * GST_MSECOND;
} else if (client->mpd_node->type == GST_MPD_FILE_TYPE_DYNAMIC) {
/* might be a live file, ignore unspecified duration */
} else {

View file

@ -499,6 +499,90 @@ GST_START_TEST (dash_mpdparser_no_default_namespace)
GST_END_TEST;
/*
* Test handling wrong period duration during attempts to
* infer a period duration from the start time of the next period
*/
GST_START_TEST (dash_mpdparser_wrong_period_duration_inferred_from_next_period)
{
const gchar *periodName;
const gchar *xml =
"<?xml version=\"1.0\"?>"
"<MPD xmlns=\"urn:mpeg:dash:schema:mpd:2011\""
" profiles=\"urn:mpeg:dash:profile:isoff-main:2011\""
" availabilityStartTime=\"2015-03-24T0:0:0\""
" mediaPresentationDuration=\"P0Y0M0DT3H3M30S\">"
"<Period id=\"Period0\" duration=\"P0Y0M0DT1H1M0S\"></Period>"
"<Period id=\"Period1\"></Period>"
"<Period id=\"Period2\" start=\"P0Y0M0DT0H0M10S\"></Period></MPD>";
gboolean ret;
GstMpdClient *mpdclient = gst_mpd_client_new ();
ret = gst_mpd_parse (mpdclient, xml, (gint) strlen (xml));
assert_equals_int (ret, TRUE);
/* period_idx should be 0 and we should have no active periods */
assert_equals_uint64 (mpdclient->period_idx, 0);
fail_unless (mpdclient->periods == NULL);
/* process the xml data */
ret = gst_mpd_client_setup_media_presentation (mpdclient);
assert_equals_int (ret, TRUE);
/* Period0 should be present */
fail_unless (mpdclient->periods != NULL);
periodName = gst_mpd_client_get_period_id (mpdclient);
assert_equals_string (periodName, "Period0");
/* Period1 should not be present due to wrong duration */
ret = gst_mpd_client_set_period_index (mpdclient, 1);
assert_equals_int (ret, FALSE);
gst_mpd_client_free (mpdclient);
}
GST_END_TEST;
/*
* Test handling wrong period duration during attempts to
* infer a period duration from the mediaPresentationDuration
*/
GST_START_TEST
(dash_mpdparser_wrong_period_duration_inferred_from_next_mediaPresentationDuration)
{
const gchar *xml =
"<?xml version=\"1.0\"?>"
"<MPD xmlns=\"urn:mpeg:dash:schema:mpd:2011\""
" profiles=\"urn:mpeg:dash:profile:isoff-main:2011\""
" availabilityStartTime=\"2015-03-24T0:0:0\""
" mediaPresentationDuration=\"P0Y0M0DT3H3M30S\">"
"<Period id=\"Period0\" start=\"P0Y0M0DT4H0M0S\"></Period></MPD>";
gboolean ret;
GstMpdClient *mpdclient = gst_mpd_client_new ();
ret = gst_mpd_parse (mpdclient, xml, (gint) strlen (xml));
assert_equals_int (ret, TRUE);
/* period_idx should be 0 and we should have no active periods */
assert_equals_uint64 (mpdclient->period_idx, 0);
fail_unless (mpdclient->periods == NULL);
/* process the xml data
* should fail due to wrong duration in Period0 (start > mediaPresentationDuration)
*/
ret = gst_mpd_client_setup_media_presentation (mpdclient);
assert_equals_int (ret, FALSE);
gst_mpd_client_free (mpdclient);
}
GST_END_TEST;
/*
* create a test suite containing all dash testcases
*/
@ -534,6 +618,10 @@ dash_suite (void)
tcase_add_test (tc_negativeTests, dash_mpdparser_missing_mpd);
tcase_add_test (tc_negativeTests, dash_mpdparser_no_end_tag);
tcase_add_test (tc_negativeTests, dash_mpdparser_no_default_namespace);
tcase_add_test (tc_negativeTests,
dash_mpdparser_wrong_period_duration_inferred_from_next_period);
tcase_add_test (tc_negativeTests,
dash_mpdparser_wrong_period_duration_inferred_from_next_mediaPresentationDuration);
suite_add_tcase (s, tc_simpleMPD);
suite_add_tcase (s, tc_complexMPD);