const char *gf_isom_subtitle_get_mime(GF_ISOFile *the_file, u32 trackNumber, u32 StreamDescriptionIndex)
{
	GF_TrackBox *trak;
	GF_TextConfigBox *mime;
	GF_MetaDataSampleEntryBox *entry;
	trak = gf_isom_get_track_from_file(the_file, trackNumber);
	if (!trak || !StreamDescriptionIndex) return NULL;

	entry = (GF_MetaDataSampleEntryBox *)gf_list_get(trak->Media->information->sampleTable->SampleDescription->child_boxes, StreamDescriptionIndex-1);
	if (!entry) return NULL;

	mime = (GF_TextConfigBox *) gf_isom_box_find_child(entry->child_boxes, GF_ISOM_BOX_TYPE_MIME);
	if (!mime) return NULL;
	return mime->config;
}
const char *gf_isom_subtitle_get_mime(GF_ISOFile *the_file, u32 trackNumber, u32 StreamDescriptionIndex)
{
	GF_TrackBox *trak;
	GF_TextConfigBox *mime;
	GF_MetaDataSampleEntryBox *entry;
	trak = gf_isom_get_track_from_file(the_file, trackNumber);
	if (!trak || !StreamDescriptionIndex) return NULL;

	entry = (GF_MetaDataSampleEntryBox *)gf_list_get(trak->Media->information->sampleTable->SampleDescription->child_boxes, StreamDescriptionIndex-1);
	if (!entry) return NULL;

	mime = (GF_TextConfigBox *) gf_isom_box_find_child(entry->child_boxes, GF_ISOM_BOX_TYPE_MIME);
	if (!mime) return NULL;
	return mime->config;
}