GF_Err gf_isom_new_text_description(GF_ISOFile *movie, u32 trackNumber, GF_TextSampleDescriptor *desc, const char *URLname, const char *URNname, u32 *outDescriptionIndex)
{
	GF_TrackBox *trak;
	GF_Err e;
	u32 dataRefIndex, i;
	GF_Tx3gSampleEntryBox *txt;

	e = CanAccessMovie(movie, GF_ISOM_OPEN_WRITE);
	if (e) return e;

	trak = gf_isom_get_track_from_file(movie, trackNumber);
	if (!trak || !trak->Media || !desc || !desc->font_count) return GF_BAD_PARAM;

	switch (trak->Media->handler->handlerType) {
	case GF_ISOM_MEDIA_TEXT:
	case GF_ISOM_MEDIA_SUBT:
		break;
	default:
		return GF_BAD_PARAM;
	}

	//get or create the data ref
	e = Media_FindDataRef(trak->Media->information->dataInformation->dref, (char *)URLname, (char *)URNname, &dataRefIndex);
	if (e) return e;
	if (!dataRefIndex) {
		e = Media_CreateDataRef(movie, trak->Media->information->dataInformation->dref, (char *)URLname, (char *)URNname, &dataRefIndex);
		if (e) return e;
	}
	if (!movie->keep_utc)
		trak->Media->mediaHeader->modificationTime = gf_isom_get_mp4time();

	txt = (GF_Tx3gSampleEntryBox *) gf_isom_box_new(GF_ISOM_BOX_TYPE_TX3G);
	if (!txt) return GF_OUT_OF_MEM;
	txt->dataReferenceIndex = dataRefIndex;
	gf_list_add(trak->Media->information->sampleTable->SampleDescription->child_boxes, txt);
	if (outDescriptionIndex) *outDescriptionIndex = gf_list_count(trak->Media->information->sampleTable->SampleDescription->child_boxes);

	txt->back_color = desc->back_color;
	txt->default_box = desc->default_pos;
	txt->default_style = desc->default_style;
	txt->displayFlags = desc->displayFlags;
	txt->vertical_justification = desc->vert_justif;
	txt->horizontal_justification = desc->horiz_justif;
	txt->font_table = (GF_FontTableBox *)gf_isom_box_new_parent(&txt->child_boxes, GF_ISOM_BOX_TYPE_FTAB);
	if (!txt->font_table) return GF_OUT_OF_MEM;
	txt->font_table->entry_count = desc->font_count;

	txt->font_table->fonts = (GF_FontRecord *) gf_malloc(sizeof(GF_FontRecord) * desc->font_count);
	if (!txt->font_table->fonts) return GF_OUT_OF_MEM;
	for (i=0; i<desc->font_count; i++) {
		txt->font_table->fonts[i].fontID = desc->fonts[i].fontID;
		if (desc->fonts[i].fontName) txt->font_table->fonts[i].fontName = gf_strdup(desc->fonts[i].fontName);
	}
	return e;
}
GF_Err gf_isom_new_text_description(GF_ISOFile *movie, u32 trackNumber, GF_TextSampleDescriptor *desc, const char *URLname, const char *URNname, u32 *outDescriptionIndex)
{
	GF_TrackBox *trak;
	GF_Err e;
	u32 dataRefIndex, i;
	GF_Tx3gSampleEntryBox *txt;

	e = CanAccessMovie(movie, GF_ISOM_OPEN_WRITE);
	if (e) return e;

	trak = gf_isom_get_track_from_file(movie, trackNumber);
	if (!trak || !trak->Media || !desc || !desc->font_count) return GF_BAD_PARAM;

	switch (trak->Media->handler->handlerType) {
	case GF_ISOM_MEDIA_TEXT:
	case GF_ISOM_MEDIA_SUBT:
		break;
	default:
		return GF_BAD_PARAM;
	}

	 
	e = Media_FindDataRef(trak->Media->information->dataInformation->dref, (char *)URLname, (char *)URNname, &dataRefIndex);
	if (e) return e;
	if (!dataRefIndex) {
		e = Media_CreateDataRef(movie, trak->Media->information->dataInformation->dref, (char *)URLname, (char *)URNname, &dataRefIndex);
		if (e) return e;
	}
	if (!movie->keep_utc)
		trak->Media->mediaHeader->modificationTime = gf_isom_get_mp4time();

	txt = (GF_Tx3gSampleEntryBox *) gf_isom_box_new(GF_ISOM_BOX_TYPE_TX3G);
	if (!txt) return GF_OUT_OF_MEM;
	txt->dataReferenceIndex = dataRefIndex;
	gf_list_add(trak->Media->information->sampleTable->SampleDescription->child_boxes, txt);
	if (outDescriptionIndex) *outDescriptionIndex = gf_list_count(trak->Media->information->sampleTable->SampleDescription->child_boxes);

	txt->back_color = desc->back_color;
	txt->default_box = desc->default_pos;
	txt->default_style = desc->default_style;
	txt->displayFlags = desc->displayFlags;
	txt->vertical_justification = desc->vert_justif;
	txt->horizontal_justification = desc->horiz_justif;
	txt->font_table = (GF_FontTableBox *)gf_isom_box_new_parent(&txt->child_boxes, GF_ISOM_BOX_TYPE_FTAB);
	if (!txt->font_table) return GF_OUT_OF_MEM;
	txt->font_table->entry_count = desc->font_count;

	txt->font_table->fonts = (GF_FontRecord *) gf_malloc(sizeof(GF_FontRecord) * desc->font_count);
	if (!txt->font_table->fonts) return GF_OUT_OF_MEM;
	for (i=0; i<desc->font_count; i++) {
		txt->font_table->fonts[i].fontID = desc->fonts[i].fontID;
		if (desc->fonts[i].fontName) txt->font_table->fonts[i].fontName = gf_strdup(desc->fonts[i].fontName);
	}
	return e;
}