textoverlay Adds text strings on top of a video buffer @GST_TEXT_OVERLAY_VALIGN_BASELINE: @GST_TEXT_OVERLAY_VALIGN_BOTTOM: @GST_TEXT_OVERLAY_VALIGN_TOP: @GST_TEXT_OVERLAY_HALIGN_LEFT: @GST_TEXT_OVERLAY_HALIGN_CENTER: @GST_TEXT_OVERLAY_HALIGN_RIGHT: @GST_TEXT_OVERLAY_WRAP_MODE_NONE: @GST_TEXT_OVERLAY_WRAP_MODE_WORD: @GST_TEXT_OVERLAY_WRAP_MODE_CHAR: @GST_TEXT_OVERLAY_WRAP_MODE_WORD_CHAR: