/* GStreamer * Copyright (C) <1999> Erik Walthinsen * Copyright (C) <2003> David Schleef * Copyright (C) <2009> Young-Ho Cha * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ /** * SECTION:element-textrender * @see_also: #GstTextOverlay * * This plugin renders text received on the text sink pad to a video * buffer (retaining the alpha channel), so it can later be overlayed * on top of video streams using other elements. * * The text can contain newline characters. (FIXME: What about text * wrapping? It does not make sense in this context) * * * Example launch lines * |[ * gst-launch -v filesrc location=subtitles.srt ! subparse ! textrender ! xvimagesink * ]| * */ #ifdef HAVE_CONFIG_H #include #endif #include #include #include "gsttextrender.h" #include #if G_BYTE_ORDER == G_LITTLE_ENDIAN # define CAIRO_ARGB_A 3 # define CAIRO_ARGB_R 2 # define CAIRO_ARGB_G 1 # define CAIRO_ARGB_B 0 #else # define CAIRO_ARGB_A 0 # define CAIRO_ARGB_R 1 # define CAIRO_ARGB_G 2 # define CAIRO_ARGB_B 3 #endif GST_DEBUG_CATEGORY_EXTERN (pango_debug); #define GST_CAT_DEFAULT pango_debug #define MINIMUM_OUTLINE_OFFSET 1.0 #define DEFAULT_PROP_VALIGNMENT GST_TEXT_RENDER_VALIGN_BASELINE #define DEFAULT_PROP_HALIGNMENT GST_TEXT_RENDER_HALIGN_CENTER #define DEFAULT_PROP_LINE_ALIGNMENT GST_TEXT_RENDER_LINE_ALIGN_CENTER #define DEFAULT_PROP_XPAD 25 #define DEFAULT_PROP_YPAD 25 #define DEFAULT_RENDER_WIDTH 720 #define DEFAULT_RENDER_HEIGHT 576 enum { PROP_0, PROP_HALIGNMENT, PROP_VALIGNMENT, PROP_LINE_ALIGNMENT, PROP_XPAD, PROP_YPAD, PROP_FONT_DESC }; static GstStaticPadTemplate src_template_factory = GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS, GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("AYUV") ";" GST_VIDEO_CAPS_ARGB) ); static GstStaticPadTemplate sink_template_factory = GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS, GST_STATIC_CAPS ("text/x-pango-markup; text/plain") ); #define GST_TYPE_TEXT_RENDER_VALIGN (gst_text_render_valign_get_type()) static GType gst_text_render_valign_get_type (void) { static GType text_render_valign_type = 0; static const GEnumValue text_render_valign[] = { {GST_TEXT_RENDER_VALIGN_BASELINE, "baseline", "baseline"}, {GST_TEXT_RENDER_VALIGN_BOTTOM, "bottom", "bottom"}, {GST_TEXT_RENDER_VALIGN_TOP, "top", "top"}, {0, NULL, NULL}, }; if (!text_render_valign_type) { text_render_valign_type = g_enum_register_static ("GstTextRenderVAlign", text_render_valign); } return text_render_valign_type; } #define GST_TYPE_TEXT_RENDER_HALIGN (gst_text_render_halign_get_type()) static GType gst_text_render_halign_get_type (void) { static GType text_render_halign_type = 0; static const GEnumValue text_render_halign[] = { {GST_TEXT_RENDER_HALIGN_LEFT, "left", "left"}, {GST_TEXT_RENDER_HALIGN_CENTER, "center", "center"}, {GST_TEXT_RENDER_HALIGN_RIGHT, "right", "right"}, {0, NULL, NULL}, }; if (!text_render_halign_type) { text_render_halign_type = g_enum_register_static ("GstTextRenderHAlign", text_render_halign); } return text_render_halign_type; } #define GST_TYPE_TEXT_RENDER_LINE_ALIGN (gst_text_render_line_align_get_type()) static GType gst_text_render_line_align_get_type (void) { static GType text_render_line_align_type = 0; static const GEnumValue text_render_line_align[] = { {GST_TEXT_RENDER_LINE_ALIGN_LEFT, "left", "left"}, {GST_TEXT_RENDER_LINE_ALIGN_CENTER, "center", "center"}, {GST_TEXT_RENDER_LINE_ALIGN_RIGHT, "right", "right"}, {0, NULL, NULL} }; if (!text_render_line_align_type) { text_render_line_align_type = g_enum_register_static ("GstTextRenderLineAlign", text_render_line_align); } return text_render_line_align_type; } static void gst_text_render_adjust_values_with_fontdesc (GstTextRender * render, PangoFontDescription * desc); GST_BOILERPLATE (GstTextRender, gst_text_render, GstElement, GST_TYPE_ELEMENT); static void gst_text_render_finalize (GObject * object); static void gst_text_render_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec); static void gst_text_render_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec); static void gst_text_render_base_init (gpointer g_class) { GstElementClass *element_class = GST_ELEMENT_CLASS (g_class); gst_element_class_add_pad_template (element_class, gst_static_pad_template_get (&src_template_factory)); gst_element_class_add_pad_template (element_class, gst_static_pad_template_get (&sink_template_factory)); gst_element_class_set_details_simple (element_class, "Text renderer", "Filter/Editor/Video", "Renders a text string to an image bitmap", "David Schleef , " "GStreamer maintainers "); } static void gst_text_render_class_init (GstTextRenderClass * klass) { GObjectClass *gobject_class; PangoFontMap *fontmap; gobject_class = (GObjectClass *) klass; parent_class = g_type_class_peek_parent (klass); gobject_class->finalize = gst_text_render_finalize; gobject_class->set_property = gst_text_render_set_property; gobject_class->get_property = gst_text_render_get_property; fontmap = pango_cairo_font_map_get_default (); klass->pango_context = pango_cairo_font_map_create_context (PANGO_CAIRO_FONT_MAP (fontmap)); g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_FONT_DESC, g_param_spec_string ("font-desc", "font description", "Pango font description of font " "to be used for rendering. " "See documentation of " "pango_font_description_from_string" " for syntax.", "", G_PARAM_WRITABLE | G_PARAM_STATIC_STRINGS)); g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_VALIGNMENT, g_param_spec_enum ("valignment", "vertical alignment", "Vertical alignment of the text", GST_TYPE_TEXT_RENDER_VALIGN, DEFAULT_PROP_VALIGNMENT, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)); g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_HALIGNMENT, g_param_spec_enum ("halignment", "horizontal alignment", "Horizontal alignment of the text", GST_TYPE_TEXT_RENDER_HALIGN, DEFAULT_PROP_HALIGNMENT, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)); g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_XPAD, g_param_spec_int ("xpad", "horizontal paddding", "Horizontal paddding when using left/right alignment", 0, G_MAXINT, DEFAULT_PROP_XPAD, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)); g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_YPAD, g_param_spec_int ("ypad", "vertical padding", "Vertical padding when using top/bottom alignment", 0, G_MAXINT, DEFAULT_PROP_YPAD, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)); g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_LINE_ALIGNMENT, g_param_spec_enum ("line-alignment", "line alignment", "Alignment of text lines relative to each other.", GST_TYPE_TEXT_RENDER_LINE_ALIGN, DEFAULT_PROP_LINE_ALIGNMENT, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)); } static void gst_text_render_adjust_values_with_fontdesc (GstTextRender * render, PangoFontDescription * desc) { gint font_size = pango_font_description_get_size (desc) / PANGO_SCALE; render->shadow_offset = (double) (font_size) / 13.0; render->outline_offset = (double) (font_size) / 15.0; if (render->outline_offset < MINIMUM_OUTLINE_OFFSET) render->outline_offset = MINIMUM_OUTLINE_OFFSET; } static void gst_text_render_render_pangocairo (GstTextRender * render) { cairo_t *cr; cairo_surface_t *surface; cairo_t *cr_shadow; cairo_surface_t *surface_shadow; PangoRectangle ink_rect, logical_rect; gint width, height; pango_layout_get_pixel_extents (render->layout, &ink_rect, &logical_rect); width = logical_rect.width + render->shadow_offset; height = logical_rect.height + logical_rect.y + render->shadow_offset; surface_shadow = cairo_image_surface_create (CAIRO_FORMAT_A8, width, height); cr_shadow = cairo_create (surface_shadow); /* clear shadow surface */ cairo_set_operator (cr_shadow, CAIRO_OPERATOR_CLEAR); cairo_paint (cr_shadow); cairo_set_operator (cr_shadow, CAIRO_OPERATOR_OVER); /* draw shadow text */ cairo_save (cr_shadow); cairo_set_source_rgba (cr_shadow, 0.0, 0.0, 0.0, 0.5); cairo_translate (cr_shadow, render->shadow_offset, render->shadow_offset); pango_cairo_show_layout (cr_shadow, render->layout); cairo_restore (cr_shadow); /* draw outline text */ cairo_save (cr_shadow); cairo_set_source_rgb (cr_shadow, 0.0, 0.0, 0.0); cairo_set_line_width (cr_shadow, render->outline_offset); pango_cairo_layout_path (cr_shadow, render->layout); cairo_stroke (cr_shadow); cairo_restore (cr_shadow); cairo_destroy (cr_shadow); render->text_image = g_realloc (render->text_image, 4 * width * height); surface = cairo_image_surface_create_for_data (render->text_image, CAIRO_FORMAT_ARGB32, width, height, width * 4); cr = cairo_create (surface); cairo_set_operator (cr, CAIRO_OPERATOR_CLEAR); cairo_paint (cr); cairo_set_operator (cr, CAIRO_OPERATOR_OVER); /* set default color */ cairo_set_source_rgb (cr, 1.0, 1.0, 1.0); cairo_save (cr); /* draw text */ pango_cairo_show_layout (cr, render->layout); cairo_restore (cr); /* composite shadow with offset */ cairo_set_operator (cr, CAIRO_OPERATOR_DEST_OVER); cairo_set_source_surface (cr, surface_shadow, 0.0, 0.0); cairo_paint (cr); cairo_destroy (cr); cairo_surface_destroy (surface_shadow); cairo_surface_destroy (surface); render->image_width = width; render->image_height = height; } static void gst_text_render_check_argb (GstTextRender * render) { GstCaps *peer_caps; peer_caps = gst_pad_get_allowed_caps (render->srcpad); if (G_LIKELY (peer_caps)) { guint i = 0, n = 0; n = gst_caps_get_size (peer_caps); GST_DEBUG_OBJECT (render, "peer allowed caps (%u structure(s)) are %" GST_PTR_FORMAT, n, peer_caps); /* Check if AYUV or ARGB is first */ for (i = 0; i < n; i++) { GstStructure *s = gst_caps_get_structure (peer_caps, i); if (gst_structure_has_name (s, "video/x-raw-rgb") && gst_structure_has_field (s, "alpha_mask")) { render->use_ARGB = TRUE; break; } else if (gst_structure_has_name (s, "video/x-raw-yuv")) { guint fourcc; if (gst_structure_get_fourcc (s, "format", &fourcc) && fourcc == GST_MAKE_FOURCC ('A', 'Y', 'U', 'V')) { render->use_ARGB = FALSE; break; } } } gst_caps_unref (peer_caps); } } static gboolean gst_text_render_setcaps (GstPad * pad, GstCaps * caps) { GstTextRender *render = GST_TEXT_RENDER (gst_pad_get_parent (pad)); GstStructure *structure; gboolean ret = FALSE; gint width = 0, height = 0; structure = gst_caps_get_structure (caps, 0); gst_structure_get_int (structure, "width", &width); gst_structure_get_int (structure, "height", &height); GST_DEBUG ("Got caps %" GST_PTR_FORMAT, caps); if (width >= render->image_width && height >= render->image_height) { render->width = width; render->height = height; ret = TRUE; } gst_text_render_check_argb (render); gst_object_unref (render); return ret; } static void gst_text_render_fixate_caps (GstPad * pad, GstCaps * caps) { GstTextRender *render = GST_TEXT_RENDER (gst_pad_get_parent (pad)); GstStructure *s = gst_caps_get_structure (caps, 0); GST_DEBUG ("Fixating caps %" GST_PTR_FORMAT, caps); gst_structure_fixate_field_nearest_int (s, "width", render->image_width); gst_structure_fixate_field_nearest_int (s, "height", render->image_height); GST_DEBUG ("Fixated to %" GST_PTR_FORMAT, caps); gst_object_unref (render); } static void gst_text_renderer_image_to_ayuv (GstTextRender * render, guchar * pixbuf, int xpos, int ypos, int stride) { int y; /* text bitmap coordinates */ guchar *p, *bitp; guchar a, r, g, b; int width, height; width = render->image_width; height = render->image_height; bitp = render->text_image; for (y = 0; y < height; y++) { int n; p = pixbuf + (ypos + y) * stride + xpos * 4; for (n = 0; n < width; n++) { b = bitp[CAIRO_ARGB_B]; g = bitp[CAIRO_ARGB_G]; r = bitp[CAIRO_ARGB_R]; a = bitp[CAIRO_ARGB_A]; bitp += 4; *p++ = a; *p++ = CLAMP ((int) (((19595 * r) >> 16) + ((38470 * g) >> 16) + ((7471 * b) >> 16)), 0, 255); *p++ = CLAMP ((int) (-((11059 * r) >> 16) - ((21709 * g) >> 16) + ((32768 * b) >> 16) + 128), 0, 255); *p++ = CLAMP ((int) (((32768 * r) >> 16) - ((27439 * g) >> 16) - ((5329 * b) >> 16) + 128), 0, 255); } } } static void gst_text_renderer_image_to_argb (GstTextRender * render, guchar * pixbuf, int xpos, int ypos, int stride) { int i, j; guchar *p, *bitp; int width, height; width = render->image_width; height = render->image_height; bitp = render->text_image; for (i = 0; i < height; i++) { p = pixbuf + (ypos + i) * stride + xpos * 4; for (j = 0; j < width; j++) { p[0] = bitp[CAIRO_ARGB_A]; p[1] = bitp[CAIRO_ARGB_R]; p[2] = bitp[CAIRO_ARGB_G]; p[3] = bitp[CAIRO_ARGB_B]; bitp += 4; p += 4; } } } static GstFlowReturn gst_text_render_chain (GstPad * pad, GstBuffer * inbuf) { GstTextRender *render; GstFlowReturn ret; GstBuffer *outbuf; GstCaps *caps = NULL; guint8 *data = GST_BUFFER_DATA (inbuf); guint size = GST_BUFFER_SIZE (inbuf); gint n; gint xpos, ypos; render = GST_TEXT_RENDER (gst_pad_get_parent (pad)); /* somehow pango barfs over "\0" buffers... */ while (size > 0 && (data[size - 1] == '\r' || data[size - 1] == '\n' || data[size - 1] == '\0')) { size--; } /* render text */ GST_DEBUG ("rendering '%*s'", size, data); pango_layout_set_markup (render->layout, (gchar *) data, size); gst_text_render_render_pangocairo (render); gst_text_render_check_argb (render); if (!render->use_ARGB) { caps = gst_video_format_new_caps (GST_VIDEO_FORMAT_AYUV, render->width, render->height, 1, 1, 1, 1); } else { caps = gst_video_format_new_caps (GST_VIDEO_FORMAT_ARGB, render->width, render->height, 1, 1, 1, 1); } if (!gst_pad_set_caps (render->srcpad, caps)) { gst_caps_unref (caps); GST_ELEMENT_ERROR (render, CORE, NEGOTIATION, (NULL), (NULL)); ret = GST_FLOW_ERROR; goto done; } GST_DEBUG ("Allocating buffer WxH = %dx%d", render->width, render->height); ret = gst_pad_alloc_buffer_and_set_caps (render->srcpad, GST_BUFFER_OFFSET_NONE, render->width * render->height * 4, caps, &outbuf); if (ret != GST_FLOW_OK) goto done; gst_buffer_copy_metadata (outbuf, inbuf, GST_BUFFER_COPY_TIMESTAMPS); data = GST_BUFFER_DATA (outbuf); if (render->use_ARGB) { memset (data, 0, render->width * render->height * 4); } else { for (n = 0; n < render->width * render->height; n++) { data[n * 4] = data[n * 4 + 1] = 0; data[n * 4 + 2] = data[n * 4 + 3] = 128; } } switch (render->halign) { case GST_TEXT_RENDER_HALIGN_LEFT: xpos = render->xpad; break; case GST_TEXT_RENDER_HALIGN_CENTER: xpos = (render->width - render->image_width) / 2; break; case GST_TEXT_RENDER_HALIGN_RIGHT: xpos = render->width - render->image_width - render->xpad; break; default: xpos = 0; } switch (render->valign) { case GST_TEXT_RENDER_VALIGN_BOTTOM: ypos = render->height - render->image_height - render->ypad; break; case GST_TEXT_RENDER_VALIGN_BASELINE: ypos = render->height - (render->image_height + render->ypad); break; case GST_TEXT_RENDER_VALIGN_TOP: ypos = render->ypad; break; default: ypos = render->ypad; break; } if (render->text_image) { if (render->use_ARGB) { gst_text_renderer_image_to_argb (render, data, xpos, ypos, render->width * 4); } else { gst_text_renderer_image_to_ayuv (render, data, xpos, ypos, render->width * 4); } } ret = gst_pad_push (render->srcpad, outbuf); done: if (caps) gst_caps_unref (caps); gst_buffer_unref (inbuf); gst_object_unref (render); return ret; } static void gst_text_render_finalize (GObject * object) { GstTextRender *render = GST_TEXT_RENDER (object); g_free (render->text_image); if (render->layout) g_object_unref (render->layout); G_OBJECT_CLASS (parent_class)->finalize (object); } static void gst_text_render_init (GstTextRender * render, GstTextRenderClass * klass) { GstPadTemplate *template; /* sink */ template = gst_static_pad_template_get (&sink_template_factory); render->sinkpad = gst_pad_new_from_template (template, "sink"); gst_object_unref (template); gst_pad_set_chain_function (render->sinkpad, GST_DEBUG_FUNCPTR (gst_text_render_chain)); gst_element_add_pad (GST_ELEMENT (render), render->sinkpad); /* source */ template = gst_static_pad_template_get (&src_template_factory); render->srcpad = gst_pad_new_from_template (template, "src"); gst_object_unref (template); gst_pad_set_fixatecaps_function (render->srcpad, GST_DEBUG_FUNCPTR (gst_text_render_fixate_caps)); gst_pad_set_setcaps_function (render->srcpad, GST_DEBUG_FUNCPTR (gst_text_render_setcaps)); gst_element_add_pad (GST_ELEMENT (render), render->srcpad); render->line_align = DEFAULT_PROP_LINE_ALIGNMENT; render->layout = pango_layout_new (GST_TEXT_RENDER_GET_CLASS (render)->pango_context); pango_layout_set_alignment (render->layout, (PangoAlignment) render->line_align); render->halign = DEFAULT_PROP_HALIGNMENT; render->valign = DEFAULT_PROP_VALIGNMENT; render->xpad = DEFAULT_PROP_XPAD; render->ypad = DEFAULT_PROP_YPAD; render->width = DEFAULT_RENDER_WIDTH; render->height = DEFAULT_RENDER_HEIGHT; render->use_ARGB = FALSE; } static void gst_text_render_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec) { GstTextRender *render = GST_TEXT_RENDER (object); switch (prop_id) { case PROP_VALIGNMENT: render->valign = g_value_get_enum (value); break; case PROP_HALIGNMENT: render->halign = g_value_get_enum (value); break; case PROP_LINE_ALIGNMENT: render->line_align = g_value_get_enum (value); pango_layout_set_alignment (render->layout, (PangoAlignment) render->line_align); break; case PROP_XPAD: render->xpad = g_value_get_int (value); break; case PROP_YPAD: render->ypad = g_value_get_int (value); break; case PROP_FONT_DESC: { PangoFontDescription *desc; desc = pango_font_description_from_string (g_value_get_string (value)); if (desc) { GST_LOG ("font description set: %s", g_value_get_string (value)); GST_OBJECT_LOCK (render); pango_layout_set_font_description (render->layout, desc); gst_text_render_adjust_values_with_fontdesc (render, desc); pango_font_description_free (desc); gst_text_render_render_pangocairo (render); GST_OBJECT_UNLOCK (render); } else { GST_WARNING ("font description parse failed: %s", g_value_get_string (value)); } break; } default: break; } } static void gst_text_render_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec) { GstTextRender *render = GST_TEXT_RENDER (object); switch (prop_id) { case PROP_VALIGNMENT: g_value_set_enum (value, render->valign); break; case PROP_HALIGNMENT: g_value_set_enum (value, render->halign); break; case PROP_LINE_ALIGNMENT: g_value_set_enum (value, render->line_align); break; case PROP_XPAD: g_value_set_int (value, render->xpad); break; case PROP_YPAD: g_value_set_int (value, render->ypad); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } }