/* GStreamer * Copyright (C) <1999> Erik Walthinsen * Copyright (C) <2003> David Schleef * * 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. */ #ifdef HAVE_CONFIG_H #include #endif #include #include "gsttextoverlay.h" static GstElementDetails textoverlay_details = { "Text Overlay", "Filter/Editor/Video", "Adds text strings on top of a video buffer", "David Schleef " }; enum { ARG_0, ARG_TEXT, ARG_VALIGN, ARG_HALIGN, ARG_X0, ARG_Y0, ARG_FONT_DESC }; static GstStaticPadTemplate textoverlay_src_template_factory = GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS, GST_STATIC_CAPS ("video/x-raw-yuv, " "format = (fourcc) I420, " "width = (int) [ 1, MAX ], " "height = (int) [ 1, MAX ]") ); static GstStaticPadTemplate video_sink_template_factory = GST_STATIC_PAD_TEMPLATE ("video_sink", GST_PAD_SINK, GST_PAD_ALWAYS, GST_STATIC_CAPS ("video/x-raw-yuv, " "format = (fourcc) I420, " "width = (int) [ 1, MAX ], " "height = (int) [ 1, MAX ]") ); static GstStaticPadTemplate text_sink_template_factory = GST_STATIC_PAD_TEMPLATE ("text_sink", GST_PAD_SINK, GST_PAD_ALWAYS, GST_STATIC_CAPS ("text/plain") ); static void gst_textoverlay_base_init (gpointer g_class); static void gst_textoverlay_class_init (GstTextOverlayClass * klass); static void gst_textoverlay_init (GstTextOverlay * overlay); static void gst_textoverlay_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec); static void gst_textoverlay_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec); static GstElementStateReturn gst_textoverlay_change_state (GstElement * element); static void gst_textoverlay_finalize (GObject * object); static GstElementClass *parent_class = NULL; /*static guint gst_textoverlay_signals[LAST_SIGNAL] = { 0 }; */ GType gst_textoverlay_get_type (void) { static GType textoverlay_type = 0; if (!textoverlay_type) { static const GTypeInfo textoverlay_info = { sizeof (GstTextOverlayClass), gst_textoverlay_base_init, NULL, (GClassInitFunc) gst_textoverlay_class_init, NULL, NULL, sizeof (GstTextOverlay), 0, (GInstanceInitFunc) gst_textoverlay_init, }; textoverlay_type = g_type_register_static (GST_TYPE_ELEMENT, "GstTextOverlay", &textoverlay_info, 0); } return textoverlay_type; } static void gst_textoverlay_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 (&textoverlay_src_template_factory)); gst_element_class_add_pad_template (element_class, gst_static_pad_template_get (&video_sink_template_factory)); gst_element_class_add_pad_template (element_class, gst_static_pad_template_get (&text_sink_template_factory)); gst_element_class_set_details (element_class, &textoverlay_details); } static void gst_textoverlay_class_init (GstTextOverlayClass * klass) { GObjectClass *gobject_class; GstElementClass *gstelement_class; gobject_class = (GObjectClass *) klass; gstelement_class = (GstElementClass *) klass; parent_class = g_type_class_peek_parent (klass); gobject_class->finalize = gst_textoverlay_finalize; gobject_class->set_property = gst_textoverlay_set_property; gobject_class->get_property = gst_textoverlay_get_property; gstelement_class->change_state = gst_textoverlay_change_state; g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_TEXT, g_param_spec_string ("text", "text", "Text to be display.", "", G_PARAM_WRITABLE)); g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_VALIGN, g_param_spec_string ("valign", "vertical alignment", "Vertical alignment of the text. " "Can be either 'baseline', 'bottom', or 'top'", "baseline", G_PARAM_WRITABLE)); g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_HALIGN, g_param_spec_string ("halign", "horizontal alignment", "Horizontal alignment of the text. " "Can be either 'left', 'right', or 'center'", "center", G_PARAM_WRITABLE)); g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_X0, g_param_spec_int ("x0", "X position", "Initial X position." " Horizontal aligment takes this point" " as reference.", G_MININT, G_MAXINT, 0, G_PARAM_WRITABLE)); g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_Y0, g_param_spec_int ("y0", "Y position", "Initial Y position." " Vertical aligment takes this point" " as reference.", G_MININT, G_MAXINT, 0, G_PARAM_WRITABLE)); g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_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)); } #if 0 static void resize_bitmap (GstTextOverlay * overlay, int width, int height) { FT_Bitmap *bitmap = &overlay->bitmap; int pitch = (width | 3) + 1; int size = pitch * height; /* no need to keep reallocating; just keep the maximum size so far */ if (size <= overlay->bitmap_buffer_size) { bitmap->rows = height; bitmap->width = width; bitmap->pitch = pitch; memset (bitmap->buffer, 0, overlay->bitmap_buffer_size); return; } if (!bitmap->buffer) { /* initialize */ bitmap->pixel_mode = ft_pixel_mode_grays; bitmap->num_grays = 256; } if (bitmap->buffer) bitmap->buffer = g_realloc (bitmap->buffer, size); else bitmap->buffer = g_malloc (size); bitmap->rows = height; bitmap->width = width; bitmap->pitch = pitch; memset (bitmap->buffer, 0, size); overlay->bitmap_buffer_size = size; } #endif static void gst_textoverlay_render_text (GstTextOverlay * overlay, gchar * text, int textlen) { cairo_text_extents_t extents; char *string; double x, y; string = g_strndup (text, textlen); if (overlay->text_fill_image) g_free (overlay->text_fill_image); overlay->text_fill_image = g_malloc (4 * overlay->width * overlay->text_height); cairo_set_target_image (overlay->cr, overlay->text_fill_image, CAIRO_FORMAT_ARGB32, overlay->width, overlay->text_height, overlay->width * 4); cairo_save (overlay->cr); cairo_rectangle (overlay->cr, 0, 0, overlay->width, overlay->text_height); cairo_set_rgb_color (overlay->cr, 0, 0, 0); cairo_set_alpha (overlay->cr, 1.0); cairo_set_operator (overlay->cr, CAIRO_OPERATOR_SRC); cairo_fill (overlay->cr); cairo_restore (overlay->cr); cairo_save (overlay->cr); cairo_text_extents (overlay->cr, string, &extents); cairo_set_rgb_color (overlay->cr, 1, 1, 1); cairo_set_alpha (overlay->cr, 1.0); switch (overlay->halign) { case GST_TEXT_OVERLAY_HALIGN_LEFT: x = overlay->x0; break; case GST_TEXT_OVERLAY_HALIGN_CENTER: x = overlay->x0 - extents.width / 2; break; case GST_TEXT_OVERLAY_HALIGN_RIGHT: x = overlay->x0 - extents.width; break; default: x = 0; } y = overlay->text_height - 2; cairo_move_to (overlay->cr, x, y); cairo_show_text (overlay->cr, string); cairo_restore (overlay->cr); if (overlay->text_outline_image) g_free (overlay->text_outline_image); overlay->text_outline_image = g_malloc (4 * overlay->width * overlay->text_height); cairo_set_target_image (overlay->cr, overlay->text_outline_image, CAIRO_FORMAT_ARGB32, overlay->width, overlay->text_height, overlay->width * 4); cairo_save (overlay->cr); cairo_rectangle (overlay->cr, 0, 0, overlay->width, overlay->text_height); cairo_set_rgb_color (overlay->cr, 0, 0, 0); cairo_set_alpha (overlay->cr, 1.0); cairo_set_operator (overlay->cr, CAIRO_OPERATOR_SRC); cairo_fill (overlay->cr); cairo_restore (overlay->cr); cairo_save (overlay->cr); cairo_move_to (overlay->cr, x, y); cairo_set_rgb_color (overlay->cr, 1, 1, 1); cairo_set_alpha (overlay->cr, 1.0); cairo_set_line_width (overlay->cr, 1.0); cairo_text_path (overlay->cr, string); cairo_stroke (overlay->cr); cairo_restore (overlay->cr); g_free (string); } /* static GstPadLinkReturn */ /* gst_textoverlay_text_sinkconnect (GstPad *pad, GstCaps *caps) */ /* { */ /* return GST_PAD_LINK_DONE; */ /* } */ static GstPadLinkReturn gst_textoverlay_video_sinkconnect (GstPad * pad, const GstCaps * caps) { GstTextOverlay *overlay; GstStructure *structure; overlay = GST_TEXTOVERLAY (gst_pad_get_parent (pad)); structure = gst_caps_get_structure (caps, 0); overlay->width = overlay->height = 0; gst_structure_get_int (structure, "width", &overlay->width); gst_structure_get_int (structure, "height", &overlay->height); return gst_pad_try_set_caps (overlay->srcpad, caps); } static void gst_text_overlay_blit_1 (GstTextOverlay * overlay, guchar * dest, guchar * text_image, int val) { int i; int j; int x, a, y; int y0 = 0; y = val; for (i = 0; i < overlay->text_height; i++) { for (j = 0; j < overlay->width; j++) { x = dest[(i + y0) * overlay->width + j]; a = text_image[4 * (i * overlay->width + j) + 1]; dest[(i + y0) * overlay->width + j] = (y * a + x * (255 - a)) / 255; } } } static void gst_text_overlay_blit_sub2x2 (GstTextOverlay * overlay, guchar * dest, guchar * text_image, int val) { int i; int j; int x, a, y; int y0 = 0; y = val; for (i = 0; i < overlay->text_height; i += 2) { for (j = 0; j < overlay->width; j += 2) { x = dest[(i / 2 + y0) * (overlay->width / 2) + j / 2]; a = (text_image[4 * (i * overlay->width + j) + 1] + text_image[4 * (i * overlay->width + j + 1) + 1] + text_image[4 * ((i + 1) * overlay->width + j) + 1] + text_image[4 * ((i + 1) * overlay->width + j + 1) + 1] + 2) / 4; dest[(i / 2 + y0) * (overlay->width / 2) + j / 2] = (y * a + x * (255 - a)) / 255; } } } static void gst_textoverlay_video_chain (GstPad * pad, GstData * _data) { GstBuffer *buf = GST_BUFFER (_data); GstTextOverlay *overlay; guchar *pixbuf; gint y; g_return_if_fail (pad != NULL); g_return_if_fail (GST_IS_PAD (pad)); g_return_if_fail (buf != NULL); overlay = GST_TEXTOVERLAY (gst_pad_get_parent (pad)); g_return_if_fail (overlay != NULL); g_return_if_fail (GST_IS_TEXTOVERLAY (overlay)); if (!GST_IS_BUFFER (_data)) return; pixbuf = GST_BUFFER_DATA (buf); y = overlay->y0; switch (overlay->valign) { case GST_TEXT_OVERLAY_VALIGN_BOTTOM: y -= overlay->text_height; break; case GST_TEXT_OVERLAY_VALIGN_BASELINE: #define BASELINE 2 y -= (overlay->text_height - BASELINE); break; case GST_TEXT_OVERLAY_VALIGN_TOP: break; } gst_text_overlay_blit_1 (overlay, pixbuf + y * overlay->width, overlay->text_outline_image, 0); gst_text_overlay_blit_sub2x2 (overlay, pixbuf + (overlay->height * overlay->width) + (y / 2) * overlay->width / 2, overlay->text_outline_image, 128); gst_text_overlay_blit_sub2x2 (overlay, pixbuf + (overlay->height * overlay->width) + (overlay->height * overlay->width) / 4 + (y / 2) * overlay->width / 2, overlay->text_outline_image, 128); gst_text_overlay_blit_1 (overlay, pixbuf + y * overlay->width, overlay->text_fill_image, 255); gst_text_overlay_blit_sub2x2 (overlay, pixbuf + (overlay->height * overlay->width) + (y / 2) * overlay->width / 2, overlay->text_fill_image, 128); gst_text_overlay_blit_sub2x2 (overlay, pixbuf + (overlay->height * overlay->width) + (overlay->height * overlay->width) / 4 + (y / 2) * overlay->width / 2, overlay->text_fill_image, 128); gst_pad_push (overlay->srcpad, GST_DATA (buf)); } #define PAST_END(buffer, time) \ (GST_BUFFER_TIMESTAMP (buffer) != GST_CLOCK_TIME_NONE && \ GST_BUFFER_DURATION (buffer) != GST_CLOCK_TIME_NONE && \ GST_BUFFER_TIMESTAMP (buffer) + GST_BUFFER_DURATION (buffer) \ < (time)) static void gst_textoverlay_loop (GstElement * element) { GstTextOverlay *overlay; GstBuffer *video_frame; guint64 now; g_return_if_fail (element != NULL); g_return_if_fail (GST_IS_TEXTOVERLAY (element)); overlay = GST_TEXTOVERLAY (element); do { GST_DEBUG ("Attempting to pull next video frame"); video_frame = GST_BUFFER (gst_pad_pull (overlay->video_sinkpad)); if (GST_IS_EVENT (video_frame)) { GstEvent *event = GST_EVENT (video_frame); GstEventType type = GST_EVENT_TYPE (event); gst_pad_event_default (overlay->video_sinkpad, event); GST_DEBUG ("Received event of type %d", type); if (type == GST_EVENT_EOS || type == GST_EVENT_INTERRUPT) return; video_frame = NULL; } } while (!video_frame); now = GST_BUFFER_TIMESTAMP (video_frame); GST_DEBUG ("Got video frame, time=%" GST_TIME_FORMAT, GST_TIME_ARGS (now)); /* * This state machine has a bug that can't be resolved easily. * (Needs a more complicated state machine.) Basically, if the * text that came from a buffer from the sink pad is being * displayed, and the default text is changed by set_parameter, * we'll incorrectly display the default text. * * Otherwise, this is a pretty decent state machine that handles * buffer timestamps and durations correctly. (I think) */ while ((!overlay->current_buffer || PAST_END (overlay->current_buffer, now)) && overlay->next_buffer == NULL) { GST_DEBUG ("attempting to pull a buffer"); /* read all text buffers until we get one "in the future" */ if (!GST_PAD_IS_USABLE (overlay->text_sinkpad)) { break; } do { overlay->next_buffer = GST_BUFFER (gst_pad_pull (overlay->text_sinkpad)); if (GST_IS_EVENT (overlay->next_buffer)) { GstEvent *event = GST_EVENT (overlay->next_buffer); GstEventType type = GST_EVENT_TYPE (event); gst_pad_event_default (overlay->text_sinkpad, event); if (type == GST_EVENT_EOS || type == GST_EVENT_INTERRUPT) return; overlay->next_buffer = NULL; } } while (!overlay->next_buffer); if (PAST_END (overlay->next_buffer, now)) { GST_DEBUG ("Received buffer is past end (%" GST_TIME_FORMAT " + %" GST_TIME_FORMAT " < %" GST_TIME_FORMAT ")", GST_TIME_ARGS (GST_BUFFER_TIMESTAMP (overlay->next_buffer)), GST_TIME_ARGS (GST_BUFFER_DURATION (overlay->next_buffer)), GST_TIME_ARGS (now)); gst_buffer_unref (overlay->next_buffer); overlay->next_buffer = NULL; } else { GST_DEBUG ("Received new text buffer of time %" GST_TIME_FORMAT "and duration %" GST_TIME_FORMAT, GST_TIME_ARGS (GST_BUFFER_TIMESTAMP (overlay->next_buffer)), GST_TIME_ARGS (GST_BUFFER_DURATION (overlay->next_buffer))); } } if (overlay->next_buffer && (GST_BUFFER_TIMESTAMP (overlay->next_buffer) <= now || GST_BUFFER_TIMESTAMP (overlay->next_buffer) == GST_CLOCK_TIME_NONE)) { GST_DEBUG ("using new buffer"); if (overlay->current_buffer) { gst_buffer_unref (overlay->current_buffer); } overlay->current_buffer = overlay->next_buffer; overlay->next_buffer = NULL; GST_DEBUG ("rendering '%*s'", GST_BUFFER_SIZE (overlay->current_buffer), GST_BUFFER_DATA (overlay->current_buffer)); gst_textoverlay_render_text (overlay, GST_BUFFER_DATA (overlay->current_buffer), GST_BUFFER_SIZE (overlay->current_buffer)); overlay->need_render = FALSE; } if (overlay->current_buffer && PAST_END (overlay->current_buffer, now)) { GST_DEBUG ("dropping old buffer"); gst_buffer_unref (overlay->current_buffer); overlay->current_buffer = NULL; overlay->need_render = TRUE; } if (overlay->need_render) { GST_DEBUG ("rendering '%s'", overlay->default_text); gst_textoverlay_render_text (overlay, overlay->default_text, strlen (overlay->default_text)); overlay->need_render = FALSE; } gst_textoverlay_video_chain (overlay->srcpad, GST_DATA (video_frame)); } static void gst_textoverlay_font_init (GstTextOverlay * overlay) { cairo_font_extents_t font_extents; cairo_select_font (overlay->cr, overlay->font, overlay->slant, overlay->weight); cairo_scale_font (overlay->cr, overlay->scale); cairo_current_font_extents (overlay->cr, &font_extents); overlay->text_height = font_extents.height; if (overlay->text_height & 1) overlay->text_height++; overlay->need_render = TRUE; } static GstElementStateReturn gst_textoverlay_change_state (GstElement * element) { GstTextOverlay *overlay; overlay = GST_TEXTOVERLAY (element); switch (GST_STATE_TRANSITION (element)) { case GST_STATE_PAUSED_TO_PLAYING: break; case GST_STATE_PLAYING_TO_PAUSED: break; case GST_STATE_PAUSED_TO_READY: break; } parent_class->change_state (element); return GST_STATE_SUCCESS; } static void gst_textoverlay_finalize (GObject * object) { GstTextOverlay *overlay = GST_TEXTOVERLAY (object); if (overlay->cr) { cairo_destroy (overlay->cr); } G_OBJECT_CLASS (parent_class)->finalize (object); } static void gst_textoverlay_init (GstTextOverlay * overlay) { /* video sink */ overlay->video_sinkpad = gst_pad_new_from_template (gst_static_pad_template_get (&video_sink_template_factory), "video_sink"); gst_pad_set_link_function (overlay->video_sinkpad, gst_textoverlay_video_sinkconnect); gst_element_add_pad (GST_ELEMENT (overlay), overlay->video_sinkpad); /* text sink */ overlay->text_sinkpad = gst_pad_new_from_template (gst_static_pad_template_get (&text_sink_template_factory), "text_sink"); gst_element_add_pad (GST_ELEMENT (overlay), overlay->text_sinkpad); /* (video) source */ overlay->srcpad = gst_pad_new_from_template (gst_static_pad_template_get (&textoverlay_src_template_factory), "src"); gst_element_add_pad (GST_ELEMENT (overlay), overlay->srcpad); overlay->cr = cairo_create (); overlay->halign = GST_TEXT_OVERLAY_HALIGN_CENTER; overlay->valign = GST_TEXT_OVERLAY_VALIGN_BASELINE; overlay->x0 = overlay->y0 = 25; overlay->default_text = g_strdup (""); overlay->need_render = TRUE; overlay->font = g_strdup ("sans"); overlay->slant = CAIRO_FONT_SLANT_NORMAL; overlay->weight = CAIRO_FONT_WEIGHT_NORMAL; overlay->scale = 20; gst_textoverlay_font_init (overlay); gst_element_set_loop_function (GST_ELEMENT (overlay), gst_textoverlay_loop); } static void gst_textoverlay_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec) { GstTextOverlay *overlay; /* it's not null if we got it, but it might not be ours */ g_return_if_fail (GST_IS_TEXTOVERLAY (object)); overlay = GST_TEXTOVERLAY (object); switch (prop_id) { case ARG_TEXT: if (overlay->default_text) { g_free (overlay->default_text); } overlay->default_text = g_strdup (g_value_get_string (value)); overlay->need_render = TRUE; break; case ARG_VALIGN: if (strcasecmp (g_value_get_string (value), "baseline") == 0) overlay->valign = GST_TEXT_OVERLAY_VALIGN_BASELINE; else if (strcasecmp (g_value_get_string (value), "bottom") == 0) overlay->valign = GST_TEXT_OVERLAY_VALIGN_BOTTOM; else if (strcasecmp (g_value_get_string (value), "top") == 0) overlay->valign = GST_TEXT_OVERLAY_VALIGN_TOP; else g_warning ("Invalid 'valign' property value: %s", g_value_get_string (value)); overlay->need_render = TRUE; break; case ARG_HALIGN: if (strcasecmp (g_value_get_string (value), "left") == 0) overlay->halign = GST_TEXT_OVERLAY_HALIGN_LEFT; else if (strcasecmp (g_value_get_string (value), "right") == 0) overlay->halign = GST_TEXT_OVERLAY_HALIGN_RIGHT; else if (strcasecmp (g_value_get_string (value), "center") == 0) overlay->halign = GST_TEXT_OVERLAY_HALIGN_CENTER; else g_warning ("Invalid 'halign' property value: %s", g_value_get_string (value)); overlay->need_render = TRUE; break; case ARG_X0: overlay->x0 = g_value_get_int (value); break; case ARG_Y0: overlay->y0 = g_value_get_int (value); break; case ARG_FONT_DESC: if (overlay->font) g_free (overlay->font); overlay->font = g_strdup (g_value_get_string (value)); gst_textoverlay_font_init (overlay); break; default: break; } } static void gst_textoverlay_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec) { GstTextOverlay *overlay; /* it's not null if we got it, but it might not be ours */ g_return_if_fail (GST_IS_TEXTOVERLAY (object)); overlay = GST_TEXTOVERLAY (object); switch (prop_id) { default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } }