/* GStreamer TTML subtitle parser * Copyright (C) <2015> British Broadcasting Corporation * Authors: * Chris Bass <dash@rd.bbc.co.uk> * Peter Taylour <dash@rd.bbc.co.uk> * * 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., 51 Franklin St, Fifth Floor, * Boston, MA 02110-1301, USA. */ /* * Parses subtitle files encoded using the EBU-TT-D profile of TTML, as defined * in https://tech.ebu.ch/files/live/sites/tech/files/shared/tech/tech3380.pdf * and http://www.w3.org/TR/ttaf1-dfxp/, respectively. */ #include <glib.h> #include <string.h> #include <stdlib.h> #include <stdio.h> #include <math.h> #include <libxml/xmlmemory.h> #include <libxml/parser.h> #include "ttmlparse.h" #include "subtitle.h" #include "subtitlemeta.h" #define DEFAULT_CELLRES_X 32 #define DEFAULT_CELLRES_Y 15 #define MAX_FONT_FAMILY_NAME_LENGTH 128 #define NSECONDS_IN_DAY 24 * 3600 * GST_SECOND #define TTML_CHAR_NULL 0x00 #define TTML_CHAR_SPACE 0x20 #define TTML_CHAR_TAB 0x09 #define TTML_CHAR_LF 0x0A #define TTML_CHAR_CR 0x0D GST_DEBUG_CATEGORY_EXTERN (ttmlparse_debug); #define GST_CAT_DEFAULT ttmlparse_debug static gchar *ttml_get_xml_property (const xmlNode * node, const char *name); static gpointer ttml_copy_tree_element (gconstpointer src, gpointer data); typedef struct _TtmlStyleSet TtmlStyleSet; typedef struct _TtmlElement TtmlElement; typedef struct _TtmlScene TtmlScene; typedef enum { TTML_ELEMENT_TYPE_STYLE, TTML_ELEMENT_TYPE_REGION, TTML_ELEMENT_TYPE_BODY, TTML_ELEMENT_TYPE_DIV, TTML_ELEMENT_TYPE_P, TTML_ELEMENT_TYPE_SPAN, TTML_ELEMENT_TYPE_ANON_SPAN, TTML_ELEMENT_TYPE_BR } TtmlElementType; typedef enum { TTML_WHITESPACE_MODE_NONE, TTML_WHITESPACE_MODE_DEFAULT, TTML_WHITESPACE_MODE_PRESERVE, } TtmlWhitespaceMode; struct _TtmlElement { TtmlElementType type; gchar *id; TtmlWhitespaceMode whitespace_mode; gchar **styles; gchar *region; GstClockTime begin; GstClockTime end; TtmlStyleSet *style_set; gchar *text; }; /* Represents a static scene consisting of one or more trees of elements that * should be visible over a specific period of time. */ struct _TtmlScene { GstClockTime begin; GstClockTime end; GList *trees; GstBuffer *buf; }; struct _TtmlStyleSet { GHashTable *table; }; static TtmlStyleSet * ttml_style_set_new (void) { TtmlStyleSet *ret = g_new0 (TtmlStyleSet, 1); ret->table = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free); return ret; } static void ttml_style_set_delete (TtmlStyleSet * style_set) { if (style_set) { g_hash_table_unref (style_set->table); g_free (style_set); } } /* If attribute with name @attr_name already exists in @style_set, its value * will be replaced by @attr_value. */ static gboolean ttml_style_set_add_attr (TtmlStyleSet * style_set, const gchar * attr_name, const gchar * attr_value) { return g_hash_table_insert (style_set->table, g_strdup (attr_name), g_strdup (attr_value)); } static gboolean ttml_style_set_contains_attr (TtmlStyleSet * style_set, const gchar * attr_name) { return g_hash_table_contains (style_set->table, attr_name); } static const gchar * ttml_style_set_get_attr (TtmlStyleSet * style_set, const gchar * attr_name) { return g_hash_table_lookup (style_set->table, attr_name); } static guint8 ttml_hex_pair_to_byte (const gchar * hex_pair) { gint hi_digit, lo_digit; hi_digit = g_ascii_xdigit_value (*hex_pair); lo_digit = g_ascii_xdigit_value (*(hex_pair + 1)); return (hi_digit << 4) + lo_digit; } /* Color strings in EBU-TT-D can have the form "#RRBBGG" or "#RRBBGGAA". */ static GstSubtitleColor ttml_parse_colorstring (const gchar * color) { guint length; const gchar *c = NULL; GstSubtitleColor ret = { 0, 0, 0, 0 }; if (!color) return ret; length = strlen (color); if (((length == 7) || (length == 9)) && *color == '#') { c = color + 1; ret.r = ttml_hex_pair_to_byte (c); ret.g = ttml_hex_pair_to_byte (c + 2); ret.b = ttml_hex_pair_to_byte (c + 4); if (length == 7) ret.a = G_MAXUINT8; else ret.a = ttml_hex_pair_to_byte (c + 6); GST_CAT_LOG (ttmlparse_debug, "Returning color - r:%u b:%u g:%u a:%u", ret.r, ret.b, ret.g, ret.a); } else { GST_CAT_ERROR (ttmlparse_debug, "Invalid color string: %s", color); } return ret; } static void ttml_style_set_print (TtmlStyleSet * style_set) { GHashTableIter iter; gpointer attr_name, attr_value; if (!style_set) { GST_CAT_LOG (ttmlparse_debug, "\t\t[NULL]"); return; } g_hash_table_iter_init (&iter, style_set->table); while (g_hash_table_iter_next (&iter, &attr_name, &attr_value)) { GST_CAT_LOG (ttmlparse_debug, "\t\t%s: %s", (const gchar *) attr_name, (const gchar *) attr_value); } } static TtmlStyleSet * ttml_parse_style_set (const xmlNode * node) { TtmlStyleSet *s; gchar *value = NULL; xmlAttrPtr attr; value = ttml_get_xml_property (node, "id"); if (!value) { GST_CAT_ERROR (ttmlparse_debug, "styles must have an ID."); return NULL; } g_free (value); s = ttml_style_set_new (); for (attr = node->properties; attr != NULL; attr = attr->next) { if (attr->ns && ((g_strcmp0 ((const gchar *) attr->ns->prefix, "tts") == 0) || (g_strcmp0 ((const gchar *) attr->ns->prefix, "itts") == 0) || (g_strcmp0 ((const gchar *) attr->ns->prefix, "ebutts") == 0))) { ttml_style_set_add_attr (s, (const gchar *) attr->name, (const gchar *) attr->children->content); } } return s; } static void ttml_delete_element (TtmlElement * element) { g_free ((gpointer) element->id); if (element->styles) g_strfreev (element->styles); g_free ((gpointer) element->region); ttml_style_set_delete (element->style_set); g_free ((gpointer) element->text); g_free (element); } static gchar * ttml_get_xml_property (const xmlNode * node, const char *name) { xmlChar *xml_string = NULL; gchar *gst_string = NULL; g_return_val_if_fail (strlen (name) < 128, NULL); xml_string = xmlGetProp (node, (xmlChar *) name); if (!xml_string) return NULL; gst_string = g_strdup ((gchar *) xml_string); xmlFree (xml_string); return gst_string; } /* EBU-TT-D timecodes have format hours:minutes:seconds[.fraction] */ static GstClockTime ttml_parse_timecode (const gchar * timestring) { gchar **strings; guint64 hours = 0, minutes = 0, seconds = 0, milliseconds = 0; GstClockTime time = GST_CLOCK_TIME_NONE; GST_CAT_LOG (ttmlparse_debug, "time string: %s", timestring); strings = g_strsplit (timestring, ":", 3); if (g_strv_length (strings) != 3U) { GST_CAT_ERROR (ttmlparse_debug, "badly formatted time string: %s", timestring); return time; } hours = g_ascii_strtoull (strings[0], NULL, 10U); minutes = g_ascii_strtoull (strings[1], NULL, 10U); if (g_strstr_len (strings[2], -1, ".")) { guint n_digits; gchar **substrings = g_strsplit (strings[2], ".", 2); seconds = g_ascii_strtoull (substrings[0], NULL, 10U); n_digits = strlen (substrings[1]); milliseconds = g_ascii_strtoull (substrings[1], NULL, 10U); milliseconds = (guint64) (milliseconds * pow (10.0, (3 - (double) n_digits))); g_strfreev (substrings); } else { seconds = g_ascii_strtoull (strings[2], NULL, 10U); } if (minutes > 59 || seconds > 60) { GST_CAT_ERROR (ttmlparse_debug, "invalid time string " "(minutes or seconds out-of-bounds): %s\n", timestring); } g_strfreev (strings); GST_CAT_LOG (ttmlparse_debug, "hours: %" G_GUINT64_FORMAT " minutes: %" G_GUINT64_FORMAT " seconds: %" G_GUINT64_FORMAT " milliseconds: %" G_GUINT64_FORMAT "", hours, minutes, seconds, milliseconds); time = hours * GST_SECOND * 3600 + minutes * GST_SECOND * 60 + seconds * GST_SECOND + milliseconds * GST_MSECOND; return time; } static TtmlElement * ttml_parse_element (const xmlNode * node) { TtmlElement *element; TtmlElementType type; gchar *value; GST_CAT_DEBUG (ttmlparse_debug, "Element name: %s", (const char *) node->name); if ((g_strcmp0 ((const char *) node->name, "style") == 0)) { type = TTML_ELEMENT_TYPE_STYLE; } else if ((g_strcmp0 ((const char *) node->name, "region") == 0)) { type = TTML_ELEMENT_TYPE_REGION; } else if ((g_strcmp0 ((const char *) node->name, "body") == 0)) { type = TTML_ELEMENT_TYPE_BODY; } else if ((g_strcmp0 ((const char *) node->name, "div") == 0)) { type = TTML_ELEMENT_TYPE_DIV; } else if ((g_strcmp0 ((const char *) node->name, "p") == 0)) { type = TTML_ELEMENT_TYPE_P; } else if ((g_strcmp0 ((const char *) node->name, "span") == 0)) { type = TTML_ELEMENT_TYPE_SPAN; } else if ((g_strcmp0 ((const char *) node->name, "text") == 0)) { type = TTML_ELEMENT_TYPE_ANON_SPAN; } else if ((g_strcmp0 ((const char *) node->name, "br") == 0)) { type = TTML_ELEMENT_TYPE_BR; } else { return NULL; } element = g_new0 (TtmlElement, 1); element->type = type; if ((value = ttml_get_xml_property (node, "id"))) { element->id = g_strdup (value); g_free (value); } if ((value = ttml_get_xml_property (node, "style"))) { element->styles = g_strsplit (value, " ", 0); GST_CAT_DEBUG (ttmlparse_debug, "%u style(s) referenced in element.", g_strv_length (element->styles)); g_free (value); } if (element->type == TTML_ELEMENT_TYPE_STYLE || element->type == TTML_ELEMENT_TYPE_REGION) { TtmlStyleSet *ss; ss = ttml_parse_style_set (node); if (ss) element->style_set = ss; else GST_CAT_WARNING (ttmlparse_debug, "Style or Region contains no styling attributes."); } if ((value = ttml_get_xml_property (node, "region"))) { element->region = g_strdup (value); g_free (value); } if ((value = ttml_get_xml_property (node, "begin"))) { element->begin = ttml_parse_timecode (value); g_free (value); } else { element->begin = GST_CLOCK_TIME_NONE; } if ((value = ttml_get_xml_property (node, "end"))) { element->end = ttml_parse_timecode (value); g_free (value); } else { element->end = GST_CLOCK_TIME_NONE; } if (node->content) { GST_CAT_LOG (ttmlparse_debug, "Node content: %s", node->content); element->text = g_strdup ((const gchar *) node->content); } if (element->type == TTML_ELEMENT_TYPE_BR) element->text = g_strdup ("\n"); if ((value = ttml_get_xml_property (node, "space"))) { if (g_strcmp0 (value, "preserve") == 0) element->whitespace_mode = TTML_WHITESPACE_MODE_PRESERVE; else if (g_strcmp0 (value, "default") == 0) element->whitespace_mode = TTML_WHITESPACE_MODE_DEFAULT; g_free (value); } return element; } static GNode * ttml_parse_body (const xmlNode * node) { GNode *ret; TtmlElement *element; GST_CAT_LOG (ttmlparse_debug, "parsing node %s", node->name); element = ttml_parse_element (node); if (element) ret = g_node_new (element); else return NULL; for (node = node->children; node != NULL; node = node->next) { GNode *descendants = NULL; if ((descendants = ttml_parse_body (node))) g_node_append (ret, descendants); } return ret; } /* Update the fields of a GstSubtitleStyleSet, @style_set, according to the * values defined in a TtmlStyleSet, @tss, and a given cell resolution. */ static void ttml_update_style_set (GstSubtitleStyleSet * style_set, TtmlStyleSet * tss, guint cellres_x, guint cellres_y) { const gchar *attr; if ((attr = ttml_style_set_get_attr (tss, "textDirection"))) { if (g_strcmp0 (attr, "rtl") == 0) style_set->text_direction = GST_SUBTITLE_TEXT_DIRECTION_RTL; else style_set->text_direction = GST_SUBTITLE_TEXT_DIRECTION_LTR; } if ((attr = ttml_style_set_get_attr (tss, "fontFamily"))) { if (strlen (attr) <= MAX_FONT_FAMILY_NAME_LENGTH) { g_free (style_set->font_family); style_set->font_family = g_strdup (attr); } else { GST_CAT_WARNING (ttmlparse_debug, "Ignoring font family name as it's overly long."); } } if ((attr = ttml_style_set_get_attr (tss, "fontSize"))) { style_set->font_size = g_ascii_strtod (attr, NULL) / 100.0; } style_set->font_size *= (1.0 / cellres_y); if ((attr = ttml_style_set_get_attr (tss, "lineHeight"))) { if (g_strcmp0 (attr, "normal") == 0) style_set->line_height = -1; else style_set->line_height = g_ascii_strtod (attr, NULL) / 100.0; } if ((attr = ttml_style_set_get_attr (tss, "textAlign"))) { if (g_strcmp0 (attr, "left") == 0) style_set->text_align = GST_SUBTITLE_TEXT_ALIGN_LEFT; else if (g_strcmp0 (attr, "center") == 0) style_set->text_align = GST_SUBTITLE_TEXT_ALIGN_CENTER; else if (g_strcmp0 (attr, "right") == 0) style_set->text_align = GST_SUBTITLE_TEXT_ALIGN_RIGHT; else if (g_strcmp0 (attr, "end") == 0) style_set->text_align = GST_SUBTITLE_TEXT_ALIGN_END; else style_set->text_align = GST_SUBTITLE_TEXT_ALIGN_START; } if ((attr = ttml_style_set_get_attr (tss, "color"))) { style_set->color = ttml_parse_colorstring (attr); } if ((attr = ttml_style_set_get_attr (tss, "backgroundColor"))) { style_set->background_color = ttml_parse_colorstring (attr); } if ((attr = ttml_style_set_get_attr (tss, "fontStyle"))) { if (g_strcmp0 (attr, "italic") == 0) style_set->font_style = GST_SUBTITLE_FONT_STYLE_ITALIC; else style_set->font_style = GST_SUBTITLE_FONT_STYLE_NORMAL; } if ((attr = ttml_style_set_get_attr (tss, "fontWeight"))) { if (g_strcmp0 (attr, "bold") == 0) style_set->font_weight = GST_SUBTITLE_FONT_WEIGHT_BOLD; else style_set->font_weight = GST_SUBTITLE_FONT_WEIGHT_NORMAL; } if ((attr = ttml_style_set_get_attr (tss, "textDecoration"))) { if (g_strcmp0 (attr, "underline") == 0) style_set->text_decoration = GST_SUBTITLE_TEXT_DECORATION_UNDERLINE; else style_set->text_decoration = GST_SUBTITLE_TEXT_DECORATION_NONE; } if ((attr = ttml_style_set_get_attr (tss, "unicodeBidi"))) { if (g_strcmp0 (attr, "embed") == 0) style_set->unicode_bidi = GST_SUBTITLE_UNICODE_BIDI_EMBED; else if (g_strcmp0 (attr, "bidiOverride") == 0) style_set->unicode_bidi = GST_SUBTITLE_UNICODE_BIDI_OVERRIDE; else style_set->unicode_bidi = GST_SUBTITLE_UNICODE_BIDI_NORMAL; } if ((attr = ttml_style_set_get_attr (tss, "wrapOption"))) { if (g_strcmp0 (attr, "noWrap") == 0) style_set->wrap_option = GST_SUBTITLE_WRAPPING_OFF; else style_set->wrap_option = GST_SUBTITLE_WRAPPING_ON; } if ((attr = ttml_style_set_get_attr (tss, "multiRowAlign"))) { if (g_strcmp0 (attr, "start") == 0) style_set->multi_row_align = GST_SUBTITLE_MULTI_ROW_ALIGN_START; else if (g_strcmp0 (attr, "center") == 0) style_set->multi_row_align = GST_SUBTITLE_MULTI_ROW_ALIGN_CENTER; else if (g_strcmp0 (attr, "end") == 0) style_set->multi_row_align = GST_SUBTITLE_MULTI_ROW_ALIGN_END; else style_set->multi_row_align = GST_SUBTITLE_MULTI_ROW_ALIGN_AUTO; } if ((attr = ttml_style_set_get_attr (tss, "linePadding"))) { style_set->line_padding = g_ascii_strtod (attr, NULL); style_set->line_padding *= (1.0 / cellres_x); } if ((attr = ttml_style_set_get_attr (tss, "origin"))) { gchar *c; style_set->origin_x = g_ascii_strtod (attr, &c) / 100.0; while (!g_ascii_isdigit (*c) && *c != '+' && *c != '-') ++c; style_set->origin_y = g_ascii_strtod (c, NULL) / 100.0; } if ((attr = ttml_style_set_get_attr (tss, "extent"))) { gchar *c; style_set->extent_w = g_ascii_strtod (attr, &c) / 100.0; if ((style_set->origin_x + style_set->extent_w) > 1.0) { style_set->extent_w = 1.0 - style_set->origin_x; } while (!g_ascii_isdigit (*c) && *c != '+' && *c != '-') ++c; style_set->extent_h = g_ascii_strtod (c, NULL) / 100.0; if ((style_set->origin_y + style_set->extent_h) > 1.0) { style_set->extent_h = 1.0 - style_set->origin_y; } } if ((attr = ttml_style_set_get_attr (tss, "displayAlign"))) { if (g_strcmp0 (attr, "center") == 0) style_set->display_align = GST_SUBTITLE_DISPLAY_ALIGN_CENTER; else if (g_strcmp0 (attr, "after") == 0) style_set->display_align = GST_SUBTITLE_DISPLAY_ALIGN_AFTER; else style_set->display_align = GST_SUBTITLE_DISPLAY_ALIGN_BEFORE; } if ((attr = ttml_style_set_get_attr (tss, "padding"))) { gchar **decimals; guint n_decimals; guint i; decimals = g_strsplit (attr, "%", 0); n_decimals = g_strv_length (decimals) - 1; for (i = 0; i < n_decimals; ++i) g_strstrip (decimals[i]); switch (n_decimals) { case 1: style_set->padding_start = style_set->padding_end = style_set->padding_before = style_set->padding_after = g_ascii_strtod (decimals[0], NULL) / 100.0; break; case 2: style_set->padding_before = style_set->padding_after = g_ascii_strtod (decimals[0], NULL) / 100.0; style_set->padding_start = style_set->padding_end = g_ascii_strtod (decimals[1], NULL) / 100.0; break; case 3: style_set->padding_before = g_ascii_strtod (decimals[0], NULL) / 100.0; style_set->padding_start = style_set->padding_end = g_ascii_strtod (decimals[1], NULL) / 100.0; style_set->padding_after = g_ascii_strtod (decimals[2], NULL) / 100.0; break; case 4: style_set->padding_before = g_ascii_strtod (decimals[0], NULL) / 100.0; style_set->padding_end = g_ascii_strtod (decimals[1], NULL) / 100.0; style_set->padding_after = g_ascii_strtod (decimals[2], NULL) / 100.0; style_set->padding_start = g_ascii_strtod (decimals[3], NULL) / 100.0; break; } g_strfreev (decimals); /* Padding values in TTML files are relative to the region width & height; * make them relative to the overall display width & height like all other * dimensions. */ style_set->padding_before *= style_set->extent_h; style_set->padding_after *= style_set->extent_h; style_set->padding_end *= style_set->extent_w; style_set->padding_start *= style_set->extent_w; } if ((attr = ttml_style_set_get_attr (tss, "writingMode"))) { if (g_str_has_prefix (attr, "rl")) style_set->writing_mode = GST_SUBTITLE_WRITING_MODE_RLTB; else if ((g_strcmp0 (attr, "tbrl") == 0) || (g_strcmp0 (attr, "tb") == 0)) style_set->writing_mode = GST_SUBTITLE_WRITING_MODE_TBRL; else if (g_strcmp0 (attr, "tblr") == 0) style_set->writing_mode = GST_SUBTITLE_WRITING_MODE_TBLR; else style_set->writing_mode = GST_SUBTITLE_WRITING_MODE_LRTB; } if ((attr = ttml_style_set_get_attr (tss, "showBackground"))) { if (g_strcmp0 (attr, "whenActive") == 0) style_set->show_background = GST_SUBTITLE_BACKGROUND_MODE_WHEN_ACTIVE; else style_set->show_background = GST_SUBTITLE_BACKGROUND_MODE_ALWAYS; } if ((attr = ttml_style_set_get_attr (tss, "overflow"))) { if (g_strcmp0 (attr, "visible") == 0) style_set->overflow = GST_SUBTITLE_OVERFLOW_MODE_VISIBLE; else style_set->overflow = GST_SUBTITLE_OVERFLOW_MODE_HIDDEN; } if ((attr = ttml_style_set_get_attr (tss, "fillLineGap"))) { if (g_strcmp0 (attr, "true") == 0) style_set->fill_line_gap = TRUE; } } static TtmlStyleSet * ttml_style_set_copy (TtmlStyleSet * style_set) { GHashTableIter iter; gpointer attr_name, attr_value; TtmlStyleSet *ret = ttml_style_set_new (); g_hash_table_iter_init (&iter, style_set->table); while (g_hash_table_iter_next (&iter, &attr_name, &attr_value)) { ttml_style_set_add_attr (ret, (const gchar *) attr_name, (const gchar *) attr_value); } return ret; } /* set2 overrides set1. Unlike style inheritance, merging will result in all * values from set1 being merged into set2. */ static TtmlStyleSet * ttml_style_set_merge (TtmlStyleSet * set1, TtmlStyleSet * set2) { TtmlStyleSet *ret = NULL; if (set1) { ret = ttml_style_set_copy (set1); if (set2) { GHashTableIter iter; gpointer attr_name, attr_value; g_hash_table_iter_init (&iter, set2->table); while (g_hash_table_iter_next (&iter, &attr_name, &attr_value)) { ttml_style_set_add_attr (ret, (const gchar *) attr_name, (const gchar *) attr_value); } } } else if (set2) { ret = ttml_style_set_copy (set2); } return ret; } static gchar * ttml_get_relative_font_size (const gchar * parent_size, const gchar * child_size) { guint psize = (guint) g_ascii_strtoull (parent_size, NULL, 10U); guint csize = (guint) g_ascii_strtoull (child_size, NULL, 10U); csize = (csize * psize) / 100U; return g_strdup_printf ("%u%%", csize); } static TtmlStyleSet * ttml_style_set_inherit (TtmlStyleSet * parent, TtmlStyleSet * child) { TtmlStyleSet *ret = NULL; GHashTableIter iter; gpointer attr_name, attr_value; if (child) { ret = ttml_style_set_copy (child); } else { ret = ttml_style_set_new (); } if (!parent) return ret; g_hash_table_iter_init (&iter, parent->table); while (g_hash_table_iter_next (&iter, &attr_name, &attr_value)) { /* In TTML, if an element which has a defined fontSize is the child of an * element that also has a defined fontSize, the child's font size is * relative to that of its parent. If its parent doesn't have a defined * fontSize, then the child's fontSize is relative to the document's cell * size. Therefore, if the former is true, we calculate the value of * fontSize based on the parent's fontSize; otherwise, we simply keep * the value defined in the child's style set. */ if (g_strcmp0 ((const gchar *) attr_name, "fontSize") == 0 && ttml_style_set_contains_attr (ret, "fontSize")) { const gchar *original_child_font_size = ttml_style_set_get_attr (ret, "fontSize"); gchar *scaled_child_font_size = ttml_get_relative_font_size ((const gchar *) attr_value, original_child_font_size); GST_CAT_LOG (ttmlparse_debug, "Calculated font size: %s", scaled_child_font_size); ttml_style_set_add_attr (ret, (const gchar *) attr_name, scaled_child_font_size); g_free (scaled_child_font_size); } /* Not all styling attributes are inherited in TTML. */ if (g_strcmp0 ((const gchar *) attr_name, "backgroundColor") != 0 && g_strcmp0 ((const gchar *) attr_name, "origin") != 0 && g_strcmp0 ((const gchar *) attr_name, "extent") != 0 && g_strcmp0 ((const gchar *) attr_name, "displayAlign") != 0 && g_strcmp0 ((const gchar *) attr_name, "overflow") != 0 && g_strcmp0 ((const gchar *) attr_name, "padding") != 0 && g_strcmp0 ((const gchar *) attr_name, "writingMode") != 0 && g_strcmp0 ((const gchar *) attr_name, "showBackground") != 0 && g_strcmp0 ((const gchar *) attr_name, "unicodeBidi") != 0) { if (!ttml_style_set_contains_attr (ret, (const gchar *) attr_name)) { ttml_style_set_add_attr (ret, (const gchar *) attr_name, (const gchar *) attr_value); } } } return ret; } /* * Returns TRUE iff @element1 and @element2 reference the same set of styles. * If neither @element1 nor @element2 reference any styles, they are considered * to have matching styling and, hence, TRUE is returned. */ static gboolean ttml_element_styles_match (TtmlElement * element1, TtmlElement * element2) { const gchar *const *strv; gint i; if (!element1 || !element2 || (!element1->styles && element2->styles) || (element1->styles && !element2->styles)) return FALSE; if (!element1->styles && !element2->styles) return TRUE; strv = (const gchar * const *) element2->styles; if (g_strv_length (element1->styles) != g_strv_length (element2->styles)) return FALSE; for (i = 0; i < g_strv_length (element1->styles); ++i) { if (!g_strv_contains (strv, element1->styles[i])) return FALSE; } return TRUE; } static gchar * ttml_get_element_type_string (TtmlElement * element) { switch (element->type) { case TTML_ELEMENT_TYPE_STYLE: return g_strdup ("<style>"); break; case TTML_ELEMENT_TYPE_REGION: return g_strdup ("<region>"); break; case TTML_ELEMENT_TYPE_BODY: return g_strdup ("<body>"); break; case TTML_ELEMENT_TYPE_DIV: return g_strdup ("<div>"); break; case TTML_ELEMENT_TYPE_P: return g_strdup ("<p>"); break; case TTML_ELEMENT_TYPE_SPAN: return g_strdup ("<span>"); break; case TTML_ELEMENT_TYPE_ANON_SPAN: return g_strdup ("<anon-span>"); break; case TTML_ELEMENT_TYPE_BR: return g_strdup ("<br>"); break; default: return g_strdup ("Unknown"); break; } } /* Merge styles referenced by an element. */ static gboolean ttml_resolve_styles (GNode * node, gpointer data) { TtmlStyleSet *tmp = NULL; TtmlElement *element, *style; GHashTable *styles_table; gchar *type_string; guint i; styles_table = (GHashTable *) data; element = node->data; type_string = ttml_get_element_type_string (element); GST_CAT_LOG (ttmlparse_debug, "Element type: %s", type_string); g_free (type_string); if (!element->styles) return FALSE; for (i = 0; i < g_strv_length (element->styles); ++i) { tmp = element->style_set; style = g_hash_table_lookup (styles_table, element->styles[i]); if (style) { GST_CAT_LOG (ttmlparse_debug, "Merging style %s...", element->styles[i]); element->style_set = ttml_style_set_merge (element->style_set, style->style_set); ttml_style_set_delete (tmp); } else { GST_CAT_WARNING (ttmlparse_debug, "Element references an unknown style (%s)", element->styles[i]); } } GST_CAT_LOG (ttmlparse_debug, "Style set after merging:"); ttml_style_set_print (element->style_set); return FALSE; } static void ttml_resolve_referenced_styles (GList * trees, GHashTable * styles_table) { GList *tree; for (tree = g_list_first (trees); tree; tree = tree->next) { GNode *root = (GNode *) tree->data; g_node_traverse (root, G_PRE_ORDER, G_TRAVERSE_ALL, -1, ttml_resolve_styles, styles_table); } } /* Inherit styling attributes from parent. */ static gboolean ttml_inherit_styles (GNode * node, gpointer data) { TtmlStyleSet *tmp = NULL; TtmlElement *element, *parent; gchar *type_string; element = node->data; type_string = ttml_get_element_type_string (element); GST_CAT_LOG (ttmlparse_debug, "Element type: %s", type_string); g_free (type_string); if (node->parent) { parent = node->parent->data; if (parent->style_set) { tmp = element->style_set; if (element->type == TTML_ELEMENT_TYPE_ANON_SPAN || element->type == TTML_ELEMENT_TYPE_BR) { element->style_set = ttml_style_set_merge (parent->style_set, element->style_set); element->styles = g_strdupv (parent->styles); } else { element->style_set = ttml_style_set_inherit (parent->style_set, element->style_set); } ttml_style_set_delete (tmp); } } GST_CAT_LOG (ttmlparse_debug, "Style set after inheriting:"); ttml_style_set_print (element->style_set); return FALSE; } static void ttml_inherit_element_styles (GList * trees) { GList *tree; for (tree = g_list_first (trees); tree; tree = tree->next) { GNode *root = (GNode *) tree->data; g_node_traverse (root, G_PRE_ORDER, G_TRAVERSE_ALL, -1, ttml_inherit_styles, NULL); } } /* If whitespace_mode isn't explicitly set for this element, inherit from its * parent. If this element is the root of the tree, set whitespace_mode to * that of the overall document. */ static gboolean ttml_inherit_element_whitespace_mode (GNode * node, gpointer data) { TtmlWhitespaceMode *doc_mode = (TtmlWhitespaceMode *) data; TtmlElement *element = node->data; TtmlElement *parent; if (element->whitespace_mode != TTML_WHITESPACE_MODE_NONE) return FALSE; if (G_NODE_IS_ROOT (node)) { element->whitespace_mode = *doc_mode; return FALSE; } parent = node->parent->data; element->whitespace_mode = parent->whitespace_mode; return FALSE; } static void ttml_inherit_whitespace_mode (GNode * tree, TtmlWhitespaceMode doc_mode) { g_node_traverse (tree, G_PRE_ORDER, G_TRAVERSE_ALL, -1, ttml_inherit_element_whitespace_mode, &doc_mode); } static gboolean ttml_free_node_data (GNode * node, gpointer data) { TtmlElement *element = node->data; ttml_delete_element (element); return FALSE; } static void ttml_delete_tree (GNode * tree) { g_node_traverse (tree, G_PRE_ORDER, G_TRAVERSE_ALL, -1, ttml_free_node_data, NULL); g_node_destroy (tree); } typedef struct { GstClockTime begin; GstClockTime end; } ClipWindow; static gboolean ttml_clip_element_period (GNode * node, gpointer data) { TtmlElement *element = node->data; ClipWindow *window = data; if (!GST_CLOCK_TIME_IS_VALID (element->begin)) { return FALSE; } if (element->begin > window->end || element->end < window->begin) { ttml_delete_tree (node); node = NULL; return FALSE; } element->begin = MAX (element->begin, window->begin); element->end = MIN (element->end, window->end); return FALSE; } static void ttml_apply_time_window (GNode * tree, GstClockTime window_begin, GstClockTime window_end) { ClipWindow window; window.begin = window_begin; window.end = window_end; g_node_traverse (tree, G_PRE_ORDER, G_TRAVERSE_ALL, -1, ttml_clip_element_period, &window); } static gboolean ttml_resolve_element_timings (GNode * node, gpointer data) { TtmlElement *element, *leaf; leaf = element = node->data; if (GST_CLOCK_TIME_IS_VALID (leaf->begin) && GST_CLOCK_TIME_IS_VALID (leaf->end)) { GST_CAT_LOG (ttmlparse_debug, "Leaf node already has timing."); return FALSE; } /* Inherit timings from ancestor. */ while (node->parent && !GST_CLOCK_TIME_IS_VALID (element->begin)) { node = node->parent; element = node->data; } if (!GST_CLOCK_TIME_IS_VALID (element->begin)) { GST_CAT_WARNING (ttmlparse_debug, "No timing found for element; setting to Root Temporal Extent."); leaf->begin = 0; leaf->end = NSECONDS_IN_DAY; } else { leaf->begin = element->begin; leaf->end = element->end; GST_CAT_LOG (ttmlparse_debug, "Leaf begin: %" GST_TIME_FORMAT, GST_TIME_ARGS (leaf->begin)); GST_CAT_LOG (ttmlparse_debug, "Leaf end: %" GST_TIME_FORMAT, GST_TIME_ARGS (leaf->end)); } return FALSE; } static void ttml_resolve_timings (GNode * tree) { g_node_traverse (tree, G_PRE_ORDER, G_TRAVERSE_LEAVES, -1, ttml_resolve_element_timings, NULL); } static gboolean ttml_resolve_leaf_region (GNode * node, gpointer data) { TtmlElement *element, *leaf; leaf = element = node->data; while (node->parent && !element->region) { node = node->parent; element = node->data; } if (element->region) { leaf->region = g_strdup (element->region); GST_CAT_LOG (ttmlparse_debug, "Leaf region: %s", leaf->region); } else { GST_CAT_WARNING (ttmlparse_debug, "No region found above leaf element."); } return FALSE; } static void ttml_resolve_regions (GNode * tree) { g_node_traverse (tree, G_PRE_ORDER, G_TRAVERSE_LEAVES, -1, ttml_resolve_leaf_region, NULL); } typedef struct { GstClockTime start_time; GstClockTime next_transition_time; } TrState; static gboolean ttml_update_transition_time (GNode * node, gpointer data) { TtmlElement *element = node->data; TrState *state = (TrState *) data; if ((element->begin < state->next_transition_time) && (!GST_CLOCK_TIME_IS_VALID (state->start_time) || (element->begin > state->start_time))) { state->next_transition_time = element->begin; GST_CAT_LOG (ttmlparse_debug, "Updating next transition time to element begin time (%" GST_TIME_FORMAT ")", GST_TIME_ARGS (state->next_transition_time)); return FALSE; } if ((element->end < state->next_transition_time) && (element->end > state->start_time)) { state->next_transition_time = element->end; GST_CAT_LOG (ttmlparse_debug, "Updating next transition time to element end time (%" GST_TIME_FORMAT ")", GST_TIME_ARGS (state->next_transition_time)); } return FALSE; } /* Return details about the next transition after @time. */ static GstClockTime ttml_find_next_transition (GList * trees, GstClockTime time) { TrState state; state.start_time = time; state.next_transition_time = GST_CLOCK_TIME_NONE; for (trees = g_list_first (trees); trees; trees = trees->next) { GNode *tree = (GNode *) trees->data; g_node_traverse (tree, G_PRE_ORDER, G_TRAVERSE_ALL, -1, ttml_update_transition_time, &state); } GST_CAT_LOG (ttmlparse_debug, "Next transition is at %" GST_TIME_FORMAT, GST_TIME_ARGS (state.next_transition_time)); return state.next_transition_time; } /* Remove nodes from tree that are not visible at @time. */ static GNode * ttml_remove_nodes_by_time (GNode * node, GstClockTime time) { GNode *child, *next_child; TtmlElement *element; element = node->data; child = node->children; next_child = child ? child->next : NULL; while (child) { ttml_remove_nodes_by_time (child, time); child = next_child; next_child = child ? child->next : NULL; } if (!node->children && ((element->begin > time) || (element->end <= time))) { ttml_delete_tree (node); node = NULL; } return node; } /* Return a list of trees containing the elements and their ancestors that are * visible at @time. */ static GList * ttml_get_active_trees (GList * element_trees, GstClockTime time) { GList *tree; GList *ret = NULL; for (tree = g_list_first (element_trees); tree; tree = tree->next) { GNode *root = g_node_copy_deep ((GNode *) tree->data, ttml_copy_tree_element, NULL); GST_CAT_LOG (ttmlparse_debug, "There are %u nodes in tree.", g_node_n_nodes (root, G_TRAVERSE_ALL)); root = ttml_remove_nodes_by_time (root, time); if (root) { GST_CAT_LOG (ttmlparse_debug, "After filtering there are %u nodes in tree.", g_node_n_nodes (root, G_TRAVERSE_ALL)); ret = g_list_append (ret, root); } else { GST_CAT_LOG (ttmlparse_debug, "All elements have been filtered from tree."); } } GST_CAT_DEBUG (ttmlparse_debug, "There are %u trees in returned list.", g_list_length (ret)); return ret; } static GList * ttml_create_scenes (GList * region_trees) { TtmlScene *cur_scene = NULL; GList *output_scenes = NULL; GList *active_trees = NULL; GstClockTime timestamp = GST_CLOCK_TIME_NONE; while ((timestamp = ttml_find_next_transition (region_trees, timestamp)) != GST_CLOCK_TIME_NONE) { GST_CAT_LOG (ttmlparse_debug, "Next transition found at time %" GST_TIME_FORMAT, GST_TIME_ARGS (timestamp)); if (cur_scene) { cur_scene->end = timestamp; output_scenes = g_list_append (output_scenes, cur_scene); } active_trees = ttml_get_active_trees (region_trees, timestamp); GST_CAT_LOG (ttmlparse_debug, "There will be %u active regions after " "transition", g_list_length (active_trees)); if (active_trees) { cur_scene = g_new0 (TtmlScene, 1); cur_scene->begin = timestamp; cur_scene->trees = active_trees; } else { cur_scene = NULL; } } return output_scenes; } /* Handle element whitespace in accordance with section 7.2.3 of the TTML * specification. Specifically, this function implements the * white-space-collapse="true" and linefeed-treatment="treat-as-space" * behaviours. Note that stripping of whitespace at the start and end of line * areas (suppress-at-line-break="auto" and * white-space-treatment="ignore-if-surrounding-linefeed" behaviours) can only * be done by the renderer once the text from multiple elements has been laid * out in line areas. */ static gboolean ttml_handle_element_whitespace (GNode * node, gpointer data) { TtmlElement *element = node->data; guint space_count = 0; guint textlen; gchar *c; if (!element->text || (element->type == TTML_ELEMENT_TYPE_BR) || (element->whitespace_mode == TTML_WHITESPACE_MODE_PRESERVE)) { return FALSE; } textlen = strlen (element->text); for (c = element->text; TRUE; c = g_utf8_next_char (c)) { gchar buf[6] = { 0 }; gunichar u = g_utf8_get_char (c); gint nbytes = g_unichar_to_utf8 (u, buf); /* Replace each newline or tab with a space. */ if (nbytes == 1 && (buf[0] == TTML_CHAR_LF || buf[0] == TTML_CHAR_TAB)) { *c = ' '; buf[0] = TTML_CHAR_SPACE; } /* Collapse runs of whitespace. */ if (nbytes == 1 && (buf[0] == TTML_CHAR_SPACE || buf[0] == TTML_CHAR_CR)) { ++space_count; } else { if (space_count > 1) { gchar *new_head = c - space_count + 1; g_strlcpy (new_head, c, textlen); c = new_head; } space_count = 0; if (nbytes == 1 && buf[0] == TTML_CHAR_NULL) break; } } return FALSE; } static void ttml_handle_whitespace (GNode * tree) { g_node_traverse (tree, G_PRE_ORDER, G_TRAVERSE_LEAVES, -1, ttml_handle_element_whitespace, NULL); } static GNode * ttml_filter_content_nodes (GNode * node) { GNode *child, *next_child; TtmlElement *element = node->data; TtmlElement *parent = node->parent ? node->parent->data : NULL; child = node->children; next_child = child ? child->next : NULL; while (child) { ttml_filter_content_nodes (child); child = next_child; next_child = child ? child->next : NULL; } /* Only text content in <p>s and <span>s is significant. */ if (element->type == TTML_ELEMENT_TYPE_ANON_SPAN && parent->type != TTML_ELEMENT_TYPE_P && parent->type != TTML_ELEMENT_TYPE_SPAN) { ttml_delete_element (element); g_node_destroy (node); node = NULL; } return node; } /* Store in @table child elements of @node with name @element_name. A child * element with the same ID as an existing entry in @table will overwrite the * existing entry. */ static void ttml_store_unique_children (xmlNodePtr node, const gchar * element_name, GHashTable * table) { xmlNodePtr ptr; for (ptr = node->children; ptr; ptr = ptr->next) { if (xmlStrcmp (ptr->name, (const xmlChar *) element_name) == 0) { TtmlElement *element = ttml_parse_element (ptr); gboolean new_key; if (element) { new_key = g_hash_table_insert (table, g_strdup (element->id), element); if (!new_key) GST_CAT_WARNING (ttmlparse_debug, "Document contains two %s elements with the same ID (\"%s\").", element_name, element->id); } } } } /* Parse style and region elements from @head and store in their respective * hash tables for future reference. */ static void ttml_parse_head (xmlNodePtr head, GHashTable * styles_table, GHashTable * regions_table) { xmlNodePtr node; for (node = head->children; node; node = node->next) { if (xmlStrcmp (node->name, (const xmlChar *) "styling") == 0) ttml_store_unique_children (node, "style", styles_table); if (xmlStrcmp (node->name, (const xmlChar *) "layout") == 0) ttml_store_unique_children (node, "region", regions_table); } } /* Remove nodes that do not belong to @region, or are not an ancestor of a node * belonging to @region. */ static GNode * ttml_remove_nodes_by_region (GNode * node, const gchar * region) { GNode *child, *next_child; TtmlElement *element; element = node->data; child = node->children; next_child = child ? child->next : NULL; while (child) { ttml_remove_nodes_by_region (child, region); child = next_child; next_child = child ? child->next : NULL; } if ((element->type == TTML_ELEMENT_TYPE_ANON_SPAN || element->type != TTML_ELEMENT_TYPE_BR) && element->region && (g_strcmp0 (element->region, region) != 0)) { ttml_delete_element (element); g_node_destroy (node); return NULL; } if (element->type != TTML_ELEMENT_TYPE_ANON_SPAN && element->type != TTML_ELEMENT_TYPE_BR && !node->children) { ttml_delete_element (element); g_node_destroy (node); return NULL; } return node; } static TtmlElement * ttml_copy_element (const TtmlElement * element) { TtmlElement *ret = g_new0 (TtmlElement, 1); ret->type = element->type; if (element->id) ret->id = g_strdup (element->id); ret->whitespace_mode = element->whitespace_mode; if (element->styles) ret->styles = g_strdupv (element->styles); if (element->region) ret->region = g_strdup (element->region); ret->begin = element->begin; ret->end = element->end; if (element->style_set) ret->style_set = ttml_style_set_copy (element->style_set); if (element->text) ret->text = g_strdup (element->text); return ret; } static gpointer ttml_copy_tree_element (gconstpointer src, gpointer data) { return ttml_copy_element ((TtmlElement *) src); } /* Split the body tree into a set of trees, each containing only the elements * belonging to a single region. Returns a list of trees, one per region, each * with the corresponding region element at its root. */ static GList * ttml_split_body_by_region (GNode * body, GHashTable * regions) { GHashTableIter iter; gpointer key, value; GList *ret = NULL; g_hash_table_iter_init (&iter, regions); while (g_hash_table_iter_next (&iter, &key, &value)) { gchar *region_name = (gchar *) key; TtmlElement *region = (TtmlElement *) value; GNode *region_node = g_node_new (ttml_copy_element (region)); GNode *body_copy = g_node_copy_deep (body, ttml_copy_tree_element, NULL); GST_CAT_DEBUG (ttmlparse_debug, "Creating tree for region %s", region_name); GST_CAT_LOG (ttmlparse_debug, "Copy of body has %u nodes.", g_node_n_nodes (body_copy, G_TRAVERSE_ALL)); body_copy = ttml_remove_nodes_by_region (body_copy, region_name); if (body_copy) { GST_CAT_LOG (ttmlparse_debug, "Copy of body now has %u nodes.", g_node_n_nodes (body_copy, G_TRAVERSE_ALL)); /* Reparent tree to region node. */ g_node_prepend (region_node, body_copy); } GST_CAT_LOG (ttmlparse_debug, "Final tree has %u nodes.", g_node_n_nodes (region_node, G_TRAVERSE_ALL)); ret = g_list_append (ret, region_node); } GST_CAT_DEBUG (ttmlparse_debug, "Returning %u trees.", g_list_length (ret)); return ret; } static gint ttml_add_text_to_buffer (GstBuffer * buf, const gchar * text) { GstMemory *mem; GstMapInfo map; guint ret; if (gst_buffer_n_memory (buf) == gst_buffer_get_max_memory ()) return -1; mem = gst_allocator_alloc (NULL, strlen (text) + 1, NULL); if (!gst_memory_map (mem, &map, GST_MAP_WRITE)) GST_CAT_ERROR (ttmlparse_debug, "Failed to map memory."); g_strlcpy ((gchar *) map.data, text, map.size); GST_CAT_DEBUG (ttmlparse_debug, "Inserted following text into buffer: \"%s\"", (gchar *) map.data); gst_memory_unmap (mem, &map); ret = gst_buffer_n_memory (buf); gst_buffer_insert_memory (buf, -1, mem); return ret; } /* Create a GstSubtitleElement from @element, add it to @block, and insert its * associated text in @buf. */ static gboolean ttml_add_element (GstSubtitleBlock * block, TtmlElement * element, GstBuffer * buf, guint cellres_x, guint cellres_y) { GstSubtitleStyleSet *element_style = NULL; guint buffer_index; GstSubtitleElement *sub_element = NULL; buffer_index = ttml_add_text_to_buffer (buf, element->text); if (buffer_index == -1) { GST_CAT_WARNING (ttmlparse_debug, "Reached maximum element count for buffer - discarding element."); return FALSE; } GST_CAT_DEBUG (ttmlparse_debug, "Inserted text at index %u in GstBuffer.", buffer_index); element_style = gst_subtitle_style_set_new (); ttml_update_style_set (element_style, element->style_set, cellres_x, cellres_y); sub_element = gst_subtitle_element_new (element_style, buffer_index, (element->whitespace_mode != TTML_WHITESPACE_MODE_PRESERVE)); gst_subtitle_block_add_element (block, sub_element); GST_CAT_DEBUG (ttmlparse_debug, "Added element to block; there are now %u elements in the block.", gst_subtitle_block_get_element_count (block)); return TRUE; } /* Return TRUE if @color is totally transparent. */ static gboolean ttml_color_is_transparent (const GstSubtitleColor * color) { if (!color) return FALSE; else return (color->a == 0); } /* Blend @color2 over @color1 and return the resulting color. This is currently * a dummy implementation that simply returns color2 as long as it's * not fully transparent. */ /* TODO: Implement actual blending of colors. */ static GstSubtitleColor ttml_blend_colors (GstSubtitleColor color1, GstSubtitleColor color2) { if (ttml_color_is_transparent (&color2)) return color1; else return color2; } static void ttml_warn_of_mispositioned_element (TtmlElement * element) { gchar *type = ttml_get_element_type_string (element); GST_CAT_WARNING (ttmlparse_debug, "Ignoring illegally positioned %s element.", type); g_free (type); } /* Create the subtitle region and its child blocks and elements for @tree, * inserting element text in @buf. Ownership of created region is transferred * to caller. */ static GstSubtitleRegion * ttml_create_subtitle_region (GNode * tree, GstBuffer * buf, guint cellres_x, guint cellres_y) { GstSubtitleRegion *region = NULL; GstSubtitleStyleSet *region_style; GstSubtitleColor block_color; TtmlElement *element; GNode *node; element = tree->data; /* Region element */ region_style = gst_subtitle_style_set_new (); ttml_update_style_set (region_style, element->style_set, cellres_x, cellres_y); region = gst_subtitle_region_new (region_style); node = tree->children; if (!node) return region; element = node->data; /* Body element */ block_color = ttml_parse_colorstring (ttml_style_set_get_attr (element->style_set, "backgroundColor")); for (node = node->children; node; node = node->next) { GNode *p_node; GstSubtitleColor div_color; element = node->data; if (element->type != TTML_ELEMENT_TYPE_DIV) { ttml_warn_of_mispositioned_element (element); continue; } div_color = ttml_parse_colorstring (ttml_style_set_get_attr (element->style_set, "backgroundColor")); block_color = ttml_blend_colors (block_color, div_color); for (p_node = node->children; p_node; p_node = p_node->next) { GstSubtitleBlock *block = NULL; GstSubtitleStyleSet *block_style; GNode *content_node; GstSubtitleColor p_color; element = p_node->data; if (element->type != TTML_ELEMENT_TYPE_P) { ttml_warn_of_mispositioned_element (element); continue; } p_color = ttml_parse_colorstring (ttml_style_set_get_attr (element->style_set, "backgroundColor")); block_color = ttml_blend_colors (block_color, p_color); block_style = gst_subtitle_style_set_new (); ttml_update_style_set (block_style, element->style_set, cellres_x, cellres_y); block_style->background_color = block_color; block = gst_subtitle_block_new (block_style); for (content_node = p_node->children; content_node; content_node = content_node->next) { GNode *anon_node; element = content_node->data; if (element->type == TTML_ELEMENT_TYPE_BR || element->type == TTML_ELEMENT_TYPE_ANON_SPAN) { if (!ttml_add_element (block, element, buf, cellres_x, cellres_y)) GST_CAT_WARNING (ttmlparse_debug, "Failed to add element to buffer."); } else if (element->type == TTML_ELEMENT_TYPE_SPAN) { /* Loop through anon-span children of this span. */ for (anon_node = content_node->children; anon_node; anon_node = anon_node->next) { element = anon_node->data; if (element->type == TTML_ELEMENT_TYPE_BR || element->type == TTML_ELEMENT_TYPE_ANON_SPAN) { if (!ttml_add_element (block, element, buf, cellres_x, cellres_y)) GST_CAT_WARNING (ttmlparse_debug, "Failed to add element to buffer."); } else { ttml_warn_of_mispositioned_element (element); } } } else { ttml_warn_of_mispositioned_element (element); } } if (gst_subtitle_block_get_element_count (block) > 0) { gst_subtitle_region_add_block (region, block); GST_CAT_DEBUG (ttmlparse_debug, "Added block to region; there are now %u blocks in the region.", gst_subtitle_region_get_block_count (region)); } else { gst_subtitle_block_unref (block); } } } return region; } /* For each scene, create data objects to describe the layout and styling of * that scene and attach it as metadata to the GstBuffer that will be used to * carry that scene's text. */ static void ttml_attach_scene_metadata (GList * scenes, guint cellres_x, guint cellres_y) { GList *scene_entry; for (scene_entry = g_list_first (scenes); scene_entry; scene_entry = scene_entry->next) { TtmlScene *scene = scene_entry->data; GList *region_tree; GPtrArray *regions = g_ptr_array_new_with_free_func ( (GDestroyNotify) gst_subtitle_region_unref); scene->buf = gst_buffer_new (); GST_BUFFER_PTS (scene->buf) = scene->begin; GST_BUFFER_DURATION (scene->buf) = (scene->end - scene->begin); for (region_tree = g_list_first (scene->trees); region_tree; region_tree = region_tree->next) { GNode *tree = (GNode *) region_tree->data; GstSubtitleRegion *region; region = ttml_create_subtitle_region (tree, scene->buf, cellres_x, cellres_y); if (region) g_ptr_array_add (regions, region); } gst_buffer_add_subtitle_meta (scene->buf, regions); } } static GList * create_buffer_list (GList * scenes) { GList *ret = NULL; while (scenes) { TtmlScene *scene = scenes->data; ret = g_list_prepend (ret, gst_buffer_ref (scene->buf)); scenes = scenes->next; } return g_list_reverse (ret); } static void ttml_delete_scene (TtmlScene * scene) { if (scene->trees) g_list_free_full (scene->trees, (GDestroyNotify) ttml_delete_tree); if (scene->buf) gst_buffer_unref (scene->buf); g_free (scene); } static void ttml_assign_region_times (GList * region_trees, GstClockTime doc_begin, GstClockTime doc_duration) { GList *tree; for (tree = g_list_first (region_trees); tree; tree = tree->next) { GNode *region_node = (GNode *) tree->data; TtmlElement *region = (TtmlElement *) region_node->data; const gchar *show_background_value = ttml_style_set_get_attr (region->style_set, "showBackground"); gboolean always_visible = (g_strcmp0 (show_background_value, "whenActive") != 0); GstSubtitleColor region_color = { 0, 0, 0, 0 }; if (ttml_style_set_contains_attr (region->style_set, "backgroundColor")) region_color = ttml_parse_colorstring (ttml_style_set_get_attr (region->style_set, "backgroundColor")); if (always_visible && !ttml_color_is_transparent (®ion_color)) { GST_CAT_DEBUG (ttmlparse_debug, "Assigning times to region."); /* If the input XML document was not encapsulated in a container that * provides timing information for the document as a whole (i.e., its * PTS and duration) and the region background should be always visible, * set region start time to 0 and end time to 24 hours. This ensures that * regions with showBackground="always" are visible for the entirety of * any real-world stream. */ region->begin = (doc_begin != GST_CLOCK_TIME_NONE) ? doc_begin : 0; region->end = (doc_duration != GST_CLOCK_TIME_NONE) ? region->begin + doc_duration : NSECONDS_IN_DAY; } } } /* * Promotes @node to the position of its parent, setting the prev, next and * parent pointers of @node to that of its original parent. The replaced parent * is freed. Should be called only on nodes that are the sole child of their * parent, otherwise sibling nodes may be leaked. */ static void ttml_promote_node (GNode * node) { GNode *parent_node = node->parent; TtmlElement *parent_element; if (!parent_node) return; parent_element = (TtmlElement *) parent_node->data; node->prev = parent_node->prev; if (!node->prev) parent_node->parent->children = node; else node->prev->next = node; node->next = parent_node->next; if (node->next) node->next->prev = node; node->parent = parent_node->parent; parent_node->prev = parent_node->next = NULL; parent_node->parent = parent_node->children = NULL; g_node_destroy (parent_node); ttml_delete_element (parent_element); } /* * Returns TRUE if @element is of a type that can be joined with another * joinable element. */ static gboolean ttml_element_is_joinable (TtmlElement * element) { return element->type == TTML_ELEMENT_TYPE_ANON_SPAN || element->type == TTML_ELEMENT_TYPE_BR; } /* Joins adjacent inline element in @tree that have the same styling. */ static void ttml_join_region_tree_inline_elements (GNode * tree) { GNode *n1, *n2; for (n1 = tree; n1; n1 = n1->next) { if (n1->children) { TtmlElement *element = (TtmlElement *) n1->data; ttml_join_region_tree_inline_elements (n1->children); if (element->type == TTML_ELEMENT_TYPE_SPAN && g_node_n_children (n1) == 1) { GNode *child = n1->children; if (n1 == tree) tree = child; ttml_promote_node (child); n1 = child; } } } n1 = tree; n2 = tree->next; while (n1 && n2) { TtmlElement *e1 = (TtmlElement *) n1->data; TtmlElement *e2 = (TtmlElement *) n2->data; if (ttml_element_is_joinable (e1) && ttml_element_is_joinable (e2) && ttml_element_styles_match (e1, e2)) { gchar *tmp = e1->text; GST_CAT_LOG (ttmlparse_debug, "Joining adjacent element text \"%s\" & \"%s\"", e1->text, e2->text); e1->text = g_strconcat (e1->text, e2->text, NULL); e1->type = TTML_ELEMENT_TYPE_ANON_SPAN; g_free (tmp); ttml_delete_element (e2); g_node_destroy (n2); n2 = n1->next; } else { n1 = n2; n2 = n2->next; } } } static void ttml_join_inline_elements (GList * scenes) { GList *scene_entry; for (scene_entry = g_list_first (scenes); scene_entry; scene_entry = scene_entry->next) { TtmlScene *scene = scene_entry->data; GList *region_tree; for (region_tree = g_list_first (scene->trees); region_tree; region_tree = region_tree->next) { GNode *tree = (GNode *) region_tree->data; ttml_join_region_tree_inline_elements (tree); } } } static xmlNodePtr ttml_find_child (xmlNodePtr parent, const gchar * name) { xmlNodePtr child = parent->children; while (child && xmlStrcmp (child->name, (const xmlChar *) name) != 0) child = child->next; return child; } #define XML_START_TAG "<?xml" #define TTML_END_TAG "</tt>" guint ttml_parse (const gchar * input, GstClockTime begin, GstClockTime duration, GList ** parsed) { xmlDocPtr doc; xmlNodePtr root_node, head_node, body_node; GHashTable *styles_table, *regions_table; GList *output_buffers = NULL; gchar *value; guint cellres_x, cellres_y; TtmlWhitespaceMode doc_whitespace_mode = TTML_WHITESPACE_MODE_DEFAULT; guint consumed = 0; guint start_offset = 0; gchar *start_xml, *end_tt; g_return_val_if_fail (parsed != NULL, 0); *parsed = NULL; if (!g_utf8_validate (input, -1, NULL)) { GST_CAT_ERROR (ttmlparse_debug, "Input isn't valid UTF-8."); return 0; } GST_CAT_LOG (ttmlparse_debug, "Input:\n%s", input); start_xml = g_strstr_len (input, strlen (input), XML_START_TAG); end_tt = g_strstr_len (input, strlen (input), TTML_END_TAG); if (!start_xml || !end_tt) { GST_CAT_DEBUG (ttmlparse_debug, "Need more data"); return 0; } consumed = end_tt - input + strlen (TTML_END_TAG); start_offset = start_xml - input; styles_table = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, (GDestroyNotify) ttml_delete_element); regions_table = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, (GDestroyNotify) ttml_delete_element); /* Parse input. */ doc = xmlReadMemory (start_xml, consumed - start_offset, "any_doc_name", NULL, 0); if (!doc) { GST_CAT_ERROR (ttmlparse_debug, "Failed to parse document."); return 0; } root_node = xmlDocGetRootElement (doc); if (xmlStrcmp (root_node->name, (const xmlChar *) "tt") != 0) { GST_CAT_ERROR (ttmlparse_debug, "Root element of document is not tt:tt."); xmlFreeDoc (doc); return 0; } if ((value = ttml_get_xml_property (root_node, "cellResolution"))) { gchar *ptr = value; cellres_x = (guint) g_ascii_strtoull (ptr, &ptr, 10U); cellres_y = (guint) g_ascii_strtoull (ptr, NULL, 10U); g_free (value); } else { cellres_x = DEFAULT_CELLRES_X; cellres_y = DEFAULT_CELLRES_Y; } GST_CAT_DEBUG (ttmlparse_debug, "cellres_x: %u cellres_y: %u", cellres_x, cellres_y); if ((value = ttml_get_xml_property (root_node, "space"))) { if (g_strcmp0 (value, "preserve") == 0) { GST_CAT_DEBUG (ttmlparse_debug, "Preserving whitespace..."); doc_whitespace_mode = TTML_WHITESPACE_MODE_PRESERVE; } g_free (value); } if (!(head_node = ttml_find_child (root_node, "head"))) { GST_CAT_ERROR (ttmlparse_debug, "No <head> element found."); xmlFreeDoc (doc); return 0; } ttml_parse_head (head_node, styles_table, regions_table); if ((body_node = ttml_find_child (root_node, "body"))) { GNode *body_tree; GList *region_trees = NULL; GList *scenes = NULL; body_tree = ttml_parse_body (body_node); GST_CAT_LOG (ttmlparse_debug, "body_tree tree contains %u nodes.", g_node_n_nodes (body_tree, G_TRAVERSE_ALL)); GST_CAT_LOG (ttmlparse_debug, "body_tree tree height is %u", g_node_max_height (body_tree)); ttml_inherit_whitespace_mode (body_tree, doc_whitespace_mode); ttml_handle_whitespace (body_tree); ttml_filter_content_nodes (body_tree); if (GST_CLOCK_TIME_IS_VALID (begin) && GST_CLOCK_TIME_IS_VALID (duration)) ttml_apply_time_window (body_tree, begin, begin + duration); ttml_resolve_timings (body_tree); ttml_resolve_regions (body_tree); region_trees = ttml_split_body_by_region (body_tree, regions_table); ttml_resolve_referenced_styles (region_trees, styles_table); ttml_inherit_element_styles (region_trees); ttml_assign_region_times (region_trees, begin, duration); scenes = ttml_create_scenes (region_trees); GST_CAT_LOG (ttmlparse_debug, "There are %u scenes in all.", g_list_length (scenes)); ttml_join_inline_elements (scenes); ttml_attach_scene_metadata (scenes, cellres_x, cellres_y); output_buffers = create_buffer_list (scenes); g_list_free_full (scenes, (GDestroyNotify) ttml_delete_scene); g_list_free_full (region_trees, (GDestroyNotify) ttml_delete_tree); ttml_delete_tree (body_tree); } xmlFreeDoc (doc); g_hash_table_destroy (styles_table); g_hash_table_destroy (regions_table); *parsed = output_buffers; return consumed; }