/* * GStreamer * Copyright (C) 2006 James Livingston * Copyright (C) 2008 Vincent Penquerc'h * * 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-katetag * @see_also: #oggdemux, #oggmux, #kateparse, #GstTagSetter * @short_description: retags kate streams * * * * The katetag element can change the tag contained within a raw * kate stream. Specifically, it modifies the comments header packet * of the kate stream, as well as the language and category of the * kate stream. * * * The element will also process the stream as the #kateparse element does * so it can be used when remuxing an Ogg Kate stream, without additional * elements. * * * Applications can set the tags to write using the #GstTagSetter interface. * Tags contained within the kate stream will be picked up * automatically (and merged according to the merge mode set via the tag * setter interface). * * Example pipelines * * This element is only useful with gst-launch for modifying the language * and/or category (which are properties of the stream located in the kate * beginning of stream header), because it does not support setting the tags * on a #GstTagSetter interface. Conceptually, the element will usually be * used like: * * gst-launch -v filesrc location=foo.ogg ! oggdemux ! katetag ! oggmux ! filesink location=bar.ogg * * * * This pipeline will set the language and category of the stream to the * given values: * * gst-launch -v filesrc location=foo.ogg ! oggdemux ! katetag language=pt_BR category=subtitles ! oggmux ! filesink location=bar.ogg * * * */ #ifdef HAVE_CONFIG_H # include "config.h" #endif #include #include #include #include #include #include "gstkatetag.h" GST_DEBUG_CATEGORY_EXTERN (gst_katetag_debug); #define GST_CAT_DEFAULT gst_katetag_debug enum { ARG_0, ARG_LANGUAGE, ARG_CATEGORY, ARG_ORIGINAL_CANVAS_WIDTH, ARG_ORIGINAL_CANVAS_HEIGHT, }; static void gst_kate_tag_base_init (gpointer g_class); static void gst_kate_tag_class_init (GstKateTagClass * klass); static void gst_kate_tag_init (GstKateTag * kt, GstKateTagClass * g_class); static GstFlowReturn gst_kate_tag_parse_packet (GstKateParse * parse, GstBuffer * buffer); static void gst_kate_tag_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec); static void gst_kate_tag_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec); static void gst_kate_tag_dispose (GObject * object); #define _do_init(type) \ G_STMT_START{ \ static const GInterfaceInfo tag_setter_info = { \ NULL, \ NULL, \ NULL \ }; \ g_type_add_interface_static (type, GST_TYPE_TAG_SETTER, \ &tag_setter_info); \ }G_STMT_END GST_BOILERPLATE_FULL (GstKateTag, gst_kate_tag, GstKateParse, GST_TYPE_KATE_PARSE, _do_init); static GstElementDetails kate_tag_details = GST_ELEMENT_DETAILS ("Kate stream tagger", "Formatter/Metadata", "Retags kate streams", "Vincent Penquerc'h "); static void gst_kate_tag_base_init (gpointer g_class) { GstElementClass *element_class = GST_ELEMENT_CLASS (g_class); gst_element_class_set_details (element_class, &kate_tag_details); } static void gst_kate_tag_class_init (GstKateTagClass * klass) { GObjectClass *gobject_class; GstKateParseClass *gstkateparse_class; gobject_class = (GObjectClass *) klass; gstkateparse_class = GST_KATE_PARSE_CLASS (klass); gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_kate_tag_set_property); gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_kate_tag_get_property); gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_kate_tag_dispose); g_object_class_install_property (gobject_class, ARG_LANGUAGE, g_param_spec_string ("language", "Language", "Set the language of the stream", "", G_PARAM_READWRITE)); g_object_class_install_property (gobject_class, ARG_CATEGORY, g_param_spec_string ("category", "Category", "Set the category of the stream", "", G_PARAM_READWRITE)); g_object_class_install_property (gobject_class, ARG_ORIGINAL_CANVAS_WIDTH, g_param_spec_int ("original-canvas-width", "Original canvas width", "Set the width of the canvas this stream was authored for (0 is unspecified)", 0, G_MAXINT, 0, G_PARAM_READWRITE)); g_object_class_install_property (gobject_class, ARG_ORIGINAL_CANVAS_HEIGHT, g_param_spec_int ("original-canvas-height", "Original canvas height", "Set the height of the canvas this stream was authored for (0 is unspecified)", 0, G_MAXINT, 0, G_PARAM_READWRITE)); gstkateparse_class->parse_packet = GST_DEBUG_FUNCPTR (gst_kate_tag_parse_packet); } static void gst_kate_tag_init (GstKateTag * kt, GstKateTagClass * g_class) { kt->language = NULL; kt->category = NULL; kt->original_canvas_width = -1; kt->original_canvas_height = -1; } static void gst_kate_tag_dispose (GObject * object) { GstKateTag *kt = GST_KATE_TAG (object); GST_LOG_OBJECT (kt, "disposing"); if (kt->language) { g_free (kt->language); kt->language = NULL; } if (kt->category) { g_free (kt->category); kt->category = NULL; } GST_CALL_PARENT (G_OBJECT_CLASS, dispose, (object)); } static void gst_kate_tag_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec) { GstKateTag *kt = GST_KATE_TAG (object); const char *str; switch (prop_id) { case ARG_LANGUAGE: if (kt->language) { g_free (kt->language); kt->language = NULL; } str = g_value_get_string (value); if (str) kt->language = g_strdup (str); break; case ARG_CATEGORY: if (kt->category) { g_free (kt->category); kt->category = NULL; } str = g_value_get_string (value); if (str) kt->category = g_strdup (str); break; case ARG_ORIGINAL_CANVAS_WIDTH: kt->original_canvas_width = g_value_get_int (value); break; case ARG_ORIGINAL_CANVAS_HEIGHT: kt->original_canvas_height = g_value_get_int (value); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void gst_kate_tag_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec) { GstKateTag *kt = GST_KATE_TAG (object); switch (prop_id) { case ARG_LANGUAGE: g_value_set_string (value, kt->language ? kt->language : ""); break; case ARG_CATEGORY: g_value_set_string (value, kt->category ? kt->category : ""); break; case ARG_ORIGINAL_CANVAS_WIDTH: g_value_set_int (value, kt->original_canvas_width); break; case ARG_ORIGINAL_CANVAS_HEIGHT: g_value_set_int (value, kt->original_canvas_height); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static guint16 encode_canvas_size (size_t size) { size_t base = size; size_t shift = 0; int value; while (base & ~((1 << 12) - 1)) { /* we have a high bit we can't fit, increase shift if we wouldn't lose low bits */ if ((size >> shift) & 1) return 0; ++shift; base >>= 1; } if (G_UNLIKELY (shift >= 16)) return 0; /* the size can be represented in our encoding */ value = (base << 4) | shift; return (guint16) value; } static GstFlowReturn gst_kate_tag_parse_packet (GstKateParse * parse, GstBuffer * buffer) { GstTagList *old_tags, *new_tags; const GstTagList *user_tags; GstKateTag *kt; gchar *encoder = NULL; GstBuffer *new_buf; kt = GST_KATE_TAG (parse); /* rewrite the language and category */ if (GST_BUFFER_SIZE (buffer) >= 64 && GST_BUFFER_DATA (buffer)[0] == 0x80) { GstBuffer *new_buffer = gst_buffer_copy (buffer); gst_buffer_unref (buffer); buffer = new_buffer; /* language is at offset 32, 16 bytes, zero terminated */ if (kt->language) { strncpy ((char *) GST_BUFFER_DATA (buffer) + 32, kt->language, 15); GST_BUFFER_DATA (buffer)[47] = 0; } /* category is at offset 48, 16 bytes, zero terminated */ if (kt->category) { strncpy ((char *) GST_BUFFER_DATA (buffer) + 48, kt->category, 15); GST_BUFFER_DATA (buffer)[63] = 0; } if (kt->original_canvas_width >= 0) { guint16 v = encode_canvas_size (kt->original_canvas_width); GST_BUFFER_DATA (buffer)[16] = v & 0xff; GST_BUFFER_DATA (buffer)[17] = (v >> 8) & 0xff; } if (kt->original_canvas_height >= 0) { guint16 v = encode_canvas_size (kt->original_canvas_height); GST_BUFFER_DATA (buffer)[18] = v & 0xff; GST_BUFFER_DATA (buffer)[19] = (v >> 8) & 0xff; } } /* rewrite the comments packet */ if (GST_BUFFER_SIZE (buffer) >= 9 && GST_BUFFER_DATA (buffer)[0] == 0x81) { old_tags = gst_tag_list_from_vorbiscomment_buffer (buffer, (const guint8 *) "\201kate\0\0\0\0", 9, &encoder); user_tags = gst_tag_setter_get_tag_list (GST_TAG_SETTER (kt)); /* build new tag list */ new_tags = gst_tag_list_merge (user_tags, old_tags, gst_tag_setter_get_tag_merge_mode (GST_TAG_SETTER (kt))); gst_tag_list_free (old_tags); new_buf = gst_tag_list_to_vorbiscomment_buffer (new_tags, (const guint8 *) "\201kate\0\0\0\0", 9, encoder); gst_buffer_copy_metadata (new_buf, buffer, GST_BUFFER_COPY_TIMESTAMPS); gst_tag_list_free (new_tags); g_free (encoder); gst_buffer_unref (buffer); /* the buffer will have the framing bit used by Vorbis, but we don't use it */ --GST_BUFFER_SIZE (new_buf); buffer = new_buf; } return GST_KATE_PARSE_CLASS (parent_class)->parse_packet (parse, buffer); }