ext/kate/gstkatetag.c - imx-gst-plugins-bad - Git at Google

 /*
  * GStreamer
  * Copyright (C) 2006 James Livingston <doclivingston@gmail.com>
  * Copyright (C) 2008 Vincent Penquerc'h <ogg.k.ogg.k@googlemail.com>
  *
  * 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
  *
  * <refsect2>
  * <para>
  * 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.
  * </para>
  * <para>
  * 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.
  * </para>
  * <para>
  * 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).
  * </para>
  * <title>Example pipelines</title>
  * <para>
  * 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:
  * <programlisting>
  * gst-launch -v filesrc location=foo.ogg ! oggdemux ! katetag ! oggmux ! filesink location=bar.ogg
  * </programlisting>
  * </para>
  * <para>
  * This pipeline will set the language and category of the stream to the
  * given values:
  * <programlisting>
  * gst-launch -v filesrc location=foo.ogg ! oggdemux ! katetag language=pt_BR category=subtitles ! oggmux ! filesink location=bar.ogg
  * </programlisting>
  * </para>
  * </refsect2>
  */

 #ifdef HAVE_CONFIG_H
 #  include "config.h"
 #endif

 #include <string.h>
 #include <glib.h>
 #include <gst/tag/tag.h>
 #include <gst/gsttagsetter.h>

 #include <kate/kate.h>

 #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 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 void
 gst_kate_tag_base_init (gpointer g_class)
 {
   GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);

   gst_element_class_set_details_simple (element_class, "Kate stream tagger",
       "Formatter/Metadata",
       "Retags kate streams", "Vincent Penquerc'h <ogg.k.ogg.k@googlemail.com>");
 }

 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);
 }
	/*
	* GStreamer
	* Copyright (C) 2006 James Livingston <doclivingston@gmail.com>
	* Copyright (C) 2008 Vincent Penquerc'h <ogg.k.ogg.k@googlemail.com>
	*
	* 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
	*
	* <refsect2>
	* <para>
	* 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.
	* </para>
	* <para>
	* 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.
	* </para>
	* <para>
	* 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).
	* </para>
	* <title>Example pipelines</title>
	* <para>
	* 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:
	* <programlisting>
	* gst-launch -v filesrc location=foo.ogg ! oggdemux ! katetag ! oggmux ! filesink location=bar.ogg
	* </programlisting>
	* </para>
	* <para>
	* This pipeline will set the language and category of the stream to the
	* given values:
	* <programlisting>
	* gst-launch -v filesrc location=foo.ogg ! oggdemux ! katetag language=pt_BR category=subtitles ! oggmux ! filesink location=bar.ogg
	* </programlisting>
	* </para>
	* </refsect2>
	*/

	#ifdef HAVE_CONFIG_H
	# include "config.h"
	#endif

	#include <string.h>
	#include <glib.h>
	#include <gst/tag/tag.h>
	#include <gst/gsttagsetter.h>

	#include <kate/kate.h>

	#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 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 void
	gst_kate_tag_base_init (gpointer g_class)
	{
	GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);

	gst_element_class_set_details_simple (element_class, "Kate stream tagger",
	"Formatter/Metadata",
	"Retags kate streams", "Vincent Penquerc'h <ogg.k.ogg.k@googlemail.com>");
	}

	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);
	}