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/*
* 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., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, 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 gst_kate_tag_parent_class parent_class
G_DEFINE_TYPE_WITH_CODE (GstKateTag, gst_kate_tag, GST_TYPE_KATE_PARSE,
G_IMPLEMENT_INTERFACE (GST_TYPE_TAG_SETTER, NULL));
static void
gst_kate_tag_class_init (GstKateTagClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
GstKateParseClass *gstkateparse_class;
gobject_class = (GObjectClass *) klass;
gstelement_class = (GstElementClass *) 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_PARAM_STATIC_STRINGS));
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_PARAM_STATIC_STRINGS));
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_PARAM_STATIC_STRINGS));
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 | G_PARAM_STATIC_STRINGS));
gst_element_class_set_static_metadata (gstelement_class, "Kate stream tagger",
"Formatter/Metadata",
"Retags kate streams", "Vincent Penquerc'h <ogg.k.ogg.k@googlemail.com>");
gstkateparse_class->parse_packet =
GST_DEBUG_FUNCPTR (gst_kate_tag_parse_packet);
}
static void
gst_kate_tag_init (GstKateTag * kt)
{
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;
GstMapInfo info;
kt = GST_KATE_TAG (parse);
if (!gst_buffer_map (buffer, &info, GST_MAP_READ)) {
GST_ERROR_OBJECT (parse, "Failed to map buffer");
return GST_FLOW_ERROR;
}
/* rewrite the language and category */
if (info.size >= 64 && info.data[0] == 0x80) {
GstBuffer *new_buffer;
gst_buffer_unmap (buffer, &info);
new_buffer = gst_buffer_copy (buffer);
gst_buffer_unref (buffer);
buffer = new_buffer;
if (!gst_buffer_map (buffer, &info, GST_MAP_READWRITE)) {
GST_ERROR_OBJECT (parse, "Failed to map copied buffer READWRITE");
return GST_FLOW_ERROR;
}
/* language is at offset 32, 16 bytes, zero terminated */
if (kt->language) {
strncpy ((char *) info.data + 32, kt->language, 15);
info.data[47] = 0;
}
/* category is at offset 48, 16 bytes, zero terminated */
if (kt->category) {
strncpy ((char *) info.data + 48, kt->category, 15);
info.data[63] = 0;
}
if (kt->original_canvas_width >= 0) {
guint16 v = encode_canvas_size (kt->original_canvas_width);
info.data[16] = v & 0xff;
info.data[17] = (v >> 8) & 0xff;
}
if (kt->original_canvas_height >= 0) {
guint16 v = encode_canvas_size (kt->original_canvas_height);
info.data[18] = v & 0xff;
info.data[19] = (v >> 8) & 0xff;
}
}
/* rewrite the comments packet */
if (info.size >= 9 && info.data[0] == 0x81) {
old_tags =
gst_tag_list_from_vorbiscomment (info.data, info.size,
(const guint8 *) "\201kate\0\0\0\0", 9, &encoder);
user_tags = gst_tag_setter_get_tag_list (GST_TAG_SETTER (kt));
gst_buffer_unmap (buffer, &info);
/* 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_unref (old_tags);
new_buf =
gst_tag_list_to_vorbiscomment_buffer (new_tags,
(const guint8 *) "\201kate\0\0\0\0", 9, encoder);
gst_buffer_copy_into (new_buf, buffer, GST_BUFFER_COPY_TIMESTAMPS, 0, -1);
gst_tag_list_unref (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_resize (new_buf, 0, gst_buffer_get_size (new_buf) - 1);
buffer = new_buf;
} else {
gst_buffer_unmap (buffer, &info);
}
return GST_KATE_PARSE_CLASS (parent_class)->parse_packet (parse, buffer);
}