gstreamer/ext/annodex/gstcmmldec.c
2011-11-16 17:27:13 +01:00

690 lines
20 KiB
C

/*
* gstcmmldec.c - GStreamer annodex CMML decoder
* Copyright (C) 2005 Alessandro Decina
*
* Authors:
* Alessandro Decina <alessandro@nnva.org>
*
* 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-cmmldec
* @see_also: cmmlenc, oggdemux
*
* Cmmldec extracts a CMML document from a CMML bitstream.<ulink
* url="http://www.annodex.net/TR/draft-pfeiffer-cmml-02.html">CMML</ulink> is
* an XML markup language for time-continuous data maintained by the <ulink
* url="http:/www.annodex.org/">Annodex Foundation</ulink>.
*
* <refsect2>
* <title>Example pipeline</title>
* |[
* gst-launch -v filesrc location=annotated.ogg ! oggdemux ! cmmldec ! filesink location=annotations.cmml
* ]|
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include <glib.h>
#include <gst/tag/tag.h>
#include "gstannodex.h"
#include "gstcmmltag.h"
#include "gstcmmldec.h"
#include "gstcmmlutils.h"
GST_DEBUG_CATEGORY_STATIC (cmmldec);
#define GST_CAT_DEFAULT cmmldec
#define CMML_IDENT_HEADER_SIZE 29
enum
{
ARG_0,
GST_CMML_DEC_WAIT_CLIP_END
};
enum
{
LAST_SIGNAL
};
static GstStaticPadTemplate gst_cmml_dec_src_factory =
GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("text/x-cmml, encoded = (boolean) false")
);
static GstStaticPadTemplate gst_cmml_dec_sink_factory =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("text/x-cmml, encoded = (boolean) true")
);
/* GstCmmlDec */
#define gst_cmml_dec_parent_class parent_class
G_DEFINE_TYPE (GstCmmlDec, gst_cmml_dec, GST_TYPE_ELEMENT);
static void gst_cmml_dec_get_property (GObject * dec, guint property_id,
GValue * value, GParamSpec * pspec);
static void gst_cmml_dec_set_property (GObject * dec, guint property_id,
const GValue * value, GParamSpec * pspec);
static gboolean gst_cmml_dec_sink_query (GstPad * pad, GstObject * parent,
GstQuery * query);
static gboolean gst_cmml_dec_sink_event (GstPad * pad, GstEvent * event);
static gboolean gst_cmml_dec_convert (GstPad * pad, GstFormat src_fmt,
gint64 src_val, GstFormat * dest_fmt, gint64 * dest_val);
static GstStateChangeReturn gst_cmml_dec_change_state (GstElement * element,
GstStateChange transition);
static GstFlowReturn gst_cmml_dec_chain (GstPad * pad, GstBuffer * buffer);
static GstCmmlPacketType gst_cmml_dec_parse_packet_type (GstCmmlDec * dec,
gchar * data, gsize size);
static void gst_cmml_dec_parse_ident_header (GstCmmlDec * dec, guint8 * data,
gsize size);
static void gst_cmml_dec_parse_first_header (GstCmmlDec * dec, guint8 * data,
gsize size);
static void gst_cmml_dec_parse_preamble (GstCmmlDec * dec, guchar * preamble,
guchar * cmml_root_element);
static void gst_cmml_dec_parse_xml (GstCmmlDec * dec, guchar * data,
guint size);
static void gst_cmml_dec_parse_head (GstCmmlDec * dec, GstCmmlTagHead * head);
static void gst_cmml_dec_parse_clip (GstCmmlDec * dec, GstCmmlTagClip * clip);
static GstFlowReturn gst_cmml_dec_new_buffer (GstCmmlDec * dec,
guchar * data, gint size, GstBuffer ** buffer);
static void gst_cmml_dec_push_clip (GstCmmlDec * dec, GstCmmlTagClip * clip);
static void gst_cmml_dec_send_clip_tag (GstCmmlDec * dec,
GstCmmlTagClip * clip);
static void gst_cmml_dec_finalize (GObject * object);
static void
gst_cmml_dec_class_init (GstCmmlDecClass * klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
object_class->set_property = gst_cmml_dec_set_property;
object_class->get_property = gst_cmml_dec_get_property;
object_class->finalize = gst_cmml_dec_finalize;
g_object_class_install_property (object_class, GST_CMML_DEC_WAIT_CLIP_END,
g_param_spec_boolean ("wait-clip-end-time",
"Wait clip end time",
"Send a tag for a clip when the clip ends, setting its end-time. "
"Use when you need to know both clip's start-time and end-time.",
FALSE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
element_class->change_state = gst_cmml_dec_change_state;
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&gst_cmml_dec_sink_factory));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&gst_cmml_dec_src_factory));
gst_element_class_set_details_simple (element_class, "CMML stream decoder",
"Codec/Decoder",
"Decodes CMML streams", "Alessandro Decina <alessandro@nnva.org>");
}
static void
gst_cmml_dec_init (GstCmmlDec * dec)
{
dec->sinkpad =
gst_pad_new_from_static_template (&gst_cmml_dec_sink_factory, "sink");
gst_pad_set_chain_function (dec->sinkpad, gst_cmml_dec_chain);
gst_pad_set_query_function (dec->sinkpad, gst_cmml_dec_sink_query);
gst_pad_set_event_function (dec->sinkpad, gst_cmml_dec_sink_event);
gst_element_add_pad (GST_ELEMENT (dec), dec->sinkpad);
dec->srcpad =
gst_pad_new_from_static_template (&gst_cmml_dec_src_factory, "src");
gst_element_add_pad (GST_ELEMENT (dec), dec->srcpad);
dec->wait_clip_end = FALSE;
}
static void
gst_cmml_dec_get_property (GObject * object, guint property_id,
GValue * value, GParamSpec * pspec)
{
GstCmmlDec *dec = GST_CMML_DEC (object);
switch (property_id) {
case GST_CMML_DEC_WAIT_CLIP_END:
g_value_set_boolean (value, dec->wait_clip_end);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}
}
static void
gst_cmml_dec_set_property (GObject * object, guint property_id,
const GValue * value, GParamSpec * pspec)
{
GstCmmlDec *dec = GST_CMML_DEC (object);
switch (property_id) {
case GST_CMML_DEC_WAIT_CLIP_END:
dec->wait_clip_end = g_value_get_boolean (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (dec, property_id, pspec);
}
}
static void
gst_cmml_dec_finalize (GObject * object)
{
GstCmmlDec *dec = GST_CMML_DEC (object);
if (dec->tracks) {
gst_cmml_track_list_destroy (dec->tracks);
dec->tracks = NULL;
}
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static GstStateChangeReturn
gst_cmml_dec_change_state (GstElement * element, GstStateChange transition)
{
GstCmmlDec *dec = GST_CMML_DEC (element);
GstStateChangeReturn res;
switch (transition) {
case GST_STATE_CHANGE_READY_TO_PAUSED:
dec->parser = gst_cmml_parser_new (GST_CMML_PARSER_DECODE);
dec->parser->user_data = dec;
dec->parser->preamble_callback =
(GstCmmlParserPreambleCallback) gst_cmml_dec_parse_preamble;
dec->parser->head_callback =
(GstCmmlParserHeadCallback) gst_cmml_dec_parse_head;
dec->parser->clip_callback =
(GstCmmlParserClipCallback) gst_cmml_dec_parse_clip;
dec->major = -1;
dec->minor = -1;
dec->granulerate_n = -1;
dec->granulerate_d = -1;
dec->granuleshift = 0;
dec->granulepos = 0;
dec->flow_return = GST_FLOW_OK;
dec->sent_root = FALSE;
dec->tracks = gst_cmml_track_list_new ();
break;
default:
break;
}
res = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
switch (transition) {
case GST_STATE_CHANGE_PAUSED_TO_READY:
gst_cmml_parser_free (dec->parser);
gst_cmml_track_list_destroy (dec->tracks);
dec->tracks = NULL;
break;
default:
break;
}
return res;
}
static gboolean
gst_cmml_dec_sink_query (GstPad * pad, GstObject * parent, GstQuery * query)
{
gboolean res = FALSE;
switch (GST_QUERY_TYPE (query)) {
case GST_QUERY_CONVERT:
{
GstFormat src_fmt, dest_fmt;
gint64 src_val, dest_val;
gst_query_parse_convert (query, &src_fmt, &src_val, &dest_fmt, &dest_val);
res = gst_cmml_dec_convert (pad, src_fmt, src_val, &dest_fmt, &dest_val);
if (res)
gst_query_set_convert (query, src_fmt, src_val, dest_fmt, dest_val);
break;
}
default:
break;
}
return res;
}
static gboolean
gst_cmml_dec_convert (GstPad * pad,
GstFormat src_fmt, gint64 src_val, GstFormat * dest_fmt, gint64 * dest_val)
{
GstCmmlDec *dec = GST_CMML_DEC (GST_PAD_PARENT (pad));
gboolean res = FALSE;
switch (src_fmt) {
case GST_FORMAT_DEFAULT:
switch (*dest_fmt) {
case GST_FORMAT_TIME:
{
*dest_val = gst_annodex_granule_to_time (src_val, dec->granulerate_n,
dec->granulerate_d, dec->granuleshift);
res = TRUE;
break;
}
default:
break;
}
break;
default:
break;
}
return res;
}
static gboolean
gst_cmml_dec_sink_event (GstPad * pad, GstEvent * event)
{
GstCmmlDec *dec = GST_CMML_DEC (GST_PAD_PARENT (pad));
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_EOS:
{
GstBuffer *buffer;
GstCmmlTagClip *clip;
GList *clips, *walk;
GST_INFO_OBJECT (dec, "got EOS, flushing clips");
/* since we output a clip when the next one in the same track is found, on
* EOS we need to output the last clip (if any) of every track
*/
clips = gst_cmml_track_list_get_clips (dec->tracks);
for (walk = clips; walk; walk = g_list_next (walk)) {
clip = GST_CMML_TAG_CLIP (walk->data);
gst_cmml_dec_push_clip (dec, clip);
if (dec->wait_clip_end) {
clip->end_time = dec->timestamp;
gst_cmml_dec_send_clip_tag (dec, clip);
}
}
g_list_free (clips);
/* send the cmml end tag */
dec->flow_return = gst_cmml_dec_new_buffer (dec,
(guchar *) "</cmml>", strlen ("</cmml>"), &buffer);
if (dec->flow_return == GST_FLOW_OK)
dec->flow_return = gst_pad_push (dec->srcpad, buffer);
if (dec->flow_return == GST_FLOW_NOT_LINKED)
dec->flow_return = GST_FLOW_OK; /* Ignore NOT_LINKED */
break;
}
default:
break;
}
return gst_pad_event_default (pad, event);
}
static GstFlowReturn
gst_cmml_dec_chain (GstPad * pad, GstBuffer * buffer)
{
GstCmmlDec *dec = GST_CMML_DEC (GST_PAD_PARENT (pad));
GstCmmlPacketType packet;
guint8 *data;
gsize size;
data = gst_buffer_map (buffer, &size, NULL, GST_MAP_READ);
if (size == 0) {
/* the EOS page could be empty */
dec->flow_return = GST_FLOW_OK;
goto done;
}
dec->granulepos = GST_BUFFER_OFFSET_END (buffer);
dec->timestamp = gst_annodex_granule_to_time (dec->granulepos,
dec->granulerate_n, dec->granulerate_d, dec->granuleshift);
/* identify the packet type */
packet = gst_cmml_dec_parse_packet_type (dec, (gchar *) data, size);
/* handle the packet. the handler will set dec->flow_return */
switch (packet) {
case GST_CMML_PACKET_IDENT_HEADER:
if (dec->sent_root == FALSE)
/* don't parse the ident again in case of seeking to the beginning */
gst_cmml_dec_parse_ident_header (dec, data, size);
break;
case GST_CMML_PACKET_FIRST_HEADER:
if (dec->sent_root == FALSE)
/* don't parse the xml preamble if it has already been parsed because it
* would error out, so seeking to the beginning would fail */
gst_cmml_dec_parse_first_header (dec, data, size);
break;
case GST_CMML_PACKET_SECOND_HEADER:
case GST_CMML_PACKET_CLIP:
gst_cmml_dec_parse_xml (dec, data, size);
break;
case GST_CMML_PACKET_UNKNOWN:
default:
GST_ELEMENT_ERROR (dec, STREAM, DECODE, (NULL), ("unknown packet type"));
dec->flow_return = GST_FLOW_ERROR;
}
done:
gst_buffer_unmap (buffer, data, size);
gst_buffer_unref (buffer);
return dec->flow_return;
}
/* finds the packet type of the buffer
*/
static GstCmmlPacketType
gst_cmml_dec_parse_packet_type (GstCmmlDec * dec, gchar * data, gsize size)
{
GstCmmlPacketType packet_type = GST_CMML_PACKET_UNKNOWN;
if (size >= 8 && !memcmp (data, "CMML\0\0\0\0", 8)) {
packet_type = GST_CMML_PACKET_IDENT_HEADER;
} else if (size >= 5) {
if (!strncmp (data, "<?xml", 5))
packet_type = GST_CMML_PACKET_FIRST_HEADER;
else if (!strncmp (data, "<head", 5))
packet_type = GST_CMML_PACKET_SECOND_HEADER;
else if (!strncmp (data, "<clip", 5))
packet_type = GST_CMML_PACKET_CLIP;
}
return packet_type;
}
/* creates a new buffer and sets caps and timestamp on it
*/
static GstFlowReturn
gst_cmml_dec_new_buffer (GstCmmlDec * dec,
guchar * data, gint size, GstBuffer ** buffer)
{
GstFlowReturn res;
*buffer = gst_buffer_new_allocate (NULL, size, 0);
if (*buffer != NULL) {
if (data)
gst_buffer_fill (*buffer, 0, data, size);
GST_BUFFER_TIMESTAMP (*buffer) = dec->timestamp;
res = GST_FLOW_OK;
} else {
GST_WARNING_OBJECT (dec, "could not allocate buffer");
res = GST_FLOW_ERROR;
}
return res;
}
/* parses the first CMML packet (the ident header)
*/
static void
gst_cmml_dec_parse_ident_header (GstCmmlDec * dec, guint8 * data, gsize size)
{
/* the ident header has a fixed length */
if (size != CMML_IDENT_HEADER_SIZE) {
GST_ELEMENT_ERROR (dec, STREAM, DECODE,
(NULL), ("wrong ident header size: %d", size));
dec->flow_return = GST_FLOW_ERROR;
return;
}
data += 8;
dec->major = GST_READ_UINT16_LE (data);
data += 2;
dec->minor = GST_READ_UINT16_LE (data);
data += 2;
dec->granulerate_n = GST_READ_UINT64_LE (data);
data += 8;
dec->granulerate_d = GST_READ_UINT64_LE (data);
data += 8;
dec->granuleshift = GST_READ_UINT8 (data);
GST_INFO_OBJECT (dec, "bitstream initialized "
"(major: %" G_GINT16_FORMAT " minor: %" G_GINT16_FORMAT
" granulerate_n: %" G_GINT64_FORMAT " granulerate_d: %" G_GINT64_FORMAT
" granuleshift: %d)",
dec->major, dec->minor,
dec->granulerate_n, dec->granulerate_d, dec->granuleshift);
dec->flow_return = GST_FLOW_OK;
}
/* parses the first secondary header.
* the first secondary header contains the xml version, the doctype and the
* optional "cmml" processing instruction.
*/
static void
gst_cmml_dec_parse_first_header (GstCmmlDec * dec, guint8 * data, gsize size)
{
gst_cmml_dec_parse_xml (dec, data, size);
/* if there is a processing instruction, gst_cmml_dec_parse_preamble
* will be triggered. Otherwise we need to call it manually.
*/
if (dec->flow_return == GST_FLOW_OK && !dec->sent_root) {
guchar *preamble = (guchar *) g_strndup ((gchar *) data, size);
gst_cmml_dec_parse_preamble (dec, preamble, (guchar *) "<cmml>");
g_free (preamble);
}
}
/* feeds data into the cmml parser.
*/
static void
gst_cmml_dec_parse_xml (GstCmmlDec * dec, guchar * data, guint size)
{
GError *err = NULL;
if (!gst_cmml_parser_parse_chunk (dec->parser, (gchar *) data, size, &err)) {
GST_ELEMENT_ERROR (dec, STREAM, DECODE, (NULL), ("%s", err->message));
g_error_free (err);
dec->flow_return = GST_FLOW_ERROR;
}
}
static void
gst_cmml_dec_parse_preamble (GstCmmlDec * dec, guchar * preamble,
guchar * root_element)
{
GstBuffer *buffer;
guchar *encoded_preamble;
encoded_preamble = (guchar *) g_strconcat ((gchar *) preamble,
(gchar *) root_element, NULL);
/* send the root element to the internal parser */
gst_cmml_dec_parse_xml (dec, root_element, strlen ((gchar *) root_element));
dec->sent_root = TRUE;
/* push the root element */
dec->flow_return = gst_cmml_dec_new_buffer (dec,
encoded_preamble, strlen ((gchar *) encoded_preamble), &buffer);
if (dec->flow_return == GST_FLOW_OK) {
dec->flow_return = gst_pad_push (dec->srcpad, buffer);
}
if (dec->flow_return == GST_FLOW_OK) {
GST_INFO_OBJECT (dec, "preamble parsed");
}
g_free (encoded_preamble);
return;
}
/* outputs the cmml head element and send TITLE and CMML_HEAD tags.
* This callback is registered with dec->parser. It is called when the
* head element is parsed.
*/
static void
gst_cmml_dec_parse_head (GstCmmlDec * dec, GstCmmlTagHead * head)
{
GstTagList *tags;
GValue str_val = { 0 }, title_val = {
0};
guchar *head_str;
GstBuffer *buffer;
GST_DEBUG_OBJECT (dec, "found CMML head (title: %s base: %s)",
head->title, head->base);
/* FIXME: what's the point of all this GValue transform crack? */
/* create the GST_TAG_TITLE tag */
g_value_init (&str_val, G_TYPE_STRING);
g_value_init (&title_val, gst_tag_get_type (GST_TAG_TITLE));
g_value_set_string (&str_val, (gchar *) head->title);
g_value_transform (&str_val, &title_val);
tags = gst_tag_list_new_empty ();
gst_tag_list_add_values (tags, GST_TAG_MERGE_APPEND,
GST_TAG_TITLE, &title_val, NULL);
gst_tag_list_add (tags, GST_TAG_MERGE_APPEND, GST_TAG_CMML_HEAD, head, NULL);
gst_pad_push_event (dec->srcpad, gst_event_new_tag (tags));
g_value_unset (&str_val);
g_value_unset (&title_val);
head_str = gst_cmml_parser_tag_head_to_string (dec->parser, head);
dec->flow_return = gst_cmml_dec_new_buffer (dec,
head_str, strlen ((gchar *) head_str), &buffer);
g_free (head_str);
if (dec->flow_return == GST_FLOW_OK)
dec->flow_return = gst_pad_push (dec->srcpad, buffer);
if (dec->flow_return == GST_FLOW_NOT_LINKED)
dec->flow_return = GST_FLOW_OK; /* Ignore NOT_LINKED */
}
/* send a TAG_MESSAGE event for a clip */
static void
gst_cmml_dec_send_clip_tag (GstCmmlDec * dec, GstCmmlTagClip * clip)
{
GstTagList *tags;
GST_DEBUG_OBJECT (dec, "sending clip tag %s", clip->id);
tags = gst_tag_list_new (GST_TAG_CMML_CLIP, clip, NULL);
gst_pad_push_event (dec->srcpad, gst_event_new_tag (tags));
}
/* push the string representation of a clip */
static void
gst_cmml_dec_push_clip (GstCmmlDec * dec, GstCmmlTagClip * clip)
{
GstBuffer *buffer;
guchar *clip_str;
GST_DEBUG_OBJECT (dec, "pushing clip %s", clip->id);
clip_str = gst_cmml_parser_tag_clip_to_string (dec->parser, clip);
dec->flow_return = gst_cmml_dec_new_buffer (dec,
clip_str, strlen ((gchar *) clip_str), &buffer);
if (dec->flow_return == GST_FLOW_OK)
dec->flow_return = gst_pad_push (dec->srcpad, buffer);
if (dec->flow_return == GST_FLOW_NOT_LINKED)
dec->flow_return = GST_FLOW_OK; /* Ignore NOT_LINKED */
g_free (clip_str);
}
/* decode a clip tag
* this callback is registered with dec->parser. It is called whenever a
* clip is parsed.
*/
static void
gst_cmml_dec_parse_clip (GstCmmlDec * dec, GstCmmlTagClip * clip)
{
GstCmmlTagClip *prev_clip;
dec->flow_return = GST_FLOW_OK;
if (clip->empty)
GST_INFO_OBJECT (dec, "parsing empty clip");
else
GST_INFO_OBJECT (dec, "parsing clip (id: %s)", clip->id);
clip->start_time = dec->timestamp;
if (clip->start_time == GST_CLOCK_TIME_NONE) {
GST_ELEMENT_ERROR (dec, STREAM, DECODE,
(NULL), ("invalid clip start time"));
dec->flow_return = GST_FLOW_ERROR;
return;
}
/* get the last clip in the current track */
prev_clip = gst_cmml_track_list_get_track_last_clip (dec->tracks,
(gchar *) clip->track);
if (prev_clip) {
/* output the previous clip */
if (clip->empty)
/* the current clip marks the end of the previous one */
prev_clip->end_time = clip->start_time;
gst_cmml_dec_push_clip (dec, prev_clip);
}
if (dec->wait_clip_end) {
/* now it's time to send the tag for the previous clip */
if (prev_clip) {
prev_clip->end_time = clip->start_time;
gst_cmml_dec_send_clip_tag (dec, prev_clip);
}
} else if (!clip->empty) {
/* send the tag for the current clip */
gst_cmml_dec_send_clip_tag (dec, clip);
}
if (prev_clip)
gst_cmml_track_list_del_clip (dec->tracks, prev_clip);
if (!clip->empty)
if (!gst_cmml_track_list_has_clip (dec->tracks, clip))
gst_cmml_track_list_add_clip (dec->tracks, clip);
}
gboolean
gst_cmml_dec_plugin_init (GstPlugin * plugin)
{
if (!gst_element_register (plugin, "cmmldec", GST_RANK_PRIMARY,
GST_TYPE_CMML_DEC))
return FALSE;
GST_DEBUG_CATEGORY_INIT (cmmldec, "cmmldec", 0,
"annodex CMML decoding element");
return TRUE;
}