gstreamer/gst/jpegformat/gstjifmux.c
2011-04-11 18:29:28 +03:00

783 lines
22 KiB
C

/* GStreamer
*
* jifmux: JPEG interchange format muxer
*
* Copyright (C) 2010 Stefan Kost <stefan.kost@nokia.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser 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-jifmux
* @short_description: JPEG interchange format writer
*
* Writes a JPEG image as JPEG/EXIF or JPEG/JFIF including various metadata. The
* jpeg image received on the sink pad should be minimal (e.g. should not
* contain metadata already).
*
* <refsect2>
* <title>Example launch line</title>
* |[
* gst-launch -v videotestsrc num-buffers=1 ! jpegenc ! jifmux ! filesink location=...
* ]|
* The above pipeline renders a frame, encodes to jpeg, adds metadata and writes
* it to disk.
* </refsect2>
*/
/*
jpeg interchange format:
file header : SOI, APPn{JFIF,EXIF,...}
frame header: DQT, SOF
scan header : {DAC,DHT},DRI,SOS
<scan data>
file trailer: EOI
tests:
gst-launch videotestsrc num-buffers=1 ! jpegenc ! jifmux ! filesink location=test1.jpeg
gst-launch videotestsrc num-buffers=1 ! jpegenc ! taginject tags="comment=\"test image\"" ! jifmux ! filesink location=test2.jpeg
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <string.h>
#include <gst/base/gstbytereader.h>
#include <gst/base/gstbytewriter.h>
#include <gst/tag/tag.h>
#include <gst/tag/xmpwriter.h>
#include "gstjifmux.h"
static GstStaticPadTemplate gst_jif_mux_src_pad_template =
GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("image/jpeg")
);
static GstStaticPadTemplate gst_jif_mux_sink_pad_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("image/jpeg")
);
GST_DEBUG_CATEGORY_STATIC (jif_mux_debug);
#define GST_CAT_DEFAULT jif_mux_debug
#define COLORSPACE_UNKNOWN (0 << 0)
#define COLORSPACE_GRAYSCALE (1 << 0)
#define COLORSPACE_YUV (1 << 1)
#define COLORSPACE_RGB (1 << 2)
#define COLORSPACE_CMYK (1 << 3)
#define COLORSPACE_YCCK (1 << 4)
typedef struct _GstJifMuxMarker
{
guint8 marker;
guint16 size;
const guint8 *data;
gboolean owned;
} GstJifMuxMarker;
struct _GstJifMuxPrivate
{
GstPad *srcpad;
/* list of GstJifMuxMarker */
GList *markers;
guint scan_size;
const guint8 *scan_data;
};
static void gst_jif_mux_finalize (GObject * object);
static void gst_jif_mux_reset (GstJifMux * self);
static gboolean gst_jif_mux_sink_setcaps (GstPad * pad, GstCaps * caps);
static gboolean gst_jif_mux_sink_event (GstPad * pad, GstEvent * event);
static GstFlowReturn gst_jif_mux_chain (GstPad * pad, GstBuffer * buffer);
static GstStateChangeReturn gst_jif_mux_change_state (GstElement * element,
GstStateChange transition);
static void
gst_jif_type_init (GType type)
{
static const GInterfaceInfo tag_setter_info = { NULL, NULL, NULL };
static const GInterfaceInfo tag_xmp_writer_info = { NULL, NULL, NULL };
g_type_add_interface_static (type, GST_TYPE_TAG_SETTER, &tag_setter_info);
g_type_add_interface_static (type, GST_TYPE_TAG_XMP_WRITER,
&tag_xmp_writer_info);
GST_DEBUG_CATEGORY_INIT (jif_mux_debug, "jifmux", 0,
"JPEG interchange format muxer");
}
GST_BOILERPLATE_FULL (GstJifMux, gst_jif_mux, GstElement, GST_TYPE_ELEMENT,
gst_jif_type_init);
static void
gst_jif_mux_base_init (gpointer g_class)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&gst_jif_mux_src_pad_template));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&gst_jif_mux_sink_pad_template));
gst_element_class_set_details_simple (element_class,
"JPEG stream muxer",
"Video/Muxer",
"Remuxes JPEG images with markers and tags",
"Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>");
}
static void
gst_jif_mux_class_init (GstJifMuxClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
gobject_class = (GObjectClass *) klass;
gstelement_class = (GstElementClass *) klass;
g_type_class_add_private (gobject_class, sizeof (GstJifMuxPrivate));
gstelement_class->change_state = GST_DEBUG_FUNCPTR (gst_jif_mux_change_state);
gobject_class->finalize = gst_jif_mux_finalize;
}
static void
gst_jif_mux_init (GstJifMux * self, GstJifMuxClass * g_class)
{
GstPad *sinkpad;
self->priv = G_TYPE_INSTANCE_GET_PRIVATE (self, GST_TYPE_JIF_MUX,
GstJifMuxPrivate);
/* create the sink and src pads */
sinkpad = gst_pad_new_from_static_template (&gst_jif_mux_sink_pad_template,
"sink");
gst_pad_set_chain_function (sinkpad, GST_DEBUG_FUNCPTR (gst_jif_mux_chain));
gst_pad_set_setcaps_function (sinkpad,
GST_DEBUG_FUNCPTR (gst_jif_mux_sink_setcaps));
gst_pad_set_event_function (sinkpad,
GST_DEBUG_FUNCPTR (gst_jif_mux_sink_event));
gst_element_add_pad (GST_ELEMENT (self), sinkpad);
self->priv->srcpad =
gst_pad_new_from_static_template (&gst_jif_mux_src_pad_template, "src");
gst_element_add_pad (GST_ELEMENT (self), self->priv->srcpad);
}
static void
gst_jif_mux_finalize (GObject * object)
{
GstJifMux *self = GST_JIF_MUX (object);
gst_jif_mux_reset (self);
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static gboolean
gst_jif_mux_sink_setcaps (GstPad * pad, GstCaps * caps)
{
GstJifMux *self = GST_JIF_MUX_CAST (GST_PAD_PARENT (pad));
GstStructure *s = gst_caps_get_structure (caps, 0);
const gchar *variant;
/* should be {combined (default), EXIF, JFIF} */
if ((variant = gst_structure_get_string (s, "variant")) != NULL) {
GST_INFO_OBJECT (pad, "muxing to '%s'", variant);
/* FIXME: do we want to switch it like this or use a gobject property ? */
}
return gst_pad_set_caps (self->priv->srcpad, caps);
}
static gboolean
gst_jif_mux_sink_event (GstPad * pad, GstEvent * event)
{
GstJifMux *self = GST_JIF_MUX (GST_PAD_PARENT (pad));
gboolean ret;
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_TAG:{
GstTagList *list;
GstTagSetter *setter = GST_TAG_SETTER (self);
const GstTagMergeMode mode = gst_tag_setter_get_tag_merge_mode (setter);
gst_event_parse_tag (event, &list);
gst_tag_setter_merge_tags (setter, list, mode);
break;
}
default:
break;
}
ret = gst_pad_event_default (pad, event);
return ret;
}
static void
gst_jif_mux_marker_free (GstJifMuxMarker * m)
{
if (m->owned)
g_free ((gpointer) m->data);
g_slice_free (GstJifMuxMarker, m);
}
static void
gst_jif_mux_reset (GstJifMux * self)
{
GList *node;
GstJifMuxMarker *m;
for (node = self->priv->markers; node; node = g_list_next (node)) {
m = (GstJifMuxMarker *) node->data;
gst_jif_mux_marker_free (m);
}
g_list_free (self->priv->markers);
self->priv->markers = NULL;
}
static GstJifMuxMarker *
gst_jif_mux_new_marker (guint8 marker, guint16 size, const guint8 * data,
gboolean owned)
{
GstJifMuxMarker *m = g_slice_new (GstJifMuxMarker);
m->marker = marker;
m->size = size;
m->data = data;
m->owned = owned;
return m;
}
static gboolean
gst_jif_mux_parse_image (GstJifMux * self, GstBuffer * buf)
{
GstByteReader reader = GST_BYTE_READER_INIT_FROM_BUFFER (buf);
GstJifMuxMarker *m;
guint8 marker = 0;
guint16 size = 0;
const guint8 *data = NULL;
GST_LOG_OBJECT (self, "Received buffer of size: %u", GST_BUFFER_SIZE (buf));
if (!gst_byte_reader_peek_uint8 (&reader, &marker))
goto error;
while (marker == 0xff) {
if (!gst_byte_reader_skip (&reader, 1))
goto error;
if (!gst_byte_reader_get_uint8 (&reader, &marker))
goto error;
switch (marker) {
case RST0:
case RST1:
case RST2:
case RST3:
case RST4:
case RST5:
case RST6:
case RST7:
case SOI:
GST_DEBUG_OBJECT (self, "marker = %x", marker);
m = gst_jif_mux_new_marker (marker, 0, NULL, FALSE);
self->priv->markers = g_list_prepend (self->priv->markers, m);
break;
case EOI:
GST_DEBUG_OBJECT (self, "marker = %x", marker);
m = gst_jif_mux_new_marker (marker, 0, NULL, FALSE);
self->priv->markers = g_list_prepend (self->priv->markers, m);
goto done;
break;
default:
if (!gst_byte_reader_get_uint16_be (&reader, &size))
goto error;
if (!gst_byte_reader_get_data (&reader, size - 2, &data))
goto error;
m = gst_jif_mux_new_marker (marker, size - 2, data, FALSE);
self->priv->markers = g_list_prepend (self->priv->markers, m);
GST_DEBUG_OBJECT (self, "marker = %2x, size = %u", marker, size);
break;
}
if (marker == SOS) {
gint eoi_pos = -1;
gint i;
/* search the last 5 bytes for the EOI marker */
g_assert (GST_BUFFER_SIZE (buf) >= 5);
for (i = 5; i >= 2; i--) {
if (GST_BUFFER_DATA (buf)[GST_BUFFER_SIZE (buf) - i] == 0xFF &&
GST_BUFFER_DATA (buf)[GST_BUFFER_SIZE (buf) - i + 1] == EOI) {
eoi_pos = GST_BUFFER_SIZE (buf) - i;
break;
}
}
if (eoi_pos == -1) {
GST_WARNING_OBJECT (self, "Couldn't find an EOI marker");
eoi_pos = GST_BUFFER_SIZE (buf);
}
/* remaining size except EOI is scan data */
self->priv->scan_size = eoi_pos - gst_byte_reader_get_pos (&reader);
if (!gst_byte_reader_get_data (&reader, self->priv->scan_size,
&self->priv->scan_data))
goto error;
GST_DEBUG_OBJECT (self, "scan data, size = %u", self->priv->scan_size);
}
if (!gst_byte_reader_peek_uint8 (&reader, &marker))
goto error;
}
GST_INFO_OBJECT (self, "done parsing at 0x%x / 0x%x",
gst_byte_reader_get_pos (&reader), GST_BUFFER_SIZE (buf));
done:
self->priv->markers = g_list_reverse (self->priv->markers);
return TRUE;
error:
GST_WARNING_OBJECT (self,
"Error parsing image header (need more that %u bytes available)",
gst_byte_reader_get_remaining (&reader));
return FALSE;
}
static gboolean
gst_jif_mux_mangle_markers (GstJifMux * self)
{
gboolean modified = FALSE;
GstTagList *tags = NULL;
gboolean cleanup_tags;
GstJifMuxMarker *m;
GList *node, *file_hdr = NULL, *frame_hdr = NULL, *scan_hdr = NULL;
GList *app0_jfif = NULL, *app1_exif = NULL, *app1_xmp = NULL, *com = NULL;
GstBuffer *xmp_data;
gchar *str = NULL;
gint colorspace = COLORSPACE_UNKNOWN;
/* update the APP markers
* - put any JFIF APP0 first
* - the Exif APP1 next,
* - the XMP APP1 next,
* - the PSIR APP13 next,
* - followed by all other marker segments
*/
/* find some reference points where we insert before/after */
file_hdr = self->priv->markers;
for (node = self->priv->markers; node; node = g_list_next (node)) {
m = (GstJifMuxMarker *) node->data;
switch (m->marker) {
case APP0:
if (m->size > 5 && !memcmp (m->data, "JFIF\0", 5)) {
GST_DEBUG_OBJECT (self, "found APP0 JFIF");
colorspace |= COLORSPACE_GRAYSCALE | COLORSPACE_YUV;
if (!app0_jfif)
app0_jfif = node;
}
break;
case APP1:
if (m->size > 6 && (!memcmp (m->data, "EXIF\0\0", 6) ||
!memcmp (m->data, "Exif\0\0", 6))) {
GST_DEBUG_OBJECT (self, "found APP1 EXIF");
if (!app1_exif)
app1_exif = node;
} else if (m->size > 29
&& !memcmp (m->data, "http://ns.adobe.com/xap/1.0/\0", 29)) {
GST_INFO_OBJECT (self, "found APP1 XMP, will be replaced");
if (!app1_xmp)
app1_xmp = node;
}
break;
case APP14:
/* check if this contains RGB */
/*
* This marker should have:
* - 'Adobe\0'
* - 2 bytes DCTEncodeVersion
* - 2 bytes flags0
* - 2 bytes flags1
* - 1 byte ColorTransform
* - 0 means unknown (RGB or CMYK)
* - 1 YCbCr
* - 2 YCCK
*/
if ((m->size >= 14)
&& (strncmp ((gchar *) m->data, "Adobe\0", 6) == 0)) {
switch (m->data[11]) {
case 0:
colorspace |= COLORSPACE_RGB | COLORSPACE_CMYK;
break;
case 1:
colorspace |= COLORSPACE_YUV;
break;
case 2:
colorspace |= COLORSPACE_YCCK;
break;
default:
break;
}
}
break;
case COM:
GST_INFO_OBJECT (self, "found COM, will be replaced");
if (!com)
com = node;
break;
case DQT:
case SOF0:
case SOF1:
case SOF2:
case SOF3:
case SOF5:
case SOF6:
case SOF7:
case SOF9:
case SOF10:
case SOF11:
case SOF13:
case SOF14:
case SOF15:
if (!frame_hdr)
frame_hdr = node;
break;
case DAC:
case DHT:
case DRI:
case SOS:
if (!scan_hdr)
scan_hdr = node;
break;
}
}
/* if we want combined or JFIF */
/* check if we don't have JFIF APP0 */
if (!app0_jfif && (colorspace & (COLORSPACE_GRAYSCALE | COLORSPACE_YUV))) {
/* build jfif header */
static const struct
{
gchar id[5];
guint8 ver[2];
guint8 du;
guint8 xd[2], yd[2];
guint8 tw, th;
} jfif_data = {
"JFIF", {
1, 2}, 0, {
0, 1}, /* FIXME: check pixel-aspect from caps */
{
0, 1}, 0, 0};
m = gst_jif_mux_new_marker (APP0, sizeof (jfif_data),
(const guint8 *) &jfif_data, FALSE);
/* insert into self->markers list */
self->priv->markers = g_list_insert (self->priv->markers, m, 1);
app0_jfif = g_list_nth (self->priv->markers, 1);
}
/* else */
/* remove JFIF if exists */
/* Existing exif tags will be removed and our own will be added */
if (!tags) {
tags = (GstTagList *) gst_tag_setter_get_tag_list (GST_TAG_SETTER (self));
cleanup_tags = FALSE;
}
if (!tags) {
tags = gst_tag_list_new ();
cleanup_tags = TRUE;
}
GST_DEBUG_OBJECT (self, "Tags to be serialized %" GST_PTR_FORMAT, tags);
/* FIXME: not happy with those
* - else where we would use VIDEO_CODEC = "Jpeg"
gst_tag_list_add (tags, GST_TAG_MERGE_REPLACE,
GST_TAG_VIDEO_CODEC, "image/jpeg", NULL);
*/
/* Add EXIF */
{
GstBuffer *exif_data;
guint8 *data;
GstJifMuxMarker *m;
GList *pos;
/* insert into self->markers list */
exif_data = gst_tag_list_to_exif_buffer_with_tiff_header (tags);
if (exif_data &&
GST_BUFFER_SIZE (exif_data) + 8 >= G_GUINT64_CONSTANT (65536)) {
GST_WARNING_OBJECT (self, "Exif tags data size exceed maximum size");
gst_buffer_unref (exif_data);
exif_data = NULL;
}
if (exif_data) {
data = g_malloc0 (GST_BUFFER_SIZE (exif_data) + 6);
memcpy (data, "Exif", 4);
memcpy (data + 6, GST_BUFFER_DATA (exif_data),
GST_BUFFER_SIZE (exif_data));
m = gst_jif_mux_new_marker (APP1, GST_BUFFER_SIZE (exif_data) + 6, data,
TRUE);
gst_buffer_unref (exif_data);
if (app1_exif) {
gst_jif_mux_marker_free ((GstJifMuxMarker *) app1_exif->data);
app1_exif->data = m;
} else {
pos = file_hdr;
if (app0_jfif)
pos = app0_jfif;
pos = g_list_next (pos);
self->priv->markers =
g_list_insert_before (self->priv->markers, pos, m);
if (pos) {
app1_exif = g_list_previous (pos);
} else {
app1_exif = g_list_last (self->priv->markers);
}
}
modified = TRUE;
}
}
/* add xmp */
xmp_data =
gst_tag_xmp_writer_tag_list_to_xmp_buffer (GST_TAG_XMP_WRITER (self),
tags, FALSE);
if (xmp_data) {
guint8 *data, *xmp = GST_BUFFER_DATA (xmp_data);
guint size = GST_BUFFER_SIZE (xmp_data);
GList *pos;
data = g_malloc (size + 29);
memcpy (data, "http://ns.adobe.com/xap/1.0/\0", 29);
memcpy (&data[29], xmp, size);
m = gst_jif_mux_new_marker (APP1, size + 29, data, TRUE);
/*
* Replace the old xmp marker and not add a new one.
* There shouldn't be a xmp packet in the input, but it is better
* to be safe than add another one and end up with 2 packets.
*/
if (app1_xmp) {
gst_jif_mux_marker_free ((GstJifMuxMarker *) app1_xmp->data);
app1_xmp->data = m;
} else {
pos = file_hdr;
if (app1_exif)
pos = app1_exif;
else if (app0_jfif)
pos = app0_jfif;
pos = g_list_next (pos);
self->priv->markers = g_list_insert_before (self->priv->markers, pos, m);
}
gst_buffer_unref (xmp_data);
modified = TRUE;
}
/* add jpeg comment from any of those */
(void) (gst_tag_list_get_string (tags, GST_TAG_COMMENT, &str) ||
gst_tag_list_get_string (tags, GST_TAG_DESCRIPTION, &str) ||
gst_tag_list_get_string (tags, GST_TAG_TITLE, &str));
if (str) {
GST_DEBUG_OBJECT (self, "set COM marker to '%s'", str);
/* insert new marker into self->markers list */
m = gst_jif_mux_new_marker (COM, strlen (str) + 1, (const guint8 *) str,
TRUE);
/* FIXME: if we have one already, replace */
/* this should go before SOS, maybe at the end of file-header */
self->priv->markers = g_list_insert_before (self->priv->markers,
frame_hdr, m);
modified = TRUE;
}
if (tags && cleanup_tags)
gst_tag_list_free (tags);
return modified;
}
static GstFlowReturn
gst_jif_mux_recombine_image (GstJifMux * self, GstBuffer ** new_buf,
GstBuffer * old_buf)
{
GstBuffer *buf;
GstByteWriter *writer;
GstFlowReturn fret;
GstJifMuxMarker *m;
GList *node;
guint size = self->priv->scan_size;
gboolean writer_status = TRUE;
/* iterate list and collect size */
for (node = self->priv->markers; node; node = g_list_next (node)) {
m = (GstJifMuxMarker *) node->data;
/* some markers like e.g. SOI are empty */
if (m->size) {
size += 2 + m->size;
}
/* 0xff <marker> */
size += 2;
}
GST_INFO_OBJECT (self, "old size: %u, new size: %u",
GST_BUFFER_SIZE (old_buf), size);
/* allocate new buffer */
fret = gst_pad_alloc_buffer_and_set_caps (self->priv->srcpad,
GST_BUFFER_OFFSET (old_buf), size, GST_PAD_CAPS (self->priv->srcpad),
&buf);
if (fret != GST_FLOW_OK)
goto no_buffer;
/* copy buffer metadata */
gst_buffer_copy_metadata (buf, old_buf,
GST_BUFFER_COPY_FLAGS | GST_BUFFER_COPY_TIMESTAMPS);
/* memcopy markers */
writer = gst_byte_writer_new_with_buffer (buf, TRUE);
for (node = self->priv->markers; node && writer_status;
node = g_list_next (node)) {
m = (GstJifMuxMarker *) node->data;
writer_status &= gst_byte_writer_put_uint8 (writer, 0xff);
writer_status &= gst_byte_writer_put_uint8 (writer, m->marker);
GST_DEBUG_OBJECT (self, "marker = %2x, size = %u", m->marker, m->size + 2);
if (m->size) {
writer_status &= gst_byte_writer_put_uint16_be (writer, m->size + 2);
writer_status &= gst_byte_writer_put_data (writer, m->data, m->size);
}
if (m->marker == SOS) {
GST_DEBUG_OBJECT (self, "scan data, size = %u", self->priv->scan_size);
writer_status &=
gst_byte_writer_put_data (writer, self->priv->scan_data,
self->priv->scan_size);
}
}
gst_byte_writer_free (writer);
if (!writer_status) {
GST_WARNING_OBJECT (self, "Failed to write to buffer, calculated size "
"was probably too short");
g_assert_not_reached ();
}
*new_buf = buf;
return GST_FLOW_OK;
no_buffer:
GST_WARNING_OBJECT (self, "failed to allocate output buffer, flow_ret = %s",
gst_flow_get_name (fret));
return fret;
}
static GstFlowReturn
gst_jif_mux_chain (GstPad * pad, GstBuffer * buf)
{
GstJifMux *self = GST_JIF_MUX (GST_PAD_PARENT (pad));
GstFlowReturn fret = GST_FLOW_OK;
if (GST_BUFFER_CAPS (buf) == NULL) {
GST_WARNING_OBJECT (self, "Rejecting buffer without caps");
gst_buffer_unref (buf);
return GST_FLOW_NOT_NEGOTIATED;
}
GST_MEMDUMP ("jpeg beg", GST_BUFFER_DATA (buf), 64);
GST_MEMDUMP ("jpeg end", GST_BUFFER_DATA (buf) + GST_BUFFER_SIZE (buf) - 64,
64);
/* we should have received a whole picture from SOI to EOI
* build a list of markers */
if (gst_jif_mux_parse_image (self, buf)) {
/* modify marker list */
if (gst_jif_mux_mangle_markers (self)) {
/* the list was changed, remux */
GstBuffer *old = buf;
fret = gst_jif_mux_recombine_image (self, &buf, old);
gst_buffer_unref (old);
}
}
/* free the marker list */
gst_jif_mux_reset (self);
if (fret == GST_FLOW_OK) {
fret = gst_pad_push (self->priv->srcpad, buf);
}
return fret;
}
static GstStateChangeReturn
gst_jif_mux_change_state (GstElement * element, GstStateChange transition)
{
GstStateChangeReturn ret;
GstJifMux *self = GST_JIF_MUX_CAST (element);
switch (transition) {
case GST_STATE_CHANGE_NULL_TO_READY:
break;
case GST_STATE_CHANGE_READY_TO_PAUSED:
break;
case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
break;
default:
break;
}
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
switch (transition) {
case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
break;
case GST_STATE_CHANGE_PAUSED_TO_READY:
gst_tag_setter_reset_tags (GST_TAG_SETTER (self));
break;
case GST_STATE_CHANGE_READY_TO_NULL:
break;
default:
break;
}
return ret;
}