gstreamer/ext/rsvg/gstrsvgdec.c

575 lines
17 KiB
C

/* GStreamer
* Copyright (C) <2009> Sebastian Dröge <sebastian.droege@collabora.co.uk>
*
* 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-rsvgdec
*
* This elements renders SVG graphics.
*
* <refsect2>
* <title>Example launch lines</title>
* |[
* gst-launch filesrc location=image.svg ! rsvgdec ! imagefreeze ! videoconvert ! autovideosink
* ]| render and show a svg image.
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "gstrsvgdec.h"
#include <string.h>
GST_DEBUG_CATEGORY_STATIC (rsvgdec_debug);
#define GST_CAT_DEFAULT rsvgdec_debug
static GstStaticPadTemplate sink_factory =
GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS,
GST_STATIC_CAPS ("image/svg+xml; image/svg"));
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
#define GST_RSVG_VIDEO_CAPS GST_VIDEO_CAPS_BGRA
#else
#define GST_RSVG_VIDEO_CAPS GST_VIDEO_CAPS_ARGB
#endif
static GstStaticPadTemplate src_factory =
GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
GST_STATIC_CAPS (GST_RSVG_VIDEO_CAPS));
GST_BOILERPLATE (GstRsvgDec, gst_rsvg_dec, GstElement, GST_TYPE_ELEMENT);
static void gst_rsvg_dec_reset (GstRsvgDec * rsvg);
static GstFlowReturn gst_rsvg_dec_chain (GstPad * pad, GstBuffer * buffer);
static gboolean gst_rsvg_dec_sink_set_caps (GstPad * pad, GstCaps * caps);
static gboolean gst_rsvg_dec_sink_event (GstPad * pad, GstEvent * event);
static gboolean gst_rsvg_dec_src_event (GstPad * pad, GstEvent * event);
static gboolean gst_rsvg_dec_src_query (GstPad * pad, GstQuery * query);
static const GstQueryType *gst_rsvg_dec_src_query_type (GstPad * pad);
static gboolean gst_rsvg_dec_src_set_caps (GstPad * pad, GstCaps * caps);
static GstStateChangeReturn gst_rsvg_dec_change_state (GstElement * element,
GstStateChange transition);
static void gst_rsvg_dec_finalize (GObject * object);
static void
gst_rsvg_dec_base_init (gpointer g_class)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
gst_element_class_set_metadata (element_class,
"SVG image decoder", "Codec/Decoder/Image",
"Uses librsvg to decode SVG images",
"Sebastian Dröge <sebastian.droege@collabora.co.uk>");
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&sink_factory));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&src_factory));
}
static void
gst_rsvg_dec_class_init (GstRsvgDecClass * klass)
{
GstElementClass *element_class = (GstElementClass *) klass;
GObjectClass *gobject_class = (GObjectClass *) klass;
GST_DEBUG_CATEGORY_INIT (rsvgdec_debug, "rsvgdec", 0, "RSVG decoder");
gobject_class->finalize = gst_rsvg_dec_finalize;
element_class->change_state = GST_DEBUG_FUNCPTR (gst_rsvg_dec_change_state);
}
static void
gst_rsvg_dec_init (GstRsvgDec * rsvg, GstRsvgDecClass * klass)
{
rsvg->sinkpad = gst_pad_new_from_static_template (&sink_factory, "sink");
gst_pad_set_setcaps_function (rsvg->sinkpad, gst_rsvg_dec_sink_set_caps);
gst_pad_set_event_function (rsvg->sinkpad, gst_rsvg_dec_sink_event);
gst_pad_set_chain_function (rsvg->sinkpad, gst_rsvg_dec_chain);
gst_element_add_pad (GST_ELEMENT (rsvg), rsvg->sinkpad);
rsvg->srcpad = gst_pad_new_from_static_template (&src_factory, "src");
gst_pad_set_event_function (rsvg->srcpad, gst_rsvg_dec_src_event);
gst_pad_set_query_function (rsvg->srcpad, gst_rsvg_dec_src_query);
gst_pad_set_query_type_function (rsvg->srcpad, gst_rsvg_dec_src_query_type);
gst_pad_set_setcaps_function (rsvg->srcpad, gst_rsvg_dec_src_set_caps);
gst_element_add_pad (GST_ELEMENT (rsvg), rsvg->srcpad);
rsvg->adapter = gst_adapter_new ();
gst_rsvg_dec_reset (rsvg);
}
static void
gst_rsvg_dec_finalize (GObject * object)
{
GstRsvgDec *rsvg = GST_RSVG_DEC (object);
if (rsvg->adapter) {
g_object_unref (rsvg->adapter);
rsvg->adapter = NULL;
}
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static void
gst_rsvg_dec_reset (GstRsvgDec * dec)
{
gst_adapter_clear (dec->adapter);
dec->width = dec->height = 0;
dec->fps_n = 0;
dec->fps_d = 1;
dec->first_timestamp = GST_CLOCK_TIME_NONE;
dec->frame_count = 0;
gst_segment_init (&dec->segment, GST_FORMAT_UNDEFINED);
dec->need_newsegment = TRUE;
g_list_foreach (dec->pending_events, (GFunc) gst_mini_object_unref, NULL);
g_list_free (dec->pending_events);
dec->pending_events = NULL;
}
#define CAIRO_UNPREMULTIPLY(a,r,g,b) G_STMT_START { \
b = (a > 0) ? MIN ((b * 255 + a / 2) / a, 255) : 0; \
g = (a > 0) ? MIN ((g * 255 + a / 2) / a, 255) : 0; \
r = (a > 0) ? MIN ((r * 255 + a / 2) / a, 255) : 0; \
} G_STMT_END
static void
gst_rsvg_decode_unpremultiply (guint8 * data, gint width, gint height)
{
gint i, j;
guint a;
for (i = 0; i < height; i++) {
for (j = 0; j < width; j++) {
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
a = data[3];
data[0] = (a > 0) ? MIN ((data[0] * 255 + a / 2) / a, 255) : 0;
data[1] = (a > 0) ? MIN ((data[1] * 255 + a / 2) / a, 255) : 0;
data[2] = (a > 0) ? MIN ((data[2] * 255 + a / 2) / a, 255) : 0;
#else
a = data[0];
data[1] = (a > 0) ? MIN ((data[1] * 255 + a / 2) / a, 255) : 0;
data[2] = (a > 0) ? MIN ((data[2] * 255 + a / 2) / a, 255) : 0;
data[3] = (a > 0) ? MIN ((data[3] * 255 + a / 2) / a, 255) : 0;
#endif
data += 4;
}
}
}
static GstFlowReturn
gst_rsvg_decode_image (GstRsvgDec * rsvg, const guint8 * data, guint size,
GstBuffer ** buffer)
{
GstFlowReturn ret = GST_FLOW_OK;
cairo_t *cr;
cairo_surface_t *surface;
RsvgHandle *handle;
GError *error = NULL;
RsvgDimensionData dimension;
gdouble scalex, scaley;
GST_LOG_OBJECT (rsvg, "parsing svg");
handle = rsvg_handle_new_from_data (data, size, &error);
if (!handle) {
GST_ERROR_OBJECT (rsvg, "Failed to parse SVG image: %s", error->message);
g_error_free (error);
return GST_FLOW_ERROR;
}
rsvg_handle_get_dimensions (handle, &dimension);
if (rsvg->width != dimension.width || rsvg->height != dimension.height) {
GstCaps *caps1, *caps2, *caps3;
GstStructure *s;
GST_LOG_OBJECT (rsvg, "resolution changed, updating caps");
caps1 = gst_caps_copy (gst_pad_get_pad_template_caps (rsvg->srcpad));
caps2 = gst_pad_peer_get_caps (rsvg->srcpad);
if (caps2) {
caps3 = gst_caps_intersect (caps1, caps2);
gst_caps_unref (caps1);
gst_caps_unref (caps2);
caps1 = caps3;
caps3 = NULL;
}
if (gst_caps_is_empty (caps1)) {
GST_ERROR_OBJECT (rsvg, "Unable to negotiate a format");
gst_caps_unref (caps1);
g_object_unref (handle);
return GST_FLOW_NOT_NEGOTIATED;
}
caps2 = gst_caps_copy (gst_pad_get_pad_template_caps (rsvg->srcpad));
s = gst_caps_get_structure (caps2, 0);
gst_structure_set (s, "width", G_TYPE_INT, dimension.width, "height",
G_TYPE_INT, dimension.height, "framerate", GST_TYPE_FRACTION, 0, 1,
NULL);
caps3 = gst_caps_intersect (caps1, caps2);
if (!gst_caps_is_empty (caps3)) {
gst_caps_truncate (caps3);
gst_pad_set_caps (rsvg->srcpad, caps3);
gst_caps_unref (caps1);
gst_caps_unref (caps2);
gst_caps_unref (caps3);
rsvg->width = dimension.width;
rsvg->height = dimension.height;
} else {
gst_caps_unref (caps2);
gst_caps_unref (caps3);
gst_caps_truncate (caps1);
s = gst_caps_get_structure (caps1, 0);
gst_structure_set (s, "framerate", GST_TYPE_FRACTION, 0, 1, NULL);
if (!gst_caps_is_fixed (caps1)
&& (!gst_structure_fixate_field_nearest_int (s, "width",
dimension.width)
|| !gst_structure_fixate_field_nearest_int (s, "height",
dimension.height))) {
g_object_unref (handle);
GST_ERROR_OBJECT (rsvg, "Failed to fixate caps");
return GST_FLOW_NOT_NEGOTIATED;
}
gst_pad_set_caps (rsvg->srcpad, caps1);
gst_structure_get_int (s, "width", &rsvg->width);
gst_structure_get_int (s, "height", &rsvg->height);
gst_caps_unref (caps1);
}
}
if ((ret = gst_pad_alloc_buffer_and_set_caps (rsvg->srcpad,
GST_BUFFER_OFFSET_NONE,
rsvg->width * rsvg->height * 4,
GST_PAD_CAPS (rsvg->srcpad), buffer)) != GST_FLOW_OK) {
g_object_unref (handle);
GST_ERROR_OBJECT (rsvg, "Buffer allocation failed %s",
gst_flow_get_name (ret));
return ret;
}
GST_LOG_OBJECT (rsvg, "render image at %d x %d", rsvg->height, rsvg->width);
surface =
cairo_image_surface_create_for_data (GST_BUFFER_DATA (*buffer),
CAIRO_FORMAT_ARGB32, rsvg->width, rsvg->height, rsvg->width * 4);
cr = cairo_create (surface);
cairo_set_operator (cr, CAIRO_OPERATOR_CLEAR);
cairo_set_source_rgba (cr, 1.0, 1.0, 1.0, 0.0);
cairo_paint (cr);
cairo_set_operator (cr, CAIRO_OPERATOR_OVER);
cairo_set_source_rgba (cr, 0.0, 0.0, 0.0, 1.0);
scalex = scaley = 1.0;
if (rsvg->width != dimension.width) {
scalex = ((gdouble) rsvg->width) / ((gdouble) dimension.width);
}
if (rsvg->height != dimension.height) {
scaley = ((gdouble) rsvg->height) / ((gdouble) dimension.height);
}
cairo_scale (cr, scalex, scaley);
rsvg_handle_render_cairo (handle, cr);
g_object_unref (handle);
cairo_destroy (cr);
cairo_surface_destroy (surface);
/* Now unpremultiply Cairo's ARGB to match GStreamer's */
gst_rsvg_decode_unpremultiply (GST_BUFFER_DATA (*buffer), rsvg->width,
rsvg->height);
return ret;
}
static GstFlowReturn
gst_rsvg_dec_chain (GstPad * pad, GstBuffer * buffer)
{
GstRsvgDec *rsvg = GST_RSVG_DEC (GST_PAD_PARENT (pad));
gboolean completed = FALSE;
const guint8 *data;
guint size;
gboolean ret = GST_FLOW_OK;
/* first_timestamp is used slightly differently where a framerate
is given or not.
If there is a frame rate, it will be used as a base.
If there is not, it will be used to keep track of the timestamp
of the first buffer, to be used as the timestamp of the output
buffer. When a buffer is output, first timestamp will resync to
the next buffer's timestamp. */
if (rsvg->first_timestamp == GST_CLOCK_TIME_NONE) {
if (GST_BUFFER_TIMESTAMP_IS_VALID (buffer))
rsvg->first_timestamp = GST_BUFFER_TIMESTAMP (buffer);
else if (rsvg->fps_n != 0)
rsvg->first_timestamp = 0;
}
gst_adapter_push (rsvg->adapter, buffer);
size = gst_adapter_available (rsvg->adapter);
/* "<svg></svg>" */
while (size >= 5 + 6 && ret == GST_FLOW_OK) {
guint i;
data = gst_adapter_peek (rsvg->adapter, size);
for (i = size - 6; i >= 5; i--) {
if (memcmp (data + i, "</svg>", 6) == 0) {
completed = TRUE;
size = i + 6;
break;
}
}
if (completed) {
GstBuffer *outbuf = NULL;
GST_LOG_OBJECT (rsvg, "have complete svg of %u bytes", size);
data = gst_adapter_peek (rsvg->adapter, size);
ret = gst_rsvg_decode_image (rsvg, data, size, &outbuf);
if (ret != GST_FLOW_OK)
break;
if (rsvg->first_timestamp != GST_CLOCK_TIME_NONE) {
GST_BUFFER_TIMESTAMP (outbuf) = rsvg->first_timestamp;
GST_BUFFER_DURATION (outbuf) = GST_CLOCK_TIME_NONE;
if (GST_BUFFER_DURATION_IS_VALID (buffer)) {
GstClockTime end =
GST_BUFFER_TIMESTAMP_IS_VALID (buffer) ?
GST_BUFFER_TIMESTAMP (buffer) : rsvg->first_timestamp;
end += GST_BUFFER_DURATION (buffer);
GST_BUFFER_DURATION (outbuf) = end - GST_BUFFER_TIMESTAMP (outbuf);
}
if (rsvg->fps_n == 0) {
rsvg->first_timestamp = GST_CLOCK_TIME_NONE;
} else {
GST_BUFFER_DURATION (outbuf) =
gst_util_uint64_scale (rsvg->frame_count, rsvg->fps_d,
rsvg->fps_n * GST_SECOND);
}
} else if (rsvg->fps_n != 0) {
GST_BUFFER_TIMESTAMP (outbuf) =
rsvg->first_timestamp + gst_util_uint64_scale (rsvg->frame_count,
rsvg->fps_d, rsvg->fps_n * GST_SECOND);
GST_BUFFER_DURATION (outbuf) =
gst_util_uint64_scale (rsvg->frame_count, rsvg->fps_d,
rsvg->fps_n * GST_SECOND);
} else {
GST_BUFFER_TIMESTAMP (outbuf) = rsvg->first_timestamp;
GST_BUFFER_DURATION (outbuf) = GST_CLOCK_TIME_NONE;
}
rsvg->frame_count++;
if (rsvg->need_newsegment) {
gst_pad_push_event (rsvg->srcpad,
gst_event_new_new_segment (FALSE, 1.0, GST_FORMAT_TIME, 0, -1, 0));
rsvg->need_newsegment = FALSE;
}
if (rsvg->pending_events) {
GList *l;
for (l = rsvg->pending_events; l; l = l->next)
gst_pad_push_event (rsvg->srcpad, l->data);
g_list_free (rsvg->pending_events);
rsvg->pending_events = NULL;
}
GST_LOG_OBJECT (rsvg, "image rendered okay");
ret = gst_pad_push (rsvg->srcpad, outbuf);
if (ret != GST_FLOW_OK)
break;
gst_adapter_flush (rsvg->adapter, size);
size = gst_adapter_available (rsvg->adapter);
continue;
} else {
break;
}
}
return GST_FLOW_OK;
}
static gboolean
gst_rsvg_dec_sink_set_caps (GstPad * pad, GstCaps * caps)
{
GstRsvgDec *rsvg = GST_RSVG_DEC (gst_pad_get_parent (pad));
gboolean ret = TRUE;
GstStructure *s = gst_caps_get_structure (caps, 0);
gst_structure_get_fraction (s, "framerate", &rsvg->fps_n, &rsvg->fps_d);
gst_object_unref (rsvg);
return ret;
}
static gboolean
gst_rsvg_dec_sink_event (GstPad * pad, GstEvent * event)
{
GstRsvgDec *rsvg = GST_RSVG_DEC (gst_pad_get_parent (pad));
gboolean res = FALSE;
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_NEWSEGMENT:{
gdouble rate, arate;
gboolean update;
gint64 start, stop, position;
GstFormat fmt;
gst_event_parse_new_segment_full (event, &update, &rate, &arate, &fmt,
&start, &stop, &position);
gst_segment_set_newsegment_full (&rsvg->segment, update, rate, arate,
fmt, start, stop, position);
if (fmt == GST_FORMAT_TIME) {
rsvg->need_newsegment = FALSE;
res = gst_pad_push_event (rsvg->srcpad, event);
} else {
gst_event_unref (event);
res = TRUE;
}
break;
}
case GST_EVENT_EOS:
case GST_EVENT_FLUSH_STOP:
gst_adapter_clear (rsvg->adapter);
/* fall through */
case GST_EVENT_FLUSH_START:
res = gst_pad_push_event (rsvg->srcpad, event);
break;
default:
if (GST_PAD_CAPS (rsvg->srcpad)) {
res = gst_pad_push_event (rsvg->srcpad, event);
} else {
res = TRUE;
rsvg->pending_events = g_list_append (rsvg->pending_events, event);
}
break;
}
gst_object_unref (rsvg);
return res;
}
static gboolean
gst_rsvg_dec_src_event (GstPad * pad, GstEvent * event)
{
GstRsvgDec *rsvg = GST_RSVG_DEC (gst_pad_get_parent (pad));
gboolean res = FALSE;
switch (GST_EVENT_TYPE (event)) {
default:
res = gst_pad_push_event (rsvg->sinkpad, event);
break;
}
gst_object_unref (rsvg);
return res;
}
static const GstQueryType *
gst_rsvg_dec_src_query_type (GstPad * pad)
{
static const GstQueryType query_types[] = {
(GstQueryType) 0
};
return query_types;
}
static gboolean
gst_rsvg_dec_src_query (GstPad * pad, GstQuery * query)
{
GstRsvgDec *rsvg = GST_RSVG_DEC (gst_pad_get_parent (pad));
gboolean res = TRUE;
switch (GST_QUERY_TYPE (query)) {
default:
res = gst_pad_query_default (pad, query);
break;
}
gst_object_unref (rsvg);
return res;
}
static gboolean
gst_rsvg_dec_src_set_caps (GstPad * pad, GstCaps * caps)
{
GstRsvgDec *rsvg = GST_RSVG_DEC (gst_pad_get_parent (pad));
gboolean ret = TRUE;
GstStructure *s = gst_caps_get_structure (caps, 0);
ret &= gst_structure_get_int (s, "width", &rsvg->width);
ret &= gst_structure_get_int (s, "height", &rsvg->height);
gst_object_unref (rsvg);
return ret;
}
static GstStateChangeReturn
gst_rsvg_dec_change_state (GstElement * element, GstStateChange transition)
{
GstStateChangeReturn res;
GstRsvgDec *dec = GST_RSVG_DEC (element);
switch (transition) {
case GST_STATE_CHANGE_READY_TO_PAUSED:
break;
default:
break;
}
res = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
if (res == GST_STATE_CHANGE_FAILURE)
return res;
switch (transition) {
case GST_STATE_CHANGE_PAUSED_TO_READY:
gst_rsvg_dec_reset (dec);
break;
default:
break;
}
return res;
}