ext/rsvg/gstrsvgdec.c - imx-gst-plugins-bad - Git at Google

 /* GStreamer
  * Copyright (C) <2009> Sebastian Dröge <sebastian.droege@collabora.co.uk>
  * Copyright (C) <2013> Luciana Fujii <luciana.fujii@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., 51 Franklin St, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  */
 /**
  * SECTION:element-rsvgdec
  * @title: rsvgdec
  *
  * This elements renders SVG graphics.
  *
  * ## Example launch lines
  * |[
  * gst-launch-1.0 filesrc location=image.svg ! rsvgdec ! imagefreeze ! videoconvert ! autovideosink
  * ]| render and show a svg image.
  *
  */

 #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_MAKE ("BGRA")
 #define GST_RSVG_VIDEO_FORMAT GST_VIDEO_FORMAT_BGRA
 #else
 #define GST_RSVG_VIDEO_CAPS GST_VIDEO_CAPS_MAKE ("ARGB")
 #define GST_RSVG_VIDEO_FORMAT GST_VIDEO_FORMAT_ARGB
 #endif

 static GstStaticPadTemplate src_factory =
 GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
     GST_STATIC_CAPS (GST_RSVG_VIDEO_CAPS));

 #define gst_rsv_dec_parent_class parent_class
 G_DEFINE_TYPE (GstRsvgDec, gst_rsvg_dec, GST_TYPE_VIDEO_DECODER);

 static gboolean gst_rsvg_dec_stop (GstVideoDecoder * decoder);
 static gboolean gst_rsvg_dec_set_format (GstVideoDecoder * decoder,
     GstVideoCodecState * state);
 static GstFlowReturn gst_rsvg_dec_parse (GstVideoDecoder * decoder,
     GstVideoCodecFrame * frame, GstAdapter * adapter, gboolean at_eos);
 static GstFlowReturn gst_rsvg_dec_handle_frame (GstVideoDecoder * decoder,
     GstVideoCodecFrame * frame);
 static GstFlowReturn gst_rsvg_decode_image (GstRsvgDec * rsvg,
     GstBuffer * buffer, GstVideoCodecFrame * frame);

 static void gst_rsvg_dec_finalize (GObject * object);

 static void
 gst_rsvg_dec_class_init (GstRsvgDecClass * klass)
 {
   GstVideoDecoderClass *video_decoder_class = GST_VIDEO_DECODER_CLASS (klass);
   GObjectClass *gobject_class = (GObjectClass *) klass;
   GstElementClass *element_class = GST_ELEMENT_CLASS (klass);

   GST_DEBUG_CATEGORY_INIT (rsvgdec_debug, "rsvgdec", 0, "RSVG decoder");

   gst_element_class_set_static_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_static_pad_template (element_class, &sink_factory);
   gst_element_class_add_static_pad_template (element_class, &src_factory);

   gobject_class->finalize = gst_rsvg_dec_finalize;
   video_decoder_class->stop = GST_DEBUG_FUNCPTR (gst_rsvg_dec_stop);
   video_decoder_class->set_format = GST_DEBUG_FUNCPTR (gst_rsvg_dec_set_format);
   video_decoder_class->parse = GST_DEBUG_FUNCPTR (gst_rsvg_dec_parse);
   video_decoder_class->handle_frame =
       GST_DEBUG_FUNCPTR (gst_rsvg_dec_handle_frame);
 }

 static void
 gst_rsvg_dec_init (GstRsvgDec * rsvg)
 {
   GstVideoDecoder *decoder = GST_VIDEO_DECODER (rsvg);
   gst_video_decoder_set_packetized (decoder, FALSE);
   gst_video_decoder_set_use_default_pad_acceptcaps (GST_VIDEO_DECODER_CAST
       (rsvg), TRUE);
   GST_PAD_SET_ACCEPT_TEMPLATE (GST_VIDEO_DECODER_SINK_PAD (rsvg));
 }

 static void
 gst_rsvg_dec_finalize (GObject * object)
 {
   G_OBJECT_CLASS (gst_rsvg_dec_parent_class)->finalize (object);
 }


 #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, GstBuffer * buffer,
     GstVideoCodecFrame * frame)
 {
   GstVideoDecoder *decoder = GST_VIDEO_DECODER (rsvg);
   GstFlowReturn ret = GST_FLOW_OK;
   cairo_t *cr;
   cairo_surface_t *surface;
   RsvgHandle *handle;
   GError *error = NULL;
   RsvgDimensionData dimension;
   gdouble scalex, scaley;
   GstMapInfo minfo;
   GstVideoFrame vframe;
   GstVideoCodecState *output_state;

   GST_LOG_OBJECT (rsvg, "parsing svg");

   if (!gst_buffer_map (buffer, &minfo, GST_MAP_READ)) {
     GST_ERROR_OBJECT (rsvg, "Failed to get SVG image");
     return GST_FLOW_ERROR;
   }
   handle = rsvg_handle_new_from_data (minfo.data, minfo.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);

   output_state = gst_video_decoder_get_output_state (decoder);
   if ((output_state == NULL)
       || GST_VIDEO_INFO_WIDTH (&output_state->info) != dimension.width
       || GST_VIDEO_INFO_HEIGHT (&output_state->info) != dimension.height) {

     /* Create the output state */
     if (output_state)
       gst_video_codec_state_unref (output_state);
     output_state =
         gst_video_decoder_set_output_state (decoder, GST_RSVG_VIDEO_FORMAT,
         dimension.width, dimension.height, rsvg->input_state);
   }

   ret = gst_video_decoder_allocate_output_frame (decoder, frame);

   if (ret != GST_FLOW_OK) {
     g_object_unref (handle);
     gst_video_codec_state_unref (output_state);
     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",
       GST_VIDEO_INFO_HEIGHT (&output_state->info),
       GST_VIDEO_INFO_WIDTH (&output_state->info));


   if (!gst_video_frame_map (&vframe,
           &output_state->info, frame->output_buffer, GST_MAP_READWRITE)) {
     GST_ERROR_OBJECT (rsvg, "Failed to get SVG image");
     g_object_unref (handle);
     gst_video_codec_state_unref (output_state);
     return GST_FLOW_ERROR;
   }
   surface =
       cairo_image_surface_create_for_data (GST_VIDEO_FRAME_PLANE_DATA (&vframe,
           0), CAIRO_FORMAT_ARGB32, GST_VIDEO_FRAME_WIDTH (&vframe),
       GST_VIDEO_FRAME_HEIGHT (&vframe), GST_VIDEO_FRAME_PLANE_STRIDE (&vframe,
           0));

   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 (GST_VIDEO_INFO_WIDTH (&output_state->info) != dimension.width) {
     scalex =
         ((gdouble) GST_VIDEO_INFO_WIDTH (&output_state->info)) /
         ((gdouble) dimension.width);
   }
   if (GST_VIDEO_INFO_HEIGHT (&output_state->info) != dimension.height) {
     scaley =
         ((gdouble) GST_VIDEO_INFO_HEIGHT (&output_state->info)) /
         ((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_VIDEO_FRAME_PLANE_DATA (&vframe, 0),
       GST_VIDEO_FRAME_WIDTH (&vframe), GST_VIDEO_FRAME_HEIGHT (&vframe));

   gst_video_codec_state_unref (output_state);
   gst_buffer_unmap (buffer, &minfo);
   gst_video_frame_unmap (&vframe);

   return ret;
 }


 static gboolean
 gst_rsvg_dec_set_format (GstVideoDecoder * decoder, GstVideoCodecState * state)
 {
   GstRsvgDec *rsvg = GST_RSVG_DEC (decoder);
   GstVideoInfo *info = &state->info;

   if (rsvg->input_state)
     gst_video_codec_state_unref (rsvg->input_state);
   rsvg->input_state = gst_video_codec_state_ref (state);

   /* Create the output state */
   state = gst_video_decoder_set_output_state (decoder, GST_RSVG_VIDEO_FORMAT,
       GST_VIDEO_INFO_WIDTH (info), GST_VIDEO_INFO_HEIGHT (info),
       rsvg->input_state);
   gst_video_codec_state_unref (state);

   return TRUE;
 }

 static GstFlowReturn
 gst_rsvg_dec_parse (GstVideoDecoder * decoder, GstVideoCodecFrame * frame,
     GstAdapter * adapter, gboolean at_eos)
 {
   gboolean completed = FALSE;
   const guint8 *data;
   guint size;
   guint i;

   GST_LOG_OBJECT (decoder, "parse start");
   size = gst_adapter_available (adapter);

   /* "<svg></svg>" */
   if (size < 5 + 6)
     return GST_VIDEO_DECODER_FLOW_NEED_DATA;

   data = gst_adapter_map (adapter, size);
   if (data == NULL) {
     GST_ERROR_OBJECT (decoder, "Unable to map memory");
     return GST_FLOW_ERROR;
   }
   for (i = 0; i < size - 4; i++) {
     if (memcmp (data + i, "<svg", 4) == 0) {
       gst_adapter_flush (adapter, i);

       size = gst_adapter_available (adapter);
       if (size < 5 + 6)
         return GST_VIDEO_DECODER_FLOW_NEED_DATA;
       data = gst_adapter_map (adapter, size);
       if (data == NULL) {
         GST_ERROR_OBJECT (decoder, "Unable to map memory");
         return GST_FLOW_ERROR;
       }
       break;
     }
   }
   /* If start wasn't found: */
   if (i == size - 4) {
     gst_adapter_flush (adapter, size - 4);
     return GST_VIDEO_DECODER_FLOW_NEED_DATA;
   }

   for (i = size - 6; i >= 5; i--) {
     if (memcmp (data + i, "</svg>", 6) == 0) {
       completed = TRUE;
       size = i + 6;
       break;
     }
   }

   if (completed) {

     GST_LOG_OBJECT (decoder, "have complete svg of %u bytes", size);

     gst_video_decoder_add_to_frame (decoder, size);
     return gst_video_decoder_have_frame (decoder);
   }
   return GST_VIDEO_DECODER_FLOW_NEED_DATA;
 }

 static GstFlowReturn
 gst_rsvg_dec_handle_frame (GstVideoDecoder * decoder,
     GstVideoCodecFrame * frame)
 {
   GstRsvgDec *rsvg = GST_RSVG_DEC (decoder);
   gboolean ret;

   ret = gst_rsvg_decode_image (rsvg, frame->input_buffer, frame);
   switch (ret) {
     case GST_FLOW_OK:
       ret = gst_video_decoder_finish_frame (decoder, frame);
       break;
     default:
       gst_video_codec_frame_unref (frame);
       break;
   }

   GST_LOG_OBJECT (rsvg, "Handle frame done");
   return ret;
 }

 static gboolean
 gst_rsvg_dec_stop (GstVideoDecoder * decoder)
 {
   GstRsvgDec *rsvg = GST_RSVG_DEC (decoder);

   if (rsvg->input_state) {
     gst_video_codec_state_unref (rsvg->input_state);
     rsvg->input_state = NULL;
   }

   return TRUE;
 }
	/* GStreamer
	* Copyright (C) <2009> Sebastian Dröge <sebastian.droege@collabora.co.uk>
	* Copyright (C) <2013> Luciana Fujii <luciana.fujii@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., 51 Franklin St, Fifth Floor,
	* Boston, MA 02110-1301, USA.
	*/
	/**
	* SECTION:element-rsvgdec
	* @title: rsvgdec
	*
	* This elements renders SVG graphics.
	*
	* ## Example launch lines
	* \|[
	* gst-launch-1.0 filesrc location=image.svg ! rsvgdec ! imagefreeze ! videoconvert ! autovideosink
	* ]\| render and show a svg image.
	*
	*/

	#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_MAKE ("BGRA")
	#define GST_RSVG_VIDEO_FORMAT GST_VIDEO_FORMAT_BGRA
	#else
	#define GST_RSVG_VIDEO_CAPS GST_VIDEO_CAPS_MAKE ("ARGB")
	#define GST_RSVG_VIDEO_FORMAT GST_VIDEO_FORMAT_ARGB
	#endif

	static GstStaticPadTemplate src_factory =
	GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
	GST_STATIC_CAPS (GST_RSVG_VIDEO_CAPS));

	#define gst_rsv_dec_parent_class parent_class
	G_DEFINE_TYPE (GstRsvgDec, gst_rsvg_dec, GST_TYPE_VIDEO_DECODER);

	static gboolean gst_rsvg_dec_stop (GstVideoDecoder * decoder);
	static gboolean gst_rsvg_dec_set_format (GstVideoDecoder * decoder,
	GstVideoCodecState * state);
	static GstFlowReturn gst_rsvg_dec_parse (GstVideoDecoder * decoder,
	GstVideoCodecFrame * frame, GstAdapter * adapter, gboolean at_eos);
	static GstFlowReturn gst_rsvg_dec_handle_frame (GstVideoDecoder * decoder,
	GstVideoCodecFrame * frame);
	static GstFlowReturn gst_rsvg_decode_image (GstRsvgDec * rsvg,
	GstBuffer * buffer, GstVideoCodecFrame * frame);

	static void gst_rsvg_dec_finalize (GObject * object);

	static void
	gst_rsvg_dec_class_init (GstRsvgDecClass * klass)
	{
	GstVideoDecoderClass *video_decoder_class = GST_VIDEO_DECODER_CLASS (klass);
	GObjectClass gobject_class = (GObjectClass ) klass;
	GstElementClass *element_class = GST_ELEMENT_CLASS (klass);

	GST_DEBUG_CATEGORY_INIT (rsvgdec_debug, "rsvgdec", 0, "RSVG decoder");

	gst_element_class_set_static_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_static_pad_template (element_class, &sink_factory);
	gst_element_class_add_static_pad_template (element_class, &src_factory);

	gobject_class->finalize = gst_rsvg_dec_finalize;
	video_decoder_class->stop = GST_DEBUG_FUNCPTR (gst_rsvg_dec_stop);
	video_decoder_class->set_format = GST_DEBUG_FUNCPTR (gst_rsvg_dec_set_format);
	video_decoder_class->parse = GST_DEBUG_FUNCPTR (gst_rsvg_dec_parse);
	video_decoder_class->handle_frame =
	GST_DEBUG_FUNCPTR (gst_rsvg_dec_handle_frame);
	}

	static void
	gst_rsvg_dec_init (GstRsvgDec * rsvg)
	{
	GstVideoDecoder *decoder = GST_VIDEO_DECODER (rsvg);
	gst_video_decoder_set_packetized (decoder, FALSE);
	gst_video_decoder_set_use_default_pad_acceptcaps (GST_VIDEO_DECODER_CAST
	(rsvg), TRUE);
	GST_PAD_SET_ACCEPT_TEMPLATE (GST_VIDEO_DECODER_SINK_PAD (rsvg));
	}

	static void
	gst_rsvg_dec_finalize (GObject * object)
	{
	G_OBJECT_CLASS (gst_rsvg_dec_parent_class)->finalize (object);
	}


	#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, GstBuffer * buffer,
	GstVideoCodecFrame * frame)
	{
	GstVideoDecoder *decoder = GST_VIDEO_DECODER (rsvg);
	GstFlowReturn ret = GST_FLOW_OK;
	cairo_t *cr;
	cairo_surface_t *surface;
	RsvgHandle *handle;
	GError *error = NULL;
	RsvgDimensionData dimension;
	gdouble scalex, scaley;
	GstMapInfo minfo;
	GstVideoFrame vframe;
	GstVideoCodecState *output_state;

	GST_LOG_OBJECT (rsvg, "parsing svg");

	if (!gst_buffer_map (buffer, &minfo, GST_MAP_READ)) {
	GST_ERROR_OBJECT (rsvg, "Failed to get SVG image");
	return GST_FLOW_ERROR;
	}
	handle = rsvg_handle_new_from_data (minfo.data, minfo.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);

	output_state = gst_video_decoder_get_output_state (decoder);
	if ((output_state == NULL)
	\|\| GST_VIDEO_INFO_WIDTH (&output_state->info) != dimension.width
	\|\| GST_VIDEO_INFO_HEIGHT (&output_state->info) != dimension.height) {

	/* Create the output state */
	if (output_state)
	gst_video_codec_state_unref (output_state);
	output_state =
	gst_video_decoder_set_output_state (decoder, GST_RSVG_VIDEO_FORMAT,
	dimension.width, dimension.height, rsvg->input_state);
	}

	ret = gst_video_decoder_allocate_output_frame (decoder, frame);

	if (ret != GST_FLOW_OK) {
	g_object_unref (handle);
	gst_video_codec_state_unref (output_state);
	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",
	GST_VIDEO_INFO_HEIGHT (&output_state->info),
	GST_VIDEO_INFO_WIDTH (&output_state->info));


	if (!gst_video_frame_map (&vframe,
	&output_state->info, frame->output_buffer, GST_MAP_READWRITE)) {
	GST_ERROR_OBJECT (rsvg, "Failed to get SVG image");
	g_object_unref (handle);
	gst_video_codec_state_unref (output_state);
	return GST_FLOW_ERROR;
	}
	surface =
	cairo_image_surface_create_for_data (GST_VIDEO_FRAME_PLANE_DATA (&vframe,
	0), CAIRO_FORMAT_ARGB32, GST_VIDEO_FRAME_WIDTH (&vframe),
	GST_VIDEO_FRAME_HEIGHT (&vframe), GST_VIDEO_FRAME_PLANE_STRIDE (&vframe,
	0));

	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 (GST_VIDEO_INFO_WIDTH (&output_state->info) != dimension.width) {
	scalex =
	((gdouble) GST_VIDEO_INFO_WIDTH (&output_state->info)) /
	((gdouble) dimension.width);
	}
	if (GST_VIDEO_INFO_HEIGHT (&output_state->info) != dimension.height) {
	scaley =
	((gdouble) GST_VIDEO_INFO_HEIGHT (&output_state->info)) /
	((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_VIDEO_FRAME_PLANE_DATA (&vframe, 0),
	GST_VIDEO_FRAME_WIDTH (&vframe), GST_VIDEO_FRAME_HEIGHT (&vframe));

	gst_video_codec_state_unref (output_state);
	gst_buffer_unmap (buffer, &minfo);
	gst_video_frame_unmap (&vframe);

	return ret;
	}


	static gboolean
	gst_rsvg_dec_set_format (GstVideoDecoder * decoder, GstVideoCodecState * state)
	{
	GstRsvgDec *rsvg = GST_RSVG_DEC (decoder);
	GstVideoInfo *info = &state->info;

	if (rsvg->input_state)
	gst_video_codec_state_unref (rsvg->input_state);
	rsvg->input_state = gst_video_codec_state_ref (state);

	/* Create the output state */
	state = gst_video_decoder_set_output_state (decoder, GST_RSVG_VIDEO_FORMAT,
	GST_VIDEO_INFO_WIDTH (info), GST_VIDEO_INFO_HEIGHT (info),
	rsvg->input_state);
	gst_video_codec_state_unref (state);

	return TRUE;
	}

	static GstFlowReturn
	gst_rsvg_dec_parse (GstVideoDecoder * decoder, GstVideoCodecFrame * frame,
	GstAdapter * adapter, gboolean at_eos)
	{
	gboolean completed = FALSE;
	const guint8 *data;
	guint size;
	guint i;

	GST_LOG_OBJECT (decoder, "parse start");
	size = gst_adapter_available (adapter);

	/* "<svg></svg>" */
	if (size < 5 + 6)
	return GST_VIDEO_DECODER_FLOW_NEED_DATA;

	data = gst_adapter_map (adapter, size);
	if (data == NULL) {
	GST_ERROR_OBJECT (decoder, "Unable to map memory");
	return GST_FLOW_ERROR;
	}
	for (i = 0; i < size - 4; i++) {
	if (memcmp (data + i, "<svg", 4) == 0) {
	gst_adapter_flush (adapter, i);

	size = gst_adapter_available (adapter);
	if (size < 5 + 6)
	return GST_VIDEO_DECODER_FLOW_NEED_DATA;
	data = gst_adapter_map (adapter, size);
	if (data == NULL) {
	GST_ERROR_OBJECT (decoder, "Unable to map memory");
	return GST_FLOW_ERROR;
	}
	break;
	}
	}
	/* If start wasn't found: */
	if (i == size - 4) {
	gst_adapter_flush (adapter, size - 4);
	return GST_VIDEO_DECODER_FLOW_NEED_DATA;
	}

	for (i = size - 6; i >= 5; i--) {
	if (memcmp (data + i, "</svg>", 6) == 0) {
	completed = TRUE;
	size = i + 6;
	break;
	}
	}

	if (completed) {

	GST_LOG_OBJECT (decoder, "have complete svg of %u bytes", size);

	gst_video_decoder_add_to_frame (decoder, size);
	return gst_video_decoder_have_frame (decoder);
	}
	return GST_VIDEO_DECODER_FLOW_NEED_DATA;
	}

	static GstFlowReturn
	gst_rsvg_dec_handle_frame (GstVideoDecoder * decoder,
	GstVideoCodecFrame * frame)
	{
	GstRsvgDec *rsvg = GST_RSVG_DEC (decoder);
	gboolean ret;

	ret = gst_rsvg_decode_image (rsvg, frame->input_buffer, frame);
	switch (ret) {
	case GST_FLOW_OK:
	ret = gst_video_decoder_finish_frame (decoder, frame);
	break;
	default:
	gst_video_codec_frame_unref (frame);
	break;
	}

	GST_LOG_OBJECT (rsvg, "Handle frame done");
	return ret;
	}

	static gboolean
	gst_rsvg_dec_stop (GstVideoDecoder * decoder)
	{
	GstRsvgDec *rsvg = GST_RSVG_DEC (decoder);

	if (rsvg->input_state) {
	gst_video_codec_state_unref (rsvg->input_state);
	rsvg->input_state = NULL;
	}

	return TRUE;
	}