diff -r 000000000000 -r 0e761a78d257 gst_plugins_base/gst/videoscale/gstvideoscale.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gst_plugins_base/gst/videoscale/gstvideoscale.c	Thu Dec 17 08:53:32 2009 +0200
@@ -0,0 +1,959 @@
+/* GStreamer
+ * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
+ * Copyright (C) 2005 David Schleef <ds@schleef.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-videoscale
+ * @see_also: videorate, ffmpegcolorspace
+ *
+ * <refsect2>
+ * <para>
+ * This element resizes video frames. By default the element will try to
+ * negotiate to the same size on the source and sinkpad so that no scaling
+ * is needed. It is therefore safe to insert this element in a pipeline to
+ * get more robust behaviour without any cost if no scaling is needed.
+ * </para>
+ * <para>
+ * This element supports a wide range of color spaces including various YUV and
+ * RGB formats and is therefore generally able to operate anywhere in a
+ * pipeline.
+ * </para>
+ * <title>Example pipelines</title>
+ * <para>
+ * <programlisting>
+ * gst-launch -v filesrc location=videotestsrc.ogg ! oggdemux ! theoradec ! ffmpegcolorspace ! videoscale ! ximagesink
+ * </programlisting>
+ * Decode an Ogg/Theora and display the video using ximagesink. Since
+ * ximagesink cannot perform scaling, the video scaling will be performed by
+ * videoscale when you resize the video window.
+ * To create the test Ogg/Theora file refer to the documentation of theoraenc.
+ * </para>
+ * <para>
+ * <programlisting>
+ * gst-launch -v filesrc location=videotestsrc.ogg ! oggdemux ! theoradec ! videoscale ! video/x-raw-yuv, width=50 ! xvimagesink
+ * </programlisting>
+ * Decode an Ogg/Theora and display the video using xvimagesink with a width of
+ * 50.
+ * </para>
+ * </refsect2>
+ *
+ * Last reviewed on 2006-03-02 (0.10.4)
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <string.h>
+
+#include <gst/video/video.h>
+#include <gst/liboil.h>
+
+
+#include "gstvideoscale.h"
+#include "vs_image.h"
+#include "vs_4tap.h"
+
+#include <glib_global.h>
+
+
+/* debug variable definition */
+GST_DEBUG_CATEGORY (video_scale_debug);
+
+/* elementfactory information */
+static const GstElementDetails video_scale_details =
+GST_ELEMENT_DETAILS ("Video scaler",
+    "Filter/Effect/Video",
+    "Resizes video",
+    "Wim Taymans <wim.taymans@chello.be>");
+
+#define DEFAULT_PROP_METHOD	GST_VIDEO_SCALE_NEAREST
+
+enum
+{
+  PROP_0,
+  PROP_METHOD
+      /* FILL ME */
+};
+
+/* can't handle width/height of 1 yet, since we divide a lot by (n-1) */
+#undef GST_VIDEO_SIZE_RANGE
+#define GST_VIDEO_SIZE_RANGE "(int) [ 2, MAX ]"
+
+static GstStaticCaps gst_video_scale_format_caps[] = {
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_RGBx),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_xRGB),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_BGRx),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_xBGR),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_RGBA),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_ARGB),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_BGRA),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_ABGR),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_RGB),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_BGR),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("AYUV")),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("YUY2")),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("YVYU")),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("UYVY")),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("Y800")),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("I420")),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("YV12")),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_RGB_16),
+  GST_STATIC_CAPS (GST_VIDEO_CAPS_RGB_15)
+};
+
+enum
+{
+  GST_VIDEO_SCALE_RGBx = 0,
+  GST_VIDEO_SCALE_xRGB,
+  GST_VIDEO_SCALE_BGRx,
+  GST_VIDEO_SCALE_xBGR,
+  GST_VIDEO_SCALE_RGBA,
+  GST_VIDEO_SCALE_ARGB,
+  GST_VIDEO_SCALE_BGRA,
+  GST_VIDEO_SCALE_ABGR,
+  GST_VIDEO_SCALE_RGB,
+  GST_VIDEO_SCALE_BGR,
+  GST_VIDEO_SCALE_AYUV,
+  GST_VIDEO_SCALE_YUY2,
+  GST_VIDEO_SCALE_YVYU,
+  GST_VIDEO_SCALE_UYVY,
+  GST_VIDEO_SCALE_Y,
+  GST_VIDEO_SCALE_I420,
+  GST_VIDEO_SCALE_YV12,
+  GST_VIDEO_SCALE_RGB565,
+  GST_VIDEO_SCALE_RGB555
+};
+
+#define GST_TYPE_VIDEO_SCALE_METHOD (gst_video_scale_method_get_type())
+static GType
+gst_video_scale_method_get_type (void)
+{
+  static GType video_scale_method_type = 0;
+  static const GEnumValue video_scale_methods[] = {
+    {GST_VIDEO_SCALE_NEAREST, "Nearest Neighbour", "nearest-neighbour"},
+    {GST_VIDEO_SCALE_BILINEAR, "Bilinear", "bilinear"},
+    {GST_VIDEO_SCALE_4TAP, "4-tap", "4-tap"},
+    {0, NULL, NULL},
+  };
+
+  if (!video_scale_method_type) {
+    video_scale_method_type =
+        g_enum_register_static ("GstVideoScaleMethod", video_scale_methods);
+  }
+  return video_scale_method_type;
+}
+
+static GstCaps *
+gst_video_scale_get_capslist (void)
+{
+  static GstCaps *caps;
+
+  if (caps == NULL) {
+    int i;
+
+    caps = gst_caps_new_empty ();
+    for (i = 0; i < G_N_ELEMENTS (gst_video_scale_format_caps); i++)
+      gst_caps_append (caps,
+          gst_caps_make_writable
+          (gst_static_caps_get (&gst_video_scale_format_caps[i])));
+  }
+
+  return caps;
+}
+
+static GstPadTemplate *
+gst_video_scale_src_template_factory (void)
+{
+  return gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
+      gst_caps_ref (gst_video_scale_get_capslist ()));
+}
+
+static GstPadTemplate *
+gst_video_scale_sink_template_factory (void)
+{
+  return gst_pad_template_new ("sink", GST_PAD_SINK, GST_PAD_ALWAYS,
+      gst_caps_ref (gst_video_scale_get_capslist ()));
+}
+
+
+static void gst_video_scale_base_init (gpointer g_class);
+static void gst_video_scale_class_init (GstVideoScaleClass * klass);
+static void gst_video_scale_init (GstVideoScale * videoscale);
+static void gst_video_scale_finalize (GstVideoScale * videoscale);
+static gboolean gst_video_scale_src_event (GstBaseTransform * trans,
+    GstEvent * event);
+
+/* base transform vmethods */
+static GstCaps *gst_video_scale_transform_caps (GstBaseTransform * trans,
+    GstPadDirection direction, GstCaps * caps);
+static gboolean gst_video_scale_set_caps (GstBaseTransform * trans,
+    GstCaps * in, GstCaps * out);
+static gboolean gst_video_scale_get_unit_size (GstBaseTransform * trans,
+    GstCaps * caps, guint * size);
+static GstFlowReturn gst_video_scale_transform (GstBaseTransform * trans,
+    GstBuffer * in, GstBuffer * out);
+static void gst_video_scale_fixate_caps (GstBaseTransform * base,
+    GstPadDirection direction, GstCaps * caps, GstCaps * othercaps);
+
+static void gst_video_scale_set_property (GObject * object, guint prop_id,
+    const GValue * value, GParamSpec * pspec);
+static void gst_video_scale_get_property (GObject * object, guint prop_id,
+    GValue * value, GParamSpec * pspec);
+
+static GstElementClass *parent_class = NULL;
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+
+GType
+gst_video_scale_get_type (void)
+{
+  static GType video_scale_type = 0;
+
+  if (!video_scale_type) {
+    static const GTypeInfo video_scale_info = {
+      sizeof (GstVideoScaleClass),
+      gst_video_scale_base_init,
+      NULL,
+      (GClassInitFunc) gst_video_scale_class_init,
+      NULL,
+      NULL,
+      sizeof (GstVideoScale),
+      0,
+      (GInstanceInitFunc) gst_video_scale_init,
+    };
+
+    video_scale_type =
+        g_type_register_static (GST_TYPE_BASE_TRANSFORM, "GstVideoScale",
+        &video_scale_info, 0);
+  }
+  return video_scale_type;
+}
+
+static void
+gst_video_scale_base_init (gpointer g_class)
+{
+  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
+
+  gst_element_class_set_details (element_class, &video_scale_details);
+
+  gst_element_class_add_pad_template (element_class,
+      gst_video_scale_sink_template_factory ());
+  gst_element_class_add_pad_template (element_class,
+      gst_video_scale_src_template_factory ());
+}
+
+static void
+gst_video_scale_class_init (GstVideoScaleClass * klass)
+{
+  GObjectClass *gobject_class;
+  GstBaseTransformClass *trans_class;
+
+  gobject_class = (GObjectClass *) klass;
+  trans_class = (GstBaseTransformClass *) klass;
+
+  gobject_class->finalize = (GObjectFinalizeFunc) gst_video_scale_finalize;
+  gobject_class->set_property = gst_video_scale_set_property;
+  gobject_class->get_property = gst_video_scale_get_property;
+
+  g_object_class_install_property (gobject_class, PROP_METHOD,
+      g_param_spec_enum ("method", "method", "method",
+          GST_TYPE_VIDEO_SCALE_METHOD, DEFAULT_PROP_METHOD, G_PARAM_READWRITE));
+
+  trans_class->transform_caps =
+      GST_DEBUG_FUNCPTR (gst_video_scale_transform_caps);
+  trans_class->set_caps = GST_DEBUG_FUNCPTR (gst_video_scale_set_caps);
+  trans_class->get_unit_size =
+      GST_DEBUG_FUNCPTR (gst_video_scale_get_unit_size);
+  trans_class->transform = GST_DEBUG_FUNCPTR (gst_video_scale_transform);
+  trans_class->fixate_caps = GST_DEBUG_FUNCPTR (gst_video_scale_fixate_caps);
+  trans_class->src_event = GST_DEBUG_FUNCPTR (gst_video_scale_src_event);
+
+  trans_class->passthrough_on_same_caps = TRUE;
+
+  parent_class = g_type_class_peek_parent (klass);
+}
+
+static void
+gst_video_scale_init (GstVideoScale * videoscale)
+{
+  gst_base_transform_set_qos_enabled (GST_BASE_TRANSFORM (videoscale), TRUE);
+  videoscale->tmp_buf = NULL;
+  videoscale->method = DEFAULT_PROP_METHOD;
+}
+
+static void
+gst_video_scale_finalize (GstVideoScale * videoscale)
+{
+  if (videoscale->tmp_buf)
+    g_free (videoscale->tmp_buf);
+
+  G_OBJECT_CLASS (parent_class)->finalize (G_OBJECT (videoscale));
+}
+
+static void
+gst_video_scale_set_property (GObject * object, guint prop_id,
+    const GValue * value, GParamSpec * pspec)
+{
+  GstVideoScale *vscale = GST_VIDEO_SCALE (object);
+
+  switch (prop_id) {
+    case PROP_METHOD:
+      GST_OBJECT_LOCK (vscale);
+      vscale->method = g_value_get_enum (value);
+      GST_OBJECT_UNLOCK (vscale);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static void
+gst_video_scale_get_property (GObject * object, guint prop_id, GValue * value,
+    GParamSpec * pspec)
+{
+  GstVideoScale *vscale = GST_VIDEO_SCALE (object);
+
+  switch (prop_id) {
+    case PROP_METHOD:
+      GST_OBJECT_LOCK (vscale);
+      g_value_set_enum (value, vscale->method);
+      GST_OBJECT_UNLOCK (vscale);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static GstCaps *
+gst_video_scale_transform_caps (GstBaseTransform * trans,
+    GstPadDirection direction, GstCaps * caps)
+{
+  GstVideoScale *videoscale;
+  GstCaps *ret;
+  GstStructure *structure;
+  const GValue *par;
+  gint method;
+
+  /* this function is always called with a simple caps */
+  g_return_val_if_fail (GST_CAPS_IS_SIMPLE (caps), NULL);
+
+  videoscale = GST_VIDEO_SCALE (trans);
+
+  GST_OBJECT_LOCK (videoscale);
+  method = videoscale->method;
+  GST_OBJECT_UNLOCK (videoscale);
+
+  structure = gst_caps_get_structure (caps, 0);
+
+  /* check compatibility of format and method before we copy the input caps */
+  if (method == GST_VIDEO_SCALE_4TAP) {
+    guint32 fourcc;
+
+    if (!gst_structure_has_name (structure, "video/x-raw-yuv"))
+      goto method_not_implemented_for_format;
+    if (!gst_structure_get_fourcc (structure, "format", &fourcc))
+      goto method_not_implemented_for_format;
+    if (fourcc != GST_MAKE_FOURCC ('I', '4', '2', '0') &&
+        fourcc != GST_MAKE_FOURCC ('Y', 'V', '1', '2'))
+      goto method_not_implemented_for_format;
+  }
+
+  ret = gst_caps_copy (caps);
+  structure = gst_caps_get_structure (ret, 0);
+
+  gst_structure_set (structure,
+      "width", GST_TYPE_INT_RANGE, 1, G_MAXINT,
+      "height", GST_TYPE_INT_RANGE, 1, G_MAXINT, NULL);
+
+  /* if pixel aspect ratio, make a range of it */
+  if ((par = gst_structure_get_value (structure, "pixel-aspect-ratio"))) {
+    GstCaps *copy;
+    GstStructure *cstruct;
+
+    /* copy input PAR first, this is the prefered PAR */
+    gst_structure_set_value (structure, "pixel-aspect-ratio", par);
+
+    /* then make a copy with a fraction range as a second choice */
+    copy = gst_caps_copy (ret);
+    cstruct = gst_caps_get_structure (copy, 0);
+    gst_structure_set (cstruct,
+        "pixel-aspect-ratio", GST_TYPE_FRACTION_RANGE, 0, 1, G_MAXINT, 1, NULL);
+
+    /* and append */
+    gst_caps_append (ret, copy);
+  }
+
+  GST_DEBUG_OBJECT (trans, "returning caps: %" GST_PTR_FORMAT, ret);
+
+  return ret;
+
+method_not_implemented_for_format:
+  {
+    GST_DEBUG_OBJECT (trans, "method %d not implemented for format %"
+        GST_PTR_FORMAT ", returning empty caps", method, caps);
+    return gst_caps_new_empty ();
+  }
+}
+
+static int
+gst_video_scale_get_format (GstCaps * caps)
+{
+  int i;
+  GstCaps *icaps, *scaps;
+
+  for (i = 0; i < G_N_ELEMENTS (gst_video_scale_format_caps); i++) {
+    scaps = gst_static_caps_get (&gst_video_scale_format_caps[i]);
+    icaps = gst_caps_intersect (caps, scaps);
+    if (!gst_caps_is_empty (icaps)) {
+      gst_caps_unref (icaps);
+      return i;
+    }
+    gst_caps_unref (icaps);
+  }
+
+  return -1;
+}
+
+/* calculate the size of a buffer */
+static gboolean
+gst_video_scale_prepare_size (GstVideoScale * videoscale, gint format,
+    VSImage * img, gint width, gint height, guint * size)
+{
+  gboolean res = TRUE;
+
+  img->width = width;
+  img->height = height;
+
+  switch (format) {
+    case GST_VIDEO_SCALE_RGBx:
+    case GST_VIDEO_SCALE_xRGB:
+    case GST_VIDEO_SCALE_BGRx:
+    case GST_VIDEO_SCALE_xBGR:
+    case GST_VIDEO_SCALE_RGBA:
+    case GST_VIDEO_SCALE_ARGB:
+    case GST_VIDEO_SCALE_BGRA:
+    case GST_VIDEO_SCALE_ABGR:
+    case GST_VIDEO_SCALE_AYUV:
+      img->stride = img->width * 4;
+      *size = img->stride * img->height;
+      break;
+    case GST_VIDEO_SCALE_RGB:
+    case GST_VIDEO_SCALE_BGR:
+      img->stride = GST_ROUND_UP_4 (img->width * 3);
+      *size = img->stride * img->height;
+      break;
+    case GST_VIDEO_SCALE_YUY2:
+    case GST_VIDEO_SCALE_YVYU:
+    case GST_VIDEO_SCALE_UYVY:
+      img->stride = GST_ROUND_UP_4 (img->width * 2);
+      *size = img->stride * img->height;
+      break;
+    case GST_VIDEO_SCALE_Y:
+      img->stride = GST_ROUND_UP_4 (img->width);
+      *size = img->stride * img->height;
+      break;
+    case GST_VIDEO_SCALE_I420:
+    case GST_VIDEO_SCALE_YV12:
+    {
+      gulong img_u_stride, img_u_height;
+
+      img->stride = GST_ROUND_UP_4 (img->width);
+
+      img_u_height = GST_ROUND_UP_2 (img->height) / 2;
+      img_u_stride = GST_ROUND_UP_4 (img->stride / 2);
+
+      *size = img->stride * GST_ROUND_UP_2 (img->height) +
+          2 * img_u_stride * img_u_height;
+      break;
+    }
+    case GST_VIDEO_SCALE_RGB565:
+      img->stride = GST_ROUND_UP_4 (img->width * 2);
+      *size = img->stride * img->height;
+      break;
+    case GST_VIDEO_SCALE_RGB555:
+      img->stride = GST_ROUND_UP_4 (img->width * 2);
+      *size = img->stride * img->height;
+      break;
+    default:
+      goto unknown_format;
+  }
+
+  return res;
+
+  /* ERRORS */
+unknown_format:
+  {
+    GST_ELEMENT_ERROR (videoscale, STREAM, NOT_IMPLEMENTED, (NULL),
+        ("Unsupported format %d", videoscale->format));
+    return FALSE;
+  }
+}
+
+static gboolean
+parse_caps (GstCaps * caps, gint * format, gint * width, gint * height)
+{
+  gboolean ret;
+  GstStructure *structure;
+
+  structure = gst_caps_get_structure (caps, 0);
+  ret = gst_structure_get_int (structure, "width", width);
+  ret &= gst_structure_get_int (structure, "height", height);
+
+  if (format)
+    *format = gst_video_scale_get_format (caps);
+
+  return ret;
+}
+
+static gboolean
+gst_video_scale_set_caps (GstBaseTransform * trans, GstCaps * in, GstCaps * out)
+{
+  GstVideoScale *videoscale;
+  gboolean ret;
+
+  videoscale = GST_VIDEO_SCALE (trans);
+
+  ret = parse_caps (in, &videoscale->format, &videoscale->from_width,
+      &videoscale->from_height);
+  ret &= parse_caps (out, NULL, &videoscale->to_width, &videoscale->to_height);
+  if (!ret)
+    goto done;
+
+  if (!(ret = gst_video_scale_prepare_size (videoscale, videoscale->format,
+              &videoscale->src, videoscale->from_width, videoscale->from_height,
+              &videoscale->src_size)))
+    /* prepare size has posted an error when it returns FALSE */
+    goto done;
+
+  if (!(ret = gst_video_scale_prepare_size (videoscale, videoscale->format,
+              &videoscale->dest, videoscale->to_width, videoscale->to_height,
+              &videoscale->dest_size)))
+    /* prepare size has posted an error when it returns FALSE */
+    goto done;
+
+  if (videoscale->tmp_buf)
+    g_free (videoscale->tmp_buf);
+
+  videoscale->tmp_buf = g_malloc (videoscale->dest.stride * 4);
+
+  /* FIXME: par */
+  GST_DEBUG_OBJECT (videoscale, "from=%dx%d, size %d -> to=%dx%d, size %d",
+      videoscale->from_width, videoscale->from_height, videoscale->src_size,
+      videoscale->to_width, videoscale->to_height, videoscale->dest_size);
+
+done:
+  return ret;
+}
+
+static gboolean
+gst_video_scale_get_unit_size (GstBaseTransform * trans, GstCaps * caps,
+    guint * size)
+{
+  GstVideoScale *videoscale;
+  gint format, width, height;
+  VSImage img;
+
+  g_assert (size);
+
+  videoscale = GST_VIDEO_SCALE (trans);
+
+  if (!parse_caps (caps, &format, &width, &height))
+    return FALSE;
+
+  if (!gst_video_scale_prepare_size (videoscale, format, &img, width, height,
+          size))
+    return FALSE;
+
+  return TRUE;
+}
+
+static void
+gst_video_scale_fixate_caps (GstBaseTransform * base, GstPadDirection direction,
+    GstCaps * caps, GstCaps * othercaps)
+{
+  GstStructure *ins, *outs;
+  const GValue *from_par, *to_par;
+
+  g_return_if_fail (gst_caps_is_fixed (caps));
+
+  GST_DEBUG_OBJECT (base, "trying to fixate othercaps %" GST_PTR_FORMAT
+      " based on caps %" GST_PTR_FORMAT, othercaps, caps);
+
+  ins = gst_caps_get_structure (caps, 0);
+  outs = gst_caps_get_structure (othercaps, 0);
+
+  from_par = gst_structure_get_value (ins, "pixel-aspect-ratio");
+  to_par = gst_structure_get_value (outs, "pixel-aspect-ratio");
+
+  /* we have both PAR but they might not be fixated */
+  if (from_par && to_par) {
+    gint from_w, from_h, from_par_n, from_par_d, to_par_n, to_par_d;
+    gint count = 0, w = 0, h = 0;
+    guint num, den;
+
+    /* from_par should be fixed */
+    g_return_if_fail (gst_value_is_fixed (from_par));
+
+    from_par_n = gst_value_get_fraction_numerator (from_par);
+    from_par_d = gst_value_get_fraction_denominator (from_par);
+
+    /* fixate the out PAR */
+    if (!gst_value_is_fixed (to_par)) {
+      GST_DEBUG_OBJECT (base, "fixating to_par to %dx%d", from_par_n,
+          from_par_d);
+      gst_structure_fixate_field_nearest_fraction (outs, "pixel-aspect-ratio",
+          from_par_n, from_par_d);
+    }
+
+    to_par_n = gst_value_get_fraction_numerator (to_par);
+    to_par_d = gst_value_get_fraction_denominator (to_par);
+
+    /* if both width and height are already fixed, we can't do anything
+     * about it anymore */
+    if (gst_structure_get_int (outs, "width", &w))
+      ++count;
+    if (gst_structure_get_int (outs, "height", &h))
+      ++count;
+    if (count == 2) {
+      GST_DEBUG_OBJECT (base, "dimensions already set to %dx%d, not fixating",
+          w, h);
+      return;
+    }
+
+    gst_structure_get_int (ins, "width", &from_w);
+    gst_structure_get_int (ins, "height", &from_h);
+
+    if (!gst_video_calculate_display_ratio (&num, &den, from_w, from_h,
+            from_par_n, from_par_d, to_par_n, to_par_d)) {
+      GST_ELEMENT_ERROR (base, CORE, NEGOTIATION, (NULL),
+          ("Error calculating the output scaled size - integer overflow"));
+      return;
+    }
+
+    GST_DEBUG_OBJECT (base,
+        "scaling input with %dx%d and PAR %d/%d to output PAR %d/%d",
+        from_w, from_h, from_par_n, from_par_d, to_par_n, to_par_d);
+    GST_DEBUG_OBJECT (base, "resulting output should respect ratio of %d/%d",
+        num, den);
+
+    /* now find a width x height that respects this display ratio.
+     * prefer those that have one of w/h the same as the incoming video
+     * using wd / hd = num / den */
+
+    /* if one of the output width or height is fixed, we work from there */
+    if (h) {
+      GST_DEBUG_OBJECT (base, "height is fixed,scaling width");
+      w = (guint) gst_util_uint64_scale_int (h, num, den);
+    } else if (w) {
+      GST_DEBUG_OBJECT (base, "width is fixed, scaling height");
+      h = (guint) gst_util_uint64_scale_int (w, den, num);
+    } else {
+      /* none of width or height is fixed, figure out both of them based only on
+       * the input width and height */
+      /* check hd / den is an integer scale factor, and scale wd with the PAR */
+      if (from_h % den == 0) {
+        GST_DEBUG_OBJECT (base, "keeping video height");
+        h = from_h;
+        w = (guint) gst_util_uint64_scale_int (h, num, den);
+      } else if (from_w % num == 0) {
+        GST_DEBUG_OBJECT (base, "keeping video width");
+        w = from_w;
+        h = (guint) gst_util_uint64_scale_int (w, den, num);
+      } else {
+        GST_DEBUG_OBJECT (base, "approximating but keeping video height");
+        h = from_h;
+        w = (guint) gst_util_uint64_scale_int (h, num, den);
+      }
+    }
+    GST_DEBUG_OBJECT (base, "scaling to %dx%d", w, h);
+
+    /* now fixate */
+    gst_structure_fixate_field_nearest_int (outs, "width", w);
+    gst_structure_fixate_field_nearest_int (outs, "height", h);
+  } else {
+    gint width, height;
+
+    if (gst_structure_get_int (ins, "width", &width)) {
+      if (gst_structure_has_field (outs, "width")) {
+        gst_structure_fixate_field_nearest_int (outs, "width", width);
+      }
+    }
+    if (gst_structure_get_int (ins, "height", &height)) {
+      if (gst_structure_has_field (outs, "height")) {
+        gst_structure_fixate_field_nearest_int (outs, "height", height);
+      }
+    }
+  }
+
+  GST_DEBUG_OBJECT (base, "fixated othercaps to %" GST_PTR_FORMAT, othercaps);
+}
+
+static gboolean
+gst_video_scale_prepare_image (gint format, GstBuffer * buf,
+    VSImage * img, VSImage * img_u, VSImage * img_v)
+{
+  gboolean res = TRUE;
+
+  img->pixels = GST_BUFFER_DATA (buf);
+
+  switch (format) {
+    case GST_VIDEO_SCALE_I420:
+    case GST_VIDEO_SCALE_YV12:
+      img_u->pixels = img->pixels + GST_ROUND_UP_2 (img->height) * img->stride;
+      img_u->height = GST_ROUND_UP_2 (img->height) / 2;
+      img_u->width = GST_ROUND_UP_2 (img->width) / 2;
+      img_u->stride = GST_ROUND_UP_4 (img_u->width);
+      memcpy (img_v, img_u, sizeof (*img_v));
+      img_v->pixels = img_u->pixels + img_u->height * img_u->stride;
+      break;
+    default:
+      break;
+  }
+  return res;
+}
+
+static GstFlowReturn
+gst_video_scale_transform (GstBaseTransform * trans, GstBuffer * in,
+    GstBuffer * out)
+{
+  GstVideoScale *videoscale;
+  GstFlowReturn ret = GST_FLOW_OK;
+  VSImage *dest;
+  VSImage *src;
+  VSImage dest_u;
+  VSImage dest_v;
+  VSImage src_u;
+  VSImage src_v;
+  gint method;
+
+  videoscale = GST_VIDEO_SCALE (trans);
+
+  GST_OBJECT_LOCK (videoscale);
+  method = videoscale->method;
+  GST_OBJECT_UNLOCK (videoscale);
+
+  src = &videoscale->src;
+  dest = &videoscale->dest;
+
+  gst_video_scale_prepare_image (videoscale->format, in, src, &src_u, &src_v);
+  gst_video_scale_prepare_image (videoscale->format, out, dest, &dest_u,
+      &dest_v);
+
+  switch (method) {
+    case GST_VIDEO_SCALE_NEAREST:
+      switch (videoscale->format) {
+        case GST_VIDEO_SCALE_RGBx:
+        case GST_VIDEO_SCALE_xRGB:
+        case GST_VIDEO_SCALE_BGRx:
+        case GST_VIDEO_SCALE_xBGR:
+        case GST_VIDEO_SCALE_RGBA:
+        case GST_VIDEO_SCALE_ARGB:
+        case GST_VIDEO_SCALE_BGRA:
+        case GST_VIDEO_SCALE_ABGR:
+        case GST_VIDEO_SCALE_AYUV:
+          vs_image_scale_nearest_RGBA (dest, src, videoscale->tmp_buf);
+          break;
+        case GST_VIDEO_SCALE_RGB:
+        case GST_VIDEO_SCALE_BGR:
+          vs_image_scale_nearest_RGB (dest, src, videoscale->tmp_buf);
+          break;
+        case GST_VIDEO_SCALE_YUY2:
+        case GST_VIDEO_SCALE_YVYU:
+          vs_image_scale_nearest_YUYV (dest, src, videoscale->tmp_buf);
+          break;
+        case GST_VIDEO_SCALE_UYVY:
+          vs_image_scale_nearest_UYVY (dest, src, videoscale->tmp_buf);
+          break;
+        case GST_VIDEO_SCALE_Y:
+          vs_image_scale_nearest_Y (dest, src, videoscale->tmp_buf);
+          break;
+        case GST_VIDEO_SCALE_I420:
+        case GST_VIDEO_SCALE_YV12:
+          vs_image_scale_nearest_Y (dest, src, videoscale->tmp_buf);
+          vs_image_scale_nearest_Y (&dest_u, &src_u, videoscale->tmp_buf);
+          vs_image_scale_nearest_Y (&dest_v, &src_v, videoscale->tmp_buf);
+          break;
+        case GST_VIDEO_SCALE_RGB565:
+          vs_image_scale_nearest_RGB565 (dest, src, videoscale->tmp_buf);
+          break;
+        case GST_VIDEO_SCALE_RGB555:
+          vs_image_scale_nearest_RGB555 (dest, src, videoscale->tmp_buf);
+          break;
+        default:
+          goto unsupported;
+      }
+      break;
+    case GST_VIDEO_SCALE_BILINEAR:
+      switch (videoscale->format) {
+        case GST_VIDEO_SCALE_RGBx:
+        case GST_VIDEO_SCALE_xRGB:
+        case GST_VIDEO_SCALE_BGRx:
+        case GST_VIDEO_SCALE_xBGR:
+        case GST_VIDEO_SCALE_RGBA:
+        case GST_VIDEO_SCALE_ARGB:
+        case GST_VIDEO_SCALE_BGRA:
+        case GST_VIDEO_SCALE_ABGR:
+        case GST_VIDEO_SCALE_AYUV:
+          vs_image_scale_linear_RGBA (dest, src, videoscale->tmp_buf);
+          break;
+        case GST_VIDEO_SCALE_RGB:
+        case GST_VIDEO_SCALE_BGR:
+          vs_image_scale_linear_RGB (dest, src, videoscale->tmp_buf);
+          break;
+        case GST_VIDEO_SCALE_YUY2:
+        case GST_VIDEO_SCALE_YVYU:
+          vs_image_scale_linear_YUYV (dest, src, videoscale->tmp_buf);
+          break;
+        case GST_VIDEO_SCALE_UYVY:
+          vs_image_scale_linear_UYVY (dest, src, videoscale->tmp_buf);
+          break;
+        case GST_VIDEO_SCALE_Y:
+          vs_image_scale_linear_Y (dest, src, videoscale->tmp_buf);
+          break;
+        case GST_VIDEO_SCALE_I420:
+        case GST_VIDEO_SCALE_YV12:
+          vs_image_scale_linear_Y (dest, src, videoscale->tmp_buf);
+          vs_image_scale_linear_Y (&dest_u, &src_u, videoscale->tmp_buf);
+          vs_image_scale_linear_Y (&dest_v, &src_v, videoscale->tmp_buf);
+          break;
+        case GST_VIDEO_SCALE_RGB565:
+          vs_image_scale_linear_RGB565 (dest, src, videoscale->tmp_buf);
+          break;
+        case GST_VIDEO_SCALE_RGB555:
+          vs_image_scale_linear_RGB555 (dest, src, videoscale->tmp_buf);
+          break;
+        default:
+          goto unsupported;
+      }
+      break;
+    case GST_VIDEO_SCALE_4TAP:
+      switch (videoscale->format) {
+        case GST_VIDEO_SCALE_I420:
+        case GST_VIDEO_SCALE_YV12:
+          vs_image_scale_4tap_Y (dest, src, videoscale->tmp_buf);
+          vs_image_scale_4tap_Y (&dest_u, &src_u, videoscale->tmp_buf);
+          vs_image_scale_4tap_Y (&dest_v, &src_v, videoscale->tmp_buf);
+          break;
+        default:
+          /* FIXME: update gst_video_scale_transform_caps once RGB and/or
+           * other YUV formats work too */
+          goto unsupported;
+      }
+      break;
+    default:
+      goto unknown_mode;
+  }
+
+  GST_LOG_OBJECT (videoscale, "pushing buffer of %d bytes",
+      GST_BUFFER_SIZE (out));
+
+  return ret;
+
+  /* ERRORS */
+unsupported:
+  {
+    GST_ELEMENT_ERROR (videoscale, STREAM, NOT_IMPLEMENTED, (NULL),
+        ("Unsupported format %d for scaling method %d",
+            videoscale->format, method));
+    return GST_FLOW_ERROR;
+  }
+unknown_mode:
+  {
+    GST_ELEMENT_ERROR (videoscale, STREAM, NOT_IMPLEMENTED, (NULL),
+        ("Unknown scaling method %d", videoscale->method));
+    return GST_FLOW_ERROR;
+  }
+}
+
+static gboolean
+gst_video_scale_src_event (GstBaseTransform * trans, GstEvent * event)
+{
+  GstVideoScale *videoscale;
+  gboolean ret;
+  double a;
+  GstStructure *structure;
+
+  videoscale = GST_VIDEO_SCALE (trans);
+
+  GST_DEBUG_OBJECT (videoscale, "handling %s event",
+      GST_EVENT_TYPE_NAME (event));
+
+  switch (GST_EVENT_TYPE (event)) {
+    case GST_EVENT_NAVIGATION:
+      event =
+          GST_EVENT (gst_mini_object_make_writable (GST_MINI_OBJECT (event)));
+
+      structure = (GstStructure *) gst_event_get_structure (event);
+      if (gst_structure_get_double (structure, "pointer_x", &a)) {
+        gst_structure_set (structure, "pointer_x", G_TYPE_DOUBLE,
+            a * videoscale->from_width / videoscale->to_width, NULL);
+      }
+      if (gst_structure_get_double (structure, "pointer_y", &a)) {
+        gst_structure_set (structure, "pointer_y", G_TYPE_DOUBLE,
+            a * videoscale->from_height / videoscale->to_height, NULL);
+      }
+      break;
+    case GST_EVENT_QOS:
+      break;
+    default:
+      break;
+  }
+
+  ret = GST_BASE_TRANSFORM_CLASS (parent_class)->src_event (trans, event);
+
+  return ret;
+}
+
+static gboolean
+plugin_init (GstPlugin * plugin)
+{
+	#ifndef __SYMBIAN32__
+  oil_init ();
+  #endif
+  if (!gst_element_register (plugin, "videoscale", GST_RANK_NONE,
+          GST_TYPE_VIDEO_SCALE))
+    return FALSE;
+
+  GST_DEBUG_CATEGORY_INIT (video_scale_debug, "videoscale", 0,
+      "videoscale element");
+
+  vs_4tap_init ();
+
+  return TRUE;
+}
+
+GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
+    GST_VERSION_MINOR,
+    "videoscale",
+    "Resizes video", plugin_init, VERSION, GST_LICENSE, GST_PACKAGE_NAME,
+    GST_PACKAGE_ORIGIN);
+    
+#ifdef __SYMBIAN32__
+EXPORT_C 
+#endif
+GstPluginDesc* _GST_PLUGIN_DESC()
+{
+	return &gst_plugin_desc;
+}