1 files changed, 99 insertions, 0 deletions
diff --git a/gst/dvdspu/gstdvdspu-render.c b/gst/dvdspu/gstdvdspu-render.c
new file mode 100644
index 000000000..9c34270ca
--- /dev/null
+++ b/gst/dvdspu/gstdvdspu-render.c
@@ -0,0 +1,99 @@
+/* GStreamer DVD Sub-Picture Unit
+ * Copyright (C) 2007 Fluendo S.A. <info@fluendo.com>
+ * Copyright (C) 2009 Jan Schmidt <thaytan@noraisin.net>
+ *
+ * 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.
+ */
+#ifdef HAVE_CONFIG_H
+#  include <config.h>
+#endif
+
+#include <string.h>
+
+#include <gst/gst.h>
+
+#include "gstdvdspu.h"
+
+GST_DEBUG_CATEGORY_EXTERN (dvdspu_debug);
+#define GST_CAT_DEFAULT dvdspu_debug
+
+void
+gstspu_clear_comp_buffers (SpuState * state)
+{
+  /* The area to clear is the line inside the disp_rect, each entry 4 bytes,
+   * of the sub-sampled UV planes. */
+  gint16 left = state->comp_left / 2;
+  gint16 right = state->comp_right / 2;
+  gint16 uv_width = sizeof (guint32) * (right - left + 1);
+
+  memset (state->comp_bufs[0] + left, 0, uv_width);
+  memset (state->comp_bufs[1] + left, 0, uv_width);
+  memset (state->comp_bufs[2] + left, 0, uv_width);
+}
+
+void
+gstspu_blend_comp_buffers (SpuState * state, guint8 * planes[3])
+{
+  gint16 uv_end;
+  gint16 left, x;
+  guint8 *out_U;
+  guint8 *out_V;
+  guint32 *in_U;
+  guint32 *in_V;
+  guint32 *in_A;
+  gint16 comp_last_x = state->comp_right;
+
+  if (comp_last_x < state->comp_left)
+    return;                     /* Didn't draw in the comp buffers, nothing to do... */
+
+#if 0
+  GST_LOG ("Blending comp buffers from x=%d to x=%d",
+      state->comp_left, state->comp_right);
+#endif
+
+  /* Set up the output pointers */
+  out_U = planes[1];            /* U plane */
+  out_V = planes[2];            /* V plane */
+
+  /* Input starts at the first pixel of the compositing buffer */
+  in_U = state->comp_bufs[0];   /* U comp buffer */
+  in_V = state->comp_bufs[1];   /* V comp buffer */
+  in_A = state->comp_bufs[2];   /* A comp buffer */
+
+  /* Calculate how many pixels to blend based on the maximum X value that was 
+   * drawn in the render_line function, divided by 2 (rounding up) to account 
+   * for UV sub-sampling */
+  uv_end = (comp_last_x + 1) / 2;
+  left = state->comp_left / 2;
+
+  out_U += left * GST_VIDEO_INFO_COMP_PSTRIDE (&state->info, 1);
+  out_V += left * GST_VIDEO_INFO_COMP_PSTRIDE (&state->info, 2);
+  for (x = left; x < uv_end; x++) {
+    guint32 tmp;
+    /* Each entry in the compositing buffer is 4 summed pixels, so the
+     * inverse alpha is (4 * 0xff) - in_A[x] */
+    guint16 inv_A = (4 * 0xff) - in_A[x];
+
+    tmp = in_U[x] + inv_A * *out_U;
+    *out_U = (guint8) (tmp / (4 * 0xff));
+
+    tmp = in_V[x] + inv_A * *out_V;
+    *out_V = (guint8) (tmp / (4 * 0xff));
+
+    out_U += GST_VIDEO_INFO_COMP_PSTRIDE (&state->info, 1);
+    out_V += GST_VIDEO_INFO_COMP_PSTRIDE (&state->info, 2);
+  }
+}