Major cleanup of code. Convert glupload to BaseTransform.

Original commit message from CVS:
* configure.ac:
* sys/glsink/glextensions.c:
* sys/glsink/glextensions.h:
* sys/glsink/glimagesink.c:
* sys/glsink/glimagesink.h:
* sys/glsink/gstglbuffer.c:
* sys/glsink/gstglbuffer.h:
* sys/glsink/gstglconvert.c:
* sys/glsink/gstgldisplay.c:
* sys/glsink/gstgldisplay.h:
* sys/glsink/gstgldownload.c:
* sys/glsink/gstglfilter.c:
* sys/glsink/gstglfilter.h:
* sys/glsink/gstglfilterexample.c:
* sys/glsink/gstgltestsrc.c:
* sys/glsink/gstglupload.c:
Major cleanup of code.  Convert glupload to BaseTransform.
Handle caps negotiation mostly correctly.  Reenable in build.

15 files changed, 629 insertions, 412 deletions

diff --git a/sys/glsink/glextensions.c b/sys/glsink/glextensions.c
index 6926a970..ccf55726 100644
--- a/sys/glsink/glextensions.c
+++ b/sys/glsink/glextensions.c
@@ -49,6 +49,7 @@ DEFINE_FUNC_RET (glCreateShaderObjectARB, GLhandleARB,
     (GLenum shaderType), (shaderType));
 #if 0
 typedef GLhandleARB type_glCreateShaderObjectARB (GLenum shaderType);
+
 GLhandleARB
 glCreateShaderObjectARB (GLenum shaderType)
 {
@@ -181,3 +182,8 @@ DEFINE_FUNC (glGetFramebufferAttachmentParameterivEXT, (GLenum target,
 DEFINE_FUNC (glGenerateMipmapEXT, (GLenum target), (target));
 
 DEFINE_FUNC (glWindowPos2iARB, (GLint x, GLint y), (x, y));
+
+DEFINE_FUNC (glGenProgramsARB, (GLsizei a, GLuint * b), (a, b));
+DEFINE_FUNC (glBindProgramARB, (GLenum a, GLuint b), (a, b));
+DEFINE_FUNC (glProgramStringARB,
+    (GLenum a, GLenum b, GLsizei c, const GLvoid * d), (a, b, c, d));
diff --git a/sys/glsink/glextensions.h b/sys/glsink/glextensions.h
index 7ef01869..e161b8c4 100644
--- a/sys/glsink/glextensions.h
+++ b/sys/glsink/glextensions.h
@@ -56,5 +56,9 @@ void glGenerateMipmapEXT (GLenum target);
 
 void glWindowPos2iARB (GLint x, GLint y);
 
+void glGenProgramsARB (GLsizei, GLuint *);
+void glBindProgramARB (GLenum, GLuint);
+void glProgramStringARB (GLenum, GLenum, GLsizei, const GLvoid *);
+
 #endif
 
diff --git a/sys/glsink/glimagesink.c b/sys/glsink/glimagesink.c
index 879790d7..365e4c4e 100644
--- a/sys/glsink/glimagesink.c
+++ b/sys/glsink/glimagesink.c
@@ -301,11 +301,11 @@ gst_glimage_sink_start (GstBaseSink * bsink)
     GST_ERROR ("failed to open display");
     return FALSE;
   }
+#endif
 
-  if (glimage_sink->window_id) {
+  if (glimage_sink->display && glimage_sink->window_id) {
     gst_gl_display_set_window (glimage_sink->display, glimage_sink->window_id);
   }
-#endif
 
   GST_DEBUG ("start done");
 
@@ -321,9 +321,10 @@ gst_glimage_sink_stop (GstBaseSink * bsink)
 
   glimage_sink = GST_GLIMAGE_SINK (bsink);
 
-  g_object_unref (glimage_sink->display);
-
-  glimage_sink->display = NULL;
+  if (glimage_sink->display) {
+    g_object_unref (glimage_sink->display);
+    glimage_sink->display = NULL;
+  }
 
   return TRUE;
 }
@@ -417,14 +418,6 @@ gst_glimage_sink_set_caps (GstBaseSink * bsink, GstCaps * caps)
   glimage_sink->par_n = par_n;
   glimage_sink->par_d = par_d;
 
-  //glimage_sink->type = format;
-
-#if 0
-  if (!glimage_sink->window) {
-    gst_glimage_sink_create_window (glimage_sink);
-  }
-#endif
-
   return TRUE;
 }
 
@@ -441,21 +434,23 @@ gst_glimage_sink_render (GstBaseSink * bsink, GstBuffer * buf)
 
   if (glimage_sink->display == NULL) {
     glimage_sink->display = g_object_ref (gl_buffer->display);
+#if 1
     if (glimage_sink->window_id) {
       gst_gl_display_set_window (glimage_sink->display,
           glimage_sink->window_id);
     }
+#endif
   } else {
     g_assert (gl_buffer->display == glimage_sink->display);
   }
 
   display = gl_buffer->display;
 
-  gst_gl_display_lock (display);
-
   /* FIXME polling causes a round-trip delay.  This should be changed
    * to catch structure events */
   gst_gl_display_update_attributes (display);
+
+  gst_gl_display_lock (display);
   glViewport (0, 0, display->win_width, display->win_height);
 
   glClearColor (0.3, 0.3, 0.3, 1.0);
@@ -519,7 +514,7 @@ gst_glimage_sink_set_xwindow_id (GstXOverlay * overlay, XID window_id)
 
   g_return_if_fail (GST_IS_GLIMAGE_SINK (overlay));
 
-  GST_DEBUG ("set_xwindow_id");
+  GST_DEBUG ("set_xwindow_id %ld", window_id);
 
   glimage_sink = GST_GLIMAGE_SINK (overlay);
 
diff --git a/sys/glsink/glimagesink.h b/sys/glsink/glimagesink.h
index 3467c619..3a5effe9 100644
--- a/sys/glsink/glimagesink.h
+++ b/sys/glsink/glimagesink.h
@@ -58,7 +58,6 @@ struct _GstGLImageSink
   int par_n, par_d;
 
   GstGLDisplay *display;
-  GstVideoFormat type;
 
   XID window_id;
 };
diff --git a/sys/glsink/gstglbuffer.c b/sys/glsink/gstglbuffer.c
index 7a217a36..c1d5bb7b 100644
--- a/sys/glsink/gstglbuffer.c
+++ b/sys/glsink/gstglbuffer.c
@@ -77,11 +77,24 @@ gst_gl_buffer_get_type (void)
 
 
 GstGLBuffer *
-gst_gl_buffer_new (GstGLDisplay * display, GstGLBufferFormat format,
-    int width, int height)
+gst_gl_buffer_new (GstGLDisplay * display, int width, int height)
+{
+  g_return_val_if_fail (display != NULL, NULL);
+  g_return_val_if_fail (width > 0, NULL);
+  g_return_val_if_fail (height > 0, NULL);
+
+  return gst_gl_buffer_new_with_format (display, GST_GL_BUFFER_FORMAT_RGBA,
+      width, height);
+}
+
+GstGLBuffer *
+gst_gl_buffer_new_with_format (GstGLDisplay * display,
+    GstGLBufferFormat format, int width, int height)
 {
   GstGLBuffer *buffer;
 
+  g_return_val_if_fail (format != GST_GL_BUFFER_FORMAT_UNKNOWN, NULL);
+  g_return_val_if_fail (display != NULL, NULL);
   g_return_val_if_fail (width > 0, NULL);
   g_return_val_if_fail (height > 0, NULL);
 
@@ -90,9 +103,9 @@ gst_gl_buffer_new (GstGLDisplay * display, GstGLBufferFormat format,
   buffer->display = g_object_ref (display);
   buffer->width = width;
   buffer->height = height;
-  /* this is not strictly true, but it's used for compatibility with
-   * queue and BaseTransform */
-  GST_BUFFER_SIZE (buffer) = width * height * 4;
+  buffer->format = format;
+  GST_BUFFER_SIZE (buffer) = gst_gl_buffer_format_get_size (format, width,
+      height);
 
   gst_gl_display_lock (buffer->display);
   glGenTextures (1, &buffer->texture);
@@ -100,11 +113,69 @@ gst_gl_buffer_new (GstGLDisplay * display, GstGLBufferFormat format,
   switch (format) {
     case GST_GL_BUFFER_FORMAT_RGBA:
       glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_RGBA,
-          buffer->width, buffer->height, 0, GL_RGBA, GL_FLOAT, NULL);
+          buffer->width, buffer->height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
       break;
     case GST_GL_BUFFER_FORMAT_RGB:
       glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_RGB,
-          buffer->width, buffer->height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
+          buffer->width, buffer->height, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL);
+      break;
+    case GST_GL_BUFFER_FORMAT_YUYV:
+      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_YCBCR_MESA,
+          buffer->width, buffer->height,
+          0, GL_YCBCR_MESA, GL_UNSIGNED_SHORT_8_8_REV_MESA, NULL);
+      break;
+    case GST_GL_BUFFER_FORMAT_PLANAR444:
+      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_LUMINANCE,
+          buffer->width, buffer->height,
+          0, GL_LUMINANCE, GL_UNSIGNED_BYTE, NULL);
+
+      glGenTextures (1, &buffer->texture_u);
+      glBindTexture (GL_TEXTURE_RECTANGLE_ARB, buffer->texture_u);
+      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_LUMINANCE,
+          buffer->width, buffer->height,
+          0, GL_LUMINANCE, GL_UNSIGNED_BYTE, NULL);
+
+      glGenTextures (1, &buffer->texture_v);
+      glBindTexture (GL_TEXTURE_RECTANGLE_ARB, buffer->texture_v);
+      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_LUMINANCE,
+          buffer->width, buffer->height,
+          0, GL_LUMINANCE, GL_UNSIGNED_BYTE, NULL);
+      break;
+    case GST_GL_BUFFER_FORMAT_PLANAR422:
+      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_LUMINANCE,
+          buffer->width, buffer->height,
+          0, GL_LUMINANCE, GL_UNSIGNED_BYTE, NULL);
+
+      glGenTextures (1, &buffer->texture_u);
+      glBindTexture (GL_TEXTURE_RECTANGLE_ARB, buffer->texture_u);
+      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_LUMINANCE,
+          GST_ROUND_UP_2 (buffer->width) / 2, buffer->height,
+          0, GL_LUMINANCE, GL_UNSIGNED_BYTE, NULL);
+
+      glGenTextures (1, &buffer->texture_v);
+      glBindTexture (GL_TEXTURE_RECTANGLE_ARB, buffer->texture_v);
+      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_LUMINANCE,
+          GST_ROUND_UP_2 (buffer->width) / 2, buffer->height,
+          0, GL_LUMINANCE, GL_UNSIGNED_BYTE, NULL);
+      break;
+    case GST_GL_BUFFER_FORMAT_PLANAR420:
+      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_LUMINANCE,
+          buffer->width, buffer->height,
+          0, GL_LUMINANCE, GL_UNSIGNED_BYTE, NULL);
+
+      glGenTextures (1, &buffer->texture_u);
+      glBindTexture (GL_TEXTURE_RECTANGLE_ARB, buffer->texture_u);
+      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_LUMINANCE,
+          GST_ROUND_UP_2 (buffer->width) / 2,
+          GST_ROUND_UP_2 (buffer->height) / 2,
+          0, GL_LUMINANCE, GL_UNSIGNED_BYTE, NULL);
+
+      glGenTextures (1, &buffer->texture_v);
+      glBindTexture (GL_TEXTURE_RECTANGLE_ARB, buffer->texture_v);
+      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_LUMINANCE,
+          GST_ROUND_UP_2 (buffer->width) / 2,
+          GST_ROUND_UP_2 (buffer->height) / 2,
+          0, GL_LUMINANCE, GL_UNSIGNED_BYTE, NULL);
       break;
     default:
       g_warning ("GL buffer format not handled");
@@ -116,138 +187,135 @@ gst_gl_buffer_new (GstGLDisplay * display, GstGLBufferFormat format,
 }
 
 GstGLBuffer *
-gst_gl_buffer_new_from_data (GstGLDisplay * display, GstVideoFormat format,
-    int width, int height, void *data)
+gst_gl_buffer_new_from_video_format (GstGLDisplay * display,
+    GstVideoFormat video_format, int width, int height)
 {
   GstGLBuffer *buffer;
-  int comp;
 
   g_return_val_if_fail (width > 0, NULL);
   g_return_val_if_fail (height > 0, NULL);
-  g_return_val_if_fail (data != NULL, NULL);
+
+  buffer = gst_gl_buffer_new_with_format (display,
+      gst_gl_buffer_format_from_video_format (video_format), width, height);
+
+  switch (video_format) {
+    case GST_VIDEO_FORMAT_RGBx:
+    case GST_VIDEO_FORMAT_BGRx:
+    case GST_VIDEO_FORMAT_xRGB:
+    case GST_VIDEO_FORMAT_xBGR:
+      buffer->is_yuv = FALSE;
+      break;
+    case GST_VIDEO_FORMAT_YUY2:
+    case GST_VIDEO_FORMAT_UYVY:
+      /* counterintuitive: when you use a GL_YCBCR_MESA texture, the
+       * colorspace is automatically converted, so it's referred to
+       * as RGB */
+      buffer->is_yuv = FALSE;
+      break;
+    case GST_VIDEO_FORMAT_AYUV:
+    case GST_VIDEO_FORMAT_I420:
+    case GST_VIDEO_FORMAT_YV12:
+      buffer->is_yuv = TRUE;
+      break;
+    default:
+      g_assert_not_reached ();
+  }
+
+  return buffer;
+}
+
+void
+gst_gl_buffer_upload (GstGLBuffer * buffer, GstVideoFormat video_format,
+    void *data)
+{
+  int width = buffer->width;
+  int height = buffer->height;
 
   GST_DEBUG ("uploading %p %dx%d", data, width, height);
 
-  buffer = (GstGLBuffer *) gst_mini_object_new (GST_TYPE_GL_BUFFER);
-  buffer->display = g_object_ref (display);
-  buffer->width = width;
-  buffer->height = height;
-  /* this is not strictly true, but it's used for compatibility with
-   * queue and BaseTransform */
-  GST_BUFFER_SIZE (buffer) = width * height * 4;
+  g_return_if_fail (buffer->format ==
+      gst_gl_buffer_format_from_video_format (video_format));
 
   gst_gl_display_lock (buffer->display);
-  glGenTextures (1, &buffer->texture);
   glBindTexture (GL_TEXTURE_RECTANGLE_ARB, buffer->texture);
 
-  switch (format) {
+  switch (video_format) {
     case GST_VIDEO_FORMAT_RGBx:
-      buffer->format = GST_GL_BUFFER_FORMAT_RGB;
-      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_RGBA,
-          buffer->width, buffer->height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
       glTexSubImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, 0, 0, width, height,
           GL_RGBA, GL_UNSIGNED_BYTE, data);
       break;
     case GST_VIDEO_FORMAT_BGRx:
-      buffer->format = GST_GL_BUFFER_FORMAT_RGB;
-      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_RGBA,
-          buffer->width, buffer->height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
       glTexSubImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, 0, 0, width, height,
           GL_BGRA, GL_UNSIGNED_BYTE, data);
       break;
+    case GST_VIDEO_FORMAT_AYUV:
     case GST_VIDEO_FORMAT_xRGB:
-      buffer->format = GST_GL_BUFFER_FORMAT_RGB;
-      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_RGBA,
-          buffer->width, buffer->height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
       glTexSubImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, 0, 0, width, height,
           GL_BGRA, GL_UNSIGNED_INT_8_8_8_8, data);
       break;
     case GST_VIDEO_FORMAT_xBGR:
-      buffer->format = GST_GL_BUFFER_FORMAT_RGB;
-      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_RGBA,
-          buffer->width, buffer->height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
       glTexSubImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, 0, 0, width, height,
           GL_RGBA, GL_UNSIGNED_INT_8_8_8_8, data);
       break;
     case GST_VIDEO_FORMAT_YUY2:
-      buffer->format = GST_GL_BUFFER_FORMAT_YUYV;
-      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_YCBCR_MESA, width, height,
-          0, GL_YCBCR_MESA, GL_UNSIGNED_SHORT_8_8_REV_MESA, NULL);
       glTexSubImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, 0, 0, width, height,
           GL_YCBCR_MESA, GL_UNSIGNED_SHORT_8_8_REV_MESA, data);
       break;
     case GST_VIDEO_FORMAT_UYVY:
-      buffer->format = GST_GL_BUFFER_FORMAT_YUYV;
-      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_YCBCR_MESA, width, height,
-          0, GL_YCBCR_MESA, GL_UNSIGNED_SHORT_8_8_REV_MESA, NULL);
       glTexSubImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, 0, 0, width, height,
           GL_YCBCR_MESA, GL_UNSIGNED_SHORT_8_8_MESA, data);
       break;
-    case GST_VIDEO_FORMAT_AYUV:
-      buffer->format = GST_GL_BUFFER_FORMAT_RGB;
-      buffer->is_yuv = TRUE;
-      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_RGBA,
-          buffer->width, buffer->height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
-      glTexSubImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, 0, 0, width, height,
-          GL_BGRA, GL_UNSIGNED_INT_8_8_8_8, data);
-      break;
     case GST_VIDEO_FORMAT_I420:
     case GST_VIDEO_FORMAT_YV12:
-      buffer->format = GST_GL_BUFFER_FORMAT_PLANAR420;
-      buffer->is_yuv = TRUE;
-      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_LUMINANCE,
-          buffer->width, buffer->height,
-          0, GL_LUMINANCE, GL_UNSIGNED_BYTE, NULL);
       glTexSubImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, 0, 0, width, height,
           GL_LUMINANCE, GL_UNSIGNED_BYTE, data);
 
-      glGenTextures (1, &buffer->texture_u);
       glBindTexture (GL_TEXTURE_RECTANGLE_ARB, buffer->texture_u);
-      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_LUMINANCE,
-          GST_ROUND_UP_2 (buffer->width) / 2,
-          GST_ROUND_UP_2 (buffer->height) / 2,
-          0, GL_LUMINANCE, GL_UNSIGNED_BYTE, NULL);
-      comp = (format == GST_VIDEO_FORMAT_I420) ? 1 : 2;
       glTexSubImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, 0, 0,
           GST_ROUND_UP_2 (buffer->width) / 2,
           GST_ROUND_UP_2 (buffer->height) / 2,
           GL_LUMINANCE, GL_UNSIGNED_BYTE,
           (guint8 *) data +
-          gst_video_format_get_component_offset (format, comp, width, height));
+          gst_video_format_get_component_offset (video_format, 1, width,
+              height));
 
-      glGenTextures (1, &buffer->texture_v);
       glBindTexture (GL_TEXTURE_RECTANGLE_ARB, buffer->texture_v);
-      glTexImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, GL_LUMINANCE,
-          GST_ROUND_UP_2 (buffer->width) / 2,
-          GST_ROUND_UP_2 (buffer->height) / 2,
-          0, GL_LUMINANCE, GL_UNSIGNED_BYTE, NULL);
-      comp = (format == GST_VIDEO_FORMAT_I420) ? 2 : 1;
       glTexSubImage2D (GL_TEXTURE_RECTANGLE_ARB, 0, 0, 0,
           GST_ROUND_UP_2 (buffer->width) / 2,
           GST_ROUND_UP_2 (buffer->height) / 2,
           GL_LUMINANCE, GL_UNSIGNED_BYTE,
           (guint8 *) data +
-          gst_video_format_get_component_offset (format, comp, width, height));
+          gst_video_format_get_component_offset (video_format, 2, width,
+              height));
       break;
     default:
       g_assert_not_reached ();
   }
 
   gst_gl_display_unlock (buffer->display);
-
-  return buffer;
 }
 
 
 void
-gst_gl_buffer_download (GstGLBuffer * buffer, GstVideoFormat format, void *data)
+gst_gl_buffer_download (GstGLBuffer * buffer, GstVideoFormat video_format,
+    void *data)
 {
   GLuint fbo;
 
+  g_return_if_fail (buffer->format ==
+      gst_gl_buffer_format_from_video_format (video_format));
+
   GST_DEBUG ("downloading");
 
   gst_gl_display_lock (buffer->display);
 
+  /* we need a reset function */
+  glMatrixMode (GL_COLOR);
+  glLoadIdentity ();
+  glPixelTransferf (GL_POST_COLOR_MATRIX_RED_BIAS, 0);
+  glPixelTransferf (GL_POST_COLOR_MATRIX_GREEN_BIAS, 0);
+  glPixelTransferf (GL_POST_COLOR_MATRIX_BLUE_BIAS, 0);
+
   glGenFramebuffersEXT (1, &fbo);
   glBindFramebufferEXT (GL_FRAMEBUFFER_EXT, fbo);
 
@@ -260,14 +328,7 @@ gst_gl_buffer_download (GstGLBuffer * buffer, GstVideoFormat format, void *data)
   g_assert (glCheckFramebufferStatusEXT (GL_FRAMEBUFFER_EXT) ==
       GL_FRAMEBUFFER_COMPLETE_EXT);
 
-  /* we need a reset function */
-  glMatrixMode (GL_COLOR);
-  glLoadIdentity ();
-  glPixelTransferf (GL_POST_COLOR_MATRIX_RED_BIAS, 0);
-  glPixelTransferf (GL_POST_COLOR_MATRIX_GREEN_BIAS, 0);
-  glPixelTransferf (GL_POST_COLOR_MATRIX_BLUE_BIAS, 0);
-
-  switch (format) {
+  switch (video_format) {
     case GST_VIDEO_FORMAT_RGBx:
       glReadPixels (0, 0, buffer->width, buffer->height, GL_RGBA,
           GL_UNSIGNED_BYTE, data);
@@ -280,10 +341,42 @@ gst_gl_buffer_download (GstGLBuffer * buffer, GstVideoFormat format, void *data)
       glReadPixels (0, 0, buffer->width, buffer->height, GL_RGBA,
           GL_UNSIGNED_INT_8_8_8_8, data);
       break;
+    case GST_VIDEO_FORMAT_AYUV:
     case GST_VIDEO_FORMAT_xRGB:
       glReadPixels (0, 0, buffer->width, buffer->height, GL_BGRA,
           GL_UNSIGNED_INT_8_8_8_8, data);
       break;
+    case GST_VIDEO_FORMAT_YUY2:
+    case GST_VIDEO_FORMAT_UYVY:
+      g_warning ("video format not supported for download from GL texture");
+      break;
+    case GST_VIDEO_FORMAT_I420:
+    case GST_VIDEO_FORMAT_YV12:
+      glReadPixels (0, 0, buffer->width, buffer->height,
+          GL_LUMINANCE, GL_UNSIGNED_BYTE, data);
+
+      glFramebufferTexture2DEXT (GL_FRAMEBUFFER_EXT,
+          GL_COLOR_ATTACHMENT1_EXT, GL_TEXTURE_RECTANGLE_ARB,
+          buffer->texture_u, 0);
+      glReadPixels (0, 0,
+          GST_ROUND_UP_2 (buffer->width) / 2,
+          GST_ROUND_UP_2 (buffer->height) / 2,
+          GL_LUMINANCE, GL_UNSIGNED_BYTE,
+          (guint8 *) data +
+          gst_video_format_get_component_offset (video_format, 1, buffer->width,
+              buffer->height));
+
+      glFramebufferTexture2DEXT (GL_FRAMEBUFFER_EXT,
+          GL_COLOR_ATTACHMENT1_EXT, GL_TEXTURE_RECTANGLE_ARB,
+          buffer->texture_v, 0);
+      glReadPixels (0, 0,
+          GST_ROUND_UP_2 (buffer->width) / 2,
+          GST_ROUND_UP_2 (buffer->height) / 2,
+          GL_LUMINANCE, GL_UNSIGNED_BYTE,
+          (guint8 *) data +
+          gst_video_format_get_component_offset (video_format, 2, buffer->width,
+              buffer->height));
+      break;
     default:
       g_assert_not_reached ();
   }
@@ -292,3 +385,67 @@ gst_gl_buffer_download (GstGLBuffer * buffer, GstVideoFormat format, void *data)
 
   gst_gl_display_unlock (buffer->display);
 }
+
+
+
+/* buffer format */
+
+GstGLBufferFormat
+gst_gl_buffer_format_from_video_format (GstVideoFormat format)
+{
+  switch (format) {
+    case GST_VIDEO_FORMAT_RGBx:
+    case GST_VIDEO_FORMAT_BGRx:
+    case GST_VIDEO_FORMAT_xRGB:
+    case GST_VIDEO_FORMAT_xBGR:
+    case GST_VIDEO_FORMAT_RGBA:
+    case GST_VIDEO_FORMAT_BGRA:
+    case GST_VIDEO_FORMAT_ARGB:
+    case GST_VIDEO_FORMAT_ABGR:
+    case GST_VIDEO_FORMAT_AYUV:
+      return GST_GL_BUFFER_FORMAT_RGBA;
+    case GST_VIDEO_FORMAT_RGB:
+    case GST_VIDEO_FORMAT_BGR:
+      return GST_GL_BUFFER_FORMAT_RGB;
+    case GST_VIDEO_FORMAT_YUY2:
+    case GST_VIDEO_FORMAT_UYVY:
+      return GST_GL_BUFFER_FORMAT_YUYV;
+    case GST_VIDEO_FORMAT_I420:
+    case GST_VIDEO_FORMAT_YV12:
+      return GST_GL_BUFFER_FORMAT_PLANAR420;
+    case GST_VIDEO_FORMAT_UNKNOWN:
+      return GST_GL_BUFFER_FORMAT_UNKNOWN;
+  }
+
+  g_return_val_if_reached (GST_GL_BUFFER_FORMAT_UNKNOWN);
+}
+
+int
+gst_gl_buffer_format_get_size (GstGLBufferFormat format, int width, int height)
+{
+  /* this is not strictly true, but it's used for compatibility with
+   * queue and BaseTransform */
+  return width * height * 4;
+}
+
+gboolean
+gst_gl_buffer_format_parse_caps (GstCaps * caps, GstGLBufferFormat * format,
+    int *width, int *height)
+{
+  GstStructure *structure;
+  int format_as_int;
+  gboolean ret;
+
+  structure = gst_caps_get_structure (caps, 0);
+
+  if (!gst_structure_has_name (structure, "video/x-raw-gl")) {
+    return FALSE;
+  }
+
+  ret = gst_structure_get_int (structure, "format", &format_as_int);
+  *format = format_as_int;
+  ret &= gst_structure_get_int (structure, "width", width);
+  ret &= gst_structure_get_int (structure, "height", height);
+
+  return ret;
+}
diff --git a/sys/glsink/gstglbuffer.h b/sys/glsink/gstglbuffer.h
index e5a39441..cf2e0141 100644
--- a/sys/glsink/gstglbuffer.h
+++ b/sys/glsink/gstglbuffer.h
@@ -14,6 +14,7 @@ typedef struct _GstGLBuffer GstGLBuffer;
 #define GST_GL_BUFFER(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_GL_BUFFER, GstGLBuffer))
 
 typedef enum {
+  GST_GL_BUFFER_FORMAT_UNKNOWN,
   GST_GL_BUFFER_FORMAT_RGBA,
   GST_GL_BUFFER_FORMAT_RGB,
   GST_GL_BUFFER_FORMAT_YUYV,
@@ -41,21 +42,32 @@ struct _GstGLBuffer {
 GType gst_gl_buffer_get_type (void);
 
 GstGLBuffer * gst_gl_buffer_new (GstGLDisplay *display,
+    int width, int height);
+GstGLBuffer * gst_gl_buffer_new_with_format (GstGLDisplay *display,
     GstGLBufferFormat format, int width, int height);
-GstGLBuffer * gst_gl_buffer_new_from_data (GstGLDisplay *display,
-    GstVideoFormat format, int width, int height, void *data);
+GstGLBuffer * gst_gl_buffer_new_from_video_format (GstGLDisplay *display,
+    GstVideoFormat format, int width, int height);
+void gst_gl_buffer_upload (GstGLBuffer *buffer,
+    GstVideoFormat format, void *data);
 void gst_gl_buffer_download (GstGLBuffer *buffer, GstVideoFormat format,
     void *data);
 
 
 #define GST_GL_VIDEO_CAPS \
   "video/x-raw-gl," \
-  "format=(int)[0,10]," \
+  "format=(int)1," \
+  "is_yuv=(boolean)FALSE," \
   "width=(int)[1,2048]," \
   "height=(int)[1,2048]," \
   "pixel-aspect-ratio=(fraction)1/1," \
   "framerate=(fraction)[0/1,100/1]"
 
+GstGLBufferFormat gst_gl_buffer_format_from_video_format (GstVideoFormat format);
+int gst_gl_buffer_format_get_size (GstGLBufferFormat format, int width,
+    int height);
+gboolean gst_gl_buffer_format_parse_caps (GstCaps *caps, GstGLBufferFormat *format,
+    int *width, int *height);
+
 
 #endif
 
diff --git a/sys/glsink/gstglconvert.c b/sys/glsink/gstglconvert.c
index 57daec5a..f4f525e9 100644
--- a/sys/glsink/gstglconvert.c
+++ b/sys/glsink/gstglconvert.c
@@ -58,24 +58,6 @@ static const GstElementDetails element_details = GST_ELEMENT_DETAILS ("FIXME",
     "FIXME GL conversion filter",
     "FIXME <fixme@fixme.com>");
 
-#if 0
-#define GST_GL_VIDEO_CAPS "video/x-raw-gl"
-
-static GstStaticPadTemplate gst_gl_convert_src_pad_template =
-GST_STATIC_PAD_TEMPLATE ("src",
-    GST_PAD_SRC,
-    GST_PAD_ALWAYS,
-    GST_STATIC_CAPS (GST_GL_VIDEO_CAPS)
-    );
-
-static GstStaticPadTemplate gst_gl_convert_sink_pad_template =
-GST_STATIC_PAD_TEMPLATE ("sink",
-    GST_PAD_SINK,
-    GST_PAD_ALWAYS,
-    GST_STATIC_CAPS (GST_GL_VIDEO_CAPS)
-    );
-#endif
-
 enum
 {
   PROP_0
@@ -92,11 +74,8 @@ static void gst_gl_convert_set_property (GObject * object, guint prop_id,
 static void gst_gl_convert_get_property (GObject * object, guint prop_id,
     GValue * value, GParamSpec * pspec);
 
-static void gst_gl_convert_reset (GstGLConvert * filter);
-static gboolean gst_gl_convert_transform (GstGLFilter * filter,
-    GstGLBuffer * outbuf, GstGLBuffer * inbuf);
-static gboolean gst_gl_convert_start (GstGLFilter * _filter);
-static gboolean gst_gl_convert_stop (GstGLFilter * _filter);
+static gboolean gst_gl_convert_filter (GstGLFilter * filter,
+    GstGLBuffer * inbuf, GstGLBuffer * outbuf);
 
 
 static void
@@ -105,13 +84,6 @@ gst_gl_convert_base_init (gpointer klass)
   GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
 
   gst_element_class_set_details (element_class, &element_details);
-
-#if 0
-  gst_element_class_add_pad_template (element_class,
-      gst_static_pad_template_get (&gst_gl_convert_src_pad_template));
-  gst_element_class_add_pad_template (element_class,
-      gst_static_pad_template_get (&gst_gl_convert_sink_pad_template));
-#endif
 }
 
 static void
@@ -123,15 +95,12 @@ gst_gl_convert_class_init (GstGLConvertClass * klass)
   gobject_class->set_property = gst_gl_convert_set_property;
   gobject_class->get_property = gst_gl_convert_get_property;
 
-  GST_GL_FILTER_CLASS (klass)->transform = gst_gl_convert_transform;
-  GST_GL_FILTER_CLASS (klass)->start = gst_gl_convert_start;
-  GST_GL_FILTER_CLASS (klass)->stop = gst_gl_convert_stop;
+  GST_GL_FILTER_CLASS (klass)->filter = gst_gl_convert_filter;
 }
 
 static void
 gst_gl_convert_init (GstGLConvert * filter, GstGLConvertClass * klass)
 {
-  gst_gl_convert_reset (filter);
 }
 
 static void
@@ -160,33 +129,9 @@ gst_gl_convert_get_property (GObject * object, guint prop_id,
   }
 }
 
-static void
-gst_gl_convert_reset (GstGLConvert * filter)
-{
-
-}
-
-static gboolean
-gst_gl_convert_start (GstGLFilter * _filter)
-{
-  //GstGLConvert *convert = GST_GL_CONVERT(_filter);
-
-  return TRUE;
-}
-
-static gboolean
-gst_gl_convert_stop (GstGLFilter * _filter)
-{
-  GstGLConvert *convert = GST_GL_CONVERT (_filter);
-
-  gst_gl_convert_reset (convert);
-
-  return TRUE;
-}
-
 static gboolean
-gst_gl_convert_transform (GstGLFilter * filter, GstGLBuffer * outbuf,
-    GstGLBuffer * inbuf)
+gst_gl_convert_filter (GstGLFilter * filter, GstGLBuffer * inbuf,
+    GstGLBuffer * outbuf)
 {
   //GstGLConvert *convert = GST_GL_CONVERT(filter);
 
diff --git a/sys/glsink/gstgldisplay.c b/sys/glsink/gstgldisplay.c
index 6d93c889..f0995c1b 100644
--- a/sys/glsink/gstgldisplay.c
+++ b/sys/glsink/gstgldisplay.c
@@ -57,15 +57,17 @@ gst_gl_display_finalize (GObject * object)
 {
   GstGLDisplay *display = GST_GL_DISPLAY (object);
 
-  if (display->assigned_window == None) {
+  GST_DEBUG ("finalize %p", object);
+
+  if (display->window != None) {
     XDestroyWindow (display->display, display->window);
   }
   if (display->context) {
     glXDestroyContext (display->display, display->context);
   }
-  if (display->visinfo) {
-    XFree (display->visinfo);
-  }
+  //if (display->visinfo) {
+  //  XFree (display->visinfo);
+  //}
   if (display->display) {
     XCloseDisplay (display->display);
   }
@@ -165,11 +167,28 @@ gst_gl_display_check_features (GstGLDisplay * display)
     GST_DEBUG ("No GLX extension");
     return FALSE;
   }
+#if 0
+  {
+    int i;
+    int n;
+
+    visinfo = XGetVisualInfo (display->display, 0, NULL, &n);
+    for (i = 0; i < n; i++) {
+      GST_ERROR ("%d: %d %ld", i, visinfo[i].depth, visinfo[i].visualid);
+      if (visinfo[i].depth == 32)
+        break;
+    }
 
-  visinfo = glXChooseVisual (display->display, scrnum, attrib);
-  if (visinfo == NULL) {
-    GST_DEBUG ("No usable visual");
-    return FALSE;
+    visinfo += i;
+  }
+#endif
+
+  if (1) {
+    visinfo = glXChooseVisual (display->display, scrnum, attrib);
+    if (visinfo == NULL) {
+      GST_DEBUG ("No usable visual");
+      return FALSE;
+    }
   }
 
   display->visinfo = visinfo;
@@ -185,6 +204,8 @@ gst_gl_display_check_features (GstGLDisplay * display)
 
   mask = CWBackPixel | CWBorderPixel | CWColormap | CWOverrideRedirect;
 
+  GST_ERROR ("creating window with visual %ld", visinfo->visualid);
+
   window = XCreateWindow (display->display, root, 0, 0,
       100, 100, 0, visinfo->depth, InputOutput, visinfo->visual, mask, &attr);
 
@@ -245,8 +266,16 @@ gst_gl_display_can_handle_type (GstGLDisplay * display, GstVideoFormat type)
 void
 gst_gl_display_lock (GstGLDisplay * display)
 {
+  gboolean ret;
+
+  g_assert (display->window != None);
+  g_assert (display->context != NULL);
+
   g_mutex_lock (display->lock);
-  glXMakeCurrent (display->display, display->window, display->context);
+  ret = glXMakeCurrent (display->display, display->window, display->context);
+  if (!ret) {
+    g_warning ("glxMakeCurrent failed");
+  }
   gst_gl_display_check_error (display, __LINE__);
 }
 
@@ -265,7 +294,10 @@ gst_gl_display_init_tmp_window (GstGLDisplay * display)
   int scrnum;
   int mask;
   Window root;
+  Window parent_window;
   Screen *screen;
+  int width;
+  int height;
 
   GST_DEBUG ("creating temp window");
 
@@ -277,20 +309,29 @@ gst_gl_display_init_tmp_window (GstGLDisplay * display)
   attr.border_pixel = 0;
   attr.colormap = XCreateColormap (display->display, root,
       display->visinfo->visual, AllocNone);
-  attr.override_redirect = False;
-#if 0
-  if (display->parent_window) {
+  if (display->parent_window != None) {
+    XWindowAttributes parent_attr;
+
     attr.override_redirect = True;
+    parent_window = display->parent_window;
+
+    XGetWindowAttributes (display->display, parent_window, &parent_attr);
+    width = parent_attr.width;
+    height = parent_attr.height;
+  } else {
+    attr.override_redirect = False;
+    parent_window = root;
+    width = 100;
+    height = 100;
   }
-#endif
 
   mask = CWBackPixel | CWBorderPixel | CWColormap | CWOverrideRedirect;
 
   display->window = XCreateWindow (display->display,
-      root, 0, 0, 100, 100,
+      parent_window, 0, 0, width, height,
       0, display->visinfo->depth, InputOutput,
       display->visinfo->visual, mask, &attr);
-  //XMapWindow (display->display, display->window);
+  XMapWindow (display->display, display->window);
   XSync (display->display, FALSE);
 }
 
@@ -305,6 +346,7 @@ gst_gl_display_set_window (GstGLDisplay * display, Window window)
 {
   g_mutex_lock (display->lock);
 
+#if 0
   if (window != display->assigned_window) {
     if (display->assigned_window == None) {
       gst_gl_display_destroy_tmp_window (display);
@@ -316,6 +358,18 @@ gst_gl_display_set_window (GstGLDisplay * display, Window window)
       display->window = window;
     }
   }
+#else
+  if (window != display->parent_window) {
+    gst_gl_display_destroy_tmp_window (display);
+
+    display->parent_window = window;
+
+    gst_gl_display_init_tmp_window (display);
+
+    //XReparentWindow (display->display, display->window,
+    //  display->assigned_window, 0, 0);
+  }
+#endif
 
   g_mutex_unlock (display->lock);
 }
@@ -327,6 +381,10 @@ gst_gl_display_update_attributes (GstGLDisplay * display)
 
   if (display->window != None) {
     XGetWindowAttributes (display->display, display->window, &attr);
+
+    GST_DEBUG ("window visual %ld display visual %ld",
+        attr.visual->visualid, display->visinfo->visual->visualid);
+
     display->win_width = attr.width;
     display->win_height = attr.height;
   } else {
@@ -670,7 +728,7 @@ gst_gl_display_draw_image (GstGLDisplay * display, GstVideoFormat type,
 
   gst_gl_display_update_attributes (display);
 
-  //glXSwapIntervalSGI (1);
+  glXSwapIntervalSGI (1);
   glViewport (0, 0, display->win_width, display->win_height);
 
   glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
diff --git a/sys/glsink/gstgldisplay.h b/sys/glsink/gstgldisplay.h
index 677c569f..907f2c8f 100644
--- a/sys/glsink/gstgldisplay.h
+++ b/sys/glsink/gstgldisplay.h
@@ -46,7 +46,8 @@ struct _GstGLDisplay {
   gboolean have_color_matrix;
 
   Window window;
-  Window assigned_window;
+  //Window assigned_window;
+  Window parent_window;
 
   int win_width;
   int win_height;
diff --git a/sys/glsink/gstgldownload.c b/sys/glsink/gstgldownload.c
index b5a3f1b2..4c460b9b 100644
--- a/sys/glsink/gstgldownload.c
+++ b/sys/glsink/gstgldownload.c
@@ -217,6 +217,8 @@ gst_gl_download_transform_caps (GstBaseTransform * bt,
 
   download = GST_GL_DOWNLOAD (bt);
 
+  GST_ERROR ("transform caps %" GST_PTR_FORMAT, caps);
+
   structure = gst_caps_get_structure (caps, 0);
 
   width_value = gst_structure_get_value (structure, "width");
@@ -227,7 +229,9 @@ gst_gl_download_transform_caps (GstBaseTransform * bt,
   if (direction == GST_PAD_SINK) {
     newcaps = gst_caps_new_simple ("video/x-raw-rgb", NULL);
   } else {
-    newcaps = gst_caps_new_simple ("video/x-raw-gl", NULL);
+    newcaps = gst_caps_new_simple ("video/x-raw-gl",
+        "format", G_TYPE_INT, GST_GL_BUFFER_FORMAT_RGBA,
+        "is_yuv", G_TYPE_BOOLEAN, FALSE, NULL);
   }
   newstruct = gst_caps_get_structure (newcaps, 0);
   gst_structure_set_value (newstruct, "width", width_value);
@@ -240,6 +244,8 @@ gst_gl_download_transform_caps (GstBaseTransform * bt,
         1, 1, NULL);
   }
 
+  GST_ERROR ("new caps %" GST_PTR_FORMAT, newcaps);
+
   return newcaps;
 }
 
@@ -258,7 +264,7 @@ gst_gl_download_set_caps (GstBaseTransform * bt, GstCaps * incaps,
       &download->width, &download->height);
 
   if (!ret) {
-    GST_DEBUG ("bad caps");
+    GST_ERROR ("bad caps");
     return FALSE;
   }
 
@@ -271,30 +277,27 @@ gst_gl_download_get_unit_size (GstBaseTransform * trans, GstCaps * caps,
 {
   gboolean ret;
   GstStructure *structure;
+  int width;
+  int height;
 
   structure = gst_caps_get_structure (caps, 0);
   if (gst_structure_has_name (structure, "video/x-raw-gl")) {
-    int width;
-    int height;
-
-    ret = gst_structure_get_int (structure, "width", &width);
-    ret &= gst_structure_get_int (structure, "height", &height);
+    GstGLBufferFormat format;
 
-    /* FIXME */
-    *size = width * height * 4;
+    ret = gst_gl_buffer_format_parse_caps (caps, &format, &width, &height);
+    if (ret) {
+      *size = gst_gl_buffer_format_get_size (format, width, height);
+    }
   } else {
-    int width;
-    int height;
+    GstVideoFormat format;
 
-    ret = gst_structure_get_int (structure, "width", &width);
-    ret &= gst_structure_get_int (structure, "height", &height);
-
-    /* FIXME */
-    *size = width * height * 4;
+    ret = gst_video_format_parse_caps (caps, &format, &width, &height);
+    if (ret) {
+      *size = gst_video_format_get_size (format, width, height);
+    }
   }
 
-
-  return TRUE;
+  return ret;
 }
 
 static GstFlowReturn
diff --git a/sys/glsink/gstglfilter.c b/sys/glsink/gstglfilter.c
index 1ff05adf..a2175aff 100644
--- a/sys/glsink/gstglfilter.c
+++ b/sys/glsink/gstglfilter.c
@@ -49,21 +49,27 @@ GST_STATIC_PAD_TEMPLATE ("sink",
 #define DEBUG_INIT(bla) \
   GST_DEBUG_CATEGORY_INIT (gst_gl_filter_debug, "glfilter", 0, "glfilter element");
 
-GST_BOILERPLATE_FULL (GstGLFilter, gst_gl_filter, GstElement,
-    GST_TYPE_ELEMENT, DEBUG_INIT);
+GST_BOILERPLATE_FULL (GstGLFilter, gst_gl_filter, GstBaseTransform,
+    GST_TYPE_BASE_TRANSFORM, DEBUG_INIT);
 
 static void gst_gl_filter_set_property (GObject * object, guint prop_id,
     const GValue * value, GParamSpec * pspec);
 static void gst_gl_filter_get_property (GObject * object, guint prop_id,
     GValue * value, GParamSpec * pspec);
 
-static GstFlowReturn gst_gl_filter_chain (GstPad * pad, GstBuffer * buf);
 static void gst_gl_filter_reset (GstGLFilter * filter);
-static GstStateChangeReturn
-gst_gl_filter_change_state (GstElement * element, GstStateChange transition);
-static gboolean gst_gl_filter_sink_setcaps (GstPad * pad, GstCaps * caps);
+static gboolean gst_gl_filter_start (GstBaseTransform * bt);
+static gboolean gst_gl_filter_stop (GstBaseTransform * bt);
+static gboolean gst_gl_filter_get_unit_size (GstBaseTransform * trans,
+    GstCaps * caps, guint * size);
+static GstFlowReturn gst_gl_filter_transform (GstBaseTransform * bt,
+    GstBuffer * inbuf, GstBuffer * outbuf);
+static GstFlowReturn gst_gl_filter_prepare_output_buffer (GstBaseTransform *
+    trans, GstBuffer * input, gint size, GstCaps * caps, GstBuffer ** buf);
+static gboolean gst_gl_filter_set_caps (GstBaseTransform * bt, GstCaps * incaps,
+    GstCaps * outcaps);
 static gboolean gst_gl_filter_do_transform (GstGLFilter * filter,
-    GstGLBuffer * outbuf, GstGLBuffer * inbuf);
+    GstGLBuffer * inbuf, GstGLBuffer * outbuf);
 
 
 static void
@@ -86,20 +92,23 @@ gst_gl_filter_class_init (GstGLFilterClass * klass)
   gobject_class->set_property = gst_gl_filter_set_property;
   gobject_class->get_property = gst_gl_filter_get_property;
 
-  GST_ELEMENT_CLASS (klass)->change_state = gst_gl_filter_change_state;
+  GST_BASE_TRANSFORM_CLASS (klass)->transform = gst_gl_filter_transform;
+  GST_BASE_TRANSFORM_CLASS (klass)->start = gst_gl_filter_start;
+  GST_BASE_TRANSFORM_CLASS (klass)->stop = gst_gl_filter_stop;
+  GST_BASE_TRANSFORM_CLASS (klass)->set_caps = gst_gl_filter_set_caps;
+  GST_BASE_TRANSFORM_CLASS (klass)->get_unit_size = gst_gl_filter_get_unit_size;
+  GST_BASE_TRANSFORM_CLASS (klass)->prepare_output_buffer =
+      gst_gl_filter_prepare_output_buffer;
 }
 
 static void
 gst_gl_filter_init (GstGLFilter * filter, GstGLFilterClass * klass)
 {
-  gst_element_create_all_pads (GST_ELEMENT (filter));
+  //gst_element_create_all_pads (GST_ELEMENT (filter));
 
   filter->sinkpad = gst_element_get_static_pad (GST_ELEMENT (filter), "sink");
   filter->srcpad = gst_element_get_static_pad (GST_ELEMENT (filter), "src");
 
-  gst_pad_set_setcaps_function (filter->sinkpad, gst_gl_filter_sink_setcaps);
-  gst_pad_set_chain_function (filter->sinkpad, gst_gl_filter_chain);
-
   gst_gl_filter_reset (filter);
 }
 
@@ -136,143 +145,108 @@ gst_gl_filter_reset (GstGLFilter * filter)
     g_object_unref (filter->display);
     filter->display = NULL;
   }
-  filter->format = GST_GL_BUFFER_FORMAT_RGB;
+  filter->format = GST_GL_BUFFER_FORMAT_UNKNOWN;
+  filter->width = 0;
+  filter->height = 0;
 }
 
 static gboolean
-gst_gl_filter_start (GstGLFilter * filter)
+gst_gl_filter_start (GstBaseTransform * bt)
 {
-  GstGLFilterClass *filter_class;
-  gboolean ret;
-
-  filter_class = GST_GL_FILTER_GET_CLASS (filter);
-
-  filter->format = GST_GL_BUFFER_FORMAT_RGB;
-  filter->display = gst_gl_display_new ();
-  ret = gst_gl_display_connect (filter->display, NULL);
-  if (!ret)
-    return FALSE;
 
-  if (filter_class->start) {
-    ret = filter_class->start (filter);
-  }
-
-  return ret;
+  return TRUE;
 }
 
 static gboolean
-gst_gl_filter_stop (GstGLFilter * filter)
+gst_gl_filter_stop (GstBaseTransform * bt)
 {
-  GstGLFilterClass *filter_class;
-  gboolean ret;
-
-  filter_class = GST_GL_FILTER_GET_CLASS (filter);
+  GstGLFilter *filter = GST_GL_FILTER (bt);
 
   gst_gl_filter_reset (filter);
 
-  if (filter_class->stop) {
-    ret = filter_class->stop (filter);
-  }
-
-  g_object_unref (filter->display);
-  filter->display = NULL;
-
   return TRUE;
 }
 
 static gboolean
-gst_gl_filter_sink_setcaps (GstPad * pad, GstCaps * caps)
+gst_gl_filter_get_unit_size (GstBaseTransform * trans, GstCaps * caps,
+    guint * size)
 {
-  GstGLFilter *filter;
   gboolean ret;
-  GstStructure *structure;
-
-  filter = GST_GL_FILTER (gst_pad_get_parent (pad));
-
-  structure = gst_caps_get_structure (caps, 0);
+  GstGLBufferFormat format;
+  int width;
+  int height;
 
-  ret = gst_structure_get_int (structure, "width", &filter->width);
-  ret &= gst_structure_get_int (structure, "height", &filter->height);
-  if (!ret)
-    return FALSE;
-
-  GST_DEBUG ("setcaps %d %d", filter->width, filter->height);
-
-  ret = gst_pad_set_caps (filter->srcpad, caps);
+  ret = gst_gl_buffer_format_parse_caps (caps, &format, &width, &height);
+  if (ret) {
+    *size = gst_gl_buffer_format_get_size (format, width, height);
+  }
 
-  return ret;
+  return TRUE;
 }
 
 static GstFlowReturn
-gst_gl_filter_chain (GstPad * pad, GstBuffer * buf)
+gst_gl_filter_prepare_output_buffer (GstBaseTransform * trans,
+    GstBuffer * inbuf, gint size, GstCaps * caps, GstBuffer ** buf)
 {
   GstGLFilter *filter;
-  GstGLBuffer *inbuf;
-  GstGLBuffer *outbuf;
+  GstGLBuffer *gl_inbuf = GST_GL_BUFFER (inbuf);
+  GstGLBuffer *gl_outbuf;
 
-  filter = GST_GL_FILTER (gst_pad_get_parent (pad));
-  inbuf = GST_GL_BUFFER (buf);
+  filter = GST_GL_FILTER (trans);
 
-  outbuf = gst_gl_buffer_new (inbuf->display, filter->format,
-      filter->width, filter->height);
-
-  gst_buffer_copy_metadata (GST_BUFFER (outbuf), buf,
-      GST_BUFFER_COPY_TIMESTAMPS | GST_BUFFER_COPY_FLAGS);
-  gst_buffer_set_caps (GST_BUFFER (outbuf), GST_PAD_CAPS (filter->srcpad));
+  if (filter->display == NULL) {
+    filter->display = gl_inbuf->display;
+  }
 
-  gst_gl_filter_do_transform (filter, outbuf, inbuf);
+  gl_outbuf = gst_gl_buffer_new_with_format (filter->display,
+      filter->format, filter->width, filter->height);
 
-  gst_pad_push (filter->srcpad, GST_BUFFER (outbuf));
+  *buf = GST_BUFFER (gl_outbuf);
+  gst_buffer_set_caps (*buf, caps);
 
-  gst_buffer_unref (buf);
-  gst_object_unref (filter);
   return GST_FLOW_OK;
 }
 
-static GstStateChangeReturn
-gst_gl_filter_change_state (GstElement * element, GstStateChange transition)
+static gboolean
+gst_gl_filter_set_caps (GstBaseTransform * bt, GstCaps * incaps,
+    GstCaps * outcaps)
 {
   GstGLFilter *filter;
-  GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
+  gboolean ret;
 
-  GST_DEBUG ("change state");
+  filter = GST_GL_FILTER (bt);
 
-  filter = GST_GL_FILTER (element);
+  ret = gst_gl_buffer_format_parse_caps (incaps, &filter->format,
+      &filter->width, &filter->height);
 
-  switch (transition) {
-    case GST_STATE_CHANGE_NULL_TO_READY:
-      break;
-    case GST_STATE_CHANGE_READY_TO_PAUSED:
-      gst_gl_filter_start (filter);
-      break;
-    case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
-      break;
-    default:
-      break;
+  if (!ret) {
+    GST_DEBUG ("bad caps");
+    return FALSE;
   }
 
-  ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
-  if (ret == GST_STATE_CHANGE_FAILURE)
-    return ret;
-
-  switch (transition) {
-    case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
-      break;
-    case GST_STATE_CHANGE_PAUSED_TO_READY:
-      gst_gl_filter_stop (filter);
-      break;
-    case GST_STATE_CHANGE_READY_TO_NULL:
-      break;
-    default:
-      break;
-  }
+  GST_ERROR ("set_caps %d %d", filter->width, filter->height);
 
   return ret;
 }
 
+static GstFlowReturn
+gst_gl_filter_transform (GstBaseTransform * bt, GstBuffer * inbuf,
+    GstBuffer * outbuf)
+{
+  GstGLFilter *filter;
+  GstGLBuffer *gl_inbuf = GST_GL_BUFFER (inbuf);
+  GstGLBuffer *gl_outbuf = GST_GL_BUFFER (outbuf);
+
+  filter = GST_GL_FILTER (bt);
+
+  gst_gl_filter_do_transform (filter, gl_inbuf, gl_outbuf);
+
+  return GST_FLOW_OK;
+}
+
 static gboolean
 gst_gl_filter_do_transform (GstGLFilter * filter,
-    GstGLBuffer * outbuf, GstGLBuffer * inbuf)
+    GstGLBuffer * inbuf, GstGLBuffer * outbuf)
 {
   GstGLDisplay *display = inbuf->display;
   GstGLFilterClass *filter_class;
@@ -311,9 +285,10 @@ gst_gl_filter_do_transform (GstGLFilter * filter,
   glColor4f (1, 1, 1, 1);
 
   glEnable (GL_TEXTURE_RECTANGLE_ARB);
+  glActiveTexture (GL_TEXTURE0);
   glBindTexture (GL_TEXTURE_RECTANGLE_ARB, inbuf->texture);
 
-  filter_class->transform (filter, outbuf, inbuf);
+  filter_class->filter (filter, inbuf, outbuf);
 
 #if 0
   glTexParameteri (GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
diff --git a/sys/glsink/gstglfilter.h b/sys/glsink/gstglfilter.h
index 01b915f5..513d6e9b 100644
--- a/sys/glsink/gstglfilter.h
+++ b/sys/glsink/gstglfilter.h
@@ -23,6 +23,7 @@
 
 #include <gst/gst.h>
 #include <gst/video/video.h>
+#include <gst/base/gstbasetransform.h>
 #include <gstglbuffer.h>
 
 #define GST_TYPE_GL_FILTER            (gst_gl_filter_get_type())
@@ -35,13 +36,11 @@ typedef struct _GstGLFilter GstGLFilter;
 typedef struct _GstGLFilterClass GstGLFilterClass;
 
 typedef gboolean (*GstGLFilterProcessFunc) (GstGLFilter *filter,
-    GstGLBuffer *outbuf, GstGLBuffer *inbuf);
-typedef gboolean (*GstGLFilterStartFunc) (GstGLFilter *filter);
-typedef gboolean (*GstGLFilterStopFunc) (GstGLFilter *filter);
+    GstGLBuffer *inbuf, GstGLBuffer *outbuf);
 
 struct _GstGLFilter
 {
-  GstElement element;
+  GstBaseTransform base_transform;
 
   GstPad *srcpad;
   GstPad *sinkpad;
@@ -56,10 +55,8 @@ struct _GstGLFilter
 
 struct _GstGLFilterClass
 {
-  GstElementClass element_class;
-  GstGLFilterProcessFunc transform;
-  GstGLFilterStartFunc start;
-  GstGLFilterStopFunc stop;
+  GstBaseTransformClass base_transform_class;
+  GstGLFilterProcessFunc filter;
 };
 
 GType gst_gl_filter_get_type(void);
diff --git a/sys/glsink/gstglfilterexample.c b/sys/glsink/gstglfilterexample.c
index aa709abc..8f7de08f 100644
--- a/sys/glsink/gstglfilterexample.c
+++ b/sys/glsink/gstglfilterexample.c
@@ -59,24 +59,6 @@ static const GstElementDetails element_details = GST_ELEMENT_DETAILS ("FIXME",
     "FIXME example filter",
     "FIXME <fixme@fixme.com>");
 
-#if 0
-#define GST_GL_VIDEO_CAPS "video/x-raw-gl"
-
-static GstStaticPadTemplate gst_gl_filter_example_src_pad_template =
-GST_STATIC_PAD_TEMPLATE ("src",
-    GST_PAD_SRC,
-    GST_PAD_ALWAYS,
-    GST_STATIC_CAPS (GST_GL_VIDEO_CAPS)
-    );
-
-static GstStaticPadTemplate gst_gl_filter_example_sink_pad_template =
-GST_STATIC_PAD_TEMPLATE ("sink",
-    GST_PAD_SINK,
-    GST_PAD_ALWAYS,
-    GST_STATIC_CAPS (GST_GL_VIDEO_CAPS)
-    );
-#endif
-
 enum
 {
   PROP_0
@@ -93,11 +75,8 @@ static void gst_gl_filter_example_set_property (GObject * object, guint prop_id,
 static void gst_gl_filter_example_get_property (GObject * object, guint prop_id,
     GValue * value, GParamSpec * pspec);
 
-static void gst_gl_filter_example_reset (GstGLFilterExample * filter);
-static gboolean gst_gl_filter_example_transform (GstGLFilter * filter,
-    GstGLBuffer * outbuf, GstGLBuffer * inbuf);
-static gboolean gst_gl_filter_example_start (GstGLFilter * filter);
-static gboolean gst_gl_filter_example_stop (GstGLFilter * filter);
+static gboolean gst_gl_filter_example_filter (GstGLFilter * filter,
+    GstGLBuffer * inbuf, GstGLBuffer * outbuf);
 
 
 static void
@@ -106,13 +85,6 @@ gst_gl_filter_example_base_init (gpointer klass)
   GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
 
   gst_element_class_set_details (element_class, &element_details);
-
-#if 0
-  gst_element_class_add_pad_template (element_class,
-      gst_static_pad_template_get (&gst_gl_filter_example_src_pad_template));
-  gst_element_class_add_pad_template (element_class,
-      gst_static_pad_template_get (&gst_gl_filter_example_sink_pad_template));
-#endif
 }
 
 static void
@@ -124,16 +96,13 @@ gst_gl_filter_example_class_init (GstGLFilterExampleClass * klass)
   gobject_class->set_property = gst_gl_filter_example_set_property;
   gobject_class->get_property = gst_gl_filter_example_get_property;
 
-  GST_GL_FILTER_CLASS (klass)->transform = gst_gl_filter_example_transform;
-  GST_GL_FILTER_CLASS (klass)->start = gst_gl_filter_example_start;
-  GST_GL_FILTER_CLASS (klass)->stop = gst_gl_filter_example_stop;
+  GST_GL_FILTER_CLASS (klass)->filter = gst_gl_filter_example_filter;
 }
 
 static void
 gst_gl_filter_example_init (GstGLFilterExample * filter,
     GstGLFilterExampleClass * klass)
 {
-  gst_gl_filter_example_reset (filter);
 }
 
 static void
@@ -162,32 +131,9 @@ gst_gl_filter_example_get_property (GObject * object, guint prop_id,
   }
 }
 
-static void
-gst_gl_filter_example_reset (GstGLFilterExample * filter)
-{
-
-}
-
-static gboolean
-gst_gl_filter_example_start (GstGLFilter * _filter)
-{
-  //GstGLFilterExample *filter = GST_GL_FILTER_EXAMPLE(_filter);
-
-  return TRUE;
-}
-
-static gboolean
-gst_gl_filter_example_stop (GstGLFilter * _filter)
-{
-  GstGLFilterExample *filter = GST_GL_FILTER_EXAMPLE (_filter);
-
-  gst_gl_filter_example_reset (filter);
-  return TRUE;
-}
-
 static gboolean
-gst_gl_filter_example_transform (GstGLFilter * filter, GstGLBuffer * outbuf,
-    GstGLBuffer * inbuf)
+gst_gl_filter_example_filter (GstGLFilter * filter, GstGLBuffer * inbuf,
+    GstGLBuffer * outbuf)
 {
   //GstGLFilterExample *example = GST_GL_FILTER_EXAMPLE(filter);
   int i, j;
diff --git a/sys/glsink/gstgltestsrc.c b/sys/glsink/gstgltestsrc.c
index 563f3c5f..0a9149b4 100644
--- a/sys/glsink/gstgltestsrc.c
+++ b/sys/glsink/gstgltestsrc.c
@@ -520,8 +520,7 @@ gst_gl_test_src_create (GstPushSrc * psrc, GstBuffer ** buffer)
   GST_LOG_OBJECT (src, "creating buffer %dx%d image for frame %d",
       src->width, src->height, (gint) src->n_frames);
 
-  outbuf = gst_gl_buffer_new (src->display, GST_GL_BUFFER_FORMAT_RGB,
-      src->width, src->height);
+  outbuf = gst_gl_buffer_new (src->display, src->width, src->height);
   gst_buffer_set_caps (GST_BUFFER (outbuf),
       GST_PAD_CAPS (GST_BASE_SRC_PAD (psrc)));
 
@@ -540,6 +539,7 @@ gst_gl_test_src_create (GstPushSrc * psrc, GstBuffer ** buffer)
       GL_FRAMEBUFFER_COMPLETE_EXT);
 
   glViewport (0, 0, outbuf->width, outbuf->height);
+  gst_gl_display_check_error (outbuf->display, __LINE__);
 
 #if 0
   glClearColor (0.3, 0.3, 0.3, 1.0);
@@ -556,8 +556,10 @@ gst_gl_test_src_create (GstPushSrc * psrc, GstBuffer ** buffer)
   }
 
   glFlush ();
+  gst_gl_display_check_error (outbuf->display, __LINE__);
 
   glDeleteFramebuffersEXT (1, &fbo);
+  gst_gl_display_check_error (outbuf->display, __LINE__);
 
   gst_gl_display_unlock (outbuf->display);
 
diff --git a/sys/glsink/gstglupload.c b/sys/glsink/gstglupload.c
index 2405d61f..036fe55f 100644
--- a/sys/glsink/gstglupload.c
+++ b/sys/glsink/gstglupload.c
@@ -23,6 +23,7 @@
 #endif
 
 #include <gst/gst.h>
+#include <gst/base/gstbasetransform.h>
 #include <gst/video/video.h>
 #include <gstglbuffer.h>
 
@@ -42,7 +43,7 @@ typedef void (*GstGLUploadProcessFunc) (GstGLUpload *, guint8 *, guint);
 
 struct _GstGLUpload
 {
-  GstElement element;
+  GstBaseTransform base_transform;
 
   GstPad *srcpad;
   GstPad *sinkpad;
@@ -60,7 +61,7 @@ struct _GstGLUpload
 
 struct _GstGLUploadClass
 {
-  GstElementClass element_class;
+  GstBaseTransformClass base_transform_class;
 };
 
 static const GstElementDetails element_details = GST_ELEMENT_DETAILS ("FIXME",
@@ -94,19 +95,29 @@ enum
 #define DEBUG_INIT(bla) \
   GST_DEBUG_CATEGORY_INIT (gst_gl_upload_debug, "glupload", 0, "glupload element");
 
-GST_BOILERPLATE_FULL (GstGLUpload, gst_gl_upload, GstElement,
-    GST_TYPE_ELEMENT, DEBUG_INIT);
+GST_BOILERPLATE_FULL (GstGLUpload, gst_gl_upload, GstBaseTransform,
+    GST_TYPE_BASE_TRANSFORM, DEBUG_INIT);
 
 static void gst_gl_upload_set_property (GObject * object, guint prop_id,
     const GValue * value, GParamSpec * pspec);
 static void gst_gl_upload_get_property (GObject * object, guint prop_id,
     GValue * value, GParamSpec * pspec);
 
-static GstFlowReturn gst_gl_upload_chain (GstPad * pad, GstBuffer * buf);
 static void gst_gl_upload_reset (GstGLUpload * upload);
-static GstStateChangeReturn
-gst_gl_upload_change_state (GstElement * element, GstStateChange transition);
-static gboolean gst_gl_upload_sink_setcaps (GstPad * pad, GstCaps * caps);
+
+static void gst_gl_upload_reset (GstGLUpload * upload);
+static gboolean gst_gl_upload_set_caps (GstBaseTransform * bt,
+    GstCaps * incaps, GstCaps * outcaps);
+static GstCaps *gst_gl_upload_transform_caps (GstBaseTransform * bt,
+    GstPadDirection direction, GstCaps * caps);
+static gboolean gst_gl_upload_start (GstBaseTransform * bt);
+static gboolean gst_gl_upload_stop (GstBaseTransform * bt);
+static GstFlowReturn gst_gl_upload_prepare_output_buffer (GstBaseTransform *
+    trans, GstBuffer * input, gint size, GstCaps * caps, GstBuffer ** buf);
+static GstFlowReturn gst_gl_upload_transform (GstBaseTransform * trans,
+    GstBuffer * inbuf, GstBuffer * outbuf);
+static gboolean gst_gl_upload_get_unit_size (GstBaseTransform * trans,
+    GstCaps * caps, guint * size);
 
 
 static void
@@ -131,19 +142,20 @@ gst_gl_upload_class_init (GstGLUploadClass * klass)
   gobject_class->set_property = gst_gl_upload_set_property;
   gobject_class->get_property = gst_gl_upload_get_property;
 
-  GST_ELEMENT_CLASS (klass)->change_state = gst_gl_upload_change_state;
+  GST_BASE_TRANSFORM_CLASS (klass)->transform_caps =
+      gst_gl_upload_transform_caps;
+  GST_BASE_TRANSFORM_CLASS (klass)->transform = gst_gl_upload_transform;
+  GST_BASE_TRANSFORM_CLASS (klass)->start = gst_gl_upload_start;
+  GST_BASE_TRANSFORM_CLASS (klass)->stop = gst_gl_upload_stop;
+  GST_BASE_TRANSFORM_CLASS (klass)->set_caps = gst_gl_upload_set_caps;
+  GST_BASE_TRANSFORM_CLASS (klass)->get_unit_size = gst_gl_upload_get_unit_size;
+  GST_BASE_TRANSFORM_CLASS (klass)->prepare_output_buffer =
+      gst_gl_upload_prepare_output_buffer;
 }
 
 static void
 gst_gl_upload_init (GstGLUpload * upload, GstGLUploadClass * klass)
 {
-  gst_element_create_all_pads (GST_ELEMENT (upload));
-
-  upload->sinkpad = gst_element_get_static_pad (GST_ELEMENT (upload), "sink");
-  upload->srcpad = gst_element_get_static_pad (GST_ELEMENT (upload), "src");
-
-  gst_pad_set_setcaps_function (upload->sinkpad, gst_gl_upload_sink_setcaps);
-  gst_pad_set_chain_function (upload->sinkpad, gst_gl_upload_chain);
 
   gst_gl_upload_reset (upload);
 }
@@ -186,25 +198,30 @@ gst_gl_upload_reset (GstGLUpload * upload)
 }
 
 static gboolean
-gst_gl_upload_start (GstGLUpload * upload)
+gst_gl_upload_start (GstBaseTransform * bt)
 {
+  GstGLUpload *upload = GST_GL_UPLOAD (bt);
   gboolean ret;
 
   upload->format = GST_GL_BUFFER_FORMAT_RGB;
   upload->display = gst_gl_display_new ();
   ret = gst_gl_display_connect (upload->display, NULL);
+  //upload->format = GST_VIDEO_FORMAT_RGBx;
 
-  return ret;
+  return TRUE;
 }
 
 static gboolean
-gst_gl_upload_stop (GstGLUpload * upload)
+gst_gl_upload_stop (GstBaseTransform * bt)
 {
+  GstGLUpload *upload = GST_GL_UPLOAD (bt);
+
   gst_gl_upload_reset (upload);
 
   return TRUE;
 }
 
+#if 0
 static gboolean
 gst_gl_upload_sink_setcaps (GstPad * pad, GstCaps * caps)
 {
@@ -246,7 +263,9 @@ gst_gl_upload_sink_setcaps (GstPad * pad, GstCaps * caps)
 
   return ret;
 }
+#endif
 
+#if 0
 static GstFlowReturn
 gst_gl_upload_chain (GstPad * pad, GstBuffer * buf)
 {
@@ -277,44 +296,142 @@ gst_gl_upload_chain (GstPad * pad, GstBuffer * buf)
   gst_object_unref (upload);
   return GST_FLOW_OK;
 }
+#endif
 
-static GstStateChangeReturn
-gst_gl_upload_change_state (GstElement * element, GstStateChange transition)
+static GstCaps *
+gst_gl_upload_transform_caps (GstBaseTransform * bt,
+    GstPadDirection direction, GstCaps * caps)
 {
   GstGLUpload *upload;
-  GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
+  GstStructure *structure;
+  GstCaps *newcaps;
+  GstStructure *newstruct;
+  const GValue *width_value;
+  const GValue *height_value;
+  const GValue *framerate_value;
+  const GValue *par_value;
+
+  upload = GST_GL_UPLOAD (bt);
+
+  GST_ERROR ("transform caps %" GST_PTR_FORMAT, caps);
+
+  structure = gst_caps_get_structure (caps, 0);
+
+  width_value = gst_structure_get_value (structure, "width");
+  height_value = gst_structure_get_value (structure, "height");
+  framerate_value = gst_structure_get_value (structure, "framerate");
+  par_value = gst_structure_get_value (structure, "pixel-aspect-ratio");
+
+  if (direction == GST_PAD_SRC) {
+    newcaps = gst_caps_new_simple ("video/x-raw-rgb", NULL);
+  } else {
+    newcaps = gst_caps_new_simple ("video/x-raw-gl",
+        "format", G_TYPE_INT, GST_GL_BUFFER_FORMAT_RGBA,
+        "is_yuv", G_TYPE_BOOLEAN, FALSE, NULL);
+  }
+  newstruct = gst_caps_get_structure (newcaps, 0);
+  gst_structure_set_value (newstruct, "width", width_value);
+  gst_structure_set_value (newstruct, "height", height_value);
+  gst_structure_set_value (newstruct, "framerate", framerate_value);
+  if (par_value) {
+    gst_structure_set_value (newstruct, "pixel-aspect-ratio", par_value);
+  } else {
+    gst_structure_set (newstruct, "pixel-aspect-ratio", GST_TYPE_FRACTION,
+        1, 1, NULL);
+  }
 
-  GST_DEBUG ("change state");
+  GST_ERROR ("new caps %" GST_PTR_FORMAT, newcaps);
 
-  upload = GST_GL_UPLOAD (element);
+  return newcaps;
+}
 
-  switch (transition) {
-    case GST_STATE_CHANGE_NULL_TO_READY:
-      break;
-    case GST_STATE_CHANGE_READY_TO_PAUSED:
-      gst_gl_upload_start (upload);
-      break;
-    case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
-      break;
-    default:
-      break;
-  }
+static gboolean
+gst_gl_upload_set_caps (GstBaseTransform * bt, GstCaps * incaps,
+    GstCaps * outcaps)
+{
+  GstGLUpload *upload;
+  gboolean ret;
 
-  ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
-  if (ret == GST_STATE_CHANGE_FAILURE)
-    return ret;
+  upload = GST_GL_UPLOAD (bt);
 
-  switch (transition) {
-    case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
-      break;
-    case GST_STATE_CHANGE_PAUSED_TO_READY:
-      gst_gl_upload_stop (upload);
-      break;
-    case GST_STATE_CHANGE_READY_TO_NULL:
-      break;
-    default:
-      break;
+  GST_DEBUG ("called with %" GST_PTR_FORMAT, incaps);
+
+  ret = gst_video_format_parse_caps (incaps, &upload->video_format,
+      &upload->width, &upload->height);
+
+  if (!ret) {
+    GST_DEBUG ("bad caps");
+    return FALSE;
   }
 
   return ret;
 }
+
+static gboolean
+gst_gl_upload_get_unit_size (GstBaseTransform * trans, GstCaps * caps,
+    guint * size)
+{
+  gboolean ret;
+  GstStructure *structure;
+  int width;
+  int height;
+
+  structure = gst_caps_get_structure (caps, 0);
+  if (gst_structure_has_name (structure, "video/x-raw-gl")) {
+    GstGLBufferFormat format;
+
+    ret = gst_gl_buffer_format_parse_caps (caps, &format, &width, &height);
+    if (ret) {
+      *size = gst_gl_buffer_format_get_size (format, width, height);
+    }
+  } else {
+    GstVideoFormat format;
+
+    ret = gst_video_format_parse_caps (caps, &format, &width, &height);
+    if (ret) {
+      *size = gst_video_format_get_size (format, width, height);
+    }
+  }
+
+  return TRUE;
+}
+
+static GstFlowReturn
+gst_gl_upload_prepare_output_buffer (GstBaseTransform * trans,
+    GstBuffer * input, gint size, GstCaps * caps, GstBuffer ** buf)
+{
+  GstGLUpload *upload;
+  GstGLBuffer *gl_outbuf;
+
+  upload = GST_GL_UPLOAD (trans);
+
+  gl_outbuf = gst_gl_buffer_new_from_video_format (upload->display,
+      upload->video_format, upload->width, upload->height);
+
+  *buf = GST_BUFFER (gl_outbuf);
+  gst_buffer_set_caps (*buf, caps);
+
+  return GST_FLOW_OK;
+}
+
+static GstFlowReturn
+gst_gl_upload_transform (GstBaseTransform * trans, GstBuffer * inbuf,
+    GstBuffer * outbuf)
+{
+  GstGLUpload *upload;
+  GstGLBuffer *gl_outbuf = GST_GL_BUFFER (outbuf);
+
+  upload = GST_GL_UPLOAD (trans);
+
+  GST_DEBUG ("uploading %p size %d",
+      GST_BUFFER_DATA (inbuf), GST_BUFFER_SIZE (inbuf));
+  gst_gl_buffer_upload (gl_outbuf, upload->video_format,
+      GST_BUFFER_DATA (inbuf));
+
+  if (upload->peek) {
+    gst_gl_display_draw_texture (gl_outbuf->display, gl_outbuf->texture,
+        gl_outbuf->width, gl_outbuf->height);
+  }
+
+  return GST_FLOW_OK;
+}