static GstCaps *
gst_v4l2sink_get_caps (GstBaseSink * bsink)
{
GstV4l2Sink *v4l2sink = GST_V4L2SINK (bsink);
GstCaps *ret;
GSList *walk;
GSList *formats;
if (!GST_V4L2_IS_OPEN (v4l2sink->v4l2object)) {
/* FIXME: copy? */
GST_DEBUG_OBJECT (v4l2sink, "device is not open");
return
gst_caps_copy (gst_pad_get_pad_template_caps (GST_BASE_SINK_PAD
(v4l2sink)));
}
if (v4l2sink->probed_caps) {
LOG_CAPS (v4l2sink, v4l2sink->probed_caps);
return gst_caps_ref (v4l2sink->probed_caps);
}
formats = gst_v4l2_object_get_format_list (v4l2sink->v4l2object);
ret = gst_caps_new_empty ();
for (walk = v4l2sink->v4l2object->formats; walk; walk = walk->next) {
struct v4l2_fmtdesc *format;
GstStructure *template;
static gboolean
gst_v4l2sink_set_caps (GstBaseSink * bsink, GstCaps * caps)
{
GstV4l2Sink *v4l2sink = GST_V4L2SINK (bsink);
GstV4l2Object *obj = v4l2sink->v4l2object;
LOG_CAPS (v4l2sink, caps);
if (!GST_V4L2_IS_OPEN (v4l2sink->v4l2object)) {
GST_DEBUG_OBJECT (v4l2sink, "device is not open");
return FALSE;
}
/* make sure the caps changed before doing anything */
if (gst_v4l2_object_caps_equal (obj, caps))
return TRUE;
if (!gst_v4l2_object_stop (obj))
goto stop_failed;
if (!gst_v4l2_object_set_format (v4l2sink->v4l2object, caps))
goto invalid_format;
gst_v4l2sink_sync_overlay_fields (v4l2sink);
gst_v4l2sink_sync_crop_fields (v4l2sink);
#ifdef HAVE_XVIDEO
gst_v4l2_video_overlay_prepare_window_handle (v4l2sink->v4l2object, TRUE);
#endif
GST_INFO_OBJECT (v4l2sink, "outputting buffers via mmap()");
v4l2sink->video_width = GST_V4L2_WIDTH (v4l2sink->v4l2object);
v4l2sink->video_height = GST_V4L2_HEIGHT (v4l2sink->v4l2object);
/* TODO: videosink width/height should be scaled according to
* pixel-aspect-ratio
*/
GST_VIDEO_SINK_WIDTH (v4l2sink) = v4l2sink->video_width;
GST_VIDEO_SINK_HEIGHT (v4l2sink) = v4l2sink->video_height;
return TRUE;
/* ERRORS */
stop_failed:
{
GST_DEBUG_OBJECT (v4l2sink, "failed to stop streaming");
return FALSE;
}
invalid_format:
{
/* error already posted */
GST_DEBUG_OBJECT (v4l2sink, "can't set format");
return FALSE;
}
}
static gboolean
gst_v4l2src_negotiate (GstBaseSrc * basesrc)
{
GstV4l2Src *v4l2src;
GstV4l2Object *obj;
GstCaps *thiscaps;
GstCaps *caps = NULL;
GstCaps *peercaps = NULL;
gboolean result = FALSE;
v4l2src = GST_V4L2SRC (basesrc);
obj = v4l2src->v4l2object;
/* We don't allow renegotiation, just return TRUE in that case */
if (GST_V4L2_IS_ACTIVE (obj))
return TRUE;
/* first see what is possible on our source pad */
thiscaps = gst_pad_query_caps (GST_BASE_SRC_PAD (basesrc), NULL);
GST_DEBUG_OBJECT (basesrc, "caps of src: %" GST_PTR_FORMAT, thiscaps);
LOG_CAPS (basesrc, thiscaps);
/* nothing or anything is allowed, we're done */
if (thiscaps == NULL || gst_caps_is_any (thiscaps))
goto no_nego_needed;
/* get the peer caps without a filter as we'll filter ourselves later on */
peercaps = gst_pad_peer_query_caps (GST_BASE_SRC_PAD (basesrc), NULL);
GST_DEBUG_OBJECT (basesrc, "caps of peer: %" GST_PTR_FORMAT, peercaps);
LOG_CAPS (basesrc, peercaps);
if (peercaps && !gst_caps_is_any (peercaps)) {
GstCaps *icaps = NULL;
int i;
/* Prefer the first caps we are compatible with that the peer proposed */
for (i = 0; i < gst_caps_get_size (peercaps); i++) {
/* get intersection */
GstCaps *ipcaps = gst_caps_copy_nth (peercaps, i);
GST_DEBUG_OBJECT (basesrc, "peer: %" GST_PTR_FORMAT, ipcaps);
LOG_CAPS (basesrc, ipcaps);
icaps = gst_caps_intersect (thiscaps, ipcaps);
gst_caps_unref (ipcaps);
if (!gst_caps_is_empty (icaps))
break;
gst_caps_unref (icaps);
icaps = NULL;
}
GST_DEBUG_OBJECT (basesrc, "intersect: %" GST_PTR_FORMAT, icaps);
LOG_CAPS (basesrc, icaps);
if (icaps) {
/* If there are multiple intersections pick the one with the smallest
* resolution strictly bigger then the first peer caps */
if (gst_caps_get_size (icaps) > 1) {
GstStructure *s = gst_caps_get_structure (peercaps, 0);
int best = 0;
int twidth, theight;
int width = G_MAXINT, height = G_MAXINT;
if (gst_structure_get_int (s, "width", &twidth)
&& gst_structure_get_int (s, "height", &theight)) {
/* Walk the structure backwards to get the first entry of the
* smallest resolution bigger (or equal to) the preferred resolution)
*/
for (i = gst_caps_get_size (icaps) - 1; i >= 0; i--) {
GstStructure *is = gst_caps_get_structure (icaps, i);
int w, h;
if (gst_structure_get_int (is, "width", &w)
&& gst_structure_get_int (is, "height", &h)) {
if (w >= twidth && w <= width && h >= theight && h <= height) {
width = w;
height = h;
best = i;
}
}
}
}
caps = gst_caps_copy_nth (icaps, best);
gst_caps_unref (icaps);
} else {
caps = icaps;
}
}
gst_caps_unref (thiscaps);
} else {
/* no peer or peer have ANY caps, work with our own caps then */
caps = thiscaps;
}
if (peercaps)
gst_caps_unref (peercaps);
if (caps) {
caps = gst_caps_truncate (caps);
/* now fixate */
if (!gst_caps_is_empty (caps)) {
caps = gst_v4l2src_fixate (basesrc, caps);
GST_DEBUG_OBJECT (basesrc, "fixated to: %" GST_PTR_FORMAT, caps);
LOG_CAPS (basesrc, caps);
if (gst_caps_is_any (caps)) {
/* hmm, still anything, so element can do anything and
* nego is not needed */
result = TRUE;
} else if (gst_caps_is_fixed (caps)) {
/* yay, fixed caps, use those then */
result = gst_base_src_set_caps (basesrc, caps);
}
}
gst_caps_unref (caps);
}
return result;
no_nego_needed:
{
GST_DEBUG_OBJECT (basesrc, "no negotiation needed");
if (thiscaps)
gst_caps_unref (thiscaps);
return TRUE;
}
}
