[Spice-devel] [PATCH spice-gtk v4 6/7] display-gst: Use Playbin for GStreamer 1.9.0 onwards
Victor Toso
victortoso at redhat.com
Wed Jun 28 12:43:03 UTC 2017
From: Victor Toso <me at victortoso.com>
The Playbin can provide the full pipeline which reduces the
overall maintenance in the code as we don't need to track which
decoder can work with our stream type.
We need to maintain the GstCaps per SPICE_VIDEO_CODEC_TYPE in order to
tell Playbin the type of data we expect. This much should be covered
by spice-protocol and very likely we will need to extend it in the
future to allow more settings that might not possible to verify at
runtime.
This patch keeps previous code for compatibility reasons.
Note that we have to wait Playbin to emit "source-setup" in order to
configure GstAppSrc with the capabilities of input stream. If in the
unlikely event of frames arriving while GstAppSrc is not setup, we
will drop those frames.
Signed-off-by: Victor Toso <victortoso at redhat.com>
Signed-off-by: Victor Toso <me at victortoso.com>
---
src/channel-display-gst.c | 99 ++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 97 insertions(+), 2 deletions(-)
diff --git a/src/channel-display-gst.c b/src/channel-display-gst.c
index 1b40002..df58de3 100644
--- a/src/channel-display-gst.c
+++ b/src/channel-display-gst.c
@@ -50,6 +50,9 @@ typedef struct SpiceGstDecoder {
guint timer_id;
} SpiceGstDecoder;
+/* FIXME: With gstreamer version 1.9.0 and higher, we are using playbin to
+ * create the pipeline for us and for that reason we don't need to keep track of
+ * decoder's name anymore. */
static struct {
const gchar *dec_name;
const gchar *dec_caps;
@@ -83,6 +86,21 @@ G_STATIC_ASSERT(G_N_ELEMENTS(gst_opts) <= SPICE_VIDEO_CODEC_TYPE_ENUM_END);
#define VALID_VIDEO_CODEC_TYPE(codec) \
(codec > 0 && codec < G_N_ELEMENTS(gst_opts))
+typedef enum {
+ GST_PLAY_FLAG_VIDEO = (1 << 0),
+ GST_PLAY_FLAG_AUDIO = (1 << 1),
+ GST_PLAY_FLAG_TEXT = (1 << 2),
+ GST_PLAY_FLAG_VIS = (1 << 3),
+ GST_PLAY_FLAG_SOFT_VOLUME = (1 << 4),
+ GST_PLAY_FLAG_NATIVE_AUDIO = (1 << 5),
+ GST_PLAY_FLAG_NATIVE_VIDEO = (1 << 6),
+ GST_PLAY_FLAG_DOWNLOAD = (1 << 7),
+ GST_PLAY_FLAG_BUFFERING = (1 << 8),
+ GST_PLAY_FLAG_DEINTERLACE = (1 << 9),
+ GST_PLAY_FLAG_SOFT_COLORBALANCE = (1 << 10),
+ GST_PLAY_FLAG_FORCE_FILTERS = (1 << 11),
+} GstPlayFlags;
+
/* ---------- SpiceGstFrame ---------- */
typedef struct SpiceGstFrame {
@@ -298,13 +316,81 @@ static gboolean handle_pipeline_message(GstBus *bus, GstMessage *msg, gpointer v
return TRUE;
}
+#if GST_CHECK_VERSION(1,9,0)
+static void app_source_setup(GstElement *pipeline G_GNUC_UNUSED,
+ GstElement *source,
+ SpiceGstDecoder *decoder)
+{
+ GstCaps *caps;
+
+ /* - We schedule the frame display ourselves so set sync=false on appsink
+ * so the pipeline decodes them as fast as possible. This will also
+ * minimize the risk of frames getting lost when we rebuild the
+ * pipeline.
+ * - Set max-bytes=0 on appsrc so it does not drop frames that may be
+ * needed by those that follow.
+ */
+ caps = gst_caps_from_string(gst_opts[decoder->base.codec_type].dec_caps);
+ g_object_set(source,
+ "caps", caps,
+ "is-live", TRUE,
+ "format", GST_FORMAT_TIME,
+ "max-bytes", 0,
+ "block", TRUE,
+ NULL);
+ gst_caps_unref(caps);
+ decoder->appsrc = GST_APP_SRC(gst_object_ref(source));
+}
+#endif
+
static gboolean create_pipeline(SpiceGstDecoder *decoder)
{
- gchar *desc;
GstAppSinkCallbacks appsink_cbs = { NULL };
- GError *err = NULL;
GstBus *bus;
+#if GST_CHECK_VERSION(1,9,0)
+ GstElement *playbin, *sink;
+ gint flags;
+ GstCaps *caps;
+ playbin = gst_element_factory_make("playbin", "playbin");
+ if (playbin == NULL) {
+ spice_warning("error upon creation of 'playbin' element");
+ return FALSE;
+ }
+
+ sink = gst_element_factory_make("appsink", "sink");
+ if (sink == NULL) {
+ spice_warning("error upon creation of 'appsink' element");
+ gst_object_unref(playbin);
+ return FALSE;
+ }
+
+ caps = gst_caps_from_string("video/x-raw,format=BGRx");
+ g_object_set(sink,
+ "caps", caps,
+ "sync", FALSE,
+ "drop", FALSE,
+ NULL);
+ gst_caps_unref(caps);
+
+ g_signal_connect(playbin, "source-setup", G_CALLBACK(app_source_setup), decoder);
+
+ g_object_set(playbin,
+ "uri", "appsrc://",
+ "video-sink", gst_object_ref(sink),
+ NULL);
+
+ /* Disable audio in playbin */
+ g_object_get(playbin, "flags", &flags, NULL);
+ flags &= ~(GST_PLAY_FLAG_AUDIO | GST_PLAY_FLAG_TEXT);
+ g_object_set(playbin, "flags", flags, NULL);
+
+ g_warn_if_fail(decoder->appsrc == NULL);
+ decoder->appsink = GST_APP_SINK(sink);
+ decoder->pipeline = playbin;
+#else
+ gchar *desc;
+ GError *err = NULL;
/* - We schedule the frame display ourselves so set sync=false on appsink
* so the pipeline decodes them as fast as possible. This will also
@@ -330,6 +416,7 @@ static gboolean create_pipeline(SpiceGstDecoder *decoder)
decoder->appsrc = GST_APP_SRC(gst_bin_get_by_name(GST_BIN(decoder->pipeline), "src"));
decoder->appsink = GST_APP_SINK(gst_bin_get_by_name(GST_BIN(decoder->pipeline), "sink"));
+#endif
appsink_cbs.new_sample = new_sample;
gst_app_sink_set_callbacks(decoder->appsink, &appsink_cbs, decoder, NULL);
@@ -457,6 +544,14 @@ static gboolean spice_gst_decoder_queue_frame(VideoDecoder *video_decoder,
return FALSE;
}
+#if GST_CHECK_VERSION(1,9,0)
+ if (decoder->appsrc == NULL) {
+ spice_warning("Error: Playbin has not yet initialized the Appsrc element");
+ stream_dropped_frame_on_playback(decoder->base.stream);
+ return TRUE;
+ }
+#endif
+
/* ref() the frame data for the buffer */
frame->ref_data(frame->data_opaque);
GstBuffer *buffer = gst_buffer_new_wrapped_full(GST_MEMORY_FLAG_PHYSICALLY_CONTIGUOUS,
--
2.13.0
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