[Spice-devel,v5,17/20] spice-gtk: Add a GStreamer video decoder with support for MJPEG, VP8 and h264.

Submitted by Francois Gouget on Aug. 27, 2015, 7:03 p.m.

Details

Message ID alpine.DEB.2.20.1508272042270.22172@amboise
State New
Headers show

Not browsing as part of any series.

Commit Message

Francois Gouget Aug. 27, 2015, 7:03 p.m.
Based on a patch by Jeremy White.

Signed-off-by: Francois Gouget <fgouget@codeweavers.com>
---

***WARNNIG*** This is the first client patch that needs the protocol
              constants defined in patch 01.

Changes since take 2:
 - None.


 configure.ac               |  47 +++++++---
 src/Makefile.am            |  12 ++-
 src/channel-display-gst.c  | 216 +++++++++++++++++++++++++++++++++++++++++++++
 src/channel-display-priv.h |   1 +
 src/channel-display.c      |   6 +-
 5 files changed, 265 insertions(+), 17 deletions(-)
 create mode 100644 src/channel-display-gst.c

Patch hide | download patch | download mbox

diff --git a/configure.ac b/configure.ac
index 0a60ec3..8ee71ca 100644
--- a/configure.ac
+++ b/configure.ac
@@ -301,7 +301,7 @@  AC_ARG_WITH([audio],
 
 case "$with_audio" in
   gstreamer|pulse|auto*)
-    PKG_CHECK_MODULES(GST, gstreamer-1.0 gstreamer-base-1.0 gstreamer-app-1.0 gstreamer-audio-1.0, [have_gst=yes], [have_gst=no])
+    PKG_CHECK_MODULES(GSTAUDIO, gstreamer-1.0 gstreamer-base-1.0 gstreamer-app-1.0 gstreamer-audio-1.0, [have_gst_audio=yes], [have_gst_audio=no])
     PKG_CHECK_MODULES(PULSE, libpulse libpulse-mainloop-glib, [have_pulse=yes], [have_pulse=no])
     ;;
   no*)
@@ -312,7 +312,7 @@  esac
 AS_IF([test "x$with_audio" = "xauto" && test "x$have_pulse" = "xyes"],
       [with_audio=pulse])
 
-AS_IF([test "x$with_audio" = "xauto" && test "x$have_gst" = "xyes"],
+AS_IF([test "x$with_audio" = "xauto" && test "x$have_gst_audio" = "xyes"],
       [with_audio=gstreamer])
 
 AS_IF([test "x$with_audio" = "xauto"],
@@ -321,22 +321,41 @@  AS_IF([test "x$with_audio" = "xauto"],
 AS_IF([test "x$with_audio" = "xpulse"],
       [AS_IF([test "x$have_pulse" = "xyes"],
              [AC_DEFINE([WITH_PULSE], 1, [Have pulseaudio?])],
-             [AC_MSG_ERROR([PulseAudio requested but not found])
-      ])
-])
+             [AC_MSG_ERROR([PulseAudio requested but not found])]
+      )]
+)
 AM_CONDITIONAL([WITH_PULSE], [test "x$have_pulse" = "xyes"])
 AC_SUBST(PULSE_CFLAGS)
 AC_SUBST(PULSE_LIBS)
 
 AS_IF([test "x$with_audio" = "xgstreamer"],
-      [AS_IF([test "x$have_gst" = "xyes"],
-             [AC_DEFINE([WITH_GSTAUDIO], 1, [Have GStreamer 1.0?])],
-             [AC_MSG_ERROR([GStreamer 1.0 requested but not found])
-      ])
-])
-AM_CONDITIONAL([WITH_GSTAUDIO], [test "x$have_gst" = "xyes"])
-AC_SUBST(GST_CFLAGS)
-AC_SUBST(GST_LIBS)
+      [AS_IF([test "x$have_gst_audio" = "xyes"],
+             [AC_DEFINE([WITH_GSTAUDIO], 1, [Have GStreamer 1.0 audio?])],
+             [AC_MSG_ERROR([GStreamer 1.0 audio requested but not found])]
+      )]
+)
+AM_CONDITIONAL([WITH_GSTAUDIO], [test "x$have_gst_audio" = "xyes"])
+AC_SUBST(GSTAUDIO_CFLAGS)
+AC_SUBST(GSTAUDIO_LIBS)
+
+AC_ARG_ENABLE([gst-video],
+              AS_HELP_STRING([--enable-gst-video=@<:@auto/yes/no@:>@],
+                             [Enable GStreamer video support @<:@default=auto@:>@]),
+              [],
+              [enable_gst_video="auto"])
+
+AS_IF([test "x$enable_gst_video" != "xno"],
+      [PKG_CHECK_MODULES(GSTVIDEO, gstreamer-1.0 gstreamer-base-1.0 gstreamer-app-1.0 gstreamer-video-1.0, [have_gst_video=yes], [have_gst_video=no])
+       AS_IF([test "x$have_gst_video" = "xyes"],
+             [AC_DEFINE([HAVE_GSTVIDEO], 1, [Have GStreamer 1.0 video?])],
+             [AS_IF([test "x$enable_gst_video" = "xyes"],
+                    [AC_MSG_ERROR([GStreamer 1.0 video requested but not found])]
+              )]
+       )]
+)
+AM_CONDITIONAL([HAVE_GSTVIDEO], [test "x$have_gst_video" = "xyes"])]
+AC_SUBST(GSTVIDEO_CFLAGS)
+AC_SUBST(GSTVIDEO_LIBS)
 
 AC_CHECK_LIB(jpeg, jpeg_destroy_decompress,
     AC_MSG_CHECKING([for jpeglib.h])
@@ -702,7 +721,7 @@  SPICE_CFLAGS="$SPICE_CFLAGS $WARN_CFLAGS"
 
 AC_SUBST(SPICE_CFLAGS)
 
-SPICE_GLIB_CFLAGS="$PIXMAN_CFLAGS $PULSE_CFLAGS $GST_CFLAGS $GLIB2_CFLAGS $GIO_CFLAGS $GOBJECT2_CFLAGS $SSL_CFLAGS $SASL_CFLAGS"
+SPICE_GLIB_CFLAGS="$PROTOCOL_CFLAGS $PIXMAN_CFLAGS $PULSE_CFLAGS $GSTVIDEO_CFLAGS $GSTAUDIO_CFLAGS $GLIB2_CFLAGS $GIO_CFLAGS $GOBJECT2_CFLAGS $SSL_CFLAGS $SASL_CFLAGS"
 SPICE_GTK_CFLAGS="$SPICE_GLIB_CFLAGS $GTK_CFLAGS "
 
 AC_SUBST(SPICE_GLIB_CFLAGS)
diff --git a/src/Makefile.am b/src/Makefile.am
index cf02198..925c75f 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -96,7 +96,8 @@  SPICE_COMMON_CPPFLAGS =						\
 	$(GOBJECT2_CFLAGS)					\
 	$(SSL_CFLAGS)						\
 	$(SASL_CFLAGS)						\
-	$(GST_CFLAGS)						\
+	$(GSTAUDIO_CFLAGS)					\
+	$(GSTVIDEO_CFLAGS)					\
 	$(SMARTCARD_CFLAGS)					\
 	$(USBREDIR_CFLAGS)					\
 	$(GUDEV_CFLAGS)						\
@@ -207,7 +208,8 @@  libspice_client_glib_2_0_la_LIBADD =					\
 	$(PIXMAN_LIBS)							\
 	$(SSL_LIBS)							\
 	$(PULSE_LIBS)							\
-	$(GST_LIBS)							\
+	$(GSTAUDIO_LIBS)						\
+	$(GSTVIDEO_LIBS)						\
 	$(SASL_LIBS)							\
 	$(SMARTCARD_LIBS)						\
 	$(USBREDIR_LIBS)						\
@@ -340,6 +342,12 @@  libspice_client_glib_2_0_la_SOURCES +=	\
 	$(NULL)
 endif
 
+if HAVE_GSTVIDEO
+libspice_client_glib_2_0_la_SOURCES +=	\
+	channel-display-gst.c		\
+	$(NULL)
+endif
+
 if WITH_PHODAV
 libspice_client_glib_2_0_la_SOURCES +=	\
 	giopipe.c			\
diff --git a/src/channel-display-gst.c b/src/channel-display-gst.c
new file mode 100644
index 0000000..3024356
--- /dev/null
+++ b/src/channel-display-gst.c
@@ -0,0 +1,216 @@ 
+/* -*- Mode: C; c-basic-offset: 4; indent-tabs-mode: nil -*- */
+/*
+   Copyright (C) 2015 CodeWeavers, Inc
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with this library; if not, see <http://www.gnu.org/licenses/>.
+*/
+#include "config.h"
+
+#include "spice-client.h"
+#include "spice-common.h"
+#include "spice-channel-priv.h"
+
+typedef struct GstDecoder GstDecoder;
+#define VIDEO_DECODER_T GstDecoder
+#include "channel-display-priv.h"
+
+#include <gst/gst.h>
+#include <gst/app/gstappsrc.h>
+#include <gst/app/gstappsink.h>
+
+
+/* GStreamer decoder implementation */
+
+struct GstDecoder {
+    VideoDecoder base;
+
+    /* ---------- Video characteristics ---------- */
+
+    int width;
+    int height;
+
+    /* ---------- GStreamer pipeline ---------- */
+
+    GstElement *pipeline;
+    GstAppSrc *appsrc;
+    GstAppSink *appsink;
+
+    /* ---------- Output frame data ---------- */
+
+    GstSample *sample;
+    GstMapInfo mapinfo;
+};
+
+
+/* ---------- GStreamer pipeline ---------- */
+
+static void reset_pipeline(GstDecoder *decoder)
+{
+    if (!decoder->pipeline) {
+        return;
+    }
+
+    gst_element_set_state(decoder->pipeline, GST_STATE_NULL);
+    gst_object_unref(decoder->appsrc);
+    gst_object_unref(decoder->appsink);
+    gst_object_unref(decoder->pipeline);
+    decoder->pipeline = NULL;
+}
+
+static gboolean construct_pipeline(GstDecoder *decoder)
+{
+    const gchar *src_caps, *gstdec_name;
+    switch (decoder->base.codec_type) {
+    case SPICE_VIDEO_CODEC_TYPE_MJPEG:
+        src_caps = "image/jpeg";
+        gstdec_name = "jpegdec";
+        break;
+    case SPICE_VIDEO_CODEC_TYPE_VP8:
+        src_caps = "video/x-vp8";
+        gstdec_name = "vp8dec";
+        break;
+    case SPICE_VIDEO_CODEC_TYPE_H264:
+        src_caps = "video/x-h264";
+        gstdec_name = "h264parse ! avdec_h264";
+        break;
+    default:
+        spice_warning("Unknown codec type %d", decoder->base.codec_type);
+        return -1;
+    }
+
+    GError *err = NULL;
+    gchar *desc = g_strdup_printf("appsrc name=src format=2 do-timestamp=1 caps=%s ! %s ! videoconvert ! appsink name=sink caps=video/x-raw,format=BGRx", src_caps, gstdec_name);
+    SPICE_DEBUG("GStreamer pipeline: %s", desc);
+    decoder->pipeline = gst_parse_launch_full(desc, NULL, GST_PARSE_FLAG_FATAL_ERRORS, &err);
+    g_free(desc);
+    if (!decoder->pipeline) {
+        spice_warning("GStreamer error: %s", err->message);
+        g_clear_error(&err);
+        return FALSE;
+    }
+
+    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"));
+
+    if (gst_element_set_state(decoder->pipeline, GST_STATE_PLAYING) == GST_STATE_CHANGE_FAILURE) {
+        SPICE_DEBUG("GStreamer error: Unable to set the pipeline to the playing state.");
+        reset_pipeline(decoder);
+        return FALSE;
+    }
+
+    return TRUE;
+}
+
+static gboolean push_compressed_buffer(GstDecoder *decoder,
+                                       SpiceMsgIn *frame_msg)
+{
+    uint8_t *data;
+    uint32_t size = spice_msg_in_frame_data(frame_msg, &data);
+    if (size == 0) {
+        SPICE_DEBUG("got an empty frame buffer!");
+        return FALSE;
+    }
+
+    // TODO.  Grr.  Seems like a wasted alloc
+    gpointer d = g_malloc(size);
+    memcpy(d, data, size);
+    GstBuffer *buffer = gst_buffer_new_wrapped(d, size);
+
+    if (gst_app_src_push_buffer(decoder->appsrc, buffer) != GST_FLOW_OK) {
+        SPICE_DEBUG("GStreamer error: unable to push frame of size %d", size);
+        return FALSE;
+    }
+
+    return TRUE;
+}
+
+static void release_last_frame(GstDecoder *decoder)
+{
+    if (decoder->mapinfo.memory) {
+        gst_memory_unmap(decoder->mapinfo.memory, &decoder->mapinfo);
+        gst_memory_unref(decoder->mapinfo.memory);
+        decoder->mapinfo.memory = NULL;
+    }
+    if (decoder->sample) {
+        gst_sample_unref(decoder->sample);
+        decoder->sample = NULL;
+    }
+}
+
+static uint8_t* pull_raw_frame(GstDecoder *decoder)
+{
+    decoder->sample = gst_app_sink_pull_sample(decoder->appsink);
+    if (!decoder->sample) {
+        SPICE_DEBUG("GStreamer error: could not pull sample");
+        return NULL;
+    }
+
+    GstBuffer *buffer = gst_sample_get_buffer(decoder->sample);
+    if (gst_buffer_map(buffer, &decoder->mapinfo, GST_MAP_READ)) {
+        return decoder->mapinfo.data;
+    }
+    return NULL;
+}
+
+
+/* ---------- VideoDecoder's public API ---------- */
+
+static void gst_decoder_destroy(GstDecoder *decoder)
+{
+    release_last_frame(decoder);
+    reset_pipeline(decoder);
+    g_free(decoder);
+    /* Don't call gst_deinit() as other parts may still be using GStreamer */
+}
+
+static uint8_t* gst_decoder_decode_frame(GstDecoder *decoder,
+                                         SpiceMsgIn *frame_msg)
+{
+    int width, height;
+
+    stream_get_dimensions(decoder->base.stream, frame_msg, &width, &height);
+    if (width != decoder->width || height != decoder->height) {
+        SPICE_DEBUG("video format change: width %d -> %d, height %d -> %d", decoder->width, width, decoder->height, height);
+        decoder->width = width;
+        decoder->height = height;
+        reset_pipeline(decoder);
+    }
+    if (!decoder->pipeline && !construct_pipeline(decoder)) {
+        return NULL;
+    }
+
+    /* Release the output frame buffer early so the pipeline can reuse it.
+     * This also simplifies error handling.
+     */
+    release_last_frame(decoder);
+
+    if (push_compressed_buffer(decoder, frame_msg)) {
+        return pull_raw_frame(decoder);
+    }
+    return NULL;
+}
+
+G_GNUC_INTERNAL
+GstDecoder* create_gstreamer_decoder(int codec_type, display_stream *stream)
+{
+    gst_init(NULL, NULL);
+
+    GstDecoder *decoder = g_malloc0(sizeof(*decoder));
+    decoder->base.destroy = &gst_decoder_destroy;
+    decoder->base.decode_frame = &gst_decoder_decode_frame;
+    decoder->base.codec_type = codec_type;
+    decoder->base.stream = stream;
+
+    return decoder;
+}
diff --git a/src/channel-display-priv.h b/src/channel-display-priv.h
index a01183b..0c9f508 100644
--- a/src/channel-display-priv.h
+++ b/src/channel-display-priv.h
@@ -70,6 +70,7 @@  struct VideoDecoder {
  * @return:     A pointer to a structure implementing the VideoDecoder methods.
  */
 VIDEO_DECODER_T* create_mjpeg_decoder(int codec_type, display_stream *stream);
+VIDEO_DECODER_T* create_gstreamer_decoder(int codec_type, display_stream *stream);
 
 
 typedef struct display_surface {
diff --git a/src/channel-display.c b/src/channel-display.c
index 4033b2f..e9cbf8d 100644
--- a/src/channel-display.c
+++ b/src/channel-display.c
@@ -596,6 +596,10 @@  static void spice_display_channel_reset_capabilities(SpiceChannel *channel)
     if (SPICE_DISPLAY_CHANNEL(channel)->priv->enable_adaptive_streaming) {
         spice_channel_set_capability(SPICE_CHANNEL(channel), SPICE_DISPLAY_CAP_STREAM_REPORT);
     }
+    spice_channel_set_capability(SPICE_CHANNEL(channel), SPICE_DISPLAY_CAP_MULTI_CODEC);
+    spice_channel_set_capability(SPICE_CHANNEL(channel), SPICE_DISPLAY_CAP_CODEC_MJPEG);
+    spice_channel_set_capability(SPICE_CHANNEL(channel), SPICE_DISPLAY_CAP_CODEC_VP8);
+    spice_channel_set_capability(SPICE_CHANNEL(channel), SPICE_DISPLAY_CAP_CODEC_H264);
 }
 
 static void destroy_surface(gpointer data)
@@ -1009,7 +1013,7 @@  static void display_handle_stream_create(SpiceChannel *channel, SpiceMsgIn *in)
         st->video_decoder = create_mjpeg_decoder(op->codec_type, st);
         break;
     default:
-        st->video_decoder = NULL;
+        st->video_decoder = create_gstreamer_decoder(op->codec_type, st);
     }
     if (st->video_decoder == NULL) {
         spice_printerr("could not create a video decoder for codec %d", op->codec_type);

Comments

Hey,

Couple of minor comments below,

On Thu, Aug 27, 2015 at 09:03:06PM +0200, Francois Gouget wrote:
> Based on a patch by Jeremy White.
> 
> Signed-off-by: Francois Gouget <fgouget@codeweavers.com>
> ---
> 
> ***WARNNIG*** This is the first client patch that needs the protocol
>               constants defined in patch 01.
> 
> Changes since take 2:
>  - None.
> 
> 
>  configure.ac               |  47 +++++++---
>  src/Makefile.am            |  12 ++-
>  src/channel-display-gst.c  | 216 +++++++++++++++++++++++++++++++++++++++++++++
>  src/channel-display-priv.h |   1 +
>  src/channel-display.c      |   6 +-
>  5 files changed, 265 insertions(+), 17 deletions(-)
>  create mode 100644 src/channel-display-gst.c
> 
> diff --git a/configure.ac b/configure.ac
> index 0a60ec3..8ee71ca 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -301,7 +301,7 @@ AC_ARG_WITH([audio],
>  
>  case "$with_audio" in
>    gstreamer|pulse|auto*)
> -    PKG_CHECK_MODULES(GST, gstreamer-1.0 gstreamer-base-1.0 gstreamer-app-1.0 gstreamer-audio-1.0, [have_gst=yes], [have_gst=no])
> +    PKG_CHECK_MODULES(GSTAUDIO, gstreamer-1.0 gstreamer-base-1.0 gstreamer-app-1.0 gstreamer-audio-1.0, [have_gst_audio=yes], [have_gst_audio=no])
>      PKG_CHECK_MODULES(PULSE, libpulse libpulse-mainloop-glib, [have_pulse=yes], [have_pulse=no])
>      ;;
>    no*)
> @@ -312,7 +312,7 @@ esac
>  AS_IF([test "x$with_audio" = "xauto" && test "x$have_pulse" = "xyes"],
>        [with_audio=pulse])
>  
> -AS_IF([test "x$with_audio" = "xauto" && test "x$have_gst" = "xyes"],
> +AS_IF([test "x$with_audio" = "xauto" && test "x$have_gst_audio" = "xyes"],
>        [with_audio=gstreamer])
>  
>  AS_IF([test "x$with_audio" = "xauto"],
> @@ -321,22 +321,41 @@ AS_IF([test "x$with_audio" = "xauto"],
>  AS_IF([test "x$with_audio" = "xpulse"],
>        [AS_IF([test "x$have_pulse" = "xyes"],
>               [AC_DEFINE([WITH_PULSE], 1, [Have pulseaudio?])],
> -             [AC_MSG_ERROR([PulseAudio requested but not found])
> -      ])
> -])
> +             [AC_MSG_ERROR([PulseAudio requested but not found])]
> +      )]
> +)
>  AM_CONDITIONAL([WITH_PULSE], [test "x$have_pulse" = "xyes"])
>  AC_SUBST(PULSE_CFLAGS)
>  AC_SUBST(PULSE_LIBS)
>  
>  AS_IF([test "x$with_audio" = "xgstreamer"],
> -      [AS_IF([test "x$have_gst" = "xyes"],
> -             [AC_DEFINE([WITH_GSTAUDIO], 1, [Have GStreamer 1.0?])],
> -             [AC_MSG_ERROR([GStreamer 1.0 requested but not found])
> -      ])
> -])
> -AM_CONDITIONAL([WITH_GSTAUDIO], [test "x$have_gst" = "xyes"])
> -AC_SUBST(GST_CFLAGS)
> -AC_SUBST(GST_LIBS)
> +      [AS_IF([test "x$have_gst_audio" = "xyes"],
> +             [AC_DEFINE([WITH_GSTAUDIO], 1, [Have GStreamer 1.0 audio?])],
> +             [AC_MSG_ERROR([GStreamer 1.0 audio requested but not found])]
> +      )]
> +)
> +AM_CONDITIONAL([WITH_GSTAUDIO], [test "x$have_gst_audio" = "xyes"])
> +AC_SUBST(GSTAUDIO_CFLAGS)
> +AC_SUBST(GSTAUDIO_LIBS)
> +

Fwiw, all these changes could have gone in a separate preliminary commit


> +AC_ARG_ENABLE([gst-video],
> +              AS_HELP_STRING([--enable-gst-video=@<:@auto/yes/no@:>@],
> +                             [Enable GStreamer video support @<:@default=auto@:>@]),
> +              [],
> +              [enable_gst_video="auto"])
> +
> +AS_IF([test "x$enable_gst_video" != "xno"],
> +      [PKG_CHECK_MODULES(GSTVIDEO, gstreamer-1.0 gstreamer-base-1.0 gstreamer-app-1.0 gstreamer-video-1.0, [have_gst_video=yes], [have_gst_video=no])
> +       AS_IF([test "x$have_gst_video" = "xyes"],
> +             [AC_DEFINE([HAVE_GSTVIDEO], 1, [Have GStreamer 1.0 video?])],
> +             [AS_IF([test "x$enable_gst_video" = "xyes"],
> +                    [AC_MSG_ERROR([GStreamer 1.0 video requested but not found])]
> +              )]
> +       )]
> +)
> +AM_CONDITIONAL([HAVE_GSTVIDEO], [test "x$have_gst_video" = "xyes"])]
> +AC_SUBST(GSTVIDEO_CFLAGS)
> +AC_SUBST(GSTVIDEO_LIBS)
>  
>  AC_CHECK_LIB(jpeg, jpeg_destroy_decompress,
>      AC_MSG_CHECKING([for jpeglib.h])
> @@ -702,7 +721,7 @@ SPICE_CFLAGS="$SPICE_CFLAGS $WARN_CFLAGS"
>  
>  AC_SUBST(SPICE_CFLAGS)
>  
> -SPICE_GLIB_CFLAGS="$PIXMAN_CFLAGS $PULSE_CFLAGS $GST_CFLAGS $GLIB2_CFLAGS $GIO_CFLAGS $GOBJECT2_CFLAGS $SSL_CFLAGS $SASL_CFLAGS"
> +SPICE_GLIB_CFLAGS="$PROTOCOL_CFLAGS $PIXMAN_CFLAGS $PULSE_CFLAGS $GSTVIDEO_CFLAGS $GSTAUDIO_CFLAGS $GLIB2_CFLAGS $GIO_CFLAGS $GOBJECT2_CFLAGS $SSL_CFLAGS $SASL_CFLAGS"

PROTOCOL_CFLAGS is already part of COMMON_CFLAGS, any reason why you
needed to add it here too?

>  SPICE_GTK_CFLAGS="$SPICE_GLIB_CFLAGS $GTK_CFLAGS "
>  
>  AC_SUBST(SPICE_GLIB_CFLAGS)
> diff --git a/src/Makefile.am b/src/Makefile.am
> index cf02198..925c75f 100644
> --- a/src/Makefile.am
> +++ b/src/Makefile.am
> @@ -96,7 +96,8 @@ SPICE_COMMON_CPPFLAGS =						\
>  	$(GOBJECT2_CFLAGS)					\
>  	$(SSL_CFLAGS)						\
>  	$(SASL_CFLAGS)						\
> -	$(GST_CFLAGS)						\
> +	$(GSTAUDIO_CFLAGS)					\
> +	$(GSTVIDEO_CFLAGS)					\
>  	$(SMARTCARD_CFLAGS)					\
>  	$(USBREDIR_CFLAGS)					\
>  	$(GUDEV_CFLAGS)						\
> @@ -207,7 +208,8 @@ libspice_client_glib_2_0_la_LIBADD =					\
>  	$(PIXMAN_LIBS)							\
>  	$(SSL_LIBS)							\
>  	$(PULSE_LIBS)							\
> -	$(GST_LIBS)							\
> +	$(GSTAUDIO_LIBS)						\
> +	$(GSTVIDEO_LIBS)						\
>  	$(SASL_LIBS)							\
>  	$(SMARTCARD_LIBS)						\
>  	$(USBREDIR_LIBS)						\
> @@ -340,6 +342,12 @@ libspice_client_glib_2_0_la_SOURCES +=	\
>  	$(NULL)
>  endif
>  
> +if HAVE_GSTVIDEO
> +libspice_client_glib_2_0_la_SOURCES +=	\
> +	channel-display-gst.c		\
> +	$(NULL)
> +endif
> +
>  if WITH_PHODAV
>  libspice_client_glib_2_0_la_SOURCES +=	\
>  	giopipe.c			\
> diff --git a/src/channel-display-gst.c b/src/channel-display-gst.c
> new file mode 100644
> index 0000000..3024356
> --- /dev/null
> +++ b/src/channel-display-gst.c
> @@ -0,0 +1,216 @@
> +/* -*- Mode: C; c-basic-offset: 4; indent-tabs-mode: nil -*- */
> +/*
> +   Copyright (C) 2015 CodeWeavers, Inc
> +
> +   This library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 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
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with this library; if not, see <http://www.gnu.org/licenses/>.
> +*/
> +#include "config.h"
> +
> +#include "spice-client.h"
> +#include "spice-common.h"
> +#include "spice-channel-priv.h"
> +
> +typedef struct GstDecoder GstDecoder;

I'm a bit wary of taking such a generic part of GStreamer namespace,
probably safer to make it SpiceGstDecoder.

> +#define VIDEO_DECODER_T GstDecoder
> +#include "channel-display-priv.h"
> +
> +#include <gst/gst.h>
> +#include <gst/app/gstappsrc.h>
> +#include <gst/app/gstappsink.h>
> +
> +
> +/* GStreamer decoder implementation */
> +
> +struct GstDecoder {
> +    VideoDecoder base;
> +
> +    /* ---------- Video characteristics ---------- */
> +
> +    int width;
> +    int height;
> +
> +    /* ---------- GStreamer pipeline ---------- */
> +
> +    GstElement *pipeline;
> +    GstAppSrc *appsrc;
> +    GstAppSink *appsink;
> +
> +    /* ---------- Output frame data ---------- */
> +
> +    GstSample *sample;
> +    GstMapInfo mapinfo;
> +};
> +
> +
> +/* ---------- GStreamer pipeline ---------- */
> +
> +static void reset_pipeline(GstDecoder *decoder)
> +{
> +    if (!decoder->pipeline) {
> +        return;
> +    }
> +
> +    gst_element_set_state(decoder->pipeline, GST_STATE_NULL);
> +    gst_object_unref(decoder->appsrc);
> +    gst_object_unref(decoder->appsink);
> +    gst_object_unref(decoder->pipeline);
> +    decoder->pipeline = NULL;
> +}
> +
> +static gboolean construct_pipeline(GstDecoder *decoder)
> +{
> +    const gchar *src_caps, *gstdec_name;
> +    switch (decoder->base.codec_type) {
> +    case SPICE_VIDEO_CODEC_TYPE_MJPEG:
> +        src_caps = "image/jpeg";
> +        gstdec_name = "jpegdec";
> +        break;
> +    case SPICE_VIDEO_CODEC_TYPE_VP8:
> +        src_caps = "video/x-vp8";
> +        gstdec_name = "vp8dec";
> +        break;
> +    case SPICE_VIDEO_CODEC_TYPE_H264:
> +        src_caps = "video/x-h264";
> +        gstdec_name = "h264parse ! avdec_h264";
> +        break;
> +    default:
> +        spice_warning("Unknown codec type %d", decoder->base.codec_type);
> +        return -1;
> +    }
> +
> +    GError *err = NULL;
> +    gchar *desc = g_strdup_printf("appsrc name=src format=2 do-timestamp=1 caps=%s ! %s ! videoconvert ! appsink name=sink caps=video/x-raw,format=BGRx", src_caps, gstdec_name);
> +    SPICE_DEBUG("GStreamer pipeline: %s", desc);
> +    decoder->pipeline = gst_parse_launch_full(desc, NULL, GST_PARSE_FLAG_FATAL_ERRORS, &err);
> +    g_free(desc);
> +    if (!decoder->pipeline) {
> +        spice_warning("GStreamer error: %s", err->message);
> +        g_clear_error(&err);
> +        return FALSE;
> +    }
> +
> +    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"));
> +
> +    if (gst_element_set_state(decoder->pipeline, GST_STATE_PLAYING) == GST_STATE_CHANGE_FAILURE) {
> +        SPICE_DEBUG("GStreamer error: Unable to set the pipeline to the playing state.");
> +        reset_pipeline(decoder);
> +        return FALSE;
> +    }
> +
> +    return TRUE;
> +}
> +
> +static gboolean push_compressed_buffer(GstDecoder *decoder,
> +                                       SpiceMsgIn *frame_msg)
> +{
> +    uint8_t *data;
> +    uint32_t size = spice_msg_in_frame_data(frame_msg, &data);
> +    if (size == 0) {
> +        SPICE_DEBUG("got an empty frame buffer!");
> +        return FALSE;
> +    }
> +
> +    // TODO.  Grr.  Seems like a wasted alloc
> +    gpointer d = g_malloc(size);
> +    memcpy(d, data, size);
> +    GstBuffer *buffer = gst_buffer_new_wrapped(d, size);

I think you could hide it with gst_buffer_new() + gst_buffer_fill(), but
the memory would still end up being copied.

> +
> +    if (gst_app_src_push_buffer(decoder->appsrc, buffer) != GST_FLOW_OK) {
> +        SPICE_DEBUG("GStreamer error: unable to push frame of size %d", size);
> +        return FALSE;
> +    }
> +
> +    return TRUE;
> +}
> +
> +static void release_last_frame(GstDecoder *decoder)
> +{
> +    if (decoder->mapinfo.memory) {
> +        gst_memory_unmap(decoder->mapinfo.memory, &decoder->mapinfo);
> +        gst_memory_unref(decoder->mapinfo.memory);

This is opencoding gst_buffer_unmap(), which is gst_buffer_map()
documentation says should be used to release the resources which were
mapped.

> +        decoder->mapinfo.memory = NULL;
> +    }
> +    if (decoder->sample) {
> +        gst_sample_unref(decoder->sample);
> +        decoder->sample = NULL;
> +    }
> +}
> +
> +static uint8_t* pull_raw_frame(GstDecoder *decoder)
> +{
> +    decoder->sample = gst_app_sink_pull_sample(decoder->appsink);
> +    if (!decoder->sample) {
> +        SPICE_DEBUG("GStreamer error: could not pull sample");
> +        return NULL;
> +    }
> +
> +    GstBuffer *buffer = gst_sample_get_buffer(decoder->sample);

I'd take a ref on the returned buffer, and unref decoder->sample right
away (ie no need to have it as GstDecoder::sample)

> +    if (gst_buffer_map(buffer, &decoder->mapinfo, GST_MAP_READ)) {
> +        return decoder->mapinfo.data;
> +    }
> +    return NULL;
> +}
> +
> +
> +/* ---------- VideoDecoder's public API ---------- */
> +
> +static void gst_decoder_destroy(GstDecoder *decoder)
> +{
> +    release_last_frame(decoder);
> +    reset_pipeline(decoder);
> +    g_free(decoder);
> +    /* Don't call gst_deinit() as other parts may still be using GStreamer */
> +}
> +
> +static uint8_t* gst_decoder_decode_frame(GstDecoder *decoder,
> +                                         SpiceMsgIn *frame_msg)
> +{
> +    int width, height;
> +
> +    stream_get_dimensions(decoder->base.stream, frame_msg, &width, &height);
> +    if (width != decoder->width || height != decoder->height) {
> +        SPICE_DEBUG("video format change: width %d -> %d, height %d -> %d", decoder->width, width, decoder->height, height);
> +        decoder->width = width;
> +        decoder->height = height;
> +        reset_pipeline(decoder);
> +    }
> +    if (!decoder->pipeline && !construct_pipeline(decoder)) {
> +        return NULL;
> +    }
> +
> +    /* Release the output frame buffer early so the pipeline can reuse it.
> +     * This also simplifies error handling.
> +     */
> +    release_last_frame(decoder);
> +
> +    if (push_compressed_buffer(decoder, frame_msg)) {
> +        return pull_raw_frame(decoder);
> +    }
> +    return NULL;
> +}
> +
> +G_GNUC_INTERNAL
> +GstDecoder* create_gstreamer_decoder(int codec_type, display_stream *stream)
> +{
> +    gst_init(NULL, NULL);

I'd do it much earlier in spice-gtk startup so that it's only done once.
Also, I suspect this can be slow, so better not to do it while a spice
session is going on if possible. GOnce could be used to force it to be
done only once. gst_init_check() would be more appropriate as gst_init()
can abort().

> +
> +    GstDecoder *decoder = g_malloc0(sizeof(*decoder));

g_new0(GstDecoder, 1); maybe

> +    decoder->base.destroy = &gst_decoder_destroy;
> +    decoder->base.decode_frame = &gst_decoder_decode_frame;
> +    decoder->base.codec_type = codec_type;
> +    decoder->base.stream = stream;
> +
> +    return decoder;
> +}
> diff --git a/src/channel-display-priv.h b/src/channel-display-priv.h
> index a01183b..0c9f508 100644
> --- a/src/channel-display-priv.h
> +++ b/src/channel-display-priv.h
> @@ -70,6 +70,7 @@ struct VideoDecoder {
>   * @return:     A pointer to a structure implementing the VideoDecoder methods.
>   */
>  VIDEO_DECODER_T* create_mjpeg_decoder(int codec_type, display_stream *stream);
> +VIDEO_DECODER_T* create_gstreamer_decoder(int codec_type, display_stream *stream);

missing #ifdef HAVE_GSTVIDEO

>  
>  
>  typedef struct display_surface {
> diff --git a/src/channel-display.c b/src/channel-display.c
> index 4033b2f..e9cbf8d 100644
> --- a/src/channel-display.c
> +++ b/src/channel-display.c
> @@ -596,6 +596,10 @@ static void spice_display_channel_reset_capabilities(SpiceChannel *channel)
>      if (SPICE_DISPLAY_CHANNEL(channel)->priv->enable_adaptive_streaming) {
>          spice_channel_set_capability(SPICE_CHANNEL(channel), SPICE_DISPLAY_CAP_STREAM_REPORT);
>      }
> +    spice_channel_set_capability(SPICE_CHANNEL(channel), SPICE_DISPLAY_CAP_MULTI_CODEC);
> +    spice_channel_set_capability(SPICE_CHANNEL(channel), SPICE_DISPLAY_CAP_CODEC_MJPEG);
> +    spice_channel_set_capability(SPICE_CHANNEL(channel), SPICE_DISPLAY_CAP_CODEC_VP8);
> +    spice_channel_set_capability(SPICE_CHANNEL(channel), SPICE_DISPLAY_CAP_CODEC_H264);

here too I think

>  }
>  
>  static void destroy_surface(gpointer data)
> @@ -1009,7 +1013,7 @@ static void display_handle_stream_create(SpiceChannel *channel, SpiceMsgIn *in)
>          st->video_decoder = create_mjpeg_decoder(op->codec_type, st);
>          break;
>      default:
> -        st->video_decoder = NULL;
> +        st->video_decoder = create_gstreamer_decoder(op->codec_type, st);


Can it be the default decoder before the last patch in the series? Or
should it be

case SPICE_VIDEO_CODEC_TYPE_VP8:
case SPICE_VIDEO_CODEC_TYPE_H264:
    st->video_decoder = create_gstreamer_decoder(op->codec_type, st);

default:
    st->video_decoder = NULL;
?

This needs to be wrapped in #ifdef HAVE_GSTVIDEO

Christophe