[Spice-devel,v7,05/23] server: Let the administrator pick the video encoder and codec

Submitted by Francois Gouget on Dec. 16, 2015, 3:17 p.m.

Details

Message ID alpine.DEB.2.20.1512161121350.16981@amboise
State New
Headers show
Series "Add GStreamer support for video streaming" ( rev: 1 ) in Spice

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Commit Message

Francois Gouget Dec. 16, 2015, 3:17 p.m.
The Spice server administrator can specify the preferred encoder and
codec preferences to optimize for CPU or bandwidth usage. Preferences
are described in a semi-colon separated list of encoder:codec pairs.
The server has a default preference list which can explicitly be
selected by specifying 'auto'.

The server then picks a codec supported by the client based on the
following new client capabilities:
 * SPICE_DISPLAY_CAP_MULTI_CODEC which denotes a recent client that
   supports multiple codecs. This capability is needed to not have to
   hardcode that MJPEG is supported. This makes it possible to write
   clients that don't support MJPEG.
 * SPICE_DISPLAY_CAP_CODEC_XXX, where XXX is a supported codec. Note
   that for now the server only supports the MJPEG codec.

Signed-off-by: Francois Gouget <fgouget@codeweavers.com>
---
 server/dcc-send.c          |   2 +-
 server/display-channel.c   |  13 ++++
 server/display-channel.h   |   5 ++
 server/gstreamer-encoder.c |   6 +-
 server/mjpeg-encoder.c     |   6 +-
 server/red-dispatcher.c    |  17 +++++
 server/red-dispatcher.h    |   8 +++
 server/red-worker.c        |  14 ++++
 server/reds.c              | 155 ++++++++++++++++++++++++++++++++++++++++-----
 server/reds.h              |  13 ++++
 server/spice-server.h      |   1 +
 server/spice-server.syms   |   5 ++
 server/stream.c            |  29 +++++++--
 server/video-encoder.h     |  23 ++++++-
 14 files changed, 269 insertions(+), 28 deletions(-)

Patch hide | download patch | download mbox

diff --git a/server/dcc-send.c b/server/dcc-send.c
index fd11b09..e13f04f 100644
--- a/server/dcc-send.c
+++ b/server/dcc-send.c
@@ -2189,7 +2189,7 @@  static void marshall_stream_start(RedChannelClient *rcc,
     stream_create.surface_id = 0;
     stream_create.id = get_stream_id(DCC_TO_DC(dcc), stream);
     stream_create.flags = stream->top_down ? SPICE_STREAM_FLAGS_TOP_DOWN : 0;
-    stream_create.codec_type = SPICE_VIDEO_CODEC_TYPE_MJPEG;
+    stream_create.codec_type = agent->video_encoder->codec_type;
 
     stream_create.src_width = stream->width;
     stream_create.src_height = stream->height;
diff --git a/server/display-channel.c b/server/display-channel.c
index ec4ca10..76d2a41 100644
--- a/server/display-channel.c
+++ b/server/display-channel.c
@@ -219,6 +219,17 @@  void display_channel_set_stream_video(DisplayChannel *display, int stream_video)
     display->stream_video = stream_video;
 }
 
+void display_channel_set_video_codecs(DisplayChannel *display,
+                                      int num_video_codecs,
+                                      RedVideoCodec *video_codecs)
+{
+    spice_return_if_fail(display);
+    spice_return_if_fail(num_video_codecs > RED_MAX_VIDEO_CODECS);
+
+    display->num_video_codecs = num_video_codecs;
+    memcpy(display->video_codecs, video_codecs, sizeof(display->video_codecs));
+}
+
 static void stop_streams(DisplayChannel *display)
 {
     Ring *ring = &display->streams;
@@ -2072,6 +2083,8 @@  DisplayChannel* display_channel_new(RedWorker *worker, int migrate, int stream_v
     drawables_init(display);
     image_cache_init(&display->image_cache);
     display->stream_video = stream_video;
+    display->num_video_codecs = num_video_codecs;
+    memcpy(display->video_codecs, video_codecs, sizeof(display->video_codecs));
     display_channel_init_streams(display);
 
     return display;
diff --git a/server/display-channel.h b/server/display-channel.h
index bf29cd3..f55d23b 100644
--- a/server/display-channel.h
+++ b/server/display-channel.h
@@ -185,6 +185,8 @@  struct DisplayChannel {
     uint32_t glz_drawable_count;
 
     int stream_video;
+    uint32_t num_video_codecs;
+    RedVideoCodec video_codecs[RED_MAX_VIDEO_CODECS];
     uint32_t stream_count;
     Stream streams_buf[NUM_STREAMS];
     Stream *free_streams;
@@ -273,6 +275,9 @@  void                       display_channel_update                    (DisplayCha
 void                       display_channel_free_some                 (DisplayChannel *display);
 void                       display_channel_set_stream_video          (DisplayChannel *display,
                                                                       int stream_video);
+void                       display_channel_set_video_codecs          (DisplayChannel *display,
+                                                                      int num_video_codecs,
+                                                                      RedVideoCodec *video_codecs);
 int                        display_channel_get_streams_timeout       (DisplayChannel *display);
 void                       display_channel_compress_stats_print      (const DisplayChannel *display);
 void                       display_channel_compress_stats_reset      (DisplayChannel *display);
diff --git a/server/gstreamer-encoder.c b/server/gstreamer-encoder.c
index e934180..edf87df 100644
--- a/server/gstreamer-encoder.c
+++ b/server/gstreamer-encoder.c
@@ -494,10 +494,13 @@  static void spice_gst_encoder_get_stats(VideoEncoder *video_encoder,
     }
 }
 
-VideoEncoder *gstreamer_encoder_new(uint64_t starting_bit_rate,
+VideoEncoder *gstreamer_encoder_new(SpiceVideoCodecType codec_type,
+                                    uint64_t starting_bit_rate,
                                     VideoEncoderRateControlCbs *cbs,
                                     void *cbs_opaque)
 {
+    spice_return_val_if_fail(codec_type == SPICE_VIDEO_CODEC_TYPE_MJPEG, NULL);
+
     GError *err = NULL;
     if (!gst_init_check(NULL, NULL, &err)) {
         spice_warning("GStreamer error: %s", err->message);
@@ -512,6 +515,7 @@  VideoEncoder *gstreamer_encoder_new(uint64_t starting_bit_rate,
     encoder->base.notify_server_frame_drop = &spice_gst_encoder_notify_server_frame_drop;
     encoder->base.get_bit_rate = &spice_gst_encoder_get_bit_rate;
     encoder->base.get_stats = &spice_gst_encoder_get_stats;
+    encoder->base.codec_type = codec_type;
 
     if (cbs) {
         encoder->cbs = *cbs;
diff --git a/server/mjpeg-encoder.c b/server/mjpeg-encoder.c
index eb1a333..607bea8 100644
--- a/server/mjpeg-encoder.c
+++ b/server/mjpeg-encoder.c
@@ -1344,18 +1344,22 @@  static void mjpeg_encoder_get_stats(VideoEncoder *video_encoder,
     stats->avg_quality = (double)encoder->avg_quality / encoder->num_frames;
 }
 
-VideoEncoder *mjpeg_encoder_new(uint64_t starting_bit_rate,
+VideoEncoder *mjpeg_encoder_new(SpiceVideoCodecType codec_type,
+                                uint64_t starting_bit_rate,
                                 VideoEncoderRateControlCbs *cbs,
                                 void *cbs_opaque)
 {
     MJpegEncoder *encoder = spice_new0(MJpegEncoder, 1);
 
+    spice_return_val_if_fail(codec_type == SPICE_VIDEO_CODEC_TYPE_MJPEG, NULL);
+
     encoder->base.destroy = &mjpeg_encoder_destroy;
     encoder->base.encode_frame = &mjpeg_encoder_encode_frame;
     encoder->base.client_stream_report = &mjpeg_encoder_client_stream_report;
     encoder->base.notify_server_frame_drop = &mjpeg_encoder_notify_server_frame_drop;
     encoder->base.get_bit_rate = &mjpeg_encoder_get_bit_rate;
     encoder->base.get_stats = &mjpeg_encoder_get_stats;
+    encoder->base.codec_type = codec_type;
     encoder->first_frame = TRUE;
     encoder->rate_control.byte_rate = starting_bit_rate / 8;
     encoder->starting_bit_rate = starting_bit_rate;
diff --git a/server/red-dispatcher.c b/server/red-dispatcher.c
index 0810798..c81039b 100644
--- a/server/red-dispatcher.c
+++ b/server/red-dispatcher.c
@@ -26,6 +26,7 @@ 
 #include <pthread.h>
 #include <sys/socket.h>
 #include <inttypes.h>
+#include <ctype.h>
 
 #include <spice/qxl_dev.h>
 #include "common/quic.h"
@@ -744,6 +745,22 @@  void red_dispatcher_on_sv_change(void)
     }
 }
 
+void red_dispatcher_on_vc_change(void)
+{
+    RedWorkerMessageSetVideoCodecs payload;
+    int compression_level = calc_compression_level();
+    RedDispatcher *now = dispatchers;
+    while (now) {
+        now->qxl->st->qif->set_compression_level(now->qxl, compression_level);
+        payload.num_video_codecs = num_video_codecs;
+        payload.video_codecs = video_codecs;
+        dispatcher_send_message(&now->dispatcher,
+                                RED_WORKER_MESSAGE_SET_VIDEO_CODECS,
+                                &payload);
+        now = now->next;
+    }
+}
+
 void red_dispatcher_set_mouse_mode(uint32_t mode)
 {
     RedWorkerMessageSetMouseMode payload;
diff --git a/server/red-dispatcher.h b/server/red-dispatcher.h
index d99695d..b46668e 100644
--- a/server/red-dispatcher.h
+++ b/server/red-dispatcher.h
@@ -19,6 +19,7 @@ 
 #define _H_RED_DISPATCHER
 
 #include "red-channel.h"
+#include "video-encoder.h"
 
 typedef struct RedDispatcher RedDispatcher;
 
@@ -28,6 +29,7 @@  void red_dispatcher_init(QXLInstance *qxl);
 
 void red_dispatcher_on_ic_change(void);
 void red_dispatcher_on_sv_change(void);
+void red_dispatcher_on_vc_change(void);
 void red_dispatcher_set_mouse_mode(uint32_t mode);
 void red_dispatcher_on_vm_stop(void);
 void red_dispatcher_on_vm_start(void);
@@ -88,6 +90,7 @@  enum {
 
     RED_WORKER_MESSAGE_MONITORS_CONFIG_ASYNC,
     RED_WORKER_MESSAGE_DRIVER_UNLOAD,
+    RED_WORKER_MESSAGE_SET_VIDEO_CODECS,
 
     RED_WORKER_MESSAGE_COUNT // LAST
 };
@@ -225,6 +228,11 @@  typedef struct RedWorkerMessageSetStreamingVideo {
     uint32_t streaming_video;
 } RedWorkerMessageSetStreamingVideo;
 
+typedef struct RedWorkerMessageSetVideoCodecs {
+    uint32_t num_video_codecs;
+    RedVideoCodec* video_codecs;
+} RedWorkerMessageSetVideoCodecs;
+
 typedef struct RedWorkerMessageSetMouseMode {
     uint32_t mode;
 } RedWorkerMessageSetMouseMode;
diff --git a/server/red-worker.c b/server/red-worker.c
index dfaf4ba..416cb44 100644
--- a/server/red-worker.c
+++ b/server/red-worker.c
@@ -1237,6 +1237,15 @@  static void handle_dev_set_streaming_video(void *opaque, void *payload)
     display_channel_set_stream_video(worker->display_channel, msg->streaming_video);
 }
 
+void handle_dev_set_video_codecs(void *opaque, void *payload)
+{
+    RedWorkerMessageSetVideoCodecs *msg = payload;
+    RedWorker *worker = opaque;
+
+    display_channel_set_video_codecs(worker->display_channel,
+                                     msg->num_video_codecs, msg->video_codecs);
+}
+
 static void handle_dev_set_mouse_mode(void *opaque, void *payload)
 {
     RedWorkerMessageSetMouseMode *msg = payload;
@@ -1494,6 +1503,11 @@  static void register_callbacks(Dispatcher *dispatcher)
                                 sizeof(RedWorkerMessageSetStreamingVideo),
                                 DISPATCHER_NONE);
     dispatcher_register_handler(dispatcher,
+                                RED_WORKER_MESSAGE_SET_VIDEO_CODECS,
+                                handle_dev_set_video_codecs,
+                                sizeof(RedWorkerMessageSetVideoCodecs),
+                                DISPATCHER_NONE);
+    dispatcher_register_handler(dispatcher,
                                 RED_WORKER_MESSAGE_SET_MOUSE_MODE,
                                 handle_dev_set_mouse_mode,
                                 sizeof(RedWorkerMessageSetMouseMode),
diff --git a/server/reds.c b/server/reds.c
index e8cf168..b4bb4d1 100644
--- a/server/reds.c
+++ b/server/reds.c
@@ -3364,12 +3364,27 @@  SPICE_GNUC_VISIBLE SpiceServer *spice_server_new(void)
     return reds;
 }
 
-typedef struct RendererInfo {
-    int id;
+typedef struct {
+    uint32_t id;
     const char *name;
-} RendererInfo;
+} EnumNames;
 
-static RendererInfo renderers_info[] = {
+static int name_to_enum(const EnumNames names[], const char *string, uint32_t *id)
+{
+    if (string) {
+        int i = 0;
+        while (names[i].name) {
+            if (strcmp(string, names[i].name) == 0) {
+                *id = names[i].id;
+                return TRUE;
+            }
+            i++;
+        }
+    }
+    return FALSE;
+}
+
+static EnumNames renderer_names[] = {
     {RED_RENDERER_SW, "sw"},
     {RED_RENDERER_INVALID, NULL},
 };
@@ -3377,26 +3392,120 @@  static RendererInfo renderers_info[] = {
 uint32_t renderers[RED_RENDERER_LAST];
 uint32_t num_renderers = 0;
 
-static RendererInfo *find_renderer(const char *name)
+static int red_add_renderer(const char *name)
 {
-    RendererInfo *inf = renderers_info;
-    while (inf->name) {
-        if (strcmp(name, inf->name) == 0) {
-            return inf;
-        }
-        inf++;
+    uint32_t renderer;
+
+    if (num_renderers == RED_RENDERER_LAST ||
+        !name_to_enum(renderer_names, name, &renderer)) {
+        return FALSE;
     }
-    return NULL;
+    renderers[num_renderers++] = renderer;
+    return TRUE;
 }
 
-static int red_add_renderer(const char *name)
+static const EnumNames video_encoder_names[] = {
+    {0, "spice"},
+    {1, "gstreamer"},
+    {0, NULL},
+};
+
+static new_video_encoder_t video_encoder_procs[] = {
+    &mjpeg_encoder_new,
+#ifdef HAVE_GSTREAMER_1_0
+    &gstreamer_encoder_new,
+#else
+    NULL,
+#endif
+};
+
+static const EnumNames video_codec_names[] = {
+    {SPICE_VIDEO_CODEC_TYPE_MJPEG, "mjpeg"},
+    {SPICE_VIDEO_CODEC_TYPE_VP8, "vp8"},
+    {0, NULL},
+};
+
+static const EnumNames video_cap_names[] = {
+    {SPICE_DISPLAY_CAP_CODEC_MJPEG, "mjpeg"},
+    {SPICE_DISPLAY_CAP_CODEC_VP8, "vp8"},
+    {0, NULL},
+};
+
+
+RedVideoCodec video_codecs[RED_MAX_VIDEO_CODECS];
+uint32_t num_video_codecs = 0;
+
+/* Expected string:  encoder:codec;encoder:codec */
+static const char* parse_video_codecs(const char *codecs, char **encoder,
+                                      char **codec)
 {
-    RendererInfo *inf;
+    while (*codecs == ';') {
+        codecs++;
+    }
+    if (!*codecs) {
+        return NULL;
+    }
+    int n;
+    *encoder = *codec = NULL;
+    if (sscanf(codecs, "%m[0-9a-zA-Z_]:%m[0-9a-zA-Z_]%n", encoder, codec, &n) != 2) {
+        spice_warning("spice: invalid encoder:codec value at %s", codecs);
+        return strchr(codecs, ';');
+    }
+    return codecs + n;
+}
 
-    if (num_renderers == RED_RENDERER_LAST || !(inf = find_renderer(name))) {
-        return FALSE;
+static int red_set_video_codecs(const char *codecs)
+{
+    uint32_t encoder;
+    SpiceVideoCodecType type;
+    uint32_t cap;
+    char *encoder_name, *codec_name;
+    static RedVideoCodec new_codecs[RED_MAX_VIDEO_CODECS];
+    int count;
+    const char* c;
+
+    if (strcmp(codecs, "auto") == 0) {
+        codecs = VIDEO_ENCODER_DEFAULT_PREFERENCE;
+    }
+
+    c = codecs;
+    count = 0;
+    while ( (c = parse_video_codecs(c, &encoder_name, &codec_name)) ) {
+        int skip = FALSE;
+        if (!encoder_name || !codec_name) {
+            skip = TRUE;
+
+        } else if (!name_to_enum(video_encoder_names, encoder_name, &encoder)) {
+            spice_warning("spice: unknown video encoder %s", encoder_name);
+            skip = TRUE;
+
+        } else if (!name_to_enum(video_codec_names, codec_name, &type) ||
+                   !name_to_enum(video_cap_names, codec_name, &cap)) {
+            spice_warning("spice: unknown video codec %s", codec_name);
+            skip = TRUE;
+
+        } else if (!video_encoder_procs[encoder]) {
+            spice_warning("spice: unsupported video encoder %s", encoder_name);
+            skip = TRUE;
+        }
+
+        free(encoder_name);
+        free(codec_name);
+        if (skip) {
+            continue;
+        }
+
+        if (count == RED_MAX_VIDEO_CODECS) {
+            spice_warning("spice: cannot add more than %d video codec preferences", count);
+            break;
+        }
+        new_codecs[count].create = video_encoder_procs[encoder];
+        new_codecs[count].type = type;
+        new_codecs[count].cap = cap;
+        count++;
     }
-    renderers[num_renderers++] = inf->id;
+    num_video_codecs = count;
+    memcpy(video_codecs, new_codecs, sizeof(video_codecs));
     return TRUE;
 }
 
@@ -3725,6 +3834,18 @@  SPICE_GNUC_VISIBLE int spice_server_set_streaming_video(SpiceServer *s, int valu
     return 0;
 }
 
+SPICE_GNUC_VISIBLE int spice_server_set_video_codecs(SpiceServer *s, const char* video_codecs)
+{
+    spice_assert(reds == s);
+
+    if (!red_set_video_codecs(video_codecs)) {
+        return -1;
+    }
+
+    red_dispatcher_on_vc_change();
+    return 0;
+}
+
 SPICE_GNUC_VISIBLE int spice_server_set_playback_compression(SpiceServer *s, int enable)
 {
     spice_assert(reds == s);
diff --git a/server/reds.h b/server/reds.h
index 4d1b631..afad933 100644
--- a/server/reds.h
+++ b/server/reds.h
@@ -29,6 +29,7 @@ 
 #include "spice.h"
 #include "red-channel.h"
 #include "migration-protocol.h"
+#include "video-encoder.h"
 
 struct QXLState {
     QXLInterface          *qif;
@@ -70,7 +71,19 @@  extern uint32_t renderers[RED_RENDERER_LAST];
 extern uint32_t num_renderers;
 
 extern struct SpiceCoreInterface *core;
+
+#define RED_MAX_VIDEO_CODECS 8
+
+enum {
+    SPICE_STREAMING_INVALID,
+    SPICE_STREAMING_SPICE,
+    SPICE_STREAMING_GSTREAMER
+};
+
 extern uint32_t streaming_video;
+uint32_t num_video_codecs;
+RedVideoCodec video_codecs[RED_MAX_VIDEO_CODECS];
+
 extern SpiceImageCompression image_compression;
 extern spice_wan_compression_t jpeg_state;
 extern spice_wan_compression_t zlib_glz_state;
diff --git a/server/spice-server.h b/server/spice-server.h
index c2ff61d..198dcf0 100644
--- a/server/spice-server.h
+++ b/server/spice-server.h
@@ -107,6 +107,7 @@  enum {
 };
 
 int spice_server_set_streaming_video(SpiceServer *s, int value);
+int spice_server_set_video_codecs(SpiceServer *s, const char* video_codecs);
 int spice_server_set_playback_compression(SpiceServer *s, int enable);
 int spice_server_set_agent_mouse(SpiceServer *s, int enable);
 int spice_server_set_agent_copypaste(SpiceServer *s, int enable);
diff --git a/server/spice-server.syms b/server/spice-server.syms
index d65e14d..b8f06a2 100644
--- a/server/spice-server.syms
+++ b/server/spice-server.syms
@@ -162,3 +162,8 @@  global:
     spice_replay_next_cmd;
     spice_replay_free_cmd;
 } SPICE_SERVER_0.12.5;
+
+SPICE_SERVER_0.12.7 {
+global:
+    spice_server_set_video_codecs;
+} SPICE_SERVER_0.12.6;
diff --git a/server/stream.c b/server/stream.c
index bbc7003..0db9c58 100644
--- a/server/stream.c
+++ b/server/stream.c
@@ -705,17 +705,34 @@  static VideoEncoder* dcc_create_video_encoder(DisplayChannelClient *dcc,
                                               VideoEncoderRateControlCbs *cbs,
                                               void *cbs_opaque)
 {
+    DisplayChannel *display = DCC_TO_DC(dcc);
     RedChannelClient *rcc = RED_CHANNEL_CLIENT(dcc);
     int client_has_multi_codec = red_channel_client_test_remote_cap(rcc, SPICE_DISPLAY_CAP_MULTI_CODEC);
-    if (!client_has_multi_codec || red_channel_client_test_remote_cap(rcc, SPICE_DISPLAY_CAP_CODEC_MJPEG)) {
-#ifdef HAVE_GSTREAMER_1_0
-        VideoEncoder* video_encoder = gstreamer_encoder_new(starting_bit_rate, cbs, cbs_opaque);
+    int i;
+
+    for (i = 0; i < display->num_video_codecs; i++) {
+        RedVideoCodec* video_codec = display->video_codecs+i;
+
+        if (!client_has_multi_codec &&
+            video_codec->type != SPICE_VIDEO_CODEC_TYPE_MJPEG) {
+            /* Old clients only support MJPEG */
+            continue;
+        }
+        if (client_has_multi_codec &&
+            !red_channel_client_test_remote_cap(rcc, video_codec->cap)) {
+            /* The client is recent but does not support this codec */
+            continue;
+        }
+
+        VideoEncoder* video_encoder = video_codec->create(video_codec->type, starting_bit_rate, cbs, cbs_opaque);
         if (video_encoder) {
             return video_encoder;
         }
-#endif
-        /* Use the builtin MJPEG video encoder as a fallback */
-        return mjpeg_encoder_new(starting_bit_rate, cbs, cbs_opaque);
+    }
+
+    /* Try to use the builtin MJPEG video encoder as a fallback */
+    if (!client_has_multi_codec || red_channel_client_test_remote_cap(rcc, SPICE_DISPLAY_CAP_CODEC_MJPEG)) {
+        return mjpeg_encoder_new(SPICE_VIDEO_CODEC_TYPE_MJPEG, starting_bit_rate, cbs, cbs_opaque);
     }
 
     return NULL;
diff --git a/server/video-encoder.h b/server/video-encoder.h
index 1c6ceb3..b8a21e1 100644
--- a/server/video-encoder.h
+++ b/server/video-encoder.h
@@ -117,6 +117,9 @@  struct VideoEncoder {
      *              statistics.
      */
     void (*get_stats)(VideoEncoder *encoder, VideoEncoderStats *stats);
+
+    /* The codec being used by the video encoder */
+    SpiceVideoCodecType codec_type;
 };
 
 
@@ -146,6 +149,7 @@  typedef struct VideoEncoderRateControlCbs {
 
 /* Instantiates the video encoder.
  *
+ * @codec_type:        The codec to use.
  * @starting_bit_rate: An initial estimate of the available stream bit rate or
  *                     zero if the client does not support rate control.
  * @cbs:               A set of callback methods to be used for rate control.
@@ -153,13 +157,28 @@  typedef struct VideoEncoderRateControlCbs {
  * @return:            A pointer to a structure implementing the VideoEncoder
  *                     methods.
  */
-VideoEncoder* mjpeg_encoder_new(uint64_t starting_bit_rate,
+typedef VideoEncoder* (*new_video_encoder_t)(SpiceVideoCodecType codec_type,
+                                             uint64_t starting_bit_rate,
+                                             VideoEncoderRateControlCbs *cbs,
+                                             void *cbs_opaque);
+
+typedef struct RedVideoCodec {
+    new_video_encoder_t create;
+    SpiceVideoCodecType type;
+    uint32_t cap;
+} RedVideoCodec;
+
+VideoEncoder* mjpeg_encoder_new(SpiceVideoCodecType codec_type,
+                                uint64_t starting_bit_rate,
                                 VideoEncoderRateControlCbs *cbs,
                                 void *cbs_opaque);
 #ifdef HAVE_GSTREAMER_1_0
-VideoEncoder* gstreamer_encoder_new(uint64_t starting_bit_rate,
+VideoEncoder* gstreamer_encoder_new(SpiceVideoCodecType codec_type,
+                                    uint64_t starting_bit_rate,
                                     VideoEncoderRateControlCbs *cbs,
                                     void *cbs_opaque);
 #endif
 
+#define VIDEO_ENCODER_DEFAULT_PREFERENCE "spice:mjpeg;gstreamer:mjpeg"
+
 #endif