gstreamer/ext/gl/gstglstereomix.c

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/*
* Combine video streams to 3D stereo
*
* GStreamer
* Copyright (C) 2009 Julien Isorce <julien.isorce@gmail.com>
* Copyright (C) 2014 Jan Schmidt <jan@noraisin.net>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "gstglstereomix.h"
#define GST_CAT_DEFAULT gst_gl_stereo_mix_debug
GST_DEBUG_CATEGORY (gst_gl_stereo_mix_debug);
G_DEFINE_TYPE (GstGLStereoMixPad, gst_gl_stereo_mix_pad, GST_TYPE_GL_MIXER_PAD);
static void
gst_gl_stereo_mix_pad_class_init (GstGLStereoMixPadClass * klass)
{
}
static void
gst_gl_stereo_mix_pad_init (GstGLStereoMixPad * pad)
{
}
#define gst_gl_stereo_mix_parent_class parent_class
G_DEFINE_TYPE (GstGLStereoMix, gst_gl_stereo_mix, GST_TYPE_GL_MIXER);
static GstCaps *_update_caps (GstVideoAggregator * vagg, GstCaps * caps,
GstCaps * filter);
static gboolean _negotiated_caps (GstVideoAggregator * videoaggregator,
GstCaps * caps);
gboolean gst_gl_stereo_mix_make_output (GstGLStereoMix * mix);
static gboolean gst_gl_stereo_mix_process_frames (GstGLStereoMix * mixer);
#define DEFAULT_DOWNMIX GST_GL_STEREO_DOWNMIX_ANAGLYPH_GREEN_MAGENTA_DUBOIS
/* GLStereoMix signals and args */
enum
{
/* FILL ME */
LAST_SIGNAL
};
enum
{
PROP_0,
PROP_DOWNMIX_MODE
};
static GstStaticPadTemplate src_factory = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("video/x-raw(" GST_CAPS_FEATURE_MEMORY_GL_MEMORY "), "
"format = (string) RGBA, "
"width = " GST_VIDEO_SIZE_RANGE ", "
"height = " GST_VIDEO_SIZE_RANGE ", "
"framerate = " GST_VIDEO_FPS_RANGE ","
"texture-target = (string) 2D"
"; "
GST_VIDEO_CAPS_MAKE_WITH_FEATURES
(GST_CAPS_FEATURE_META_GST_VIDEO_GL_TEXTURE_UPLOAD_META,
"RGBA")
"; " GST_VIDEO_CAPS_MAKE (GST_GL_COLOR_CONVERT_FORMATS))
);
static GstStaticPadTemplate sink_factory = GST_STATIC_PAD_TEMPLATE ("sink_%u",
GST_PAD_SINK,
GST_PAD_REQUEST,
GST_STATIC_CAPS ("video/x-raw(" GST_CAPS_FEATURE_MEMORY_GL_MEMORY "), "
"format = (string) RGBA, "
"width = " GST_VIDEO_SIZE_RANGE ", "
"height = " GST_VIDEO_SIZE_RANGE ", "
"framerate = " GST_VIDEO_FPS_RANGE ","
"texture-target = (string) 2D"
"; "
GST_VIDEO_CAPS_MAKE_WITH_FEATURES
(GST_CAPS_FEATURE_META_GST_VIDEO_GL_TEXTURE_UPLOAD_META,
"RGBA")
"; " GST_VIDEO_CAPS_MAKE (GST_GL_COLOR_CONVERT_FORMATS))
);
static GstFlowReturn gst_gl_stereo_mix_get_output_buffer (GstVideoAggregator *
videoaggregator, GstBuffer ** outbuf);
static gboolean gst_gl_stereo_mix_stop (GstAggregator * agg);
static gboolean gst_gl_stereo_mix_start (GstAggregator * agg);
static gboolean gst_gl_stereo_mix_src_query (GstAggregator * agg,
GstQuery * query);
static void
gst_gl_stereo_mix_find_best_format (GstVideoAggregator * vagg,
GstCaps * downstream_caps, GstVideoInfo * best_info,
gboolean * at_least_one_alpha);
static void gst_gl_stereo_mix_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_gl_stereo_mix_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static void gst_gl_stereo_mix_finalize (GObject * object);
static GstFlowReturn
gst_gl_stereo_mix_aggregate_frames (GstVideoAggregator * vagg,
GstBuffer * outbuffer);
static void
gst_gl_stereo_mix_class_init (GstGLStereoMixClass * klass)
{
GObjectClass *gobject_class = (GObjectClass *) klass;
GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
GstVideoAggregatorClass *videoaggregator_class =
(GstVideoAggregatorClass *) klass;
GstAggregatorClass *agg_class = (GstAggregatorClass *) klass;
GstGLBaseMixerClass *base_mix_class = (GstGLBaseMixerClass *) klass;
GST_DEBUG_CATEGORY_INIT (GST_CAT_DEFAULT, "glstereomixer", 0,
"opengl stereoscopic mixer");
gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_gl_stereo_mix_finalize);
gobject_class->get_property = gst_gl_stereo_mix_get_property;
gobject_class->set_property = gst_gl_stereo_mix_set_property;
gst_element_class_set_metadata (element_class, "OpenGL stereo video combiner",
"Filter/Effect/Video", "OpenGL stereo video combiner",
"Jan Schmidt <jan@centricular.com>");
g_object_class_install_property (gobject_class, PROP_DOWNMIX_MODE,
g_param_spec_enum ("downmix-mode", "Mode for mono downmixed output",
"Output anaglyph type to generate when downmixing to mono",
GST_TYPE_GL_STEREO_DOWNMIX_MODE_TYPE, DEFAULT_DOWNMIX,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&src_factory));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&sink_factory));
agg_class->sinkpads_type = GST_TYPE_GL_STEREO_MIX_PAD;
agg_class->stop = gst_gl_stereo_mix_stop;
agg_class->start = gst_gl_stereo_mix_start;
agg_class->src_query = gst_gl_stereo_mix_src_query;
videoaggregator_class->aggregate_frames = gst_gl_stereo_mix_aggregate_frames;
videoaggregator_class->update_caps = _update_caps;
videoaggregator_class->negotiated_caps = _negotiated_caps;
videoaggregator_class->get_output_buffer =
gst_gl_stereo_mix_get_output_buffer;
videoaggregator_class->find_best_format = gst_gl_stereo_mix_find_best_format;
base_mix_class->supported_gl_api = GST_GL_API_OPENGL | GST_GL_API_OPENGL3;
}
static void
gst_gl_stereo_mix_init (GstGLStereoMix * mix)
{
}
static void
gst_gl_stereo_mix_finalize (GObject * object)
{
//GstGLStereoMix *mix = GST_GL_STEREO_MIX (object);
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static gboolean
gst_gl_stereo_mix_query_caps (GstPad * pad, GstAggregator * agg,
GstQuery * query)
{
GstCaps *filter, *caps;
gst_query_parse_caps (query, &filter);
caps = gst_pad_get_current_caps (agg->srcpad);
if (caps == NULL) {
caps = gst_pad_get_pad_template_caps (agg->srcpad);
}
if (filter)
caps = gst_caps_intersect_full (filter, caps, GST_CAPS_INTERSECT_FIRST);
gst_query_set_caps_result (query, caps);
gst_caps_unref (caps);
return TRUE;
}
static gboolean
gst_gl_stereo_mix_src_query (GstAggregator * agg, GstQuery * query)
{
switch (GST_QUERY_TYPE (query)) {
case GST_QUERY_CAPS:
return gst_gl_stereo_mix_query_caps (agg->srcpad, agg, query);
break;
default:
break;
}
return GST_AGGREGATOR_CLASS (parent_class)->src_query (agg, query);
}
static GstFlowReturn
gst_gl_stereo_mix_get_output_buffer (GstVideoAggregator * videoaggregator,
GstBuffer ** outbuf)
{
GstGLStereoMix *mix = GST_GL_STEREO_MIX (videoaggregator);
GstFlowReturn ret = GST_FLOW_OK;
#if 0
if (!mix->priv->pool_active) {
if (!gst_buffer_pool_set_active (mix->priv->pool, TRUE)) {
GST_ELEMENT_ERROR (mix, RESOURCE, SETTINGS,
("failed to activate bufferpool"), ("failed to activate bufferpool"));
return GST_FLOW_ERROR;
}
mix->priv->pool_active = TRUE;
}
return gst_buffer_pool_acquire_buffer (mix->priv->pool, outbuf, NULL);
#endif
if (!gst_gl_stereo_mix_make_output (mix)) {
gst_buffer_replace (&mix->primary_out, NULL);
gst_buffer_replace (&mix->auxilliary_out, NULL);
GST_ELEMENT_ERROR (mix, RESOURCE, SETTINGS,
("Failed to generate output"), ("failed to generate output"));
ret = GST_FLOW_ERROR;
}
if (mix->auxilliary_out) {
*outbuf = mix->auxilliary_out;
mix->auxilliary_out = NULL;
} else {
*outbuf = mix->primary_out;
mix->primary_out = NULL;
}
return ret;
}
gboolean
gst_gl_stereo_mix_make_output (GstGLStereoMix * mix)
{
GList *walk;
gboolean res = FALSE;
GstElement *element = GST_ELEMENT (mix);
gboolean missing_buffer = FALSE;
GST_LOG_OBJECT (mix, "Processing buffers");
GST_OBJECT_LOCK (mix);
walk = element->sinkpads;
while (walk) {
GstVideoAggregatorPad *vaggpad = walk->data;
GstGLStereoMixPad *pad = walk->data;
GST_LOG_OBJECT (mix, "Checking pad %" GST_PTR_FORMAT, vaggpad);
if (vaggpad->buffer != NULL) {
pad->current_buffer = vaggpad->buffer;
GST_DEBUG_OBJECT (pad, "Got buffer %" GST_PTR_FORMAT,
pad->current_buffer);
} else {
GST_LOG_OBJECT (mix, "No buffer on pad %" GST_PTR_FORMAT, vaggpad);
pad->current_buffer = NULL;
missing_buffer = TRUE;
}
walk = g_list_next (walk);
}
if (missing_buffer) {
/* We're still waiting for a buffer to turn up on at least one input */
GST_WARNING_OBJECT (mix, "Not generating output - need more input buffers");
res = TRUE;
goto out;
}
/* Copy GL memory from each input frame to the output */
if (!gst_gl_stereo_mix_process_frames (mix)) {
GST_LOG_OBJECT (mix, "Failed to process frames to output");
goto out;
}
if (mix->primary_out == NULL)
goto out;
res = TRUE;
out:
GST_OBJECT_UNLOCK (mix);
return res;
}
static GstFlowReturn
gst_gl_stereo_mix_aggregate_frames (GstVideoAggregator * vagg,
GstBuffer * outbuf)
{
GstGLStereoMix *mix = GST_GL_STEREO_MIX (vagg);
/* If we're operating in frame-by-frame mode, push
* the primary view now, and let the parent class
* push the remaining auxilliary view */
if (GST_VIDEO_INFO_MULTIVIEW_MODE (&vagg->info) ==
GST_VIDEO_MULTIVIEW_MODE_FRAME_BY_FRAME) {
/* Transfer the timestamps video-agg put on the aux buffer */
gst_buffer_copy_into (mix->primary_out, outbuf,
GST_BUFFER_COPY_TIMESTAMPS, 0, -1);
gst_aggregator_finish_buffer (GST_AGGREGATOR (vagg), mix->primary_out);
mix->primary_out = NULL;
/* And actually, we don't want timestamps on the aux buffer */
GST_BUFFER_TIMESTAMP (outbuf) = GST_CLOCK_TIME_NONE;
GST_BUFFER_DURATION (outbuf) = GST_CLOCK_TIME_NONE;
}
return GST_FLOW_OK;
}
static void
gst_gl_stereo_mix_get_property (GObject * object,
guint prop_id, GValue * value, GParamSpec * pspec)
{
GstGLStereoMix *mix = GST_GL_STEREO_MIX (object);
switch (prop_id) {
case PROP_DOWNMIX_MODE:
g_value_set_enum (value, mix->downmix_mode);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_gl_stereo_mix_set_property (GObject * object,
guint prop_id, const GValue * value, GParamSpec * pspec)
{
GstGLStereoMix *mix = GST_GL_STEREO_MIX (object);
switch (prop_id) {
case PROP_DOWNMIX_MODE:
mix->downmix_mode = g_value_get_enum (value);
if (mix->viewconvert)
g_object_set_property (G_OBJECT (mix->viewconvert), "downmix-mode",
value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static gboolean
gst_gl_stereo_mix_start (GstAggregator * agg)
{
GstGLStereoMix *mix = GST_GL_STEREO_MIX (agg);
if (!GST_AGGREGATOR_CLASS (parent_class)->start (agg))
return FALSE;
GST_OBJECT_LOCK (mix);
mix->viewconvert = gst_gl_view_convert_new ();
g_object_set (G_OBJECT (mix->viewconvert), "downmix-mode",
mix->downmix_mode, NULL);
GST_OBJECT_UNLOCK (mix);
return TRUE;
}
static gboolean
gst_gl_stereo_mix_stop (GstAggregator * agg)
{
GstGLStereoMix *mix = GST_GL_STEREO_MIX (agg);
if (!GST_AGGREGATOR_CLASS (parent_class)->stop (agg))
return FALSE;
if (mix->viewconvert) {
gst_object_unref (mix->viewconvert);
mix->viewconvert = NULL;
}
return TRUE;
}
/* Convert to caps that can be accepted by this element... */
static GstCaps *
get_converted_caps (GstGLStereoMix * mix, GstCaps * caps)
{
#if 0
GstGLContext *context = GST_GL_BASE_MIXER (mix)->context;
GstCaps *result, *tmp;
GST_LOG_OBJECT (mix, "Converting caps %" GST_PTR_FORMAT, caps);
result = gst_gl_upload_transform_caps (context, GST_PAD_SINK, caps, NULL);
tmp = result;
GST_TRACE_OBJECT (mix, "transfer returned caps %" GST_PTR_FORMAT, tmp);
result =
gst_gl_color_convert_transform_caps (context, GST_PAD_SINK, tmp, NULL);
gst_caps_unref (tmp);
GST_TRACE_OBJECT (mix, "convert returned caps %" GST_PTR_FORMAT, tmp);
tmp = result;
result = gst_gl_view_convert_transform_caps (mix->viewconvert,
GST_PAD_SINK, tmp, NULL);
gst_caps_unref (tmp);
#else
GstCaps *result;
GST_LOG_OBJECT (mix, "Converting caps %" GST_PTR_FORMAT, caps);
result = gst_gl_view_convert_transform_caps (mix->viewconvert,
GST_PAD_SINK, caps, NULL);
#endif
GST_LOG_OBJECT (mix, "returning caps %" GST_PTR_FORMAT, result);
return result;
}
/* Return the possible output caps we decided in find_best_format() */
static GstCaps *
_update_caps (GstVideoAggregator * vagg, GstCaps * caps, GstCaps * filter)
{
GstGLStereoMix *mix = GST_GL_STEREO_MIX (vagg);
return gst_caps_ref (mix->out_caps);
}
/* Called after videoaggregator fixates our caps */
static gboolean
_negotiated_caps (GstVideoAggregator * vagg, GstCaps * caps)
{
GstGLStereoMix *mix = GST_GL_STEREO_MIX (vagg);
GstCaps *in_caps;
GST_LOG_OBJECT (mix, "Configured output caps %" GST_PTR_FORMAT, caps);
if (GST_VIDEO_AGGREGATOR_CLASS (parent_class)->negotiated_caps)
if (!GST_VIDEO_AGGREGATOR_CLASS (parent_class)->negotiated_caps (vagg,
caps))
return FALSE;
/* Update the glview_convert output */
if (!gst_video_info_from_caps (&mix->out_info, caps))
return FALSE;
/* We can configure the view_converter now */
gst_gl_view_convert_set_context (mix->viewconvert,
GST_GL_BASE_MIXER (mix)->context);
in_caps = gst_video_info_to_caps (&mix->mix_info);
gst_caps_set_features (in_caps, 0,
gst_caps_features_from_string (GST_CAPS_FEATURE_MEMORY_GL_MEMORY));
gst_caps_set_simple (in_caps, "texture-target", G_TYPE_STRING,
GST_GL_TEXTURE_TARGET_2D_STR, NULL);
gst_gl_view_convert_set_caps (mix->viewconvert, in_caps, caps);
return TRUE;
}
/* called with the object lock held */
static gboolean
gst_gl_stereo_mix_process_frames (GstGLStereoMix * mixer)
{
GstVideoAggregator *vagg = GST_VIDEO_AGGREGATOR (mixer);
GstBuffer *converted_buffer, *inbuf;
GstVideoInfo *out_info = &vagg->info;
#ifndef G_DISABLE_ASSERT
gint n;
#endif
gint v, views;
gint valid_views = 0;
GList *walk;
inbuf = gst_buffer_new ();
walk = GST_ELEMENT (mixer)->sinkpads;
while (walk) {
GstGLStereoMixPad *pad = walk->data;
GstMemory *in_mem;
GST_LOG_OBJECT (mixer, "Handling frame %d", valid_views);
if (!pad || !pad->current_buffer) {
GST_DEBUG ("skipping texture, null frame");
continue;
}
in_mem = gst_buffer_get_memory (pad->current_buffer, 0);
GST_LOG_OBJECT (mixer,
"Appending memory %" GST_PTR_FORMAT " to intermediate buffer", in_mem);
/* Appending the memory to a 2nd buffer locks it
* exclusive a 2nd time, which will mark it for
* copy-on-write. The ref will keep the memory
* alive but we add a parent_buffer_meta to also
* prevent the input buffer from returning to any buffer
* pool it might belong to
*/
gst_buffer_append_memory (inbuf, in_mem);
/* Use parent buffer meta to keep input buffer alive */
gst_buffer_add_parent_buffer_meta (inbuf, pad->current_buffer);
valid_views++;
walk = g_list_next (walk);
}
if (mixer->mix_info.views != valid_views) {
GST_WARNING_OBJECT (mixer, "Not enough input views to process");
return FALSE;
}
if (GST_VIDEO_INFO_MULTIVIEW_MODE (out_info) ==
GST_VIDEO_MULTIVIEW_MODE_SEPARATED)
views = out_info->views;
else
views = 1;
if (gst_gl_view_convert_submit_input_buffer (mixer->viewconvert,
FALSE, inbuf) != GST_FLOW_OK)
return FALSE;
/* Clear any existing buffers, just in case */
gst_buffer_replace (&mixer->primary_out, NULL);
gst_buffer_replace (&mixer->auxilliary_out, NULL);
if (gst_gl_view_convert_get_output (mixer->viewconvert,
&mixer->primary_out) != GST_FLOW_OK)
return FALSE;
if (GST_VIDEO_INFO_MULTIVIEW_MODE (out_info) ==
GST_VIDEO_MULTIVIEW_MODE_FRAME_BY_FRAME) {
if (gst_gl_view_convert_get_output (mixer->viewconvert,
&mixer->auxilliary_out) != GST_FLOW_OK)
return FALSE;
}
if (mixer->primary_out == NULL)
return FALSE;
converted_buffer = mixer->primary_out;
#ifndef G_DISABLE_ASSERT
n = gst_buffer_n_memory (converted_buffer);
g_assert (n == GST_VIDEO_INFO_N_PLANES (out_info) * views);
#endif
for (v = 0; v < views; v++) {
gst_buffer_add_video_meta_full (converted_buffer, v,
GST_VIDEO_INFO_FORMAT (out_info),
GST_VIDEO_INFO_WIDTH (out_info),
GST_VIDEO_INFO_HEIGHT (out_info),
GST_VIDEO_INFO_N_PLANES (out_info), out_info->offset, out_info->stride);
if (mixer->auxilliary_out) {
gst_buffer_add_video_meta_full (mixer->auxilliary_out, v,
GST_VIDEO_INFO_FORMAT (out_info),
GST_VIDEO_INFO_WIDTH (out_info),
GST_VIDEO_INFO_HEIGHT (out_info),
GST_VIDEO_INFO_N_PLANES (out_info), out_info->offset,
out_info->stride);
}
}
return TRUE;
}
/* Iterate the input sink pads, and choose the blend format
* we will generate before output conversion, which is RGBA
* at some suitable size */
static void
gst_gl_stereo_mix_find_best_format (GstVideoAggregator * vagg,
GstCaps * downstream_caps, GstVideoInfo * best_info,
gboolean * at_least_one_alpha)
{
GstGLStereoMix *mix = GST_GL_STEREO_MIX (vagg);
GList *l;
gint best_width = -1, best_height = -1;
gdouble best_fps = -1, cur_fps;
gint best_fps_n = 0, best_fps_d = 1;
GstVideoInfo *mix_info;
GstCaps *blend_caps, *tmp_caps;
/* We'll deal with alpha internally, so just tell aggregator to
* be quiet */
*at_least_one_alpha = FALSE;
GST_OBJECT_LOCK (vagg);
for (l = GST_ELEMENT (vagg)->sinkpads; l; l = l->next) {
GstVideoAggregatorPad *pad = l->data;
GstVideoInfo tmp = pad->info;
gint this_width, this_height;
gint fps_n, fps_d;
if (!pad->info.finfo)
continue;
/* This can happen if we release a pad and another pad hasn't been negotiated_caps yet */
if (GST_VIDEO_INFO_FORMAT (&pad->info) == GST_VIDEO_FORMAT_UNKNOWN)
continue;
/* Convert to per-view width/height for unpacked forms */
gst_video_multiview_video_info_change_mode (&tmp,
GST_VIDEO_MULTIVIEW_MODE_SEPARATED, GST_VIDEO_MULTIVIEW_FLAGS_NONE);
this_width = GST_VIDEO_INFO_WIDTH (&tmp);
this_height = GST_VIDEO_INFO_HEIGHT (&tmp);
fps_n = GST_VIDEO_INFO_FPS_N (&tmp);
fps_d = GST_VIDEO_INFO_FPS_D (&tmp);
GST_INFO_OBJECT (vagg, "Input pad %" GST_PTR_FORMAT
" w %u h %u", pad, this_width, this_height);
if (this_width == 0 || this_height == 0)
continue;
if (best_width < this_width)
best_width = this_width;
if (best_height < this_height)
best_height = this_height;
if (fps_d == 0)
cur_fps = 0.0;
else
gst_util_fraction_to_double (fps_n, fps_d, &cur_fps);
if (best_fps < cur_fps) {
best_fps = cur_fps;
best_fps_n = fps_n;
best_fps_d = fps_d;
}
/* FIXME: Preserve PAR for at least one input when different sized inputs */
}
GST_OBJECT_UNLOCK (vagg);
mix_info = &mix->mix_info;
gst_video_info_set_format (mix_info, GST_VIDEO_FORMAT_RGBA, best_width,
best_height);
GST_VIDEO_INFO_FPS_N (mix_info) = best_fps_n;
GST_VIDEO_INFO_FPS_D (mix_info) = best_fps_d;
GST_VIDEO_INFO_MULTIVIEW_MODE (mix_info) = GST_VIDEO_MULTIVIEW_MODE_SEPARATED;
GST_VIDEO_INFO_VIEWS (mix_info) = 2;
/* FIXME: If input is marked as flipped or flopped, preserve those flags */
GST_VIDEO_INFO_MULTIVIEW_FLAGS (mix_info) = GST_VIDEO_MULTIVIEW_FLAGS_NONE;
/* Choose our output format based on downstream preferences */
blend_caps = gst_video_info_to_caps (mix_info);
gst_caps_set_features (blend_caps, 0,
gst_caps_features_from_string (GST_CAPS_FEATURE_MEMORY_GL_MEMORY));
tmp_caps = get_converted_caps (GST_GL_STEREO_MIX (vagg), blend_caps);
gst_caps_unref (blend_caps);
if (mix->out_caps)
gst_caps_unref (mix->out_caps);
mix->out_caps = gst_caps_intersect (downstream_caps, tmp_caps);
gst_caps_unref (tmp_caps);
GST_DEBUG_OBJECT (vagg, "Possible output caps %" GST_PTR_FORMAT,
mix->out_caps);
/* Tell videoaggregator our preferred size. Actual info gets
* overridden during caps nego */
*best_info = *mix_info;
}