v4l2codecs: gstv4l2codecsvp8dec: implement a render delay

The v4l2 backend support delayed output for performance reasons.
It is then possible to use render delays to queue multiple requests
simultaneously, thus increasing performance.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/2150>
This commit is contained in:
Daniel Almeida 2021-04-08 10:11:52 -03:00 committed by Nicolas Dufresne
parent 82c0005793
commit 89bc464360

View file

@ -82,6 +82,24 @@ G_DEFINE_ABSTRACT_TYPE_WITH_CODE (GstV4l2CodecVp8Dec,
"V4L2 stateless VP8 decoder"));
#define parent_class gst_v4l2_codec_vp8_dec_parent_class
static guint
gst_v4l2_codec_vp8_dec_get_preferred_output_delay (GstVp8Decoder * decoder,
gboolean is_live)
{
GstV4l2CodecVp8Dec *self = GST_V4L2_CODEC_VP8_DEC (decoder);
guint delay;
if (is_live)
delay = 0;
else
/* Just one for now, perhaps we can make this configurable in the future. */
delay = 1;
gst_v4l2_decoder_set_render_delay (self->decoder, delay);
return delay;
}
static gboolean
gst_v4l2_codec_vp8_dec_open (GstVideoDecoder * decoder)
{
@ -240,6 +258,7 @@ gst_v4l2_codec_vp8_dec_decide_allocation (GstVideoDecoder * decoder,
{
GstV4l2CodecVp8Dec *self = GST_V4L2_CODEC_VP8_DEC (decoder);
guint min = 0;
guint num_bitstream;
self->has_videometa = gst_query_find_allocation_meta (query,
GST_VIDEO_META_API_TYPE, NULL);
@ -252,8 +271,11 @@ gst_v4l2_codec_vp8_dec_decide_allocation (GstVideoDecoder * decoder,
min = MAX (2, min);
num_bitstream = 1 +
MAX (1, gst_v4l2_decoder_get_render_delay (self->decoder));
self->sink_allocator = gst_v4l2_codec_allocator_new (self->decoder,
GST_PAD_SINK, 2);
GST_PAD_SINK, num_bitstream);
self->src_allocator = gst_v4l2_codec_allocator_new (self->decoder,
GST_PAD_SRC, self->min_pool_size + min + 4);
self->src_pool = gst_v4l2_codec_pool_new (self->src_allocator, &self->vinfo);
@ -850,6 +872,8 @@ gst_v4l2_codec_vp8_dec_subclass_init (GstV4l2CodecVp8DecClass * klass,
GST_DEBUG_FUNCPTR (gst_v4l2_codec_vp8_dec_end_picture);
vp8decoder_class->output_picture =
GST_DEBUG_FUNCPTR (gst_v4l2_codec_vp8_dec_output_picture);
vp8decoder_class->get_preferred_output_delay =
GST_DEBUG_FUNCPTR (gst_v4l2_codec_vp8_dec_get_preferred_output_delay);
klass->device = device;
gst_v4l2_decoder_install_properties (gobject_class, PROP_LAST, device);