[Spice-devel] [spice-gtk] gstreamer: Take into account stride information

[Pavel Grunt]

On Tue, 2017-07-25 at 10:50 -0400, Frediano Ziglio wrote:
> > 
> > Hi Frediano,
> > 
> > On Tue, 2017-07-25 at 15:31 +0100, Frediano Ziglio wrote:
> > > Using hardware encoders/decoders is possible that the output
> > > stride of the image cannot be computed with a fixed formula
> > > (width * 4). GStreamer in this case should set GstVideoMeta
> > > information with the correct stride value.
> > > Consider this value if present.
> > > This fix a problem using NvDec encoder and Intel decoder.
> > 
> > you mean NVENC encoder
> > 
> 
> correct :)
> 
> > > 
> > > Signed-off-by: Frediano Ziglio <fziglio at redhat.com>
> > > ---
> > >  src/channel-display-gst.c   | 9 ++++++++-
> > >  src/channel-display-mjpeg.c | 2 +-
> > >  src/channel-display-priv.h  | 2 +-
> > >  src/channel-display.c       | 6 ++++--
> > >  4 files changed, 14 insertions(+), 5 deletions(-)
> > > 
> > > diff --git a/src/channel-display-gst.c b/src/channel-display-gst.c
> > > index 03c6044..0abe706 100644
> > > --- a/src/channel-display-gst.c
> > > +++ b/src/channel-display-gst.c
> > > @@ -26,6 +26,7 @@
> > >  #include <gst/gst.h>
> > >  #include <gst/app/gstappsrc.h>
> > >  #include <gst/app/gstappsink.h>
> > > +#include <gst/video/gstvideometa.h>
> > >  
> > >  
> > >  /* GStreamer decoder implementation */
> > > @@ -102,6 +103,12 @@ static void free_gst_frame(SpiceGstFrame *gstframe)
> > >  
> > >  static void schedule_frame(SpiceGstDecoder *decoder);
> > >  
> > > +static int gst_buffer_get_stride(GstBuffer *buffer)
> > 
> > I'd prefer to do in our namespace instead on gstreamer's
> > > +{
> > > +    GstVideoMeta *video = gst_buffer_get_video_meta(buffer);
> > > +    return video ? video->stride[0] : 0;
> > 
> > The documentation of GstVideoMeta says that the value of the stride may be
> > invalid - do you know what is the value in that case?
> > 
> > What about using some constant instead of 0 (respectively the invalid value)
> > (SPICE_UNKNOWN_STRIDE)
> > 
> 
> No idea the gstreamer invalid value. Maybe n_planes == 0 ?
> Where do you suggest to define it?
> 
> #define SPICE_UNKNOWN_STRIDE 0
> 
> in src/channel-display-priv.h ?
> 
yes

> > 
> > > +}
> > > +
> > >  /* main context */
> > >  static gboolean display_frame(gpointer video_decoder)
> > >  {
> > > @@ -145,7 +152,7 @@ static gboolean display_frame(gpointer video_decoder)
> > >      }
> > >  
> > >      stream_display_frame(decoder->base.stream, gstframe->frame,
> > > -                         width, height, mapinfo.data);
> > > +                         width, height, gst_buffer_get_stride(buffer),
> > > mapinfo.data);
> > >      gst_buffer_unmap(buffer, &mapinfo);
> > >  
> > >   error:
> > > diff --git a/src/channel-display-mjpeg.c b/src/channel-display-mjpeg.c
> > > index 3ba098c..6082511 100644
> > > --- a/src/channel-display-mjpeg.c
> > > +++ b/src/channel-display-mjpeg.c
> > > @@ -176,7 +176,7 @@ static gboolean mjpeg_decoder_decode_frame(gpointer
> > > video_decoder)
> > >  
> > >      /* Display the frame and dispose of it */
> > >      stream_display_frame(decoder->base.stream, decoder->cur_frame,
> > > -                         width, height, decoder->out_frame);
> > > +                         width, height, 0, decoder->out_frame);
> > 
> > same here
> > 
> > >      free_spice_frame(decoder->cur_frame);
> > >      decoder->cur_frame = NULL;
> > >      decoder->timer_id = 0;
> > > diff --git a/src/channel-display-priv.h b/src/channel-display-priv.h
> > > index 04cb4d1..72e0840 100644
> > > --- a/src/channel-display-priv.h
> > > +++ b/src/channel-display-priv.h
> > > @@ -192,7 +192,7 @@ G_STATIC_ASSERT(G_N_ELEMENTS(gst_opts) <=
> > > SPICE_VIDEO_CODEC_TYPE_ENUM_END);
> > >  
> > >  guint32 stream_get_time(display_stream *st);
> > >  void stream_dropped_frame_on_playback(display_stream *st);
> > > -void stream_display_frame(display_stream *st, SpiceFrame *frame, uint32_t
> > > width, uint32_t height, uint8_t* data);
> > > +void stream_display_frame(display_stream *st, SpiceFrame *frame, uint32_t
> > > width, uint32_t height, int stride, uint8_t* data);
> > >  gint64 get_stream_id_by_stream(SpiceChannel *channel, display_stream
> > > *st);
> > >  
> > >  
> > > diff --git a/src/channel-display.c b/src/channel-display.c
> > > index 06ed18a..4eb665f 100644
> > > --- a/src/channel-display.c
> > > +++ b/src/channel-display.c
> > > @@ -1312,9 +1312,11 @@ void
> > > stream_dropped_frame_on_playback(display_stream
> > > *st)
> > >  /* main context */
> > >  G_GNUC_INTERNAL
> > >  void stream_display_frame(display_stream *st, SpiceFrame *frame,
> > > -                          uint32_t width, uint32_t height, uint8_t *data)
> > > +                          uint32_t width, uint32_t height, int stride,
> > > uint8_t *data)
> > >  {
> > > -    int stride = width * sizeof(uint32_t);
> > > +    if (stride == 0) {
> > 
> > and here
> > > +        stride = width * sizeof(uint32_t);
> > > +    }
> > >      if (!(st->flags & SPICE_STREAM_FLAGS_TOP_DOWN)) {
> > >          data += stride * (height - 1);
> > >          stride = -stride;
> 
> Frediano