v4l2: Display supported framesizes in debug.

modules/access/v4l2.c

@@ -1730,6 +1730,43 @@ vlc_bool_t ProbeVideoDev( demux_t *p_demux, char *psz_device )
                     msg_Dbg( p_demux, "device supports chroma %4s [%s]",
                                 psz_fourcc,
                                 p_sys->p_codecs[i_index].description );
+
+                    /* List valid frame sizes for this format */
+                    struct v4l2_frmsizeenum frmsize;
+                    frmsize.index = 0;
+                    frmsize.pixel_format = p_sys->p_codecs[i_index].pixelformat;
+                    if( ioctl( i_fd, VIDIOC_ENUM_FRAMESIZES, &frmsize ) < 0 )
+                    {
+                        msg_Err( p_demux, "Error while querying for frame size" );
+                    }
+                    else
+                    {
+                        switch( frmsize.type )
+                        {
+                            case V4L2_FRMSIZE_TYPE_DISCRETE:
+                                do
+                                {
+                                    msg_Dbg( p_demux,
+                "device supports size %dx%d",
+                frmsize.discrete.width, frmsize.discrete.height );
+                                    frmsize.index++;
+                                } while( ioctl( i_fd, VIDIOC_ENUM_FRAMESIZES, &frmsize ) >= 0 );
+                                break;
+                            case V4L2_FRMSIZE_TYPE_STEPWISE:
+                                msg_Dbg( p_demux,
+                "device supports sizes %dx%d to %dx%d using %dx%d increments",
+                frmsize.stepwise.min_width, frmsize.stepwise.min_height,
+                frmsize.stepwise.max_width, frmsize.stepwise.max_height,
+                frmsize.stepwise.step_width, frmsize.stepwise.step_height );
+                                break;
+                            case V4L2_FRMSIZE_TYPE_CONTINUOUS:
+                                msg_Dbg( p_demux,
+                "device supports all sizes %dx%d to %dx%d",
+                frmsize.stepwise.min_width, frmsize.stepwise.min_height,
+                frmsize.stepwise.max_width, frmsize.stepwise.max_height );
+                                break;
+                        }
+                    }
                 }
             }
             if( !b_codec_supported )