diff options
| -rw-r--r-- | gst/compositor/compositor.c | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/gst/compositor/compositor.c b/gst/compositor/compositor.c index ef71d841b..357dd4b6c 100644 --- a/gst/compositor/compositor.c +++ b/gst/compositor/compositor.c @@ -296,6 +296,17 @@ gst_compositor_pad_set_info (GstVideoAggregatorPad * pad, return TRUE; } +/* Test whether rectangle2 contains rectangle 1 (geometrically) */ +static gboolean +is_rectangle_contained (GstVideoRectangle rect1, GstVideoRectangle rect2) +{ + if ((rect2.x <= rect1.x) && (rect2.y <= rect1.y) && + ((rect2.x + rect2.w) >= (rect1.x + rect1.w)) && + ((rect2.y + rect2.h) >= (rect1.y + rect1.h))) + return TRUE; + return FALSE; +} + static gboolean gst_compositor_pad_prepare_frame (GstVideoAggregatorPad * pad, GstVideoAggregator * vagg) @@ -307,6 +318,11 @@ gst_compositor_pad_prepare_frame (GstVideoAggregatorPad * pad, GstVideoFrame *frame; static GstAllocationParams params = { 0, 15, 0, 0, }; gint width, height; + gboolean frame_obscured = FALSE; + GList *l; + /* The rectangle representing this frame, clamped to the video's boundaries. + * Due to the clamping, this is different from the frame width/height above. */ + GstVideoRectangle frame_rect; if (!pad->buffer) return TRUE; @@ -319,6 +335,17 @@ gst_compositor_pad_prepare_frame (GstVideoAggregatorPad * pad, return FALSE; } + /* There's three types of width/height here: + * 1. GST_VIDEO_FRAME_WIDTH/HEIGHT: + * The frame width/height (same as pad->buffer_vinfo.height/width; + * see gst_video_frame_map()) + * 2. cpad->width/height: + * The optional pad property for scaling the frame (if zero, the video is + * left unscaled) + * 3. conversion_info.width/height: + * Equal to cpad->width/height if it's set, otherwise it's the frame + * width/height. See ->set_info() + * */ if (cpad->width > 0) width = cpad->width; else @@ -394,6 +421,60 @@ gst_compositor_pad_prepare_frame (GstVideoAggregatorPad * pad, g_free (wanted_colorimetry); } + /* Clamp the x/y coordinates of this frame to the video boundaries to cover + * the case where (say, with negative xpos/ypos) the non-obscured portion of + * the frame could be outside the bounds of the video itself and hence not + * visible at all */ + frame_rect.x = CLAMP (cpad->xpos, 0, + GST_VIDEO_INFO_WIDTH (&pad->buffer_vinfo)); + frame_rect.y = CLAMP (cpad->ypos, 0, + GST_VIDEO_INFO_HEIGHT (&pad->buffer_vinfo)); + /* Clamp the width/height to the frame boundaries as well */ + frame_rect.w = MIN (GST_VIDEO_INFO_WIDTH (&cpad->conversion_info), + GST_VIDEO_INFO_WIDTH (&pad->buffer_vinfo) - cpad->xpos); + frame_rect.h = MIN (GST_VIDEO_INFO_HEIGHT (&cpad->conversion_info), + GST_VIDEO_INFO_HEIGHT (&pad->buffer_vinfo) - cpad->ypos); + + GST_OBJECT_LOCK (vagg); + /* Check if this frame is obscured by a higher-zorder frame + * TODO: Also skip a frame if it's obscured by a combination of + * higher-zorder frames */ + for (l = g_list_find (GST_ELEMENT (vagg)->sinkpads, pad)->next; l; + l = l->next) { + GstVideoRectangle frame2_rect; + GstVideoAggregatorPad *pad2 = l->data; + GstCompositorPad *cpad2 = GST_COMPOSITOR_PAD (pad2); + + /* We don't need to clamp the coords of the second rectangle */ + frame2_rect.x = cpad2->xpos; + frame2_rect.y = cpad2->ypos; + /* This is effectively what set_info and the above conversion + * code do to calculate the desired width/height */ + frame2_rect.w = cpad2->width ? cpad2->width : + GST_VIDEO_INFO_WIDTH (&cpad2->conversion_info); + frame2_rect.h = cpad2->height ? cpad2->height : + GST_VIDEO_INFO_HEIGHT (&cpad2->conversion_info); + + /* Check if there's a buffer to be aggregated, ensure it can't have an alpha + * channel, then check opacity and frame boundaries */ + if (pad2->buffer && cpad2->alpha == 1.0 && + !GST_VIDEO_INFO_HAS_ALPHA (&pad2->info) && + is_rectangle_contained (frame_rect, frame2_rect)) { + frame_obscured = TRUE; + GST_DEBUG_OBJECT (pad, "Obscured by %s, skipping frame", + GST_PAD_NAME (pad2)); + break; + } + } + GST_OBJECT_UNLOCK (vagg); + + if (frame_obscured) { + converted_frame = NULL; + gst_video_frame_unmap (frame); + g_slice_free (GstVideoFrame, frame); + goto done; + } + if (cpad->alpha == 0.0) { GST_DEBUG_OBJECT (vagg, "Pad has alpha 0.0, not converting frame"); converted_frame = NULL; @@ -428,6 +509,7 @@ gst_compositor_pad_prepare_frame (GstVideoAggregatorPad * pad, converted_frame = frame; } +done: pad->aggregated_frame = converted_frame; return TRUE; @@ -808,6 +890,8 @@ gst_compositor_aggregate_frames (GstVideoAggregator * vagg, GstBuffer * outbuf) outframe = &out_frame; /* default to blending */ composite = self->blend; + /* TODO: If the frames to be composited completely obscure the background, + * don't bother drawing the background at all. */ switch (self->background) { case COMPOSITOR_BACKGROUND_CHECKER: self->fill_checker (outframe); |