So running with the default gstreamer packages on ubuntu
hardy I’ve had image overlay working, with a videomixer with a video
input and an image input, using pngdec. I get a lot
of assertion errors
gst_object_sync_values: assertion `GST_CLOCK_TIME_IS_VALID (timestamp)' failed
, but the png image was overlayed on all video frames.
The pipeline looks like this
filesrc location=logo.png ! pngdec ! alphacolor ! alpha method=0 alpha=0.5 ! videomixer
! decodebin ! ffmpegcolorspace ! alpha method=0 alpha=0.5 ! mixer. !
ffmpegcolorspace ! ffenc_mjpeg ! ffmux_mov ! filesink
Now with the latests stable releases I only get the image
overlayed on the first video frame.
The doc for pngdec states that: “If there is no
framerate set on sink caps, it sends EOS after the first picture.”
So I’ve tried setting the framerate on the sink caps,
but the pngdec still sends eos stream after the first frame and the image only
gets overlayed the first frame….
So my questions is what should I do to have the png image
overlayed on all frames? Is it still possible or
was it just a side effect of something not handled correctly?