Getting Camera Time though aravissrc gst plugin

Using Aravis
1

Hi ,
I am using aravissrc gst plugin to fully access cam functionality of Baumer VCXU-2.32C camera.
Few queries related to timestamp attachment in gst pipelines.
When “do-timestamp“ is enabled , aravissrc attaches current monotonic time , and when it is disabled, timestamp is decoded through

timestamp_ns = arv_buffer_get_timestamp (arv_buffer);
if (!base_src_does_timestamp) {
if (gst_aravis->timestamp_offset == 0) {
gst_aravis->timestamp_offset = timestamp_ns;
gst_aravis->last_timestamp = timestamp_ns;
}
GST_BUFFER_PTS (*buffer) = timestamp_ns - gst_aravis->timestamp_offset;
GST_BUFFER_DURATION (*buffer) = timestamp_ns - gst_aravis->last_timestamp;
gst_aravis->last_timestamp = timestamp_ns;
}

i was wondering why the timestamp offset (first frame time) is subtracted here .
is the PTS time with respect to the first frame that aravissrc gets?
I am basically trying to get the camera time which comes along with Chunk Data when ChunkModeActive=1
ChunkSelector=Timestamp
ChunkEnable=1
Thanks.

2

Hi,

This code was written a long time ago, being mostly an adaptation of an existing plugin. I’m pretty sure I did not think much about the meaning of the buffer timestamp. I guess the buffer timestamp of a live stream must start with 0, but I’m not sure.

That should normally be the same as the timestamp of a buffer without chunk mode enabled. For what purpose do you want this timestamp ?