Gstreamer:动态添加管道中的一个元素时,“src”元素任务将进入暂停状态
我有以下管道:Gstreamer:动态添加管道中的一个元素时,“src”元素任务将进入暂停状态,gstreamer,v4l2,python-gstreamer,Gstreamer,V4l2,Python Gstreamer,我有以下管道: v4l2src -> queue -> h264parse -> avdec_h264 -> identity -> imagefreeze(added/removed dynamically) -> glupload -> glcolorconvert -> gltransformation -> glimagesink 我在元素标识srcpad上添加了一个探针。 根据用户输入,我动态添加或删除元素imagefreeze
v4l2src -> queue -> h264parse -> avdec_h264 -> identity ->
imagefreeze(added/removed dynamically) -> glupload -> glcolorconvert ->
gltransformation -> glimagesink
我在元素标识srcpad上添加了一个探针。
根据用户输入,我动态添加或删除元素imagefreeze
以下是伪代码:
#show live video on rendering window till no user input
#if user_input == 1:
insert_imagefreeze #analogous to image being displayed on rendering window
#if user_input == 2:
delete_imagefreeze #resume back showing live video as before
插入imagefreeze没有问题,它工作正常。我可以通过图像冻结观察到我想要的结果
但是,添加元素imagefreeze后,元素v4l2src任务将进入暂停状态。以下是信息日志:
0:03:39.608226968 [333m29510[00m 0x1561c00 [36mINFO [00m [00m v4l2src gstv4l2src.c:949:gst_v4l2src_create:<source>[00m sync to 0:03:39.066664476 out ts 0:03:39.375180156
0:03:39.608449406 [333m29510[00m 0x1561c00 [36mINFO [00m [00m basesrc gstbasesrc.c:2965:gst_base_src_loop:<source>[00m pausing after gst_pad_push() = eos
0:03:39.608561724 [333m29510[00m 0x1561c00 [36mINFO [00m [00m task gsttask.c:316:gst_task_func:<source:src>[00m Task going to paused.
函数check_和_linksrcpad,sinkpad和check_和_unlinksrcpad,sinkpad只检查src和sink pad,然后相应地链接和取消链接 动态添加imagefreeze时,接收器发送EOS事件。这会使管道进入暂停状态。然而,接收器接收EOS事件的原因仍不清楚,需要进一步调查。提供了更多关于观察结果的信息
def add_delete(self):
if ui_input_cnt = 1 #updated based on user input
self.idsrcpad = self.identity.get_static_pad("src")
self.in_idle_probe = False
self.probeID = self.idsrcpad.add_probe(Gst.PadProbeType.IDLE,self.lengthen_pipeline)
if ui_input_cnt = 2
self.probeID2 = self.idsrcpad.add_probe(Gst.PadProbeType.IDLE,self.shorten_pipeline)
def lengthen_pipeline(self,pad,info):
print("entered callback")
global pipeline
#restrict only 1 call to this callback
if self.in_idle_probe == True:
print("callback for now restricted to one call per thread")
return Gst.PadProbeReturn.OK
if self.in_idle_probe == False:
self.in_idle_probe == True
#create image freze element
self.ifreeze = Gst.ElementFactory.make("imagefreeze","ifreeze")
# increment reference
self.ifreeze.ref()
#add imagefreze to pipeline
pipeline.add(self.ifreeze)
#sync image freeze state to main pipeline
self.ifreeze.sync_state_with_parent()
#unlink identity and upload
#1.get sink pad of upload and srcpad of identity
sinkpad = self.upload.get_static_pad("sink")
srcpad = self.identity.get_static_pad("src")
print("unlinking identit srcpad - uplaod sinkpad")
if self.check_and_unlink(srcpad,sinkpad):
#2.get sink pad of imagefreeze
sinkpad = self.ifreeze.get_static_pad("sink")
#3. link identity src pad to image freeze sinkpad
print("linking identity srcpad - ifreeze sinkpad")
self.check_and_link(srcpad,sinkpad)
#4. link imagefreeze src pad to upload sink pad
#get image freeze srcpad and sinkpad of upload
srcpad = self.ifreeze.get_static_pad("src")
sinkpad = self.upload.get_static_pad("sink")
print("linking ifreeze srcpad - upload sinkpad")
if self.check_and_link(srcpad,sinkpad):
return Gst.PadProbeReturn.REMOVE
else:
print("ERORR : unlinking")
return -1