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Hello all,<br>
<br>
I have a source that produces png images every 500ms and that send
them over UDP:<br>
The command below works as expected (ie the images are properly
displayed):<br>
gst-launch-1.0 udpsrc port=2000 ! pngdec ! videoconvert !
autovideosink<br>
<br>
If I try to convert that stream to mpeg4, with the following
command:<br>
gst-launch-1.0 udpsrc port=2000 ! pngdec ! videoconvert !
avenc_mpeg4 ! udpsink port=5000<br>
<br>
I see (with tcpdump), the input well synchronized with the output. I
believe that is quite normal.<br>
08:51:20.449920 IP 127.0.0.1.35067 > 127.0.1.1.2000: UDP, length
2300<br>
08:51:20.461437 IP 127.0.0.1.58626 > 127.0.0.1.5000: UDP, length
2469<br>
08:51:20.951041 IP 127.0.0.1.35067 > 127.0.1.1.2000: UDP, length
2301<br>
08:51:20.972970 IP 127.0.0.1.58626 > 127.0.0.1.5000: UDP, length
1257<br>
08:51:21.446550 IP 127.0.0.1.35067 > 127.0.1.1.2000: UDP, length
2276<br>
08:51:21.456678 IP 127.0.0.1.58626 > 127.0.0.1.5000: UDP, length
2367<br>
08:51:21.949871 IP 127.0.0.1.35067 > 127.0.1.1.2000: UDP, length
2287<br>
<br>
<b>But I would like to get a 'regular' mpeg4 stream with a 'normal'
framerate...</b><br>
<br>
So I did:<br>
gst-launch-1.0 udpsrc port=2000 ! pngdec ! videorate !
"video/x-raw,framerate=20/1" ! videoconvert ! avenc_mpeg4 ! udpsink
port=5000<br>
or udpsrc port=2000 caps="image/png" ! "image/png,framerate=20/1" !
pngdec ! videoconvert ! avenc_mpeg4 ! udpsink port=5000<br>
<br>
I get the following output:<br>
08:54:<b>23.952456</b> IP 127.0.0.1.35067 > 127.0.1.1.2000: UDP,
length 2325<br>
08:54:23.965143 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
2510<br>
08:54:23.970426 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
163<br>
08:54:23.975527 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
157<br>
08:54:23.981002 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
157<br>
08:54:23.986213 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
157<br>
08:54:23.991431 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
157<br>
08:54:23.996653 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
157<br>
08:54:24.001854 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
157<br>
08:54:24.006957 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
158<br>
08:54:<b>24.012349</b> IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP,
length 157<br>
08:54:<b>24.445583</b> IP 127.0.0.1.35067 > 127.0.1.1.2000: UDP,
length 2291<br>
08:54:24.457157 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
1256<br>
08:54:24.462379 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
166<br>
08:54:24.467513 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
157<br>
08:54:24.474115 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
8153<br>
08:54:24.479420 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
163<br>
08:54:24.484658 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
157<br>
08:54:24.489814 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
157<br>
08:54:24.494858 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
157<br>
08:54:24.500003 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
157<br>
08:54:24.505536 IP 127.0.0.1.44380 > 127.0.0.1.5000: UDP, length
157<br>
08:54:24.957844 IP 127.0.0.1.35067 > 127.0.1.1.2000: UDP, length
2311<br>
<br>
On average it's ok, I have 20 images per seconds ...<br>
<b>HOWEVER, you can see there is a burst of 10 images in ~50ms
after each input then nothing for</b><b>~450ms</b><b><br>
</b><br>
It was clearly not the expected behavior for videorate...<br>
Is there a way to make it smooth or it is a bug ??<br>
<br>
(I do not mention that the command above freeze my computer (it
happens 3 times already) after a while as I didn't try to reproduce
that issue for now).<br>
<br>
Thank you,<br>
Frédéric<br>
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