<p>I am trying to move an Region of Interest (RoI) around a multi-camera tiled source (which will be too big to encode for smooth viewing), and stream this &quot;live&quot;. The RoI is externally determined which is another problem.</p>
<p>Does anyone have an idea how to achieve this? The solutions I have seen so far require pre-determined RoIs, or potentially change the filter parameters using the libzmq library, but I am not sure if that will be performant enough for a per frame stream.</p>
<p>any help much appreciated!</p>

CC BY-SA 4.0
2022-06-16T04:09:06.523Z
How soon in advance of a frame will you know the RoI?
Gyan
CC BY-SA 4.0
2022-06-16T07:47:59.650Z
Gyan, it will be at the same time, I could in theory add a delay to the start of the output stream if that helps matters, and doesn't lead to desyncing
leelio
<ffmpeg><streaming><filter><live>
can I change ffmpeg crop position at runtime for each frame during stream
leelio
# can I change ffmpeg crop position at runtime for each frame during stream

(Asked by: username_0 on 2022-06-15)

I am trying to move an Region of Interest (RoI) around a multi-camera tiled source (which will be too big to encode for smooth viewing), and stream this "live". The RoI is externally determined which is another problem.

Does anyone have an idea how to achieve this? The solutions I have seen so far require pre-determined RoIs, or potentially change the filter parameters using the libzmq library, but I am not sure if that will be performant enough for a per frame stream.

any help much appreciated!

**Tags:** ffmpeg, streaming, filter, live

> **Comments:**
> **username_1**: How soon in advance of a frame will you know the RoI?  
> **username_0**: username_1, it will be at the same time, I could in theory add a delay to the start of the output stream if that helps matters, and doesn't lead to desyncing  

---

## 0 answers

