Align the output of Pgie before infered by the Sgie

[damonzzz]

Please provide complete information as applicable to your setup.

• Hardware Platform GPU
• DeepStream Version 6.1
• Issue Type questions
Hi,
I’m trying to do an alignment of pgie’s output before it gets into sgie. As I know, there are topics and requests about this function since 2020. Here are links: 1, 2.

I notice that ver 6.1 has a new feature: gst-nvdspreprocess, I’m wondering if the alignment is supported in the latest version. Or can I write a custom plugin at the top of nvdspreprocess to achieve alignment?

Hope you guys can give me some advice :-)

thanks in advance.

[fanzh]

please refer to How to send a custom crop to sgie input? - #3

[damonzzz]

@fanzh thanks for quick reply, I’ve read the link you gave.

So, there is no official way to align the output before sige. Can I modify the nvdspreprocess to achieve this goal? While I read the codes, I find alignment is very similar to cropping. If I get the output result, bbox and landmarks for example, then can I use them to do alignment in the modified nvdspreprocess by cropping and aligning the frames? then I add them into the batch as your annotation:

/* Adding a Unit (ROI/Crop/Full Frame) to the current batch. Set the frames members. */

What do you think of this method?

[fanzh]

nvdspreprocess and nvinfer are both opensource.
nvdspreprocess will generate NvDsPreProcessTensorMeta after processing the full frame, then send it to pgie. you can modify nvdspreprocess to generate new NvDsPreProcessTensorMeta, then send tensormeta to sgie.