VPI DCF Tracker outCorrelationResponses

Robotics & Edge Computing Jetson & Embedded Systems Jetson Orin Nano
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1

• Hardware Platform (Jetson / GPU) Jetson Orin Nano
• JetPack Version (valid for Jetson only) 6.2.1
• VPI Version 3.2
• DeepStream Version 7.1
• Issue Type (questions, new requirements, bugs) Questions

I’m experiencing an issue with the VPI DCF Tracker outCorrelationResponses and outMaxCorrelationResponses parameters, it seems these arrays are never populated:

...
CHECK_STATUS(vpiArrayCreate(MAX_TRACKED_TARGETS, VPI_ARRAY_TYPE_DCF_TRACKED_BOUNDING_BOX, 0, &in_targets));
CHECK_STATUS(vpiArrayCreate(MAX_TRACKED_TARGETS, VPI_ARRAY_TYPE_DCF_TRACKED_BOUNDING_BOX, 0, &out_targets));
CHECK_STATUS(vpiImageCreate(dcfInitParams.featurePatchSize, dcfInitParams.featurePatchSize * MAX_TRACKED_TARGETS, VPI_IMAGE_FORMAT_F32, 0, &out_correlations));
CHECK_STATUS(vpiArrayCreate(MAX_TRACKED_TARGETS, VPI_ARRAY_TYPE_F32, 0, &out_max_correlations));
...
CHECK_STATUS(vpiSubmitDCFTrackerLocalizeBatch(stream, 0, dcf, NULL, 0, NULL, patches, in_targets, out_targets, out_correlations, out_max_correlations, NULL));
CHECK_STATUS(vpiStreamSync(stream));
...
CHECK_STATUS(vpiSubmitDCFTrackerUpdateBatch(stream, 0, dcf, NULL, 0, NULL, NULL, patches, targets, NULL));
CHECK_STATUS(vpiStreamSync(stream));
CHECK_VPI_STATUS(vpiArrayLockData(targets, VPI_LOCK_READ, VPI_ARRAY_BUFFER_HOST_AOS, &targets_data));
CHECK_VPI_STATUS(vpiArrayLockData(out_max_correlations, VPI_LOCK_READ, VPI_ARRAY_BUFFER_HOST_AOS, &max_correlation_data));
// Here *targets_data.buffer.aos.sizePointer == 1 but *max_correlation_data.buffer.aos.sizePointer == 0 (even when state == VPI_TRACKING_STATE_TRACKED)
  1. Am I doing something wrong?
  2. Once this works, is outMaxCorrelationResponses actually the confidence to be used when deciding whether tracking is lost?

Thank you in advance.

5

Hi,

Are you able to share more details about your issue?
Is there any error message, or does the algorithm fail to work due to the parameter?

Thanks.

6

Hello @AastaLLL,

Thank you for your reply.

As stated in the above code comments, objects are being tracked - outObjects is being populated and bbox updated, but outCorrelationResponses/outMaxCorrelationResponses aren’t. The function signature is:

VPIStatus vpiSubmitDCFTrackerLocalizeBatch(VPIStream stream, uint64_t backend, VPIPayload payload, const int32_t *enabledSequences, int32_t numSequences, VPIImage featureMaskingWindow, VPIImage inPatches, VPIArray inObjects, VPIArray outObjects, VPIImage outCorrelationResponses, VPIArray outMaxCorrelationResponses, const VPIDCFTrackerParams *params)

Since this seems to be undocumented, can you please explain/verify which conditions can cause outMaxCorrelationResponses to not be populated even though a valid VPIArray is being passed?

Thank you!

7

Hi @AastaLLL,

Any news regarding this?

Thank you!