Can I compile a HEF with NHCW (native) input layout to skip the NHWC→NHCW conversion?

[optGira]

• Device: Hailo-8L, HailoRT , DFC

• HEF input (parse-hef) is NHWC. Feeding NHWC works.

  The guide says NHCW is the native HW format. My data comes from another device, so I’d like to feed NHCW directly and skip the NHWC→NHCW conversion.

  Tried (InferModel, Python):
  infer_model.input().set_format_order(FormatOrder.NHCW) # also NCHW
  → error: “Unsupported input stream transformation from NHCW to NHWC,
  HAILO_INVALID_OPERATION(6)”

  Questions:

  1. Can the Dataflow Compiler compile a HEF whose host input is NHCW (so no conversion)? If yes, which option controls it?
  2. If not, where does the NHWC→NHCW conversion run — host or NN-Core?

[Klaus_Koschinsky]

@user252

Can the Dataflow Compiler compile a HEF whose host input is NHCW (so no conversion)? If yes, which option controls it?

The raw_stream is usually NHCW format. If not, you can use the following Hailo Dataflow Compiler ALLS command to prevent the addition of the reshape operation:

allocator_param(automatic_reshapes=disabled)

@user252

If not, where does the NHWC→NHCW conversion run — host or NN-Core?

For most models the conversion is run on the host. By default the Hailo Dataflow Compiler will only include it on the device if it has no impact on the FPS.

@user252

My data comes from another device, so I’d like to feed NHCW directly and skip the NHWC→NHCW conversion.

You can use the raw_stream to send data in NHCW format.