fix(compression): copy sequence header properly for AV1 packet

[manato]

PR Type

• Bug Fix

Related Links

N/A

Description

This PR fixes how to generate the necessary header information for AV1 keyframes.

Previously, the JetsonAV1Compressor copied the whole first frame to every key frame to make the generated streeam decodable from any key frame.
If the stream is processed by a "spec-faithful" decoder, it generates a blank image for every key frame (, and packing two key frames into one packet, which violates the AV1 specification).

This PR extracts only a portion of information (called "Sequence Header") and copies it to every key frame to secure the specification and make the generated stream decodable from any key frame.

Review Procedure

Execute the followings on a Jetson platform

# publish test pattern (you can install gscam package via `sudo apt install ros-$ROS_DISTRO-gscam`)
$ ros2 run gscam gscam_node \
  --ros-args \
  -p gscam_config:="videotestsrc pattern=18 ! video/x-raw,width=2880,height=1860,frame=2/1"\
  -p camera.image_raw.enable_pub_plugins:=["image_transport/raw"]

# execute AV1 compression
$ ros2 run accelerated_image_processor_ros accelerated_image_processor_ros_imgproc_node \
  --ros-args \
  -r image_raw:=/camera/image_raw \
  -r image_raw/compressed:=/camera/image_raw/compressed \
  -p max_task_length:=5 \
  -p compressor.type:="av1" \
  -p compressor.av1.enable_tile:=false \
  -p rectifier.do_rectify:=false

And visualize compressed data using AV1-compatible lichtblick (which is making in progress): TIER IV INTERNAL

In the previous implementation, blank frames (whole-green images) appear periodically.
After this PR is introduced, they should be gone.

Before	After
acc_pr41_before.mp4	acc_pr41_after.mp4

Remarks

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