Table of Contents

1 Overview

The primary goal of this Design is to demonstrate the capabilities of VCU hard block present in Zynq UltraScale+ EV devices. The TRD will serve as a platform to tune the performance parameters of VCU and arrive at optimal configurations for encoder and decoder blocks with the streaming use case where bandwidth plays a vital role. 10G will give sufficient bandwidth for the streaming protocol to play video pipeline smoothly.

This design supports the following video interfaces:

Sources:

HDMI-Rx capture pipeline implemented in the PL.
File source (SD card, USB storage, SATA hard disk).
Stream-In from network or internet.

Sinks:

HDMI-Tx display pipeline implemented in the PL.

VCU Codec:

Video Encode/Decode capability using VCU hard block in PL
- AVC/HEVC encoding.
- Encoder/decoder parameter configuration.

Streaming Interfaces:

10G Ethernet on PL
1G Ethernet on PS

Video format:

NV12

10G Deliverables:

Pipeline	Input source	Output Type	Resolution	Video encode/Decoder type	Deliverables
Record/Stream-Out pipeline	HDMI-Rx	File Sink/ Stream-Out	4K/1080p	HEVC/AVC	HDMI Rx Video encodes with VCU and stores it in a container format.
Playback pipeline	File Source/ Stream-In	HDMI –Tx	4K/1080p	HEVC/AVC	Playback of the local-file/stream-in with video decoded using VCU and display on HDMI-Tx.
Capture--> Display	HDMI-Rx	HDMI -Tx	4K/1080p	HEVC/AVC	HDMI Rx Video passes to HDMI-Tx without VCU.
Capture--> Encode--> Decode--> Display	HDMI-Rx	HDMI -Tx	4K/1080p	HEVC/AVC	HDMI Rx raw video passes through VCU elements encoder and decoder and finally displays on HDMI-Tx.

Supported Resolution:

The table below provides the supported resolution in this design.

Resolution	Command Line
Resolution	Single Stream	Multi-stream
4kp60	√	NA
4kp30	√	NA
1080p60	√	NA

√ - Supported
NA – Not applicable
x – Not supported

The below figure shows the TRD block diagram.

The below sections describe the 10G HDMI Video Capture and HDMI Display design. It is VCU TRD design supporting 10G HDMI-Rx and HDMI-Tx. For the overview, software tools, system requirements and design files follow the link below:

Zynq UltraScale+ MPSoC VCU TRD 2019.2

The below figure shows the 10G HDMI Video Capture and HDMI Display design hardware block diagram.

The below figure shows the 10G HDMI Video Capture and HDMI Display design software block diagram.

1.1 Board Setup

Refer below link for Board Setup

Zynq UltraScale+ MPSoC VCU TRD 2019.2 Board Setup

Board Connections:

The figure shows the ZCU106 board connections for 10G HDMI-Rx and HDMI-Tx Streaming support

1.2 Run Flow

The TRD package is released with the source code, Vivado project, Petalinux BSP, and SD card image that enables the user to run the demonstration. It also includes the binaries necessary to configure and boot the ZCU106 board. Prior to running the steps mentioned in this wiki page, download the TRD package and extract its contents to a directory referred to as ‘TRD_HOME' which is the home directory.

Refer below link to download all TRD contents.

Zynq UltraScale+ MPSoC VCU TRD 2019.2 Download zip

TRD package contents are placed in the following directory structure. The user needs to copy all the files from the $TRD_HOME/images/vcu_10g/ to FAT32 formatted SD card directory.

└── rdf0428-zcu106-vcu-trd-2019-2
	├── apu
	│   └── vcu_petalinux_bsp
	├── images
	│   ├── vcu_10g
	│   ├── vcu_audio
	│   ├── vcu_hdmi_multistream_xv20
	│   ├── vcu_hdmi_rx
	│   ├── vcu_hdmi_tx
	│   ├── vcu_llp2_hdmi_nv12
	│   ├── vcu_llp2_hdmi_nv16
	│   ├── vcu_llp2_hdmi_xv20
	│   ├── vcu_llp2_sdi_xv20
	│   ├── vcu_multistream_nv12
	│   ├── vcu_pcie
	│   ├── vcu_sdirx
	│   ├── vcu_sditx
	│   └── vcu_sdi_xv20
	├── pcie_host_package
	│   ├── COPYING
	│   ├── etc
	│   ├── include
	│   ├── libxdma
	│   ├── LICENSE
	│   ├── README.md
	│   ├── tools
	│   └── xdma
	├── pl
	│   ├── constrs
	│   ├── designs
	│   ├── prebuild
	│   ├── README.md
	│   └── srcs
	└── README.txt

TRD package contents specific to 10G HDMI Video Capture and HDMI Display design is placed in the following directory structure.

rdf0428-zcu106-vcu-trd-2019-2
├── apu
│   └── vcu_petalinux_bsp
│       └── xilinx-vcu-zcu106-v2019.2-final.bsp
├── images
│   ├── vcu_10g
│   │   ├── autostart.sh
│   │   ├── bin
│   │   ├── BOOT.BIN
│   │   ├── config
│   │   ├── image.ub
│   │   ├── system.dtb
│   │   └── vcu
├── pcie_host_package
├── pl
│   ├── constrs
│   ├── designs
│   │   ├── zcu106_10g
│   ├── prebuild
│   │   ├── zcu106_10g
│   ├── README.md
│   └── srcs
│       ├── hdl
│       └── ip
└── README.txt

configuration files(input.cfg) for various Resolutions are placed in the following directory structure in /media/card.

config/
├── 4kp60
│   ├── Display
│   ├── Record
│   ├── Stream-out
│   └── Stream-in
├── 4kp30
│   ├── Display 
│   ├── Record 
│   ├── Stream-out
│   └── Stream-in 
├── 1080p60 
│   ├── Display 
│   ├── Record 
│   ├── Stream-out
│   └── Stream-in 
└── input.cfg

1.2.1 GStreamer Application (vcu_gst_app)

The vcu_gst_app is a command-line multi-threaded Linux application. The command-line application requires an input configuration file (input.cfg) to be provided in plain text.

Execution of the application is shown below:

% vcu_gst_app < path to *.cfg file>

Example:

4kp60 HEVC_HIGH Display Pipeline execution

% vcu_gst_app /media/card/config/4kp60/Display/Single_4kp60_HEVC_HIGH.cfg

4kp60 HEVC_HIGH Record Pipeline execution

% vcu_gst_app /media/card/config/4kp60/Record/Single_4kp60_HEVC_HIGH.cfg

4kp60 HEVC_HIGH Stream-out Pipeline execution

% vcu_gst_app /media/card/config/4kp60/Stream-out/Single_4kp60_HEVC_HIGH.cfg

4kp60 HEVC_HIGH Stream-in Pipeline execution

% vcu_gst_app /media/card/config/4kp60/Stream-in/input.cfg

NOTE: Make sure HDMI-Rx should be configured to 4kp60 mode.

To measure the latency of the pipeline, run the below command. The latency data is huge, so dump it to a file.

% GST_DEBUG="GST_TRACER:7" GST_TRACERS="latency;scheduletime" ./vcu_gst_app ./input.cfg >& dump_log.txt

Refer below link for detailed run flow steps

Zynq UltraScale+ MPSoC VCU TRD 2019.2 - Run Flow

1.3 Build Flow

Refer below link for Build Flow

Zynq UltraScale+ MPSoC VCU TRD 2019.2 - Build Flow

2 Other Information

2.1 Known Issues

For Petalinux related known issues please refer AR# 72950: PetaLinux 2019.2 - Product Update Release Notes and Known Issues.
For VCU related known issues please refer AR# 66763: LogiCORE H.264/H.265 Video Codec Unit (VCU) - Release Notes and Known Issues and Xilinx Zynq UltraScale+ MPSoC Video Codec Unit.

2.2 Limitations

For Petalinux related limitations please refer AR# 72950: PetaLinux 2019.2 - Product Update Release Notes and Known Issues.
For VCU related limitations please refer AR# 66763: LogiCORE H.264/H.265 Video Codec Unit (VCU) - Release Notes and Known Issues, Xilinx Zynq UltraScale+ MPSoC Video Codec Unit and PG252 link.

2.3 Optimum VCU Encoder parameters for use-cases:

Video streaming:

Video streaming use-case requires a very stable bitrate graph for all pictures.
It is good to avoid periodic large Intra pictures during the encoding session
Low-latency rate control (hardware RC) is the preferred control-rate for video streaming, it tries to maintain equal amount frame sizes for all pictures.
Good to avoid periodic Intra frames instead use low-delay-p (IPPPPP…)
VBR is not a preferred mode of streaming.

Performance: AVC Encoder settings:

It is preferred to use 8 or higher slices for better AVC encoder performance.
AVC standard does not support Tile mode processing which results in the processing of MB rows sequentially for entropy coding.

Quality: Low bitrate AVC encoding:

Enable profile=high and use qp-mode=auto for low-bitrate encoding use-cases.
The high profile enables 8x8 transform which results in better video quality at low bitrates.

3 Appendix A - Input Configuration File (input.cfg)

The example configuration files are stored at /media/card/config/ folder.

Common Configuration:
It is the starting point of common configuration.

Num of Input:
Provide the number of inputs. this is always 1 for this design.

Output:
Select the video interface.
Options: HDMI or DP

Out Type:
Options: display, record, and stream

Display Rate:
Pipeline frame rate.
Options: 30 FPS or 60 FPS for each stream.

Exit:
It indicates to the application that the configuration is over.

Input Configuration:
It is the starting point of the input configuration.

Input Num:
Starting Nth input configuration.
Options: 1

Input Type:
Input source type.
Options: HDMI, File, Stream

Uri:
File path or Network URL. Applicable for file playback and stream-in pipeline only. Supported file formats for playback are ts, mp4, and mkv.
NOTE: For 10G HDMI Options: file:///media/usb/abc.ts (for file path), udp://192.168.26.89:5004/ (for Network streaming, Here 192.168.26.89 is 10G IP address and 5004 is port no)
For 1G HDMI Options: file:///media/usb/abc.ts (for file path), udp://192.168.25.89:5004/ (for Network streaming, Here 192.168.25.89 is the 1G IP address and 5004 is port no)

Raw:
To tell the pipeline is processed or pass-through.
Options: True, False

Width:
The width of the live source.
Options: 3840, 1920

Height:
The height of the live source.
Options: 2160, 1080

Exit:
It indicates to the application that the configuration is over.

Encoder Configuration:
It is the starting point of encoder configuration.

Encoder Num:
Starting Nth encoder configuration.
Options: 1

Encoder Name:
Name of the encoder.
Options: AVC, HEVC

Profile:
Name of the profile.
Options: baseline, main or high for AVC. Main for HEVC.

Rate Control:
Rate control options.
Options: CBR, VBR, and low-latency.

Filler Data:
Filler Data NAL units for CBR rate control.
Options: True, False

QP:
QP control mode used by the VCU encoder.
Options: Uniform, Auto

L2 Cache:
Enable or Disable L2Cache buffer in encoding process.
Options: True, False

Latency Mode:
Encoder latency mode.
Options: normal, sub_frame

Low Bandwidth:
If enabled, decrease the vertical search range used for P-frame motion estimation to reduce the bandwidth.
Options: True, False

Gop Mode:
Group of Pictures mode.
Options: Basic, low_delay_p, low_delay_b

Bitrate:
Target bitrate in Kbps
Options: 1-60000

B Frames:
Number of B-frames between two consecutive P-frames
Options: 0-4

Slice:
The number of slices produced for each frame. Each slice contains one or more complete macroblock/CTU row(s). Slices are distributed over the frame as regularly as possible. If slice-size is defined as well more slices may be produced to fit the slice-size requirement.
Options:
4-22 4kp resolution with HEVC codec
4-32 4kp resolution with AVC codec
4-32 1080p resolution with HEVC codec
4-32 1080p resolution with AVC codec

GoP Length:
The distance between two consecutive I frames
Options: 1-1000

Format:
The format of input data.
Options: NV12

Preset:
Options: HEVC_HIGH, HEVC_MEDIUM, HEVC_LOW, AVC_HIGH, AVC_MEDIUM, AVC_LOW, Custom

Exit
It indicates to the application that the configuration is over.

Record Configuration:
It is the starting point of record configuration.

Record Num:
Starting Nth record configuration.
Options: 1

Out-File Name:
Record file path.
Options: /media/usb/abc.ts

Duration:
Duration in minutes.
Options: 1-3

Exit
It indicates to the application that the configuration is over.

Streaming Configuration:
It is the starting point of streaming configuration.

Streaming Num:
Starting Nth Streaming configuration.
Options: 1.

Host IP:
The host to send the packets to
Note: For 10G- Options: 192.168.26.89 or Windows PC IP
Note: For 1G- Options: 192.168.25.89 or Windows PC IP

Port:
The port to send the packets to
Options: 5004,5008,5012 and 5016.

Exit
It indicates to the application that the configuration is over.

Trace Configuration:
It is the starting point of trace configuration.

FPS Info:
To display fps info on the console.
Options: True, False

APM Info:
To display the APM counter number on the console.
Options: True, False

Pipeline Info:
To display pipeline info on console.
Options: True, False

Exit
It indicates to the application that the configuration is over.

4 Appendix B

To check the link status, resolution and video node of HDMI input source, run below xmedia-ctl command.

$ xmedia-ctl -p -d /dev/media0

When HDMI source is connected to 4KP60 resolution, it shows:

root@zcu106_vcu_trd:/media/card# xmedia-ctl -p -d /dev/media0
Media controller API version 4.19.0

Media device information
------------------------
driver          xilinx-video
model           Xilinx Video Composite Device
serial          
bus info        
hw revision     0x0
driver version  4.19.0

Device topology
- entity 1: vcap_hdmi output 0 (1 pad, 1 link)
            type Node subtype V4L flags 0
            device node name /dev/video0 -----> Video node for HDMI Rx source
        pad0: Sink
                <- "a0080000.v_proc_ss":1 [ENABLED]

- entity 5: a0080000.v_proc_ss (2 pads, 2 links)
            type V4L2 subdev subtype Unknown flags 0
            device node name /dev/v4l-subdev0
        pad0: Sink
                [fmt:VYYUYY8_1X24/3840x2160 field:none]
                <- "a0000000.v_hdmi_rx_ss":0 [ENABLED]
        pad1: Source
                [fmt:VYYUYY8_1X24/3840x2160 field:none]
                -> "vcap_hdmi output 0":0 [ENABLED]

- entity 8: a0000000.v_hdmi_rx_ss (1 pad, 1 link)
            type V4L2 subdev subtype Unknown flags 0
            device node name /dev/v4l-subdev1
        pad0: Source
                [fmt:VYYUYY8_1X24/3840x2160 field:none colorspace:rec709]
                [dv.caps:BT.656/1120 min:0x0@25000000 max:4096x2160@297000000 stds:CEA-861,DMT,CVT,GTF caps:progressive,reduced-blanking,custo]
                [dv.detect:BT.656/1120 3840x2160p60 (4400x2250) stds:CEA-861 flags:CE-video] -----> Resolution and Frame-rate of HDMI Rx source 
                -> "a0080000.v_proc_ss":0 [ENABLED]

NOTE: Check resolution and frame-rate of "dv.detect" under "v_hdmi_rx_ss" node.

When the HDMI source is not connected, it shows:

root@zcu106_vcu_trd:/media/card# xmedia-ctl -p -d /dev/media0
Media controller API version 4.19.0

Media device information
------------------------
driver          xilinx-video
model           Xilinx Video Composite Device
serial          
bus info        
hw revision     0x0
driver version  4.19.0

Device topology
- entity 1: vcap_hdmi output 0 (1 pad, 1 link)
            type Node subtype V4L flags 0
            device node name /dev/video0 -----> Video node for HDMI Rx source
        pad0: Sink
                <- "a0080000.v_proc_ss":1 [ENABLED]

- entity 5: a0080000.v_proc_ss (2 pads, 2 links)
            type V4L2 subdev subtype Unknown flags 0
            device node name /dev/v4l-subdev0
        pad0: Sink
                [fmt:VYYUYY8_1X24/3840x2160 field:none]
                <- "a0000000.v_hdmi_rx_ss":0 [ENABLED]
        pad1: Source
                [fmt:VYYUYY8_1X24/3840x2160 field:none]
                -> "vcap_hdmi output 0":0 [ENABLED]

- entity 8: a0000000.v_hdmi_rx_ss (1 pad, 1 link)
            type V4L2 subdev subtype Unknown flags 0
            device node name /dev/v4l-subdev1
        pad0: Source
                [fmt:VYYUYY8_1X24/3840x2160 field:none colorspace:rec709]
                [dv.caps:BT.656/1120 min:0x0@25000000 max:4096x2160@297000000 stds:CEA-861,DMT,CVT,GTF caps:progressive,reduced-blanking,custo]
                [dv.query:no-link] -----> HDMI Rx Link Status
                -> "a0080000.v_proc_ss":0 [ENABLED]

NOTE: Here "dv.query:no-link" under "v_hdmi_rx_ss" node shows HDMI-Rx source is not connected or HDMI-Rx source is not active(Try waking up the device by pressing the key on remote).

Notes for gst-launch-1.0 commands:

Make sure the HDMI-Rx media pipeline is configured for 4kp60 resolution and source/sink has the same color format. Run below xmedia-ctl commands to set the resolution and format of the HDMI scaler node.

When HDMI Input Source is NVIDIA SHIELD

$ xmedia-ctl -d /dev/media0 -V "\"a0080000.v_proc_ss\":0  [fmt:RBG888_1X24/3840x2160 field:none]"
$ xmedia-ctl -d /dev/media0 -V "\"a0080000.v_proc_ss\":1  [fmt:VYYUYY8_1X24/3840x2160 field:none]"

NOTE: Make sure NVIDIA SHIELD is configured for 4kp resolution and RGB888 color format.

When HDMI Input Source is ABOX

$ xmedia-ctl -d /dev/media0 -V "\"a0080000.v_proc_ss\":0  [fmt:VYYUYY8_1X24/3840x2160 field:none]"
$ xmedia-ctl -d /dev/media0 -V "\"a0080000.v_proc_ss\":1  [fmt:VYYUYY8_1X24/3840x2160 field:none]"

NOTE: Make sure ABOX is configured for 4kp resolution and VYYUYY8 color format.

Follow the below steps to switch the HDMI-Rx resolution from 1080p60 to 4kp60.
- Check current HDMI Input Source Resolution (1080p60) by following the above-mentioned steps.
- Run vcu_gst_app for current HDMI resolution (1080p60) by executing the following command.

$ vcu_gst_app /media/card/config/input.cfg

Below configurations needs to be set in input.cfg for HDMI-1080p60.

Common Configuration    : START
Num Of Input            : 1
Output                  : HDMI
Out Type                : Display
Frame Rate              : 60
Exit

Input Configuration     : START
Input Num               : 1
Input Type              : hdmi
Raw                     : TRUE
Width                   : 1920
Height                  : 1080
Exit

- Change Resolution of HDMI Input Source from 1080p60 to 4kp60 by following the below steps.
  - Set the HDMI source resolution to 4kp60 (Home page → settings → display & Sound → Resolution → change to 4kp60).
  - Save the configuration to take place the change.
- Verify the desired HDMI Input Source Resolution (4kp60) by following the above-mentioned steps.

If HDMI Tx link-up issue is observed after Linux booting, use the following command:

$ modetest -D a0070000.v_mix -s 40:3840x2160-60@BG24 -w 36:"alpha":0

Run the following gst-launch-1.0 command to display raw HDMI video using the GStreamer pipeline.

$ gst-launch-1.0 v4l2src device=/dev/video0 io-mode=4 ! video/x-raw, width=3840, height=2160, format=NV12, framerate=60/1 ! queue ! kmssink bus-id="a0070000.v_mix"

Run the following gst-launch-1.0 command to display processed(capture → encode → decode → display) HDMI video using the GStreamer pipeline.

$ gst-launch-1.0 v4l2src device=/dev/video0 io-mode=4 ! video/x-raw, width=3840, height=2160, format=NV12, framerate=60/1 ! omxh265enc qp-mode=auto gop-mode=basic gop-length=60 b-frames=0 target-bitrate=60000 num-slices=8 control-rate=constant prefetch-buffer=true low-bandwidth=false filler-data=true cpb-size=1000 initial-delay=500 ! video/x-h265, profile=main, alignment=au ! h265parse ! omxh265dec internal-entropy-buffers=5 low-latency=0 ! queue max-size-bytes=0 ! fpsdisplaysink text-overlay=false video-sink="kmssink bus-id="a0070000.v_mix" sync=true" sync=true

Run the following gst-launch-1.0 command to record HDMI video using the GStreamer pipeline.

$ gst-launch-1.0 v4l2src device=/dev/video0 io-mode=4 ! video/x-raw, format=NV12,width=3840,height=2160,framerate=60/1 ! omxh265enc qp-mode=auto gop-mode=basic gop-length=60 b-frames=0 target-bitrate=60000 num-slices=8 control-rate=constant prefetch-buffer=true low-bandwidth=false filler-data=true cpb-size=1000 initial-delay=500 ! video/x-h265, profile=main, alignment=au ! h265parse ! queue ! mpegtsmux alignment=7 name=mux ! filesink location="/run/test.ts"

NOTE: File location should be USB-3.0 to avoid the read-write bandwidth issue.

Run the following gst-launch-1.0 command to play the recorded file using the GStreamer pipeline.

$ gst-launch-1.0 uridecodebin uri="file:///run/test.ts" ! queue max-size-bytes=0 ! fpsdisplaysink text-overlay=false video-sink="kmssink bus-id="a0070000.v_mix""