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.
• Design has a negative slack of WNS around -50 ps . However it does not affect the functionality of the design in the long run also and will be fixed in next release.

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 AnchorPG252 2019.2PG252 2019.2PG252 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:
1,2,3 or 4

Output:
Select the video interface.
Options: HDMI

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 N^th input configuration.
Options: 1, 2, 3, or 4

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.
Options: file:///media/usb/abc.ts (for file path), udp://192.168.25.89:5004/ (for Network streaming, Here 192.168.25.89 is IP address and 5004 is port no)

Raw:
To tell the pipeline is processed or pass-through.
Options: False
Note: The raw use-case is not supported with this design as mixer is not connected to PS DDR.

Width:
The width of the live source.
Options: 4096, 3840, 1920

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

Format:
The format of input data.
Options: XV20

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

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

Encoder Num:
Starting N^th encoder configuration.
Options: 1, 2, 3 or 4

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

Profile:
Name of the profile.
Options: high for AVC and 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

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 N^th record configuration.
Options: 1, 2, 3 or 4

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 N^th streaming configuration.
Options: 1, 2, 3 or 4

Host IP:
The host to send the packets to
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

• HDMI source can be locked to any resolution. Run the below command for all media nodes to print media device topology where "mediaX" represents different media nodes. In the topology, log look for the “v_hdmi_rx_ss” string to identify the HDMI input source media node.

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

• To check the link status, resolution and video node of the HDMI input source, run below xmedia-ctl command where "mediaX" indicates media node for the HDMI input source.

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

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

root@zcu106_vcu_trd:~# xmedia-ctl -p -d /dev/media3 -----> media node for HDMI input source
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
                <- "a0040000.v_proc_ss":1 [ENABLED]

- entity 5: a0040000.v_proc_ss (2 pads, 2 links)
            type V4L2 subdev subtype Unknown flags 0
            device node name /dev/v4l-subdev3
        pad0: Sink
                [fmt:VYYUYY10_4X20/1280x720 field:none colorspace:srgb]
                <- "a0000000.v_hdmi_rx_ss":0 [ENABLED]
        pad1: Source
                [fmt:VYYUYY10_4X20/1920x1080 field:none colorspace:srgb]
                -> "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-subdev4
        pad0: Source
                [fmt:RBG888_1X24/3840x2160 field:none colorspace:srgb]
                [dv.caps:BT.656/1120 min:0x0@25000000 max:4096x2160@297000000 stds:CEA-861,DMT,CVT,GTF caps:progressive,reduced-blanking,custo
m]
                [dv.detect:BT.656/1120 3840x2160p60 (4400x2250) stds:CEA-861 flags:CE-video]  -----> Resolution and Frame-rate of HDMI Rx source
                -> "a0040000.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: