x84_64 package broken on Ubuntu 20.04

[roger-]

Trying to install on Ubuntu 20 gives me:

❯ sudo dpkg -i v4l2rtspserver-0.3.7-Linux-x86_64-Release.deb      
dpkg: warning: parsing file '/var/lib/dpkg/tmp.ci/control' near line 1:
 'x86_64' is not a valid architecture name in 'Architecture' field: character '_' not allowed (only letters, digits and characters '-')
dpkg: error processing archive v4l2rtspserver-0.3.7-Linux-x86_64-Release.deb (--install):
 package architecture (x86_64) does not match system (amd64)
Errors were encountered while processing:
 v4l2rtspserver-0.3.7-Linux-x86_64-Release.deb

System details:

❯ cat /etc/os-release                                                                                          
NAME="Ubuntu"
VERSION="20.04.3 LTS (Focal Fossa)"
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME="Ubuntu 20.04.3 LTS"
VERSION_ID="20.04"
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
VERSION_CODENAME=focal
UBUNTU_CODENAME=focal

❯ uname -a                                                                                                    
Linux nuc 5.4.0-125-generic #141-Ubuntu SMP Wed Aug 10 13:42:03 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux