With live stream or playback video generated by the eDVR board set to MPEG4, the Client plays frames out of order resulting in stuttering video.
Description:
The video stutters — playing new frames, then older frames, creating a very jerky display effect. The video clip was MPEG4 with B frames. This seems to be caused by the specification of “low delay” with ffmpeg. With H.264 they still detect if B frame re-ordering is required and will delay the video when necessary. They don’t seem to do this with MPEG4 so we can’t specify that option with it. This is a pre-existing issue for Linux x64 and macOS x64 because these always used ffmpeg to decode MPEG4. However, this issue was new to Windows because IPP was used to decode MPEG4 prior to version 19.06.
Adding Western Digital (WD) Gold and Ultrastar Enterprise class SATA hard disk drives to server versions prior to 19.06 will result in the drives being incorrectly reported with a temperature “Threshold Exceeded” status. Although verified with these two particular series of drives, the issue may apply to others as well.
Root Cause
The software tools for extracting the hard disk drive S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology) data varies by connection scheme (RAID controller vs direct to motherboard), RAID controller manufacturer (3ware vs LSI), and hard disk drive model series (Gold vs Ultrastar). The temperature data may need to be adjusted to arrive at at the actual temperature. The server <hwmconfig.xml> file contains S.M.A.R.T. attribute processing rules for drives that require attribute processing in order to display a reasonable temperature and determine the threshold range. This file has been traditionally limited to periodic updates as new hard disk drive models are introduced. In server version 19.06+, the drive detection S.M.A.R.T. configuration algorithm has been optimized to eliminate specific hard disk drive model number dependencies.
Workaround
While manually customizing the existing <hwmconfig.xml> file to include the particular hard disk drive model number may serve as a workaround, it is ONLY recommended for those systems that CANNOT be upgraded to server version 19.06+. It is preferable to upgrade the server software because the drive detection S.M.A.R.T. configuration algorithm has been optimized to eliminate hard disk drive model number dependencies.
Location of <hwmconfig.xml>:
On Microsoft Windows Servers : C:\Program Files\exacqVision\Server
On Ubuntu Linux Servers: /usr/local/exacq/server
Configuration Storage page Hardware tab before modification of <hwmconfig.xml> file.Configuration Storage page Hardware tab after modification of <hwmconfig.xml> file.
