Engineering and technology notes

ESP8266 WIFI Camera | Arduino Based Camera

Jovan Stosic July 25, 2017

ArduCAM now released a world smallest low cost ESP8266 WIFI IoT camera kit based on ArduCAM-Mini-2MP-V2 and ArduCAM-ESP8266-Nano module. User can implement a 2MP WIFI camera using HTTP or Websocket protocol on ESP8266, and the camera can be acted as an AP and mobile phone/PC can connect to the camera directly or acted as a Station which connected to the home router. The kit can capture 2MP full resolution JPEG still image, even stream low resolution at fairly frame rate video over network or directly save to local SD/TF card. The kit is suitable for portable application, it can be powered from micro-USB or using battery and has build in lithium battery charging circuits. The kit can also be used separately, it is almost identical to standard alone ArduCAM-Mini-2MP camera and ESP8266-12F module. Continue reading “World Smallest ESP8266 WIFI Camera” »

Source: ESP8266 WIFI Camera | Arduino Based Camera

Overtone

Jovan Stosic July 17, 2017

An overtone is any frequency greater than the fundamental frequency of a sound. Using the model of Fourier analysis, the fundamental and the overtones together are called partials. Harmonics, or more precisely, harmonic partials, are partials whose frequencies are integer multiples of the fundamental (including the fundamental which is 1 times itself). These overlapping terms are variously used when discussing the acoustic behavior of musical instruments.[1] (See etymology below.) The model of Fourier analysis provides for the inclusion of inharmonic partials, which are partials whose frequencies are not whole-number ratios of the fundamental (such as 1.1 or 2.14179).

Source: Overtone – Wikipedia

No video in IE activex with DVR – CCTV Forum

Jovan Stosic July 17, 2017

Had the same problem displaying video on a PC that had 2 or more monitors attached. If I were to disable one of the monitors, the video would instantly come up. If it has a problem on a pc with dual monitors, then this leads me to believe it will probably have problems with various video cards out there.I strongly advise you to get rid of this hunk of junk. I had NOTHING but problems with it…

Source: No video in IE activex with DVR – CCTV Forum

r3580 cannot connect with mpd 0.18.1 – “Failed to send command to “Default” (localhost:6,600) – not connected” · Issue #325 · CDrummond/cantata

Jovan Stosic July 14, 2017 
From the log file, it looks as if "listallinfo" failed. Cantata uses this 
command to get the music listing from mpd. Do you have this disabled in your 
MPD setup? (not sure if this can be done though!)

What happens if you run the following from a commandline:

1. Connect to to MPD via telnet:
    telnet localhost 6600

2. In the telnet window, type
    listallinfo

3. To quit telnet; press 'Ctrl' and  ']' together - then type 'quit' at the 
'telnet>' prompt.

Did the listallinfo work above?

-------------------

You mention KWallet - is your MPD password protected? With the trunk version of 
Cantata, you can disable the KWallet usage (pass -DENABLE_KWALLET=OFF to cmake)

 

Source: r3580 cannot connect with mpd 0.18.1 – “Failed to send command to “Default” (localhost:6,600) – not connected” · Issue #325 · CDrummond/cantata