Video doorbell/baby monitoring system solution

Video doorbells and baby monitoring systems are two seemingly unrelated solutions that offer the same functionality and have almost identical requirements in terms of transmitting video and audio between different locations. There are some subtle differences, but the main differences are in the connection and the power provided. Video doorbells can use wired or wireless connections, while baby monitoring systems are usually wireless only. If the video doorbell is integrated into the residential or building infrastructure, it can be provided with Ethernet power, 24V AC or any other offline voltage. At the heart of the system is a low-power embedded processor - DM3xx, OMAP-L13x or AM35xx. When implementing real-time video display (without video encoding), the total system power consumption is less than about 100mW. Even with full video encoding (needed for compression or storage), the total system power consumed is still less than 400mW.

The kernel subsystems include:

Processor - performs processing and synchronization of video, audio and controls the user interface.

Image Processing - The VPFE (Video Processing Front End) image processing functions provided in the previously mentioned processors can reduce the total system cost because advanced video optimization functions allow the use of cheaper sensor modules. The VPFE and display subsystem (also known as the Video Processing Back End - VPBE) can fully meet the LCD or TV display. The VPBE can also generate composite video output for analog TV and can display menus in real-time video for user control.

Video Encoding - To reduce packet transmission, these systems must have MPEG4 and H.264 video/audio compression capabilities, thereby consuming as little available bandwidth as possible. Video compression is also important for storing video to HDD or SD/MMC cards. In addition, H.264 provides smaller compressed video compared to MPEG4, while maintaining video quality after decompression.

Network Stack - Allows the user to transfer data over an Ethernet connection. The DM335 and DM355 both require an external Ethernet MAC and PHY, while all other processors have an onboard MAC.

Audio - Video Doorbell/Baby Monitoring System Two audio codecs; one for the capture side and the other for the display. The DM365 has a built-in mono audio codec, while all other processors require an external audio codec for audio input/output. The external audio codec can be connected to all embedded processors included in this block diagram through the McBSP port.

Memory - stores execution code, data/parameters, video and sound. DDR2 memory is most often used with video processors. For this we have specialized memory power devices that can provide all the required power rails for DDR, DDR2, DDR3 and DDR3L memory.

Power Conversion - AC/DC wall adapters are used in baby monitoring system applications, while readily available residential/building offline power supplies are used in video doorbells. Other power options include Power over Ethernet (PoE) which can use a wired Ethernet connection.

Optional Equipment – ​​Depending on the customer’s requirements, a remote display, laptop, digital video camera or single board computer with human machine interface (HMI) can be connected. A video doorbell that can display images remotely and store data on a hard drive can provide added functionality to the end user. Connecting the system to a computing platform can further improve the user experience.