1: Connect the UHD signal source to the HDMI input of the video capture with one HDMI cable.
2: Connect the computer to the Type-c/usb port of the video capture with Type-c/usb cable.
3: Operation steps for USB video capture(OBS): Open the software → Choose sources of “Video capture Device”→Set the size of image→Choose “Studio Mode”(double window) →Choose “Start Recording”.

Operation Example as below

1. Add new sources, choose “ Video Capture Device ”/ “Audio Input Capture”

2.  Set the size of the image.

3. Choose “Studio Mode”(double window).

4. Click “ Start Recording”

Note:

Computer hardware configuration requirements

• CPU: PC i5-3400 or above ；NB i7-3537U 2.0GHZ or above
• Graphics card: PC NVIDIA GT630 or above；NC NVIDIA GT735M or above
• Run memory: 4G RAM

1. RGB Format

Definition

RGB is an uncompressed video format that represents images using the three primary colors: Red, Green, and Blue. Each color channel typically occupies 8 bits, resulting in a total of 24 bits per pixel. This format delivers high-quality visuals with accurate color reproduction.

Data Arrangement

In the RGB format, each pixel is represented by three consecutive bytes:

• R (Red)

• G (Green)

• B (Blue)

For example, a pixel might be stored as:

This structure ensures that each pixel has its own distinct color information.

Advantages

• Superior Image Quality: Being uncompressed, RGB offers lossless image quality, making it ideal for professional applications requiring precise color accuracy.

• Full Color Information: Each pixel retains complete color data, facilitating detailed post-processing and editing.

Disadvantages

• Large Data Size: RGB files are substantial, demanding significant storage space and bandwidth. For instance, a 1920x1080 resolution image at 24 bits per pixel results in approximately 6.22 MB per frame.

• High Bandwidth Requirements: Transmitting uncompressed RGB video necessitates high-speed interfaces like USB 3.0 or higher to handle the data flow efficiently.

2. YUY2 Format

Definition

YUY2 is a semi-compressed video format that employs chroma subsampling to reduce data size while maintaining reasonable image quality. It represents images in the YUV color space, which separates luminance (Y) from chrominance (U and V) components.

Data Arrangement

In YUY2, every four bytes represent two pixels:

Here:

• Y: Luminance component for each pixel.

• U and V: Chrominance components shared between two pixels.

This 4:2:2 chroma subsampling reduces color data by half compared to RGB, effectively decreasing the overall data size.

Advantages

• Reduced Data Size: By sharing chrominance information between pixels, YUY2 lowers data rates compared to RGB, easing storage and transmission demands.

• Balanced Quality: Offers a compromise between uncompressed quality and manageable file sizes, making it suitable for live streaming and real-time applications.

Disadvantages

• Color Accuracy Loss: Chroma subsampling can lead to slight color inaccuracies, particularly in areas with sharp color transitions.

• Moderate Bandwidth Requirements: While less demanding than RGB, YUY2 still requires a USB 3.0 interface for optimal performance, especially at higher resolutions and frame rates.

3. MJPEG Format

Definition

MJPEG (Motion JPEG) is a compressed video format where each frame is individually compressed as a JPEG image. This approach allows for significant reduction in data size while maintaining acceptable visual quality.

Data Arrangement

In MJPEG, the video stream consists of a sequence of JPEG-compressed frames:

Each frame is compressed independently, without reference to adjacent frames.

Advantages

• Efficient Compression: MJPEG significantly reduces file sizes, making it ideal for applications with limited storage or bandwidth.

• Compatibility: Widely supported across various platforms and software, ensuring broad compatibility.

Disadvantages

• Lossy Compression: The compression process can introduce artifacts and degrade image quality, particularly in scenes with rapid motion or complex textures.

• Variable Quality: Image quality depends on the compression ratio; higher compression leads to more noticeable quality loss.

4. Comparative Analysis

5. Recommendations

• Professional Video Production: If your work demands the highest image quality and you have the necessary storage and bandwidth, RGB is the preferred format.

• Live Streaming and General Use: For applications like live streaming where a balance between quality and data size is essential, YUY2 offers a suitable compromise.

• Limited Storage or Bandwidth: In situations where storage space or transmission bandwidth is constrained, such as web streaming or extended recordings, MJPEG provides a practical solution despite its lossy compression.

Understanding these formats enables you to make informed decisions when selecting an HDMI video capture card that aligns with your specific requirements, ensuring optimal performance and quality in your video capture endeavors.

1. The Role of Video Capture Cards

The primary function of a video capture card is to convert audio and video signals from devices such as game consoles or cameras into a digital format that computers can process. Unlike screen recording software alone, a capture card offers superior image quality, lower latency, and minimizes the load on your computer’s resources, making it an ideal tool for professional-grade recording and live streaming.

2. Types of Video Capture Cards

Video capture cards can be broadly classified based on their connection methods and installation types:

• Internal Capture Cards:
  Installed directly onto a desktop motherboard via a PCIe slot, these cards are known for their high stability and low latency. They are perfect for fixed workstations where performance is critical.

• External Capture Cards:
  Connected via USB ports, external capture cards are portable and ideal for laptops or scenarios where mobility is required. Their plug-and-play nature makes them user-friendly and flexible.

• Pass-Through Capture Cards:
  Featuring a pass-through (or loop-out) function, these cards allow you to output the video signal to a monitor in real time while capturing it. This is particularly useful for live monitoring during streaming or recording sessions.

3. Choosing the Right Video Capture Card

When shopping for a video capture card, consider the following factors to ensure you get the best performance for your needs:

• Interface Type:
  Common interfaces include USB 2.0, USB 3.0, and PCIe. Typically, USB 3.0 and PCIe interfaces support higher transfer speeds and better video quality, making them the preferred choice for high-demand applications.

• Resolution and Frame Rate:
  Depending on your needs, select a capture card that supports the highest resolution and frame rate required—whether it’s 1080p at 60 frames per second or 4K at 30 frames per second. Keep in mind that some cards may claim high-resolution support while their actual output capabilities are limited.

• Video Format Compatibility:
  For superior color reproduction and image quality, look for cards that support high-quality video formats like YUY2 or RGB.

• Pass-Through Capability:
  If you require real-time monitoring, opt for a capture card with a pass-through feature to enhance your workflow.

• Brand Reputation and After-Sales Service:
  Investing in a well-known brand with reliable customer support can ensure smooth operation and peace of mind during your projects.

4. A Step-by-Step Guide to Using a Video Capture Card with OBS Studio

Below is a basic tutorial on setting up a video capture card using OBS Studio:

1. Connect Your Device:
   Connect your video source (for example, a gaming console) to the capture card’s input via an HDMI cable. Then, connect the capture card to your computer using the appropriate interface (USB, PCIe, etc.).

2. Install Drivers and Software:
   Follow the manufacturer’s instructions to install the necessary drivers. Additionally, download and install OBS Studio or another compatible recording software.

3. Configure OBS Studio:

   • Launch OBS Studio and click the “+” button under the “Sources” section.

   • Select “Video Capture Device” from the list.

   • In the window that appears, choose your capture card from the device list.

   • Adjust the resolution, frame rate, and other settings based on the capabilities of your capture card and video source.

   • Once configured, you should see your video source displayed within OBS Studio.

4. Set Up Audio:
   Ensure that OBS Studio’s audio input and output settings are correctly configured to avoid issues like missing sound or echo.

5. Start Recording or Streaming:
   With all settings in place, you can now start recording your video content or go live.

5. Important Considerations

• Compatibility:
  Verify that the capture card is compatible with your computer’s operating system and hardware to prevent issues with device recognition or driver installation.

• Latency Issues:
  While high-quality capture cards generally offer low latency, it’s important to adjust settings and optimize performance based on your specific setup and requirements.

• Heat Dissipation and Stability:
  Continuous use of a capture card can generate significant heat. Choosing a product with effective cooling design will ensure better long-term stability and performance.

By understanding the functions, types, and selection criteria of video capture cards, as well as learning how to integrate them into your recording and streaming setup, you can elevate the quality of your video productions and enhance your overall creative workflow. Happy streaming and recording!

1. Product Description

Broadband powerline communication adaptor BPLC-LS700M is a broadband powerline carrier communication device with powerful functions and superior performance. It supports IP packets, RS485, RS232 serial port and other multi-protocol data on any two-wires, such as twisted pair, coaxial cable, DC wire, AC wire, parallel lines, elevator accompanying cables, etc. for high-speed long-distance transmission. The maximum physical layer rate can reach 240Mbps, and the longest point-to-point transmission distance can reach 500 meters. The relay version supports up to 10-level relays, and the longest transmission distance is 3-5KM.

BPLC-LS700M is a data transparent transmission device. It does self-route and self-organize network, and data is completely transparent. It can be configured to master and slave mode. The master and slave modes are configured using the master-slave switch on the back of the device. The device can support bus, star, tree, and mixed network topologies.

BPLC-LS700M integrates coupling circuit inside, high voltage isolation, anti-surge protection, suitable for carrier communication on 0-500V cable. The products have been widely used in various industries, including elevator network and elevator multimedia, railway communication monitoring system, mine monitoring system, inspection robot, wind energy new energy, intelligent charging pile, intelligent streetlamp, automated storage and retrieval system, traffic radar video monitoring and so on.

2. Technical Specification

3. Interfaces

It is all about how dark is the dark.

Ambient Light is the enemy of a projector.  Ambient light scattered by a screen enters our eye with the projector light reduces the contrast.  The key is to reduce the ambient light entering eye.

Fresnel Optical Structure 

The core element in Fresnel screens is the Fresnel lens. The Fresnel is made up from thousands of concentric lenses – each with its own unique profile. Barely visible to the naked eye, these lenses form a circular pattern from the screen center and outwards – like ripples in a pond.

With Fresnel screen, only light from the projector will be focused and ambient lights from both sides and top of the screen will be rejected.

The Fresnel screen can efficiently reject over 85% of the ambient light which makes the image vivid and bright under ambient light.

The core component of the Fresnel screen is a film that made of 8 layers: scratch resistant layer, color layer, diffusion layer, cylindrical lens layer, speckle suppression layer, Fresnel Lens layer, reflecting layer and black coating layer. 

Ultrashort Throw and Long Throw

By designing different Fresnel patterns, the screen can entertain ultrashort throw (laser TV) and long throw projector. For ultrashort throw, the film needs to have ultra flat supporting substrate, and this makes it expensive compared to long throw version as its more tolerant to the flatness of the supporting substrate. 

Tradeoff between gain and view angle 

By designing different Fresnel patterns, the screen can trade gain versus view angle. By focusing more lights into a narrow view angle, we achieve a high gain screen.

Normally, we have gain of 1.2 and view angle of 160 degree, and gain of 1.8 and view angle of 80 degree. Generally speaking, a large view angle is more expensive.

For better experience, a projector with more than 500 lumens is recommended. As the effect of the screen for a lower lumens will not be that obvious.

Form factors

The active component is the fresnel film. It can be installed on a string frame on a fabric like LinkSprite offers or attached on a rollable frame.

Experience the difference

This document analyzes the Mamba shield for Arduino with several experiments of powerlines communications over DC lines and AC lines. Principally, I’ve tried to guess the baud rate that this product can reach without transmission errors. INTRODUCTION

Power line communications technology is a way of carrying data on a conductor that can also be used for power transmission. You can use it to pass a control signal through the electrical wiring in a house for home automation. LinkSprite's Mamba shield gives your Arduino this ability. This Narrowband Powerline Communication shield can be controlled by your Arduino board using a simple SPI interface. From these places you can download the electric schematic, the codes and a step-by-step guide. The board needs to supply at least 1 Amp to work correctly. One of his inconvenient is that it needs a lot of caution if you use the board with high voltage. 

The main element of Mamba shield is the PLM-1 modem. That chip is the brain of the board. It is a fully digital data transceiver for powerline communications using Frequency-Shift Keying (FSK) and it is designed to be controlled from an external Central Processing Unit, most commonly a microcontroller (MCU). Implementing the PHY and MAC layers of the OSI model, the PLM-1 provides a way to efficiently modulate and demodulate data packets. It features collision detection, as well as automatic forward error correction and CRC-16 data integrity verification. For more information, you can read the AC-PLM User manual that it can be downloaded from [3&91;. After this brief introduction, I explain the tests with this Arduino Shield.

Projector can be installed on the table or from the ceiling. So there are two ways to install them.

On the table or stand:

Projector installed on ceiling:

The STL files can be downloaded at: 1 and 2

A1: App download and configuration method: Search "LinkSprite" in the AppStore(iOS) or PlayStore(Android) and download the app. 

Open the back cover of the doorbell, and there is a reset button inside. Press and hold it for 5 seconds. There will be a voice prompt “Waiting for configuration”. Tap + on the upper right corner of the app and scan the QR code on the doorbell label. Enter your home Wi-Fi password when prompt and point the QR code generated on the phone to the doorbell lens. When the doorbell prompt "Network configuration successful", the device will be added automatically into the App.

Q2: No sound from the host speaker when the doorbell button is pressed?

A2:First check whether the power supply of the speaker is normal, press the button on the indoor unit to check if there is sound from the speaker. 

No Sound: Check whether the power supply is connected properly. Replace the socket and test again. 

There is Sound: Which means the doorbell and the indoor unit are not paired, and it required to re-paired (Doorbell is already paired with the indoor unit by default when it leaves the factory) 

Pairing: If you need to re-pair, press Pairing Button until you hear a “Beep” sound. Then press doorbell button within 15sec and the indoor unit will ring. Which means pairing is successful. Note: The distance between the doorbell and the indoor unit must be more than 1 meter. 

Q3: Why does the doorbell always show offline status on the App?

A3：When someone rings the doorbell or someone stays at your door, it will go online. When the device is online, you can check the real-time picture outside the door through the mobile app. It is usually offline, and you cannot view the real-time picture outside the door when the doorbell are offline. 

Q4：How is the doorbell powered?

A4：Doorbell host should be connected to 24V AC or 12V DC power supply (Regardless of polarity), connected to the terminal on the circuit board behind the doorbell. Or modified to use 4 AA batteries according to the description on the last page of the manual. The indoor units should be plugged into power sockets for use. 

Q5：Failed to connect the doorbell to Wi-Fi?

Try to keep the doorbell within 30 meters of the Wi-Fi router, and there should be less than 2 walls in between. If the distance is less, it may be caused by the frequency of the router. The doorbell only supports 2.4GHz Wi-Fi. Please select 2.4GHz Wi-Fi for networking. If your Wi-Fi have the same name for both 2.4GHz and 5GHz, please change it to a different SSID for networking. 

Q6：Does the doorbell need to install a memory card?

A6：Our doorbell does not require you to buy a memory card. We provide 2 days of life time free alarm video cloud storage. Stored on the Amazon cloud service in the United States. 

Q7：What is the standby time of the doorbell when batteries are installed?

A7：The standby time is based on the frequency of your use and the standby time will vary. If there are less than 20 visitors per day with normal frequency of use, it will last for 1 month.