A video capture card is a device that converts video signals into digital signals. It can be used to record, edit, convert, compress, store and play video content. Video capture cards can be roughly divided into two types: built-in video capture cards and external video capture cards according to different interfaces and performance.
Built-in video capture card
Built-in video capture card is an expansion card installed on the computer motherboard, usually connected using a PCI or PCI-E interface (similar to the installation of a discrete graphics card). Video signals can be directly obtained from video sources (such as cameras, game consoles, DVD players, etc.), converted into digital signals, and saved to the computer hard disk. Built-in video capture cards usually have high read and write speeds and stability, and can support high-definition and high frame rate video recording and playback.
Advantages of built-in video capture cards
High-performance transmission: Built-in video capture cards usually use high-quality hardware and dedicated circuits to achieve high-speed and stable video signal transmission, ensuring minimal data loss and delay.
Signal quality: Built-in capture cards can usually maintain high video signal quality, avoiding signal distortion, interference and other problems. They are suitable for applications that require accurate image and color performance, such as professional video editing, medical imaging and other fields.
Stability: Built-in capture cards are installed inside the host, reducing the risk of interference from external devices and connecting cables, providing a more stable working environment, and reducing the possibility of unexpected interruptions.
Adaptability: Since they are built into the computer, built-in capture cards are usually easier to integrate with other hardware components to achieve more complex functions, such as multi-channel input, multi-screen switching, etc.
Space saving: Built-in capture cards do not require additional external space and are more suitable for environments with limited space, such as laptops.
Disadvantages of built-in video capture cards
Installation difficulty: Installing a built-in video capture card may require users to have certain hardware installation knowledge, and improper operation may cause damage to the host or other hardware components.
Limited flexibility: Compared with external video capture cards, built-in capture cards are less flexible and difficult to move or share flexibly between different computers.
Higher cost: Since built-in capture cards require special hardware design and manufacturing, their cost is usually higher and may exceed certain budget ranges.
Difficult maintenance: Once a built-in capture card fails, it may require more complex repairs and longer downtime. In contrast, an external capture card can be maintained or replaced more easily.
Inconvenient updates: The technical updates of built-in capture cards may be limited by the update cycle of computer hardware and cannot be updated as flexibly as external devices.
An external video capture card is an independent device connected to a computer via USB or other high-speed read and write interfaces (such as Thunderbolt interface), usually powered by an external power supply. It can obtain video signals from video sources (such as cameras, game consoles, DVD players, etc.) and convert them into digital signals, and transmit the captured audio and video signals to the computer hard disk via a USB cable. External video capture cards generally have good compatibility and flexibility, and can support video input and output of multiple types and formats.
Advantages of external video capture cards
Easy to install: External video capture cards usually only need to be connected to the computer via a cable, without the need for hardware installation inside the host, so the installation is relatively simple and does not require professional knowledge.
Flexibility: External capture cards do not rely on specific computer hardware and can be flexibly moved and shared between different computers, suitable for use in multiple scenarios, such as conference rooms, studios, etc.
Easy maintenance: Once an external capture card fails, it is usually only necessary to replace the device itself without affecting other computer hardware, making maintenance more convenient.
Adaptability: External capture cards usually have multiple input interfaces that can connect different types of external devices, such as cameras, game consoles, etc., providing greater adaptability.
Easy to update: The technical updates of external capture cards are relatively independent, and firmware upgrades can be performed more easily to adapt to new technical and functional requirements.
Disadvantages of external video capture cards
Signal interference: The signal transmission of external capture cards may be subject to external interference, such as electromagnetic interference, signal attenuation, etc., which may affect video quality and stability.
Signal delay: Since the signal needs to be transmitted through the connecting cable, the external capture card may introduce a certain signal delay, which may be limited for applications that require real-time response.
External connection: Since the external capture card needs to be connected to the computer through a connecting cable, it may cause a messy working environment, and the cable layout needs to be reasonably planned.
Limited by the interface: The functions and performance of the external capture card are limited by the interface and hardware design it provides, and some advanced functions such as multi-channel input, high resolution, etc. may not be realized.
Inconvenient to carry: The external capture card requires additional space and connecting cables, which may increase the inconvenience of carrying for scenes with high mobility requirements.
In general, the built-in video capture card is suitable for scenes that require high speed and high definition, such as professional recording, editing, conversion, compression, storage and playback of video content. External video capture cards are more suitable for scenes that require portability and flexibility, such as live broadcast, teaching, conference, monitoring, etc.
