What is a video capture card？
A video capture card is a device that converts video signals into digital signals and can be used to record, edit, convert, compress, store and play video content. According to different interfaces and performances, video capture cards can be roughly divided into two types: built-in video capture cards and external video capture cards.
Built-in video capture card
The built-in video capture card is an expansion card installed on the motherboard of the computer, usually connected with a PCI or PCI-E interface (similar to the installation of a discrete graphics card). The video signal can be obtained directly from video sources (such as camcorders, game consoles, DVD players, etc.), converted into digital signals, and saved to the computer hard disk. The built-in video capture card usually has high reading and writing speed and stability, and can support high-definition and high frame rate video recording and playback.
Advantages of built-in video capture card
High-performance transmission: Built-in video capture cards usually use high-quality hardware and dedicated circuits, which can achieve high-speed and stable video signal transmission, ensuring minimal data loss and delay.
Signal quality: The built-in capture card can usually maintain a high video signal quality, avoiding signal distortion, interference and other problems. It is suitable for applications that require accurate image and color performance, such as professional video editing, medical imaging and other fields.
Stability: The built-in capture card is installed inside the host, which reduces the risk of interference from external devices and cables, provides a more stable working environment, and reduces the possibility of accidental interruption.
Adaptability: Because it is built into the computer, the built-in capture card is usually easier to integrate with other hardware components to achieve more complex functions, such as multi-channel input, multi-screen switching, etc.
Space-saving: The built-in capture card does not require additional external space, and is more suitable for environments with limited space, such as laptops.
Disadvantages of built-in video capture card
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 flexibly move or share between different computers.
Higher cost: Since built-in capture cards require specialized hardware design and manufacture, their cost is usually high and may exceed some budgets.
Difficulty in maintenance: Once a built-in capture card fails, it may require more complicated repairs and longer downtime, compared to an external capture card that can be more easily maintained or replaced.
Inconvenient update: The technical update of built-in capture cards may be limited by the update cycle of computer hardware, and cannot be updated as flexibly as external devices.
External video capture card
An external video capture card is an independent device connected to a computer via USB or other high-speed read/write interfaces (such as the Thunderbolt interface), and is usually powered by an external power supply. It can acquire video signals from video sources (such as video cameras, game consoles, DVD players, etc.), convert them into digital signals, and transfer the collected audio and video signals to the hard disk of the computer through a USB cable. External video capture cards generally have good compatibility and flexibility, and can support video input and output of various types and formats.
Advantages of external video capture card
Easy to install: The external video capture card usually only needs to be connected to the computer through a cable, without hardware installation inside the host, so the installation is relatively simple and does not require professional knowledge.
Flexibility: The external capture card does not depend on specific computer hardware, and can be flexibly moved and shared between different computers. It is suitable for use in multiple scenarios, such as conference rooms, studios, etc.
Easy maintenance: Once the external acquisition card fails, usually only the device itself needs to be replaced without affecting other hardware of the computer, and the maintenance is more convenient.
Adaptability: External capture cards usually have a variety of input interfaces, which can be connected to different types of external devices, such as cameras, game consoles, etc., to provide greater adaptability.
Easy to update: The technical update of the external capture card is relatively independent, and the firmware can be upgraded more easily to meet new technical and functional requirements.
Disadvantages of external video capture card
Signal interference: The signal transmission of the external capture card may be subject to external interference, such as electromagnetic interference, signal attenuation, etc., which may affect the video quality and stability.
Signal delay: Since the signal needs to be transmitted through the connection line, the external acquisition card may introduce a certain signal delay, which may have limitations for applications that require real-time response.
External connection: Since the external capture card needs to be connected to the computer through a cable, the working environment may be messy, and the cable layout needs to be planned reasonably.
Restricted by the interface: The function 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 and high resolution may not be realized.
Inconvenient to carry: External capture cards require additional space and cables, which may increase the inconvenience of carrying for scenes with high mobility requirements.
In general, built-in video capture cards are suitable for scenarios that require high-speed high-definition, such as professional recording, editing, converting, compressing, storing and playing video content. External video capture cards are more suitable for scenarios that require portability and flexibility, such as live broadcast, teaching, conferences, monitoring, etc.