Cliff Spark
New member
YUY2 and MJPEG are two different video compression formats commonly used in video capture devices and applications, but they serve different purposes and offer distinct advantages and trade-offs:
YUY2 (Uncompressed Format)
- Type: YUY2 is a raw video format where each pixel is represented by Y (luminance) and U, V (chrominance) components.
- Compression: It is uncompressed or lightly compressed (lossless), meaning it retains high image quality but requires more storage space and bandwidth.
- Color Space: YUV 4:2:2, meaning it uses chroma subsampling, which reduces color resolution slightly to save space.
- Quality: Very high, suitable for situations where preserving as much detail as possible is important.
- File Size: Large due to lack of compression.
- Use Case: Preferred for video editing or where image quality is paramount. Suitable for professional applications where post-processing will occur, such as video production or broadcasting.
MJPEG (Motion JPEG)
- Type: MJPEG stands for Motion JPEG, a format where each frame is compressed using the JPEG image format.
- Compression: Compressed (lossy), where each individual frame is stored as a JPEG image. It reduces the file size significantly but may lead to artifacts and loss of quality.
- Color Space: Typically uses 4:2:0 or 4:2:2 chroma subsampling, but it varies.
- Quality: Lower than YUY2 due to compression. However, it still provides decent quality for many purposes, especially with high enough bitrate.
- File Size: Smaller compared to YUY2, allowing more efficient storage and transmission.
- Use Case: Used in devices where bandwidth and storage are limited, such as security cameras, webcams, or streaming applications.
Key Differences:
- Quality: YUY2 offers higher quality since it's uncompressed or lossless, while MJPEG is compressed and can lose quality.
- File Size: MJPEG results in smaller files, while YUY2 files are much larger.
- Performance: MJPEG is easier on storage and network bandwidth but might put more strain on the CPU during decoding. YUY2 requires more bandwidth for capturing or streaming, which might be taxing on system resources.
Which to Use?
- YUY2: Ideal when you need high-quality video for editing, professional work, or when you have ample storage and bandwidth.
- MJPEG: Best for situations where you need smaller file sizes, such as online streaming, surveillance, or general-purpose video recording where extreme quality isn’t critical.