DCTModes

Indicates the DCT compression mode for JPEG compression.

Remarks

The DCT Modes enumeration specifies the algorithm used for the Discrete Cosine Transform (DCT) step in JPEG compression. DCT is a mathematical process that converts image data into frequency components, enabling efficient compression.

Usage

• Select the appropriate DCT mode to balance image quality, compression speed, and compatibility.
• The default mode is typically 'Slow', which offers the best accuracy for most scenarios.
• 'Fast' and 'FloatingPoint' modes may be used for specialized performance or hardware requirements.

Configuration Guidance

• Use Default to rely on the encoder's recommended mode (usually 'Slow').
• Use Slow for maximum image fidelity, especially for archival or high-quality output.
• Use Fast for improved performance when minor quality loss is acceptable.
• Use FloatingPoint for environments where floating-point operations are preferred or required.

For more information, see the documentation for JPEG, Image Compression, and related image processing objects.

Can be one of the following values:

Name	Value		Description
Default	0	►	The default compression; usually 'Slow'. The Default mode uses the encoder's recommended DCT algorithm, which is typically the 'Slow' integer method. Usage Select when unsure which mode to use, or to follow best practices for most images.
Slow	1	►	Slow but accurate integer algorithm. The Slow mode uses a highly accurate integer-based DCT algorithm. Usage Recommended for most scenarios where image quality is a priority. May be slower than other modes, but produces the best results for photographic and continuous tone images.
Fast	2	►	Faster, less accurate integer method. The Fast mode uses a speed-optimized integer DCT algorithm. Usage Use when performance is more important than maximum image fidelity. May introduce minor artifacts or quality loss, but is suitable for preview images or rapid processing.
FloatingPoint	3	►	Floating-point method. The FloatingPoint mode uses a floating-point DCT algorithm. Usage Use in environments where floating-point operations are preferred or required. May offer different performance or quality characteristics depending on hardware and encoder implementation.

Used By

JPEG