gwutilz/gwencoder/docs/reference/FLAG_REFERENCE.md

GWEncoder Flag Reference Guide

Complete reference for all command-line flags available in GWEncoder.

Encoding Modes

Flag	Description	Container	CRF	Preset	Audio
--fast	Daily driver, quick turnaround	MKV	28	10	Opus 64kbps/ch
--web	Streaming, Discord, web upload	WEBM	35	10	Opus 64kbps/ch
--tiny	Maximum compression	MP4	42	8	Opus 48kbps/ch
--hq	High quality archival	MKV	22	6	Opus 96kbps/ch
--slow	Best possible quality	MKV	18	4	Opus 128kbps/ch
--full	Full interactive mode	-	-	-	-

Codec Options

Flag	Description	Notes
--x264	Use H.264/x264 codec	Widely compatible
--nvhevc	Use NVIDIA NVENC HEVC	Requires NVIDIA GPU

AV1 Advanced Options

Flag	Values	Default	Description
--av1-preset	0-12	Mode default	Encoding speed (higher = faster)
--av1-crf	18-50	Mode default	Quality (lower = higher quality)
--av1-tune	0-2	0	Tune mode (0=VQ, 1=PSNR, 2=SSIM)
--av1-maxrate	kbps	0 (unlimited)	Maximum bitrate cap
--av1-disable-tf	-	false	Disable temporal filtering
--av1-disable-scd	-	false	Disable scene change detection
--av1-disable-aq	-	false	Disable adaptive quantization
--av1-10bit	-	false	Use 10-bit encoding
--av1-film-grain	0-50	-1 (disabled)	Film grain synthesis level

AV1 Preset Guide

Preset	Speed	Quality	Use Case
0-2	Very Slow	Highest	Archival, master copies
4-6	Slow	High	HQ mode, quality priority
8-10	Medium	Good	Fast mode, balanced
10-12	Fast	Lower	Quick encoding, speed priority

AV1 CRF Guide

CRF	Quality	File Size	Use Case
18-22	Very High	Large	Archival, master copies
24-28	High	Medium	General use, fast mode
30-35	Good	Small	Web distribution
38-42	Lower	Very Small	Maximum compression

Audio Options

Flag	Values	Default	Description
--aac	-	-	Force AAC audio codec
--opus	-	-	Force Opus audio codec
--abr	kbps	Mode default	Audio bitrate per channel
--audio-codec	aac, opus	auto	Target audio codec
--audio-quality	high, balanced, small	custom	Audio quality preset
--audio-preserve	-	false	Preserve original channels
--audio-stereo	-	false	Downmix to stereo
--audio-mono	-	false	Downmix to mono
--audio-bitrate-per-ch	kbps	-1 (auto)	Per-channel bitrate
--audio-stereo-bitrate	kbps	-1 (auto)	Stereo downmix bitrate
--audio-create-downmix	-	false	Create additional stereo downmix

Audio Quality Presets

Preset	AAC kbps/ch	Opus kbps/ch	Stereo kbps	Use Case
high	128	96	256	High quality archival
balanced	80	64	160	General use (default)
small	64	48	128	Maximum compression

Stream Options

Flag	Values	Default	Description
--reorder-streams	-	true	Reorder English streams first
--no-reorder-streams	-	false	Disable stream reordering
--convert-subs-srt	-	true	Convert subtitles to SRT
--no-convert-subs-srt	-	false	Disable subtitle conversion
--extract-subs	-	false	Extract subtitles to external files
--remove-subs-after-extract	-	false	Remove embedded subs after extraction
--lang-codes	codes	eng,en,...	Custom language codes (comma-separated)
--use-cc-extractor	-	false	Extract closed captions (requires ccextractor)
--embed-extracted-cc	-	false	Embed extracted CC as subtitle track

Video Options

Flag	Values	Default	Description
--maxrate	kbps	Mode default	Maximum video bitrate
--force-transcode	-	false	Force transcoding even if already in target codec

Information Options

Flag	Description
--help, -h	Show help information
--info	Show system information
--stats	Show encoding statistics

Flag Combinations

Common Combinations

Fast encoding with custom quality:

--fast --av1-preset 8 --av1-crf 30

Web distribution with bitrate cap:

--web --av1-maxrate 5000

High quality with audio options:

--hq --audio-quality high --audio-create-downmix

Maximum compression:

--tiny --audio-quality small

With subtitle extraction:

--fast --extract-subs --remove-subs-after-extract

With CC extraction:

--fast --use-cc-extractor --embed-extracted-cc

Flag Precedence

When multiple flags affect the same setting, the order of precedence is:

1. Explicit flags (e.g., --av1-preset 8) override mode defaults
2. Mode defaults apply when flags are not specified
3. Container-based defaults apply for codec selection

Notes

• All flags are optional except the encoding mode (--fast, --web, etc.)
• Flags can be combined in any order
• Some flags require values (e.g., --av1-preset 8)
• Boolean flags don't require values (e.g., --force-transcode)
• Default values are mode-dependent

Examples

See README.md for detailed usage examples.