Trim OGV

How to Trim OGV Videos Online

1. Upload Your OGV File: Drag and drop or click "+ Add Files" to load your Ogg Theora video. Multiple files can be queued and trimmed in one batch.
2. Set the Trim Range: Open the Trim panel, pick "Time Range," and enter Start (HH:MM:SS.ms) and Duration. The original is preserved end-to-end so frame-accurate cuts on a long source are fine.
3. Tune Compression and Resolution (Optional): Under File Compression pick Quality Preset (Highest to Lowest), Target file size (%), Specific file size, Constant Bitrate, Variable Bitrate, Constant Quality (CRF), or Constraint Quality. Under Video Resolution keep original, choose a preset (1080p, 720p, 480p, 360p, 240p, 144p), or enter exact width and height.
4. Trim and Download: Click "Trim." Files process in your browser session — no sign-up, no watermark, no upload to a third-party server.

Why Trim OGV Files?

OGV is the file extension for video stored in an Ogg container with the Theora video codec, usually paired with Vorbis or Opus audio. The format is fully open and royalty-free, developed by the Xiph.Org Foundation, and is one of the three formats Wikimedia Commons accepts for video uploads (alongside WebM and MPEG-1/2). Theora was first specified in 2004 with libtheora 1.0 stable in November 2008, and although browser support has narrowed in recent years it remains the standard hand-off format for several open-source and educational workflows.

• Wikimedia Commons uploads — Commons accepts OGV, WebM, and MPEG-1/2 only and rejects patent-encumbered MP4/MOV. Trimming locally before upload keeps you under the 5 GB single-file cap and avoids re-encoding through video2commons.
• Creative Commons / educational clips — pulling a 90-second teaching segment out of a 30-minute lecture recording is the most common reason editors trim OGV files for university OER repositories and Wikiversity.
• Linux / open-source project demos — bug reports, screencasts, and release notes in projects that mandate royalty-free media (Debian, FSF, Wikimedia) keep the source as OGV rather than re-encoding to H.264.
• Archival sources — older Internet Archive and Xiph reference clips are distributed as .ogv; trimming preserves the codec for downstream editors who want a lossless re-encode path.
• Avoiding patent-encumbered output — H.264/H.265 require AVC/HEVC patent licenses for distribution at scale; trimming OGV in OGV avoids that licensing surface entirely.
• Smaller share clips — slicing a 5-minute Theora source down to a 30-second highlight cuts file size proportionally and keeps it within typical messaging or LMS attachment caps.

OGV vs WebM vs MP4 — Format Comparison

Property	OGV (Ogg Theora)	WebM (VP9/AV1)	MP4 (H.264/H.265)
Container	Ogg	WebM (Matroska subset)	ISO BMFF
Video codec	Theora	VP8, VP9, AV1	H.264, H.265, AV1
Audio codec	Vorbis, Opus, FLAC	Vorbis, Opus	AAC, AC3, MP3
License	Royalty-free	Royalty-free	Patent-encumbered (AVC/HEVC)
Chrome playback	Removed in v123 (Mar 2024)	Supported	Supported
Firefox playback	Disabled by default since v126	Supported	Supported
Safari playback	Never supported	VP9 since 14.1, AV1 partial	Supported
Wikimedia Commons	Accepted	Accepted (preferred: VP9)	Rejected
Typical 1080p bitrate	2.5-5 Mbps	1.5-3 Mbps (VP9)	4-8 Mbps (H.264)
Origin year	2004 (libtheora 1.0: 2008)	2010	2003 (H.264) / 2013 (H.265)

Quality Preset and CRF Quick Guide for Theora

Theora's quality scale runs 0-10 (passed to the encoder as -q), where higher means better. The xconvert presets and the Constant Quality slider map roughly as follows:

Setting	Theora -q	Typical 1080p bitrate	Use case
Highest	9-10	5-8 Mbps	Master / archive copy
Very High	7-8	3-5 Mbps	Wikimedia upload, screencasts
High	6	2-3 Mbps	General web embedding
Medium	4-5	1.2-2 Mbps	LMS / email attachment
Low	2-3	0.6-1.2 Mbps	Quick preview share
Lowest	0-1	0.3-0.6 Mbps	Smallest possible at watchable quality

For a target file size, use Target file size (%) or Specific file size and let the encoder pick the bitrate; for predictable visual quality across a project, use Constant Quality (CRF) at a fixed value.

Frequently Asked Questions

Will my trimmed OGV still play in Chrome and Firefox in 2026?

Chrome removed Theora decoding in version 123 (stable in March 2024) and Firefox disabled it by default starting in version 126. The file itself is unchanged, but for in-browser playback most users will need to convert the trimmed clip to WebM or MP4. If your destination is Wikimedia Commons or a desktop player like VLC or mpv, OGV still plays fine.

Should I keep the output as OGV or re-encode to WebM/MP4 after trimming?

Keep OGV when the destination requires royalty-free media — Wikimedia Commons, Wikipedia articles, Debian/FSF projects, and Creative Commons archives explicitly disallow patent-encumbered codecs. For YouTube, social, embedded web video, or Apple devices, convert OGV to MP4 for universal playback or OGV to WebM to stay royalty-free with a modern codec (VP9/AV1).

Can I trim without re-encoding so quality is preserved?

xconvert's Trim re-encodes by default so you can also adjust resolution and bitrate in the same pass. If you need a true bit-exact cut with zero quality loss, the canonical CLI tool is oggCut (part of liboggz / oggvideotools); it does keyframe-aligned splits without touching the codec. The trade-off is that the cut points snap to the nearest Theora keyframe rather than landing on an exact frame.

Why is my trimmed OGV file larger than I expected?

A few common causes: (1) the input was already at a low bitrate and the default Quality Preset is encoding at higher quality than the source, (2) Theora is less efficient than VP9 or H.264 at the same visual quality — a 2-minute 1080p Theora clip can run 30-60 MB where the WebM equivalent is 15-30 MB. Drop the preset to Medium or Low, or pick Target file size (%) and aim for 50-70% of the source.

Will Vorbis or Opus audio be preserved when I trim?

Yes. The Trim operation keeps the audio stream intact and re-multiplexes it into the output Ogg container. If you also change the resolution or video codec settings the audio is typically passed through unchanged unless you explicitly select a new audio codec.

What's the largest OGV file I can trim?

There is no fixed file-size cap on xconvert beyond what your browser session can hold in memory. For multi-gigabyte sources keep the source tab as the only heavy tab and use a Chromium-based browser; processing happens in the browser session rather than uploading to a server. For Wikimedia Commons, note that Commons itself caps single-file uploads at 5 GB.

How do I make a trimmed OGV smaller without losing too much quality?

Two effective levers: drop resolution one tier (1080p to 720p typically halves file size) and pick Constant Quality at -q 5-6 instead of the Highest preset. If you only need the cut for sharing, compressing the trimmed file with target file size (%) gives a predictable output size while letting the encoder pick the bitrate.

Can I trim multiple OGV files in one batch?

Yes. Add multiple files in step 1 and the same trim range, compression, and resolution settings apply to all of them. Each output is delivered as an individual .ogv file (no archive bundling). For different trim ranges per file, run them as separate batches.

Does trimming work for .ogg files that are video, or only files with the .ogv extension?

The .ogg extension predates .ogv and was originally used for any Ogg-container file (audio or video). If your file is video-in-Ogg saved with the .ogg extension, rename it to .ogv before uploading or convert it first — the xconvert pipeline keys off the extension when picking the right decoder.