Free online USM to OGV converter

USM files are commonly game-video assets that ordinary media players and editors cannot open, while OGV is supported by open-source video tools and some web or Linux workflows. Converting usually requires extracting the USM streams first, then encoding the resulting video and audio as Theora and Vorbis.

What the USM format is

USM is a proprietary container used by CRI Middleware's Sofdec and CRI Movie systems for pre-rendered game cutscenes, menus, trailers, and other playback assets. You usually encounter it inside game installation directories or archives, often alongside files with names such as .usm, .cpk, or related CRI resources.

A USM can contain compressed video, audio, subtitles, interleaved streams, and sometimes encryption or game-specific protection. File extensions alone do not identify the exact codecs, so standard players and a stock FFmpeg build generally cannot decode every USM file directly.

What the OGV format is

OGV is an Ogg container normally holding Theora video and Vorbis audio. It is useful for open-source media applications, older HTML5 workflows, Linux software, and archival copies where patent-unencumbered codecs are preferred.

OGV is less widely supported than MP4 with H.264/AAC. If the destination application accepts MP4, WebM, or Matroska, those formats may provide better playback compatibility or compression.

How to actually convert USM to OGV

For a supported file, the simplest no-install option is the converter on 101convert.com: upload the USM file, choose OGV as the output format, start the conversion, and download the result. The service can only process USM variants for which its server has a compatible demuxer and decoder.

For local processing, use a USM-capable extractor such as VGMToolbox or a dedicated CRI USM extractor:

1. Make a backup of the original USM.
2. Open the file in the extractor and choose its USM or CRI Movie demultiplexing function.
3. Extract the contained video and audio streams. The output may be an MPEG-2 elementary video stream such as video.m2v and a decoded audio file such as audio.wav. Some extractors produce ADX or HCA audio instead; decode those with the appropriate CRI audio tool before encoding.
4. Install FFmpeg with Theora and Vorbis encoders, then run:

ffmpeg -i video.m2v -i audio.wav -map 0:v:0 -map 1:a:0 -c:v libtheora -q:v 7 -pix_fmt yuv420p -c:a libvorbis -q:a 5 -shortest output.ogv

Adjust -q:v from 1 to 10 for Theora quality, with higher values producing larger files. Adjust -q:a for Vorbis audio quality. If the extracted video already contains a playable audio stream, a single-input command may work:

ffmpeg -i extracted_video.mpg -c:v libtheora -q:v 7 -c:a libvorbis -q:a 5 output.ogv

Check the result with ffprobe output.ogv or a media player that supports Ogg Theora.

Quality and compatibility limitations

Re-encoding an already compressed game video reduces quality. Keep the original USM as the archival source, and use a higher Theora quality setting when fine detail or subtitles must remain readable.

If extraction produces separate streams with no timestamps, the converted file may lose synchronization. Use the extractor's original timing information where available; otherwise, inspect the output and correct delays with FFmpeg's -itsoffset option.

Encrypted or proprietary USM variants may require a game-specific key or decoder and cannot be converted by a generic tool. A USM containing only video also cannot produce meaningful audio; FFmpeg will create a video-only OGV unless a separate soundtrack is supplied.