Convert FLV to VOB — Free Online Tool
Convert FLV (Flash Video) files to VOB format for DVD-compatible playback, re-encoding the H.264 or FLV video stream to MPEG-2 and transcoding the AAC or MP3 audio to AC3 (Dolby Digital) — the codec pair required by the DVD-Video specification. This tool runs entirely in your browser with no file uploads required.
to
FFmpeg Command
Copy this command to run the same conversion locally with FFmpeg on your desktop. Download FFmpeg
Drop your FLV file here
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Free — no uploads, no signups. Your files never leave your browser.
Settings
Note: Browser-based encoding uses approximate quality targets. For precise CRF compression, copy the FFmpeg command above and run it on your desktop.
Estimated output:
Conversion Complete!
DownloadHow It Works
FLV files typically carry H.264 video and AAC or MP3 audio, neither of which are valid in a DVD-Video VOB container. This conversion performs a full re-encode: the video stream is decoded and re-encoded as MPEG-2 video (the mandatory codec for DVD-Video), and the audio is transcoded to AC3 (Dolby Digital) at 192k bitrate — the standard audio format on DVD discs. The output is wrapped in the VOB container with the required `-f vob` flag, producing a file structurally compatible with DVD authoring tools and standalone DVD players. Because both video and audio are fully re-encoded, this is a computationally intensive process and the output file will generally be larger than the source FLV.
What Each Flag Does
| Flag | What it does |
|---|---|
ffmpeg
|
Invokes the FFmpeg multimedia processing tool. This is the same underlying engine (compiled to WebAssembly) that powers this browser-based converter — copying this command lets you run the identical conversion locally on your desktop. |
-i input.flv
|
Specifies the input file as an FLV container, which FFmpeg will demux to extract the raw video (typically H.264 or Sorenson Spark) and audio (typically AAC or MP3) streams for re-encoding. |
-c:v mpeg2video
|
Re-encodes the video stream to MPEG-2, the codec mandated by the DVD-Video specification and the only video format VOB players and DVD authoring tools are guaranteed to accept. |
-c:a ac3
|
Transcodes the audio stream to AC3 (Dolby Digital), the primary audio format of DVD-Video. This replaces the FLV's AAC or MP3 audio with a format that DVD players and authoring software expect natively. |
-q:v 4
|
Sets the MPEG-2 video quality using a quantizer scale where 1 is the highest quality and 31 is the lowest. A value of 4 targets high visual fidelity suitable for DVD production, balancing quality against output file size. |
-b:a 192k
|
Sets the AC3 audio bitrate to 192 kilobits per second, a standard DVD audio bitrate that provides good stereo audio quality while remaining well within the DVD-Video specification's audio bitrate limits. |
-f vob
|
Forces the output container format to VOB (Video Object), ensuring the MPEG-2 video and AC3 audio are muxed into the correct DVD-Video container structure rather than FFmpeg guessing a format from the file extension alone. |
output.vob
|
The name of the output file. The .vob extension identifies this as a Video Object file ready for import into DVD authoring software to build a complete, disc-playable VIDEO_TS structure. |
Common Use Cases
- Archiving old Flash-era web video (downloaded FLV files from YouTube or similar pre-HTML5 platforms) onto DVD discs for long-term physical storage
- Preparing FLV recordings of live events, webinars, or conference sessions for DVD authoring software like DVD Flick or ImgBurn to burn playable discs
- Converting FLV-based screen recordings or training videos into VOB files for distribution on DVD to audiences without reliable internet access
- Recovering and re-purposing FLV files exported from old Flash-based video editors by converting them into a DVD-compatible format for client delivery
- Testing DVD authoring pipelines with MPEG-2/AC3 encoded content sourced from FLV files before committing to a full production burn
- Creating VOB files from FLV home videos originally captured via Flash-based webcam applications for inclusion in DVD memory collections
Frequently Asked Questions
FLV files encoded with H.264 are highly efficient — H.264 achieves excellent quality at relatively low bitrates. MPEG-2, the video codec required in VOB/DVD-Video files, is an older standard with lower compression efficiency, so the same visual quality demands significantly more data. Additionally, AC3 audio at 192k and the VOB container overhead contribute to the size increase. Expect output VOB files to be noticeably larger than the source FLV.
A VOB file alone is necessary but not sufficient for a standalone DVD player. DVD players require a full DVD-Video disc structure, including a VIDEO_TS folder with IFO and BUP index files alongside the VOB. This tool produces a valid MPEG-2/AC3 VOB file that you can import into DVD authoring software (such as DVD Flick, DVDStyler, or Encore) to generate the complete disc structure. The VOB itself won't be directly playable in a disc drive without that authoring step.
Yes, this conversion is lossy at both stages. The original FLV video (typically H.264) is decoded and re-encoded to MPEG-2, which introduces generation loss. The default `-q:v 4` setting targets high MPEG-2 quality, but MPEG-2 is inherently less efficient than H.264, so the result will not look identical to the source at the same bitrate. Similarly, audio is transcoded from AAC or MP3 to AC3, adding another lossy generation. Starting from a high-quality FLV source minimizes the perceptual impact.
For MPEG-2 video, `-q:v` sets the quantizer scale, where lower numbers mean higher quality and larger file sizes. The default of `4` is a high-quality setting appropriate for DVD production. Values of `1`–`3` push toward maximum quality with the largest files, while values above `8` start showing visible compression artifacts. In the FFmpeg command displayed on this page, you can copy it to your terminal and change `-q:v 4` to any integer between `1` and `31` to adjust the quality/size tradeoff for files over 1GB or for batch processing.
Yes. The displayed command processes a single file, but you can adapt it for batch conversion in a shell script. On Linux or macOS, use: `for f in *.flv; do ffmpeg -i "$f" -c:v mpeg2video -c:a ac3 -q:v 4 -b:a 192k -f vob "${f%.flv}.vob"; done`. On Windows PowerShell, loop over `Get-ChildItem *.flv` and invoke the command for each file. Batch processing in the terminal is especially practical for large collections of FLV files that exceed the browser tool's 1GB per-file limit.
No. FLV does not support subtitle streams or chapter markers, so there is nothing to carry over in that regard. General metadata (title, author, etc.) embedded in the FLV is also not transferred to the VOB output by this command, since VOB metadata handling differs significantly from FLV. If you need subtitles in your final DVD, they must be added as separate subtitle streams during the DVD authoring stage using dedicated authoring software after generating the VOB.
Technical Notes
VOB is bound by the DVD-Video specification, which mandates MPEG-2 video (typically at 720x480 for NTSC or 720x576 for PAL) and either AC3, LPCM, or MP2 audio. This command uses the defaults — MPEG-2 video and AC3 audio — which are the most universally supported combination. One important limitation: FFmpeg's `-f vob` flag forces the correct container type, but it does not automatically scale or constrain the video to DVD-legal resolutions or frame rates. If your source FLV has a non-standard resolution (e.g., 1280x720 or 1920x1080) or an unusual frame rate, the resulting VOB may be rejected by strict DVD authoring tools. For full DVD compliance, consider adding `-vf scale=720:480` (NTSC) or `-vf scale=720:576` (PAL) and `-r 29.97` or `-r 25` to the command. The MPEG-2 encoder in FFmpeg also supports `-b:v` for constant bitrate encoding, which may be preferable over `-q:v` when targeting DVD's maximum bitrate ceiling of ~9.8 Mbps. Multiple audio tracks are supported by the VOB format, but this command outputs only a single AC3 stream derived from the FLV's primary audio track.