F4V to MTS Converter

Convert F4V to MTS: What This Tutorial Covers

This walks through turning an F4V — Adobe's MP4-based "Flash MP4" container — into an MTS file, the MPEG-2 transport stream that AVCHD camcorders record and that AVCHD-oriented editing projects expect. It is a narrow, specific job, so before the steps it is worth being blunt about one thing: if your goal is simply to play the clip, MTS is the wrong target and F4V to MP4 is the natural move, because F4V is already built on the same ISO base media container family as MP4. Choose MTS only when something downstream genuinely wants an AVCHD-style stream.

How to Convert F4V to MTS

1. Upload Your F4V File: Drag and drop your .f4v file onto the page, or click "+ Add Files" to browse. Several files queue and run with the same settings.
2. Confirm Video Codec and Audio Codec: Open the options panel. Video Codec is preselected on H.264 and Audio Codec on AAC. H.264 is the codec AVCHD is built on, so leave it alone; switch Audio Codec to AC3 if your editor or player wants the Dolby soundtrack AVCHD's own spec calls for.
3. Set Video Resolution or Trim (Optional): Video resolution starts on Keep original; switch to Preset Resolutions (1080p, 720p) or Width x Height to rescale, and use Trim with a Time Range to export only part of the clip.
4. Convert and Download: Click "Convert" and save your .mts file individually or as a ZIP. No sign-up, no watermark.

Walk-through: Choosing Codecs for an AVCHD-style Stream

The two dropdowns that actually change the outcome are Video Codec and Audio Codec, and the reason is that MTS is a transport stream — a carrier — not a codec. A .mts file can legally hold several different payloads, but AVCHD hardware and AVCHD-aware editors are only expecting one of them.

• Leave Video Codec on H.264. AVCHD's published format uses MPEG-4 AVC/H.264 (and MPEG-4 MVC/H.264 for stereoscopic 3D). The dropdown also offers MPEG-2, MPEG-4, DivX, Xvid, H.265 and MPEG-1, and the transport stream will happily carry those — but an AVCHD device will not recognise them.
• AAC is the default and is fine for editors and players. AVCHD's spec sheet lists Dolby Digital (AC-3) at 64–640 kbps, or linear PCM at 1.5 Mbps for two channels. Our MTS output defaults to AAC because that is what general-purpose players and NLEs read most reliably; AC3 is one click away when strict conformance matters.
• Leave File Compression on Quality Preset. It starts on Very High (Recommended), which targets a high-quality encode rather than a small file — the right call when the source is already compressed H.264. Specific file size, Constant Bitrate, Variable Bitrate, Constant Quality and Constraint Quality are the alternatives if you need to hit a number.
• Match resolution to the source. AVCHD tops out at 1920×1080, including 1080/60p and 1080/50p. Upscaling a 720p F4V to 1080p spends bitrate without adding detail.

F4V vs MTS at a Glance

Audio Codec Choices on This Page

Common Errors and How to Fix Them

• "The MTS won't import into my camcorder." A camera's AVCHD recording is a whole volume — nested folders plus playlist and clip-information files the camera writes and reads — not a single loose .mts. A converted stream is a valid MTS for editors and players, but dropping it onto a card does not rebuild that volume.
• "The file is much bigger than the F4V." Expected. F4V was tuned for web delivery; an AVCHD-style transport stream carries more container overhead and is usually encoded at higher bitrates. Lower the Quality Preset, or set a Specific file size, if it matters.
• "My editor reports no audio." Some AVCHD-oriented tools only look for Dolby Digital. Re-run with Audio Codec set to AC3.
• "The picture combs or judders." AVCHD historically records interlaced fields (60i/50i), and some players guess the field order wrong on a progressive source. Play it in a deinterlacing player such as VLC before assuming the conversion failed.
• "Nothing imports at all." Check the F4V opens in VLC first. A partially downloaded or DRM-protected Flash file will fail to decode, and no container change fixes that.

When This Doesn't Work

If the F4V is DRM-protected or truncated, it will not decode and no target format will recover it. And if your real aim is editing, archiving or sharing rather than feeding an AVCHD-specific pipeline, MTS makes the file larger and more awkward for no benefit — F4V to MP4 keeps it small and broadly playable, and MTS to MP4 is the way back out if you regret the detour. To go the other direction entirely, there is a reverse tool at MTS to F4V.

Frequently Asked Questions

Why convert a Flash-era F4V to MTS at all?

It is a niche move with one good reason: something downstream — an AVCHD editing project, an ingest folder, a device or a piece of software — insists on .mts. F4V itself is orphaned. Adobe stopped supporting Flash Player on 31 December 2020 and began blocking Flash content from running on 12 January 2021, so these files should be moved to a maintained format while converters still read them. For most people that destination is MP4, not MTS; pick MTS only when the AVCHD ecosystem is the actual target.

Will I lose quality going from F4V to MTS?

A little, because this is a re-encode. F4V holds H.264 inside an ISO base media container; MTS uses an MPEG-2 transport stream, a different wrapper entirely. Our pipeline decodes and re-encodes rather than lifting the stream over intact — there is no stream-copy path here — so some generation loss is unavoidable. Keep Quality Preset on Very High (Recommended) and leave Video resolution on Keep original and the difference is hard to see, because you are re-encoding already-compressed H.264 at a high quality target.

Should I choose AAC or AC3 for the audio?

Start with AAC, which is what this page selects by default and what general-purpose editors and players handle most reliably. Switch to AC3 if a device or program that follows the AVCHD spec rejects the file or plays it silently — Dolby Digital at 64–640 kbps is one of the two audio codecs AVCHD itself defines, the other being linear PCM. Both survive the transport stream fine; it is the receiving software that decides which one it will accept.

Can I put the converted MTS back onto my camcorder's SD card?

Usually not. AVCHD is a recording format for specific media — SD cards, Memory Stick, built-in camera storage and 8 cm DVD — and a camera reads its own volume structure, complete with playlist and clip-information files, rather than a loose stream. The output here is a valid MTS for editors and media players, but it is not a card-ready AVCHD recording. Treat it as an editing and playback file.

Why is my MTS so much larger than the F4V?

Two reasons stack up. First, an MPEG-2 transport stream is packetised into fixed-size packets with repeated program information, which costs more overhead than the ISO base media layout F4V uses. Second, the default here is a quality target, not a size target, so the encoder spends whatever bitrate it needs to hold detail. If size matters, switch File Compression from Quality Preset to Specific file size and name a number, or step the preset down from Very High.

Would MP4 be the better target than MTS?

For most goals, yes. F4V is already based on the MP4 container family, so F4V to MP4 is the closer, smaller, far more portable conversion — MP4 plays in Chrome, Firefox, Edge and Safari and on essentially every phone and TV, while neither F4V nor MTS plays natively in any browser. MTS earns its place only when an AVCHD editing project or a specific device demands it.

What resolution should I use for AVCHD compatibility?

Stay at or below 1920×1080. AVCHD's published format tops out there, with 1080/60p and 1080/50p among the modes it lists, so a 4K output in an .mts wrapper is outside what AVCHD hardware expects even though the transport stream can carry it. Video resolution starts on Keep original, which is right if your F4V is already 1080p or smaller. Use Preset Resolutions to step down, and resist upscaling — it adds bitrate, not detail.

How are my files handled, and how long are they kept?

Your F4V is uploaded over an encrypted connection, processed on our servers, and deleted automatically after a few hours. There is no sign-up, no watermark on the output, and your files are never shared or made public. On a large batch the practical constraint is upload time rather than a per-file cap, so if you only need one section, setting a Trim start and duration before converting is the fastest route.