3G2 to SWF Converter

3G2 to SWF: Getting a Phone Clip Into a Flash Timeline

The realistic reason to do this is that some Flash-era tool will not read your video. An older Adobe Animate or Flash Professional project, a piece of legacy courseware, a kiosk or signage player built in the 2000s — these ingest .swf and refuse everything newer. This page re-encodes a 3GPP2 phone recording into a Shockwave Flash movie so those tools will accept it.

Be clear-eyed about what you are making. Adobe ended Flash Player support on 31 December 2020 and started blocking Flash content on 12 January 2021; every major browser removed the plugin in early 2021. A .swf produced today opens in the Ruffle emulator, in a standalone Flash Player Projector, or inside the Flash authoring tool you are targeting — and nowhere else. If you simply want the clip to play, 3G2 to MP4 is the answer and you can stop reading.

How to Convert 3G2 to SWF

1. Upload Your 3G2 File: Drag the .3g2 onto the page or click "Add Files" to browse. .3gp files are accepted here as well, and several clips can be queued with the same settings.
2. Choose a Video Codec: Video Codec offers FLV — Sorenson Spark, which the page opens on — and MJPEG. Audio Codec has one entry, MP3, because that is the only audio the SWF container accepts.
3. Set File Compression, Video resolution and Trim (Optional): On the default FLV codec, File Compression opens on Quality Preset at Very High (Recommended), with Specific file size, Constant Bitrate, Variable Bitrate, Constant Quality and Constraint Quality alongside. Video resolution opens on Keep original. Trim offers Unchanged or a Time Range with a Start time and Duration.
4. Convert and Download: Click Convert and save the .swf. Files are uploaded over an encrypted connection, re-encoded on our servers, and deleted automatically after a few hours — no sign-up, no watermark.

Walk-through: Frame Size Is the Thing That Decides Whether This Works

3G2 recordings are small. The 3GPP2 file format exists because CDMA data rates were slow and handset screens were two inches across, so real files are usually 176 x 144 (QCIF), 320 x 240 (QVGA) or 352 x 288 (CIF), and 640 x 480 is about the ceiling. A Flash timeline built for a 1024 x 768 stage will show that clip as a postage stamp unless you plan for it.

Three ways to handle it, in order of how well they work:

• Leave Video resolution on Keep original and scale the movie inside your authoring tool. This is the right default. The SWF stays small, the timeline decides the display size, and you have not spent bits interpolating pixels the phone never recorded.
• Set an explicit frame with Width x Height if the consuming tool insists on a fixed stage size and cannot scale for you. Keep the aspect ratio of the source — 4:3 for almost every 3G2 — or the picture will stretch.
• Use Preset Resolutions to go bigger only if you have accepted the cost. A 176 x 144 frame blown up to 480p is a soft, blocky picture in a much larger file. It is legitimate when the tool demands a minimum size; it is not an improvement.

The other decision is the codec. FLV (Sorenson Spark) predicts each frame from its neighbours and keeps the whole rate-control panel available. MJPEG stores every frame as an independent JPEG: file size climbs sharply — over double on a like-for-like encode of the same short clip — and the option panel shrinks to Quality Preset and Constant Quality alone, with the bitrate modes and Specific file size disappearing. Pick MJPEG only if the tool you are feeding wants individual JPEG frames back out.

Finally, one thing you do not control: audio is resampled to 44,100 Hz. The SWF container permits only 44,100, 22,050 and 11,025 Hz, so the conversion pins the rate rather than let the muxer reject the job. That matters here more than on most sources, because 3G2 audio is often an 8 kHz speech codec — AMR-NB, EVRC or QCELP. Upsampling 8 kHz speech to 44.1 kHz makes the file bigger and does not make it clearer.

3G2 and SWF at a Glance

Codec Choice, Side by Side

Common Errors and How to Fix Them

• "The SWF will not play in my browser." Expected. Flash is blocked in every browser. Use Ruffle, a Flash Player Projector, or the authoring tool you are targeting.
• "The video is tiny in my Flash project." That is the source frame size, not a conversion fault. Scale it on the timeline, or set an explicit Width x Height before converting and accept the interpolation.
• "The picture is stretched." You forced a frame shape that does not match the source. Nearly every 3G2 is 4:3; use Width x Height values in that ratio, or Preset Resolutions, which sets the height and derives the width from the source.
• "The file grew enormously." You are on MJPEG. Switch Video Codec back to FLV.
• "There is no sound in the SWF." Some 3G2 files carry EVRC, QCELP or SMV speech audio that the decoder cannot handle, or carry no audio at all. Open the source in VLC first; if it is silent there, nothing on this page will change that.
• "The output looks worse than the phone clip." It is a second lossy generation on footage that was already compressed hard for a slow network. Raise the Quality Preset to limit the additional damage; nothing recovers the original detail.

When This Doesn't Work

If your destination has already dropped Flash — a browser, any current video editor, a web page, a modern LMS — this conversion produces a file that nothing there will open, no matter how you set it. Use 3G2 to MP4 for something that plays essentially everywhere, or 3G2 to FLV if the tool wants Flash Video specifically rather than a SWF movie. If you already have a .swf and need its content somewhere modern, SWF to MP4 goes the other way. Reserve this page for the case where a still-Flash-dependent pipeline genuinely requires SWF input.

Frequently Asked Questions

Why can I only choose MP3 for the audio?

Because the SWF container supports MP3 audio and nothing else — a format limitation rather than a policy choice, so the dropdown offers one entry instead of letting you build a file that fails to mux. The related constraint is on sample rate: SWF accepts 44,100, 22,050 and 11,025 Hz only, and the conversion pins the output at 44,100 Hz, because anything outside that set makes the muxer refuse the job outright.

My 3G2 audio was 8 kHz speech — does resampling it to 44.1 kHz improve it?

No. Upsampling adds sample points but no information: an AMR-NB, EVRC or QCELP track recorded at 8 kHz carries no content above 4 kHz, and resampling cannot invent any. What it does add is file size, since the MP3 encoder now has 44,100 samples per second to describe instead of 8,000. There is no control for this on the page because the container leaves no alternative.

Should I enlarge the video to fill my Flash stage?

Usually not at conversion time. A 176 x 144 or 320 x 240 phone frame scaled to 480p or 720p is soft and blocky in a much larger file, and Flash authoring tools can set the display size of a small movie on their own timeline, so enlarging the pixels here buys nothing. Set an explicit size here only when the consuming tool has a fixed stage it cannot adapt — and when you do, keep the 4:3 shape almost every 3G2 uses so the picture does not stretch.

FLV or MJPEG — which video codec should I pick?

FLV, unless you have a specific reason. Sorenson Spark predicts frames from their neighbours, which is what keeps a video file a sensible size, and it leaves every compression mode available. MJPEG stores each frame as a whole JPEG, so the file roughly doubles on a like-for-like encode, and the panel loses Specific file size and both bitrate modes — leaving Quality Preset and a 2-to-31 quantiser. MJPEG is worth it only when the downstream tool wants independent frames.

Will Ruffle play the SWF this page produces?

Ruffle is an actively maintained open-source Flash Player emulator, and it is the practical way to check your output on a modern machine. Its ActionScript support is the part still being completed; a movie like this one, which is a video stream with no scripting, is the simpler case. If Ruffle struggles, Adobe's standalone Flash Player Projector still runs .swf files locally, and so does the Flash authoring tool you are targeting.

Can I convert only part of the recording?

Yes. Switch Trim from Unchanged to Time Range and enter a Start time and a Duration, in seconds or as HH:MM:SS.sss. Only that window is decoded and re-encoded. Phone clips are short to begin with, so this is mostly useful for cutting a dead lead-in — the first second of a handset recording is often the camera still adjusting exposure.

Does the conversion keep the recording date from the phone?

No. A 3G2 stores creation and modification times in the container's movie header, and possibly a little more, but SWF has no equivalent metadata structure to carry them into. The output holds the picture and the audio and nothing else. Keep the original .3g2 alongside the SWF if the timestamp matters, because there is no way to recover it from the Flash file afterwards.

Why does my 3G2 fail to open in other software but work here?

Almost always the audio codec. CDMA handsets commonly recorded EVRC, EVRC-B or QCELP speech, and Windows, macOS and most editors have no decoder for those, so they reject the whole file rather than play the video without sound. This converter reads the file through an ffmpeg-based pipeline that handles the container and the common codecs, which is why it opens here. If yours uses one of the rarer CDMA speech codecs, the video converts but the audio track may not survive.

What happens to my files after the conversion?

Your clip is uploaded over an encrypted connection, decoded and re-encoded on our servers, and both the upload and the resulting .swf are deleted automatically after a few hours. Files are never shared or made public, and there is no sign-up, no watermark and no account required.