3GPP to PPM Converter

3GPP to PPM: One Frame, Stored Raw

A .3gpp file is the 3GPP file format — the ISO base media container specified in 3GPP TS 26.244 that phones used for video messaging and recording, usually holding H.263 or MPEG-4 video at a handset-era frame size. A .ppm is a Portable Pixmap from the Netpbm family: a two-line text header followed by raw red, green and blue samples with no compression whatsoever. This page pulls a frame out of the first and writes it as the second, which is what image-processing pipelines, scientific tooling and Netpbm command chains want when they need pixels with no decoder in the way.

How to Convert 3GPP to PPM

1. Upload Your 3GPP File: Drag and drop the .3gpp onto the page or click "+ Add Files". You can queue several clips and they all use the same frame-selection settings.
2. Choose Frame Selection: "Specific Frame" is preselected and grabs one still; type the moment into "Time (seconds)", where 0 is the opening frame and decimals such as 4.25 are accepted. Switch to "Multiple Screenshots" to pull a run of frames and set the "Capture Rate" — one image per second by default, from ten per second up to one every ten seconds.
3. Set the Bit Depth and Image Resolution: "Bit Depth" offers 8-bit (preselected), 16-bit and 1-bit — see the measured table below before changing it. "Image resolution" starts on "Keep original" and also offers Resolution Percentage, Preset Resolutions, Width, Height and Width x Height.
4. Convert and Download: Click "Convert". A single frame downloads as one .ppm; a run of screenshots produces one file per frame, which you can take individually or as a ZIP. No sign-up, no watermark.

What Bit Depth Actually Does

This control is not a compression setting, and the 1-bit option in particular does not do what its name suggests. Measured on a 176 x 144 frame pulled from a 3GPP clip:

Two results worth absorbing. 16-bit exactly doubles the file and adds nothing: a 3GPP video frame is 8-bit data, so the extra bits are padding, and only a downstream tool that specifically demands 16-bit samples has any use for it. 1-bit saves no space at all — it writes a maximum value of 1 per channel but still spends a whole byte on each sample, so the file stays the same size while the picture collapses to the eight colours you can make from one bit per channel. If you want a genuinely small file, reduce the resolution or use a compressed format instead.

A Tiny Phone Frame Becomes a Large File

PPM stores three bytes per pixel and compresses nothing, so its size is pure arithmetic — width times height times three, plus a short header. That turns even a handset-sized frame into something substantial:

That QCIF frame is about five times larger as a PPM than the lossless PNG the same pixels make. Nothing is wrong — that is the format working as designed. PPM exists so that a program can read an image in a dozen lines of code, not so that files stay small. If you want the same pixels in something a browser or a colleague can open, use 3GPP to PNG for a compact still — pick its "Highest" preset if you want the pixels kept exactly — or 3GPP to JPG for the smallest file.

How the Frame Is Extracted

Worth knowing because it determines the quality ceiling: the frame is decoded out of the 3GPP stream and written first as a lossless PNG, and that PNG is then converted to PPM. There is no intermediate lossy step, so the PPM holds exactly the pixels the video decoder produced — including whatever compression artefacts the phone's encoder baked in when the clip was recorded. Converting to an uncompressed format preserves those artefacts perfectly; it cannot remove them, and no bit depth or resolution setting will.

For "Multiple Screenshots", the capture rate is applied across the whole clip, so a six-second recording at one image per second yields six PPM files. Sub-second rates are available when you need several candidates around a fast moment — useful on 3GPP footage, where low frame rates and heavy compression mean neighbouring frames can differ a lot in sharpness.

Frequently Asked Questions

Nothing on my computer will open the .ppm file. Is it broken?

Almost certainly not. PPM is a Netpbm format aimed at programs rather than people: image-processing libraries, scientific tools, GIMP and ImageMagick read it happily, while most photo viewers and every mainstream browser do not. If you wanted a picture to look at or share rather than to feed into a pipeline, convert the same frame with 3GPP to PNG instead — far smaller, opens everywhere, and pixel-exact if you choose its "Highest" quality preset.

Which bit depth should I pick for a phone video frame?

8-bit, unless something downstream insists otherwise. The video decoder produces 8-bit samples, so 8-bit PPM captures everything present. We measured 16-bit producing a file exactly twice the size with no additional detail, and 1-bit producing a file the same size as 8-bit while reducing the picture to eight colours. There is no setting here that makes the file smaller while keeping the image intact.

Why is the extracted frame so small and blurry?

Because of what 3GPP recordings usually are. The format was built for early mobile video, where frames of 176 x 144 or 352 x 288 pixels at low bitrates were normal, and an uncompressed copy of a small, heavily compressed frame is still a small, heavily compressed frame. Converting to PPM records exactly what the decoder produced; it adds no detail. If the clip itself is higher resolution, check that "Image resolution" is on "Keep original" rather than a smaller preset.

How do I grab a frame from the middle of the clip?

Leave "Frame Selection" on "Specific Frame" and type the moment into "Time (seconds)". The field takes seconds with decimals, not minutes and seconds, so 1 minute 23 seconds is 83, not 1.23. The preselected value is 0, which is the opening frame — often a dark or half-drawn one on a phone recording, so a small non-zero value like 1.5 is usually a better first try.

Can I extract every frame of the clip?

Not literally every frame, but you can take a dense run of them. Switch to "Multiple Screenshots" and set the Capture Rate to its fastest value, ten images per second, and each second of the clip yields ten PPM files. Given that PPM is uncompressed, be careful what you ask for: at CIF resolution that is around 3 MB per second of video.

What is the difference between PPM, PGM and PBM?

They are the three core Netpbm formats and they differ only in how much colour they store. PBM holds one-bit black and white, PGM holds greyscale, and PPM holds full colour with three samples per pixel — this page writes PPM, so your frame keeps its colours. Each has a plain ASCII variant and a binary "raw" variant; the output here is the binary form, whose header starts with the magic number P6.

Does the PPM keep any of the video's metadata?

No, and PPM has almost nowhere to put it. The format's entire header is a magic number, the width, the height and the maximum sample value — there is no field for a timestamp, a camera model, a rotation flag or a colour profile. Anything the 3GPP file recorded about when and how the clip was shot stays in the video file.

Is PPM the same thing as BMP?

No, though both store uncompressed pixels. BMP is a Windows bitmap with a structured binary header that virtually every viewer opens, while PPM is a minimal text-headed format that mainly image tooling reads. BMP also has compressed variants and palette modes that PPM lacks. If you want an uncompressed frame that opens on any desktop, 3GPP to BMP is the more practical choice.

How are my files handled, and how long do you keep them?

Your clip is uploaded over an encrypted connection, decoded on our servers, and deleted automatically a few hours after conversion — no sign-up, no watermark, never shared or made public. 3GPP recordings are small, so these conversions are quick; the thing to watch is the size of what comes back, since a long run of uncompressed screenshots adds up faster than the source ever did.