Pocket Tools
Three self-contained editors, each a single HTML file. Download one, double-click it, drop your files on the page. No install, no upload, no account, so your media never leaves the machine.
| Chapter | File | For |
|---|---|---|
| 1. Pocket Video Trimmer | Pocket_Video_Trimmer_vX.X.html |
Cutting, cropping, resizing, storyboards |
| 2. Pocket Video Joiner | Pocket_Video_Combiner_vX.X.html |
Joining clips, side-by-side comparisons, notes |
| 3. Pocket Image Editor | Pocket_Image_Editor_vX.X.html |
Batch conversion, captions, GIFs |
Also in this repo: Pocket_Auto_Splitter_(beta)_vX.X.html, still in beta.
Contents
1. Pocket Video Trimmer
A whole video trimmer in one file. Drop in a video and cut it up.
Trimming and cropping
Trim — scrub a filmstrip timeline, drag the in/out handles, step frame by frame, or type exact times. A slim bar under the timeline slides the whole selection without changing its length.
Multi-clip — queue several cuts from one video and export them all at once into a folder you choose.
Crop — a draggable box with ratio presets: 16:9, 9:16, 1:1, 4:5, 2:3, 21:9 or custom.
Resize and frame rate — percentage presets or exact pixels, at any frame rate.
Compression — one slider from smaller file to bigger file, with a live size estimate.
Extract audio only — pull the selection's audio out on its own as a WAV, without exporting any video.
Pictures and storyboards
Snapshot — save the frame you are parked on as a PNG.
Animated GIF — 256 colours per frame with dithering, so gradients don't band.
Auto storyboard — a grid of frames spread evenly across the selection, up to 10 × 10.
Manual storyboard — pick the exact frames yourself, with thumbnails, up to 25 of them.
Either sheet can number its cells 1, 2, 3… in the top-left corner, which is useful when you are referring to specific frames later.
Exact frame counts
Fixed frame rate hands frames to the encoder one at a time on a steady clock instead of letting the browser sample the canvas whenever it likes. The count corrects itself as it goes, so a busy machine doesn't drift.
H3-compliant frame count builds on that and rounds the total up to 17n + 5 frames — 5, 22, 39, 56, 73 and so on — taking the extra frames from real video after your out point. If there isn't enough video left, it steps down to the next valid count rather than inventing frames.
Worth knowing: the browser does the actual encoding, so treat the frame count as close rather than guaranteed. Check one output before trusting a whole batch.
Background work keeps storyboards and GIFs running while you are in another tab. Video export still pauses when the tab is hidden, because browsers stop decoding video for a background tab and you'd get one frozen frame with audio over the top.
Trimmer inputs and outputs
| Works | Usually won't |
|---|---|
| MP4 / H.264 · MOV · WebM · most MKV | AVI · exotic codecs |
Any resolution or aspect ratio, portrait or landscape.
| Format | |
|---|---|
| Video | MP4 (H.264 + AAC), WebM fallback |
| Pictures | PNG |
| Animation | GIF |
| Audio | WAV |
Files are named from the source, timestamp and settings, for example holiday_1m37s_1280x720_30fps.mp4.
Export runs in real time — a 30-second clip takes about 30 seconds — and it re-encodes, so the output isn't bit-identical to the source. The compression slider controls that trade-off. GIFs grow quickly; a smaller width at 10–15 fps usually works best.
2. Pocket Video Joiner
For putting clips together, or setting them next to each other to compare.
Joining clips end to end
Queue several videos and write them out as one continuous file, in the order you choose.
Side-by-side comparison
Play two videos next to each other in the same frame. Handy for before-and-after: an original against a re-encode, two different settings, or two takes of the same shot.
Notes on a video
Burn text onto a clip to mark what you are looking at — which settings produced it, what changed, what to look for. The note becomes part of the picture, so it survives being shared or re-uploaded.
3. Pocket Image Editor
Convert, label and resize images in batches, and edit GIFs.
Batch converting
Drop in a pile of images — or a whole folder — and convert them all in one pass.
Reads HEIC/HEIF, WebP, JFIF, AVIF, PNG, JPEG, GIF, BMP and TIFF.
Writes PNG, JPEG, WebP, AVIF or GIF. AVIF output depends on your browser: Chrome and Edge support it, Safari and Firefox may not.
Resize by longest side, exact width and height, scale, or a maximum file size that auto-tunes quality to hit it. Sideways iPhone photos are straightened automatically. Output names take a prefix, a suffix and a starting number, so a batch comes out in sequence.
HEIC decoding works out of the box. For a guaranteed-offline setup, drop heic2any.min.js in the same folder as the HTML file and it will be picked up automatically.
Captions, labels and memes
Add text layers to an image and drag them where you want.
Styles: WhatsApp-style bubble, meme text, a black box above, or a black box below. Each layer takes its own font, size, colour, background, padding, opacity, outline, position and rotation. Bubbles can be dragged, resized and rotated directly on the preview.
Emoji work in the text box — copy one from anywhere and paste it in. Whether it draws depends on the emoji your operating system has, so a very new one may come out as an empty box.
Working with GIFs
Load an existing GIF and change its playback speed, its looping, and its transparency with an adjustable alpha cutoff. Labelled images can be written straight out as a GIF, which is a quick way to turn a set of stills into a captioned animation.
Requirements
Chrome or Edge is the best bet. Firefox mostly works but falls back to WebM for video. No server, no dependencies, no build step, no sign-in.
Privacy
Everything happens inside the browser tab. The files make no network requests at all — you can open one, disconnect from the internet, and it will still work exactly the same.
by C_Nugget