Watch your best moments again – frame by frame, in buttery-smooth slow motion.
The video player built for action cam footage.
You nailed the jump – or almost did. What happened in that split second between take-off and landing? Replayer lets you find out.
- 🎥 Analyse your action cam footage. Open a whole session folder and flip through your clips in a second. GoPro chapters stay together.
- 🪞 Film yourself, then study your technique. Set up the camera, do your run and watch every movement in detail – in slow motion or one frame at a time.
- ⏱️ Improve your timing. Line up several attempts side by side and see exactly where one take-off was better than the other.
- ✂️ No remote? No problem. Keep the camera rolling for all your runs, then split the recording into one clip per attempt.
Put your camera next to the kicker and do five runs. Back home, open the folder, select all five clips and line them up at the take-off. Now play them together in slow motion: Where did you pump? When did you pop? How high was the front wheel? Measure the height and your speed at the lip, and draw the line you want to take next time. Differences you never notice at full speed become obvious.
The same works for skiing, skateboarding, climbing, running, golf, tennis – anything you can film.
Replayer uses your graphics card to decode and display video. Even 4K at 120 fps or 240 fps slow-motion footage plays smoothly – no stuttering, no waiting.
Switching clips, scrubbing, stepping frame by frame: everything reacts instantly. Each clip remembers where you left it, so you can jump back and forth between takes without losing your spot.
Play back up to 20x slower, step forward and backward one frame at a time and loop the interesting part as often as you like.
Select up to six clips and watch them side by side. Align them at the key moment, then play, pause and step them all in sync.
No camera remote? Just keep recording while you do jump after jump. Right-click the recording and choose Split Clip...: set a marker between the runs, skip the walk back up, and every run becomes a clip of its own – ready to compare side by side. Or let Suggest Markers find the jumps for you by detecting the motion in the picture. Your video files stay untouched.
Right-click a clip to give it a color – green for the jump that went really well, red for the one that almost ended badly. Clips that show nothing of interest can be hidden, so they don't clutter the list; the eye button next to the folder name brings them back.
Zoom in up to 8x with the mouse wheel and drag to look at the details – your hands, your feet, your line.
Mark what matters right on the video: lines, arrows, circles and freehand strokes in six colours and any line width. Point out your body position, the ideal line or the spot where you should have popped. Every clip keeps its own drawings, and they stay in place when you zoom and pan. Made a mistake? Undo, redo or clear with one click.
Want to share it? See Export your best moments below.
Draw a reference line along something of known length – a bike wheel, a ramp, a measuring tape – and enter its real length. From then on, every measuring line shows its real length – in metres, centimetres, feet, inches, whatever unit you entered. How high did you get? How far did you jump? Now you know.
Click a point – say, your front tyre – and set marker A. Step forward a few frames, click the same point again and set marker B. Replayer turns the distance and the time between the two frames into your speed, in km/h or mph. Find out how fast you really were on the take-off.
Press Ctrl+E to save a frame as PNG or JPEG, or a part of the clip as an MP4 video or a GIF animation. Set the start and end markers right in the export dialog, slow it down up to 20x, scale it down for sharing, and choose whether your drawings, measurements and a time stamp are burnt in. Ready for your group chat in seconds.
A clean dark theme that keeps the focus on your video, with large, easy-to-grab controls. Pick the accent colour you like best.
Runs on Windows and Linux. On Windows, just unzip and start – no installation needed. On Linux, there is a single AppImage, and Arch users get it from the AUR.
No ads. No telemetry. No subscription. No account. Replayer is free and open source under the GNU GPL v3 – forever.
Download the latest version from the releases page.
Download replayer-<version>-win64.zip, unzip it anywhere and start
replayer.exe. Nothing else needs to be installed.
Download replayer-<version>-x86_64.AppImage, make it executable and run it:
chmod +x replayer-*-x86_64.AppImage
./replayer-*-x86_64.AppImageIt runs on most distributions from Ubuntu 24.04 on.
Install replayer (latest
release) or replayer-git
(latest commit) with an AUR helper such as paru or yay:
paru -S replayerOr build it by hand:
git clone https://aur.archlinux.org/replayer.git
cd replayer
makepkg -siTo build Replayer yourself, see Building from source below.
If Replayer helps you land that jump, you can buy me a coffee. Thank you!
| Key | Action |
|---|---|
| Down / Up (PgDn / PgUp) | Next / previous clip |
| Ctrl+click, Shift+click | Select clips to compare |
| Right-click a clip | Split, color or hide a clip |
| Ctrl+E | Export a frame, video or GIF |
| Space | Play / pause |
| S | Stop (rewind to start) |
| L | Loop clip on / off |
. / , |
Next / previous frame |
| Right / Left | Seek forward / back 1 s |
| Shift+Right / Left | Seek forward / back 5 s |
+ / -, mouse wheel |
Zoom in / out |
0 |
Reset zoom |
| Drag on the video | Pan (when zoomed in) |
| F, F11, double-click | Toggle full screen |
| Esc | Leave full screen / put tool away |
| Ctrl+Z | Undo drawing or measurement |
| Ctrl+Y, Ctrl+Shift+Z | Redo drawing or measurement |
| Ctrl+Delete | Clear all annotations of the clip |
| Ctrl+O | Open folder |
| Ctrl+Shift+O | Open a single file (and its folder) |
When comparing clips, the playback shortcuts act on all of them at once.
For a full description of every function, see the user guide (also in Replayer under Help → User Guide).
Requirements and build instructions
- Qt 6.2 or newer (Core, Gui, Widgets, OpenGLWidgets, Svg)
- FFmpeg 5.1 or newer (libavcodec, libavformat, libavutil, libswscale)
- CMake 3.21+, pkg-config, a C++17 compiler
- OpenGL 3.0 (or 2.1 with
ARB_texture_rg)
On Debian/Ubuntu:
sudo apt install build-essential cmake ninja-build pkg-config qt6-base-dev qt6-svg-dev \
libavcodec-dev libavformat-dev libavutil-dev libswscale-dev
cmake -S . -B build -G Ninja
cmake --build build
./build/replayer [folder or file]To package an AppImage, run ./build.sh. The result is
dist/replayer-<version>-x86_64.AppImage.
Requires Visual Studio 2022 with the C++ workload, CMake, Qt 6 for MSVC 2022
64-bit (Qt Online Installer or aqtinstall)
and a shared FFmpeg build with MSVC import libraries, e.g.
ffmpeg-*-win64-lgpl-shared from
BtbN/FFmpeg-Builds. Without
pkg-config, CMake finds FFmpeg through -DFFMPEG_ROOT=<dir>.
.\build.ps1 -QtDir D:\dev\Qt\6.10.3\msvc2022_64 -FFmpegDir D:\dev\ffmpegThe paths can also be set with QT_DIR and FFMPEG_DIR. The result is a
portable folder and dist\replayer-<version>-win64.zip with all Qt, FFmpeg
and MSVC runtime DLLs included.
The version comes from the git tags: a build 5 commits after v2.0.0 is
2.0.0-5-gabc1234. To set it explicitly, pass -DREPLAYER_VERSION=2.0.0 to
CMake, -Version 2.0.0 to build.ps1, or set REPLAYER_VERSION for
build.sh.
To publish a release, push a tag like v2.0.0. The release workflow builds
both packages with version 2.0.0 and attaches them to the GitHub release
2.0.0. Tags like v2.0.0-rc1 and 0.x versions become pre-releases.
Set REPLAYER_HWDEC to choose the decoder: none forces software
decoding, and a device name such as vaapi, cuda, d3d11va or
videotoolbox selects that API. The info panel shows the decoder in use next
to the codec.
Replayer is free software, licensed under the GNU General Public License v3.0. You may use, share and change it, but anything you distribute that is based on it must be released under the same license, with its source code.
Replayer uses Qt (LGPLv3) and FFmpeg (LGPL on Windows, GPL in the AppImage). See THIRD-PARTY-NOTICES.md for details.