tev — The EDR Viewer   

High dynamic range (HDR) image viewer for people who care about colors.

• Lightning fast: starts up instantly, loads hundreds of images in seconds.
• Accurate: understands HDR and color profiles (ICC, CICP, etc.). Displays HDR on all operating systems.
• Versatile: supports many file formats, histograms, pixel-peeping, tonemaps, error metrics, etc.

A false-color comparison of two multi-layer OpenEXR images of a beach ball. Image courtesy of openexr-images.

Installation

Download tev for - Windows: Installer (.msi), portable executable (.exe) - Linux: AppImage (.appimage) (how to run AppImages) - macOS: Installer (.dmg)

Or install tev via package managers:

macOS

bash brew install --cask tev

Arch Linux (Arch User Repository)

bash yay -S tev

NixOS

```nix

In your inputs

inputs = { ... tev = { url = "https://github.com/tom94/tev"; type = "git"; submodules = true; }; };

In your configuration

environment.systemPackages = with pkgs; [ ... inputs.tev.packages.${system}.default ]; ```

Install from source

Or build and install tev from source. See the building tev section below for details. TL;DR: sh $ git clone --recursive https://github.com/Tom94/tev $ cmake . -B build $ cmake --build build --config Release -j $ cmake --install build

Usage

Graphical User Interface

Images can be opened via a file dialog or by dragging them into tev. They can be reloaded, closed, or filtered at any time, so don't worry about opening more images than exactly needed.

Select an image by left-clicking it, and optionally select a reference image to compare the current selection to by right-clicking. For convenience, the current selection can be moved with the Up/Down or the 1-9 keys. For a comprehensive list of keyboard shortcuts click the little "?" icon at the top (or press "h") or view this online visualization.

If the interface seems overwhelming, you can hover any controls to view an explanatory tooltip.

Command Line

tev takes images as positional command-line arguments: sh $ tev foo.exr bar.exr

By default, all layers and channels are loaded, but individual layers or channels can also be specified. In the following example, the depth layer of foo.exr and the r, g, and b channels of foo.exr and bar.exr are loaded. sh $ tev :depth foo.exr :r,g,b foo.exr bar.exr

Other command-line arguments exist (e.g. for starting tev with a pre-set exposure value). For a list of all arguments simply invoke sh $ tev -h

Over the Network

tev can also be controlled remotely over the network using a simple TCP-based protocol.

The --host argument specifies the IP and port tev is listening to. By default, tev only accepts connections from localhost (127.0.0.1:14158), which is useful, for example, as frontend for a supported renderer like pbrt version 4.

The following operations exist:

| Operation | Function | :--- | :---------- | OpenImage | Opens an image from a specified path on the machine tev is running on. | CreateImage | Creates a blank image with a specified name, size, and set of channels. If an image with the specified name already exists, it is overwritten. | UpdateImage | Updates the pixels in a rectangular region. | CloseImage | Closes a specified image. | ReloadImage | Reloads an image from a specified path on the machine tev is running on. | VectorGraphics | Draws vector graphics over a specified image.

tev's network protocol is already implemented in the following languages: - C++ (by Simon Kallweit) - Python (initial implementation by Tomáš Iser) - pip install tevclient - Rust (by Karel Peeters)

If using these implementations is not an option, it's easy to write your own one. Each packet has the simple form [uint32_t total_length_in_bytes][byte operation_type][byte[] operation_specific_payload] where integers are encoded in little endian.

There are helper functions in Ipc.cpp (IpcPacket::set*) that show exactly how each packet has to be assembled. These functions do not rely on external dependencies, so you can copy and paste them into your project to interface with tev.

Building tev

All that is required for building tev is CMake and a C++20-compatible compiler. On Windows, that's Visual Studio 2019 and newer. On Linux and macOS, your system's GCC or Clang compiler is likely sufficient.

Most Linux distributions additionally require xorg, wayland, gl, and dbus. On Ubuntu/Debian simply call sh $ apt-get install cmake libdbus-1-dev libffi-dev libglu1-mesa-dev libwayland-dev libxkbcommon-dev nasm wayland-protocols xorg-dev

Once all dependencies are installed, begin by cloning this repository and all its submodules using the following command: sh $ git clone --recursive https://github.com/Tom94/tev

Then, use CMake as follows: sh $ cmake . -B build $ cmake --build build --config Release -j

Afterwards, tev can be installed via sh $ cmake --install build or you can create a standalone installer (Windows, macOS) / AppImage (Linux) with sh $ cpack --config build/CPackConfig.cmake

File Formats

• EXR (via OpenEXR)
• Ultra HDR JPEG (e.g. pictures from newer Android phones; via libultrahdr)
• JPEG XL (via libjxl. Shoutout to Johnathon Selstad for adding support!)
  • Supports both lossy and lossless compression with full HDR capabilities
• JPEG (via libjpeg-turbo)
• PNG, APNG (via libpng)
• PFM (compatible with Netbpm)
• QOI (via qoi. Shoutout to Tiago Chaves for adding support!)
• DDS (via DirectXTex; Windows only. Shoutout to Craig Kolb for adding support!)
  • Supports BC1-BC7 compressed formats.
• WEBP (via libwebp)
• TIFF, DNG (via libtiff; only some DNG files supported)
• AVIF (via aom+libheif)
• HEIC (e.g. pictures from iPhones; via libde265+libheif; disabled in binary release. You must build tev yourself with the TEV_SUPPORT_HEIC CMake option. Check patent laws in your jurisdiction before enabling this feature.)
• HDR, BMP, GIF, PIC, PNM, PSD, TGA (via stb_image)

License

tev is available under the GPLv3 license, which you can find in the LICENSE.txt file. TL;DR.

Older versions of tev (v1.30 and earlier) are available under the BSD 3-Clause license. If required, use git tags to check out these older versions.