High dynamic range (HDR) image viewer for people who care about colors
README
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 and their quirks: gain maps, aux channels, animation, and more metadata than just EXIF & XMP. Pixel-peep: histograms, tonemaps, error metrics, etc. in any color space.
A false-color comparison of two multi-layer OpenEXR images of a beach ball. Image courtesy of openexr-images.
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:
$ 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.
$ 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
$ 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:
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
AVIF (including gain maps, e.g. HDR pictures from Android; via aom+libheif)
HEIC (including gain maps, e.g. HDR 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.)
A false-color comparison of two multi-layer OpenEXR images of a beach ball. Image courtesy of openexr-images.