Google Is Bringing UltraHDR Shooting to More Third-Party Apps

TapTechNews July 14th news, according to AndroidAuthority report, Google is bringing the UltraHDR shooting function to more third-party applications.

We are familiar with the camera HDR processing technology which actually uses computational photography and image stacking to achieve an HDR-like effect, but the generated image is still in standard dynamic range (SDR). However, starting from Android 14, many Android phones can start to shoot true HDR photos using a format called UltraHDR. But currently, many third-party applications with built-in camera functions cannot shoot UltraHDR photos yet, but this situation is about to change.

According to TapTechNews understanding, UltraHDR is a new image format developed by Google and based on the popular JPEG format. Due to being based on JPEG, almost all devices can view UltraHDR images whether they have an HDR display or not. But the special thing about UltraHDR images is that when they are viewed on a device with an HDR display, the HDR version of the image will be shown, providing more vivid and higher contrast colors.

This is because UltraHDR images are JPEG files with embedded metadata for HDR gain mapping, and applications can apply it to the basic SDR version image also contained in the file. Since this HDR gain mapping must be created and saved to the metadata of the JPEG file when creating the image, existing camera applications need to be updated to support this step. Google created an API in Android 14 for camera applications to do this, but this API is part of Camera2, not CameraX, which limits its popularity.

Camera2 is an API bundled with the Android operating system framework and is designed for applications that want to deploy advanced camera functions, such as mature third-party camera applications with professional-level control of multiple lenses. While CameraX is an API bundled with the Jetpack support library and is more suitable for applications that only need to access the camera for auxiliary functions, such as social media applications that can quickly take photos to share with friends. Developers can choose which camera API to use, but since new camera functions are first developed for Camera2, developers relying on CameraX need to wait for Google to port this function. Due to the more concise design of CameraX, some Camera2 functions will never be ported to CameraX, but fortunately, Ultra HDR shooting support is not one of them.

Google announced at this year's I/O 2024 Developer Conference that they will update their CameraX library to support UltraHDR image shooting. Looking at the version notes of the CameraX library, it can be seen that preliminary support for UltraHDR shooting was added in the 1.4.0-alpha05 version released in April. The 1.4.0 version of CameraX will introduce new output format APIs to the ImageCapture and ImageCaptureCapabilities classes. These APIs include the getSupportedOutputFormats method in ImageCaptureCapabilities for querying whether the device can shoot UltraHDR images; theoretically devices running Android 14 or higher should be able to, as the encoder library is bundled with this operating system version, but currently it cannot be 100% sure. If the output format is set to OUTPUT_FORMAT_JPEG_ULTRA_HDR on a device that supports UltraHDR image shooting, then the CameraX library will shoot UltraHDR images in the JPEG/R image format. (The R in JPEG/R represents recovery mapping, referring to the HDR gain mapping embedded in the JPEG file.)

As described in the API description, for old applications or devices with SDR displays, these images will be seamlessly displayed as regular JPEG files, and for applications and devices that have been fully updated to support this format, they will be displayed as HDR images. Currently, there are not many applications that support Ultra HDR, and only Google Chrome browser fully supports it on Android and desktop. Devices that can fully display UltraHDR images include Samsung Galaxy S24 series, Google Pixel 7 and Pixel 8 series, OnePlus 12, and several other devices. Some newer Windows computers with HDR displays can also display UltraHDR images.