1*89a0ef05SAndroid Build Coastguard Workerlibultrahdr is an image compression library that uses gain map technology 2*89a0ef05SAndroid Build Coastguard Workerto store and distribute HDR images. Conceptually on the encoding side, the 3*89a0ef05SAndroid Build Coastguard Workerlibrary accepts SDR and HDR rendition of an image and from these a Gain Map 4*89a0ef05SAndroid Build Coastguard Worker(quotient between the two renditions) is computed. The library then uses 5*89a0ef05SAndroid Build Coastguard Workerbackward compatible means to store the base image (SDR), gain map image and 6*89a0ef05SAndroid Build Coastguard Workersome associated metadata. Legacy readers that do not support handling the 7*89a0ef05SAndroid Build Coastguard Workergain map image and/or metadata, will display the base image. Readers that 8*89a0ef05SAndroid Build Coastguard Workersupport the format combine the base image with the gain map and render a 9*89a0ef05SAndroid Build Coastguard Workerhigh dynamic range image on compatible displays. 10*89a0ef05SAndroid Build Coastguard Worker 11*89a0ef05SAndroid Build Coastguard WorkerFor additional information, see android hdr-image-format 12*89a0ef05SAndroid Build Coastguard Workerhttps://developer.android.com/guide/topics/media/platform/hdr-image-format. 13