https://opensource.contentauthenticity.org/assets/js/06ce38f1.136713eb.js

1"use strict";(globalThis.webpackChunkopensource_contentauth_org=globalThis.webpackChunkopensource_contentauth_org||[]).push([[6231],{4969:(e,n,i)=>{i.r(n),i.d(n,{assets:()=>c,contentTitle:()=>o,default:()=>h,frontMatter:()=>s,metadata:()=>t,toc:()=>d});const t=JSON.parse('{"id":"sdk-repos/c2pa-android-example/README","title":"C2PA Android example app","description":"The c2pa-android-example repository contains a prototype Android application demonstrating how to capture photos and videos, embed Content Credentials, and then sign them.","source":"@site/docs/sdk-repos/c2pa-android-example/README.md","sourceDirName":"sdk-repos/c2pa-android-example","slug":"/sdk-repos/c2pa-android-example/","permalink":"/docs/sdk-repos/c2pa-android-example/","draft":false,"unlisted":false,"editUrl":"https://github.com/contentauth/c2pa-android-example/edit/main/README.md","tags":[],"version":"current","frontMatter":{},"sidebar":"docs","previous":{"title":"C2PA Android library","permalink":"/docs/sdk-repos/c2pa-android/"},"next":{"title":"CAWG on mobile","permalink":"/docs/cawg-mobile"}}');var r=i(4848),a=i(8453);const s={},o="C2PA Android example app",c={},d=[{value:"Key Features",id:"key-features",level:2},{value:"Tech stack and core libraries",id:"tech-stack-and-core-libraries",level:2},{value:"Project Architecture",id:"project-architecture",level:2},{value:"UI layer (/ui)",id:"ui-layer-ui",level:3},{value:"ViewModel layer (/ui)",id:"viewmodel-layer-ui",level:3},{value:"C2PA signing logic (/c2pa_signing)",id:"c2pa-signing-logic-c2pa_signing",level:3},{value:"General utilities (/utils)",id:"general-utilities-utils",level:3}];function l(e){const n={a:"a",code:"code",h1:"h1",h2:"h2",h3:"h3",header:"header",li:"li",p:"p",strong:"strong",ul:"ul",...(0,a.R)(),...e.components};return(0,r.jsxs)(r.Fragment,{children:[(0,r.jsx)(n.header,{children:(0,r.jsx)(n.h1,{id:"c2pa-android-example-app",children:"C2PA Android example app"})}),"\n",(0,r.jsxs)(n.p,{children:["The ",(0,r.jsx)(n.a,{href:"https://github.com/contentauth/c2pa-android-example",children:"c2pa-android-example repository"})," contains a prototype Android application demonstrating how to capture photos and videos, embed Content Credentials, and then sign them."]}),"\n",(0,r.jsx)(n.p,{children:"The app is built using modern Android development practices with Jetpack Compose and CameraX."}),"\n",(0,r.jsx)(n.h2,{id:"key-features",children:"Key Features"}),"\n",(0,r.jsxs)(n.ul,{children:["\n",(0,r.jsxs)(n.li,{children:[(0,r.jsx)(n.strong,{children:"Photo and video capture"}),": Uses CameraX for a robust camera implementation."]}),"\n",(0,r.jsxs)(n.li,{children:[(0,r.jsx)(n.strong,{children:"C2PA signing"}),": Signs captured media with RSA keys to create a C2PA manifest, ensuring content authenticity."]}),"\n",(0,r.jsxs)(n.li,{children:[(0,r.jsx)(n.strong,{children:"In-place signing"}),": Correctly handles modern Android Scoped Storage by signing files from ",(0,r.jsx)(n.code,{children:"content://"})," URIs in-place using a temporary file strategy."]}),"\n",(0,r.jsxs)(n.li,{children:[(0,r.jsx)(n.strong,{children:"Location tagging"}),": Fetches the device's current location and embeds it into the C2PA manifest."]}),"\n",(0,r.jsxs)(n.li,{children:[(0,r.jsx)(n.strong,{children:"Video recording control"}),": Supports starting, pausing, resuming, and stopping video recordings, with the UI reacting to the current state."]}),"\n",(0,r.jsxs)(n.li,{children:[(0,r.jsx)(n.strong,{children:"Runtime permissions"}),": Gracefully handles camera, audio, and location permissions."]}),"\n"]}),"\n",(0,r.jsx)(n.h2,{id:"tech-stack-and-core-libraries",children:"Tech stack and core libraries"}),"\n",(0,r.jsxs)(n.ul,{children:["\n",(0,r.jsx)(n.li,{children:"UI: 100% Jetpack Compose for a declarative and modern UI."}),"\n",(0,r.jsx)(n.li,{children:"Architecture: MVVM (Model-View-ViewModel)."}),"\n",(0,r.jsx)(n.li,{children:"Dependency Injection: Hilt for managing dependencies."}),"\n",(0,r.jsx)(n.li,{children:"Camera: CameraX for camera operations, including preview, image capture, and video capture."}),"\n",(0,r.jsx)(n.li,{children:"Content Authenticity: C2PA Android Library for creating and embedding authenticity manifests."}),"\n",(0,r.jsx)(n.li,{children:"Asynchronicity: Kotlin Coroutines and Flow for managing background tasks and reactive data streams."}),"\n",(0,r.jsx)(n.li,{children:"Permissions: Accompanist Permissions for a clean, composable-based permissions handling flow."}),"\n",(0,r.jsx)(n.li,{children:"Location: Google Play Services Fused Location Provider for accurate and efficie

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