add platform specific documentation

README.md

@@ -1,4 +1,4 @@
-# FFmpegKit ![GitHub release](https://img.shields.io/badge/release-v4.4-blue.svg) ![Maven Central](https://img.shields.io/maven-central/v/com.arthenica/ffmpeg-kit-min) ![CocoaPods](https://img.shields.io/cocoapods/v/ffmpeg-kit-min) [![Build Status](https://travis-ci.org/tanersener/ffmpeg-kit.svg?branch=master)](https://travis-ci.org/tanersener/ffmpeg-kit)
+# FFmpegKit ![GitHub release](https://img.shields.io/badge/release-v4.4-blue.svg) ![Maven Central](https://img.shields.io/maven-central/v/com.arthenica/ffmpeg-kit-min) ![CocoaPods](https://img.shields.io/cocoapods/v/ffmpeg-kit-ios-min) [![Build Status](https://travis-ci.org/tanersener/ffmpeg-kit.svg?branch=master)](https://travis-ci.org/tanersener/ffmpeg-kit)
 
 FFmpeg Kit for applications.
 
@@ -24,13 +24,22 @@ FFmpeg Kit for applications.
 
 - Licensed under `LGPL 3.0`, or `GPL v3.0` if GPL licensed libraries are enabled
 
+#### 1.1 Android
+
+See [Android](https://github.com/tanersener/ffmpeg-kit/tree/development/android).
+
+#### 1.2 iOS, macOS, tvOS
+
+See [Apple](https://github.com/tanersener/ffmpeg-kit/tree/development/apple).
+
 ### 2. Build Scripts
 Use `android.sh`, `ios.sh`, `macos.sh` and `tvos.sh` to build `FFmpegKit` for each platform.
 
 All four scripts support additional options to enable external libraries or disable platform architectures.
 
-Refer to `Android` page for `Android` devices and `Apple` page for `iOS`, `macOS`, `tvOS` devices to see the 
-prerequisites for each platform.
+Refer to [Android](https://github.com/tanersener/ffmpeg-kit/tree/development/android) page for `Android` devices and
+[Apple](https://github.com/tanersener/ffmpeg-kit/tree/development/apple) page for `iOS`, `macOS`, `tvOS` devices to see 
+the prerequisites for each platform.
 
 ### 3. FFmpegKit Library
 
@@ -40,6 +49,10 @@ provides additional features on top of `FFmpeg` to enable platform specific reso
 `Android` library has a `Java` API and `Apple` libraries (`iOS`, `macOS`, `tvOS`) have an `Objective-C` API, 
 which are identical.
 
+See [Android](https://github.com/tanersener/ffmpeg-kit/tree/development/android) page to learn how the `Java` API 
+can be used on `Android` devices and [Apple](https://github.com/tanersener/ffmpeg-kit/tree/development/apple) page to 
+learn more about `Objective-C` API for `iOS`, `macOS`, `tvOS` devices.
+
 ### 4. Binary Packages
 
 There are eight different `ffmpeg-kit` packages distributed on 

android/README.md

@@ -0,0 +1,184 @@
+# FFmpegKit for Android
+
+### 1. Features
+- Supports
+  - `API Level 16+`
+  - `arm-v7a`, `arm-v7a-neon`, `arm64-v8a`, `x86` and `x86_64` architectures
+  - `zlib` and `MediaCodec` system libraries
+- Can handle Storage Access Framework (SAF) uris
+- Camera access on [supported devices](https://developer.android.com/ndk/guides/stable_apis#camera)
+- Builds shared native libraries (.so)
+- Creates Android archive with .aar extension
+
+### 2. Building
+
+Run `android.sh` at project root directory to build `ffmpeg-kit` and `ffmpeg` shared libraries. 
+
+#### 2.1 Prerequisites
+
+`android.sh` requires the following packages and tools. 
+
+1. Install Android tools listed below.
+    - **Android SDK Build Tools**
+    - **Android NDK r21e** or later with LLDB and CMake
+
+2. Use your package manager (apt, yum, dnf, brew, etc.) to install the following packages.
+
+    ```
+    autoconf automake libtool pkg-config curl cmake gcc gperf texinfo yasm nasm bison autogen git wget autopoint meson ninja
+    ```
+
+3. Set `ANDROID_SDK_ROOT` and `ANDROID_NDK_ROOT` environment variables.
+    ```
+    export ANDROID_SDK_ROOT=<Android SDK Path>
+    export ANDROID_NDK_ROOT=<Android NDK Path>
+    ```
+
+4. `android.sh` needs network connectivity and internet access to `github.com` in order to download the source code 
+   of all libraries except `ffmpeg-kit`.
+
+#### 2.2 Options
+
+Use `--enable-<library name>` flags to support additional external or system libraries and
+`--disable-<architecture name>` to disable architectures you don't want to build.
+
+```
+./android.sh --enable-fontconfig --disable-arm-v7a-neon
+```
+
+Run `--help` to see all available build options.
+
+#### 2.3 LTS Binaries
+
+Use `--lts` option to build lts binaries for each architecture.
+
+#### 2.4 Build Output
+
+All libraries created by `android.sh` can be found under the `prebuilt` directory.
+
+- `Android` archive (.aar file) for `Main` builds is located under the `bundle-android-aar` folder.
+- `Android` archive (.aar file) for `LTS` builds is located under the `bundle-android-aar-lts` folder.
+
+### 3. Using
+
+#### 3.1 Android API
+
+1. Declare `mavenCentral` repository and add `FFmpegKit` dependency to your `build.gradle` in 
+   `ffmpeg-kit-<package name>` pattern. Use one of the `FFmpegKit` package names given in the 
+   project [README](https://github.com/tanersener/ffmpeg-kit).
+
+    ```
+    repositories {
+        mavenCentral()
+    }
+
+    dependencies {
+        implementation 'com.arthenica:ffmpeg-kit-full:4.4.LTS'
+    }
+    ```
+
+2. Execute synchronous FFmpeg commands.
+
+    ```
+    import com.arthenica.ffmpegkit.FFmpegKit;
+    import com.arthenica.ffmpegkit.ReturnCode;
+
+    FFmpegSession session = FFmpegKit.execute("-i file1.mp4 -c:v mpeg4 file2.mp4");
+    if (ReturnCode.isSuccess(session.getReturnCode())) {
+        // SUCCESS
+    } else if (ReturnCode.isCancel(session.getReturnCode())) {
+        // CANCEL
+    } else {
+        // FAILURE
+        Log.d(TAG, String.format("Command failed with state %s and rc %s.%s", session.getState(), session.getReturnCode(), session.getFailStackTrace()));
+    }
+    ```
+
+3. Execute asynchronous FFmpeg commands by providing session specific execute/log/session callbacks.
+
+    ```
+    FFmpegKit.executeAsync("-i file1.mp4 -c:v mpeg4 file2.mp4", new ExecuteCallback() {
+
+        @Override
+        public void apply(Session session) {
+            SessionState state = session.getState();
+            ReturnCode returnCode = session.getReturnCode();
+
+            // CALLED WHEN SESSION IS EXECUTED
+
+            Log.d(TAG, String.format("FFmpeg process exited with state %s and rc %s.%s", state, returnCode, session.getFailStackTrace()));
+        }
+    }, new LogCallback() {
+
+        @Override
+        public void apply(com.arthenica.ffmpegkit.Log log) {
+
+            // CALLED WHEN SESSION PRINTS LOGS
+
+        }
+    }, new StatisticsCallback() {
+
+        @Override
+        public void apply(Statistics statistics) {
+
+            // CALLED WHEN SESSION GENERATES STATISTICS
+
+        }
+    });
+    ```
+
+4. Execute synchronous FFprobe commands.
+
+    ```
+    FFprobeSession session = FFprobeKit.execute(ffprobeCommand);
+
+    if (!ReturnCode.isSuccess(session.getReturnCode())) {
+        Log.d(TAG, "Command failed. Please check output for the details.");
+    }
+    ```
+
+5. Get session output.
+
+    ```
+    Session session = FFmpegKit.execute("-i file1.mp4 -c:v mpeg4 file2.mp4");
+    Log.d(TAG, session.getOutput());
+    ```
+
+6. Stop ongoing FFmpeg operations.
+
+    - Stop all executions
+        ```
+        FFmpegKit.cancel();
+        ```
+    - Stop a specific session
+        ```
+        FFmpegKit.cancel(sessionId);
+        ```
+
+7. Get media information for a file.
+
+    ```
+    MediaInformationSession mediaInformation = FFprobeKit.getMediaInformation("<file path or uri>");
+    mediaInformation.getMediaInformation();
+    ```
+
+8. List previous FFmpeg sessions.
+
+   ```
+   List<FFmpegSession> ffmpegSessions = FFmpegKit.listSessions();
+   for (int i = 0; i < ffmpegSessions.size(); i++) {
+      FFmpegSession session = ffmpegSessions.get(i);
+      Log.d(TAG, String.format("Session %d = id:%d, startTime:%s, duration:%s, state:%s, returnCode:%s.",
+              i,
+              session.getSessionId(),
+              session.getStartTime(),
+              session.getDuration(),
+              session.getState(),
+              session.getReturnCode()));
+   }
+   ```
+
+### 4. Test Application
+
+You can see how `FFmpegKit` is used inside an application by running test applications developed under the
+[FFmpegKit Test](https://github.com/tanersener/ffmpeg-kit-test) project.