背景
在上一次的初次使用cmake編譯jni后踱启，這次cmake文件再次升級(jí)。利用網(wǎng)上的代碼來(lái)編譯一個(gè)簡(jiǎn)單的播放器。本文參照 Android+FFmpeg+ANativeWindow視頻解碼播放 一文埠偿，在cmake下重新編譯透罢。特將過(guò)程分享給大家。
gradle 配置
apply plugin: 'com.android.application'
android {
compileSdkVersion 22
buildToolsVersion "23.0.1"
//sourceSets.main.jni.srcDirs = ['jniLibs']
defaultConfig {
applicationId "jonesx.videoplayer"
minSdkVersion 9
targetSdkVersion 22
versionCode 1
versionName "1.0"
ndk {
abiFilters 'armeabi'
}
externalNativeBuild {
cmake {
arguments '-DANDROID_TOOLCHAIN=clang','-DANDROID_STL=gnustl_static'
}
}
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
externalNativeBuild {
cmake {
path "src/main/cpp/CMakeLists.txt"
}
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
compile 'com.android.support:appcompat-v7:22.2.1'
compile 'com.android.support:design:22.2.1'
}
cmake 配置
- 整個(gè)工程的層級(jí)冠蒋。
框架.png
- cmake配置文件
CMakeLists.txt
cmake_minimum_required(VERSION 3.4.1)
set(lib_src_DIR ${CMAKE_SOURCE_DIR}/../jniLibs/${ANDROID_ABI})
include_directories(
${CMAKE_SOURCE_DIR}/include
)
add_library(avcodec-57_lib SHARED IMPORTED)
set_target_properties(avcodec-57_lib PROPERTIES IMPORTED_LOCATION
${lib_src_DIR}/libavcodec-57.so)
add_library(avformat-57_lib SHARED IMPORTED)
set_target_properties(avformat-57_lib PROPERTIES IMPORTED_LOCATION
${lib_src_DIR}/libavformat-57.so)
add_library(avutil-55_lib SHARED IMPORTED)
set_target_properties(avutil-55_lib PROPERTIES IMPORTED_LOCATION
${lib_src_DIR}/libavutil-55.so)
add_library(swresample-2_lib SHARED IMPORTED)
set_target_properties(swresample-2_lib PROPERTIES IMPORTED_LOCATION
${lib_src_DIR}/libswresample-2.so)
add_library(swscale-4_lib SHARED IMPORTED)
set_target_properties(swscale-4_lib PROPERTIES IMPORTED_LOCATION
${lib_src_DIR}/libswscale-4.so)
# build application's shared lib
add_library(VideoPlayer SHARED
VideoPlayer.cpp)
# Include libraries needed for VideoPlayer lib
target_link_libraries(VideoPlayer
log
android
avcodec-57_lib
avformat-57_lib
avutil-55_lib
swresample-2_lib
swscale-4_lib)
解釋下羽圃，這里添加了依賴的so庫(kù)，注意路徑呀抖剿，我在這里坑了半天朽寞，還有同事拯救了我。
add_library(swscale-4_lib SHARED IMPORTED)
set_target_properties(swscale-4_lib PROPERTIES IMPORTED_LOCATION
${lib_src_DIR}/libswscale-4.so)
最后牙躺，不要忘了愁憔，target_link_libraries中添加對(duì)應(yīng)的庫(kù)。
VideoPlayer.cpp
//
// Created by Jonesx on 2016/3/20.
//
#include <jni.h>
#include "VideoPlayer.h"
#include <android/log.h>
#include <android/native_window.h>
#include <android/native_window_jni.h>
extern "C"{
#include "libavcodec/avcodec.h"
#include "libavformat/avformat.h"
#include "libswscale/swscale.h"
#include "libavutil/imgutils.h"
};
#define LOG_TAG "videoplayer"
#define LOGD(...) __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG, __VA_ARGS__)
JNIEXPORT jint JNICALL Java_jonesx_videoplayer_VideoPlayer_play
(JNIEnv *env, jclass clazz, jobject surface) {
LOGD("play");
// sd卡中的視頻文件地址,可自行修改或者通過(guò)jni傳入
char *file_name = "/sdcard/test.mp4";
av_register_all();
AVFormatContext *pFormatCtx = avformat_alloc_context();
// Open video file
if (avformat_open_input(&pFormatCtx, file_name, NULL, NULL) != 0) {
LOGD("Couldn't open file:%s\n", file_name);
return -1; // Couldn't open file
}
// Retrieve stream information
if (avformat_find_stream_info(pFormatCtx, NULL) < 0) {
LOGD("Couldn't find stream information.");
return -1;
}
// Find the first video stream
int videoStream = -1, i;
for (i = 0; i < pFormatCtx->nb_streams; i++) {
if (pFormatCtx->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO
&& videoStream < 0) {
videoStream = i;
}
}
if (videoStream == -1) {
LOGD("Didn't find a video stream.");
return -1; // Didn't find a video stream
}
// Get a pointer to the codec context for the video stream
AVCodecContext *pCodecCtx = pFormatCtx->streams[videoStream]->codec;
// Find the decoder for the video stream
AVCodec *pCodec = avcodec_find_decoder(pCodecCtx->codec_id);
if (pCodec == NULL) {
LOGD("Codec not found.");
return -1; // Codec not found
}
if (avcodec_open2(pCodecCtx, pCodec, NULL) < 0) {
LOGD("Could not open codec.");
return -1; // Could not open codec
}
// 獲取native window
ANativeWindow *nativeWindow = ANativeWindow_fromSurface(env, surface);
// 獲取視頻寬高
int videoWidth = pCodecCtx->width;
int videoHeight = pCodecCtx->height;
// 設(shè)置native window的buffer大小,可自動(dòng)拉伸
ANativeWindow_setBuffersGeometry(nativeWindow, videoWidth, videoHeight,
WINDOW_FORMAT_RGBA_8888);
ANativeWindow_Buffer windowBuffer;
if (avcodec_open2(pCodecCtx, pCodec, NULL) < 0) {
LOGD("Could not open codec.");
return -1; // Could not open codec
}
// Allocate video frame
AVFrame *pFrame = av_frame_alloc();
// 用于渲染
AVFrame *pFrameRGBA = av_frame_alloc();
if (pFrameRGBA == NULL || pFrame == NULL) {
LOGD("Could not allocate video frame.");
return -1;
}
// Determine required buffer size and allocate buffer
// buffer中數(shù)據(jù)就是用于渲染的,且格式為RGBA
int numBytes = av_image_get_buffer_size(AV_PIX_FMT_RGBA, pCodecCtx->width, pCodecCtx->height,
1);
uint8_t *buffer = (uint8_t *) av_malloc(numBytes * sizeof(uint8_t));
av_image_fill_arrays(pFrameRGBA->data, pFrameRGBA->linesize, buffer, AV_PIX_FMT_RGBA,
pCodecCtx->width, pCodecCtx->height, 1);
// 由于解碼出來(lái)的幀格式不是RGBA的,在渲染之前需要進(jìn)行格式轉(zhuǎn)換
struct SwsContext *sws_ctx = sws_getContext(pCodecCtx->width,
pCodecCtx->height,
pCodecCtx->pix_fmt,
pCodecCtx->width,
pCodecCtx->height,
AV_PIX_FMT_RGBA,
SWS_BILINEAR,
NULL,
NULL,
NULL);
int frameFinished;
AVPacket packet;
while (av_read_frame(pFormatCtx, &packet) >= 0) {
// Is this a packet from the video stream?
if (packet.stream_index == videoStream) {
// Decode video frame
avcodec_decode_video2(pCodecCtx, pFrame, &frameFinished, &packet);
// 并不是decode一次就可解碼出一幀
if (frameFinished) {
// lock native window buffer
ANativeWindow_lock(nativeWindow, &windowBuffer, 0);
// 格式轉(zhuǎn)換
sws_scale(sws_ctx, (uint8_t const *const *) pFrame->data,
pFrame->linesize, 0, pCodecCtx->height,
pFrameRGBA->data, pFrameRGBA->linesize);
// 獲取stride
uint8_t *dst = (uint8_t *) windowBuffer.bits;
int dstStride = windowBuffer.stride * 4;
uint8_t *src = (pFrameRGBA->data[0]);
int srcStride = pFrameRGBA->linesize[0];
// 由于window的stride和幀的stride不同,因此需要逐行復(fù)制
int h;
for (h = 0; h < videoHeight; h++) {
memcpy(dst + h * dstStride, src + h * srcStride, srcStride);
}
ANativeWindow_unlockAndPost(nativeWindow);
}
}
av_packet_unref(&packet);
}
av_free(buffer);
av_free(pFrameRGBA);
// Free the YUV frame
av_free(pFrame);
// Close the codecs
avcodec_close(pCodecCtx);
// Close the video file
avformat_close_input(&pFormatCtx);
return 0;
}
這里是正常的ffmpeg編解碼流程孽拷。參見(jiàn)雷神
Paste_Image.png
這里又有一個(gè)坑點(diǎn)吨掌，由于我使用的是c++ 編譯器clang，而ffmpeg的so庫(kù)均為c語(yǔ)言的脓恕，故需添加
extern "C"{
include "libavcodec/avcodec.h"
include "libavformat/avformat.h"
include "libswscale/swscale.h"
include "libavutil/imgutils.h"
};
如果這里沒(méi)添加extern "C"{}膜宋，即不是按C語(yǔ)言編譯，就會(huì)存在undefined reference錯(cuò)誤炼幔。下面是使用
VideoPlayer.java
package jonesx.videoplayer;
/**
* Created by Jonesx on 2016/3/12.
*/
public class VideoPlayer {
static {
System.loadLibrary("VideoPlayer");
}
public static native int play(Object surface);
}
MainActivity.java
這里使用的SufaceView來(lái)進(jìn)行播放秋茫。
public class MainActivity extends AppCompatActivity implements SurfaceHolder.Callback {
SurfaceHolder surfaceHolder;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
SurfaceView surfaceView = (SurfaceView) findViewById(R.id.surface_view);
surfaceHolder = surfaceView.getHolder();
surfaceHolder.addCallback(this);
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
new Thread(new Runnable() {
@Override
public void run() {
VideoPlayer.play(surfaceHolder.getSurface());
}
}).start();
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
}
}
灰常簡(jiǎn)單的xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:context=".MainActivity"
tools:showIn="@layout/activity_main">
<SurfaceView
android:id="@+id/surface_view"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</RelativeLayout>
收工，看效果乃秀，非常簡(jiǎn)陋肛著，沒(méi)暫停什么滴。
ps 補(bǔ)充源碼 https://github.com/nothinglhw/cmakeDemo
test.png
