Android开机动画制作

在Android手机中开机动画一般位于”system/media“中，可以通过下面的命令获取

adb pull system/media/bootanimation.zip .

解压开机动画里面有个desc.txt文件，配置动画播放的一些参数，以及动画播放的资源图片，下面是desc.txt常用的一些参数

720 1280 25     //720 1280代表图片的像素为720x1280，而25代表帧数，也就每一秒播放25张图;
p 1 60 generic1   //p代表标志符,1代表循环次数为1次,60代表离读取generic2的停顿间隔的帧数（间隔60帧再读取下一部分文件），generic1代表对应的文件夹
p 1 0 generic2
p 0 0 generic3    //这里的generic3循环次数为0,直到系统加载完成前

#p代表定义一个部分。
#p后面的第一个数是重复播放这一部分次数。如果这个数为0，就无限循环播放
#p后面第二个数是播放下一个部分前的延迟帧数
#字符串定义了加载文件的路径

其中generic1表示bootanimation.zip中存放图片资源的目录，
在Android系统启动时，init.c解析init.rc 中定义的”service bootanim /system/bin/bootanimation”

<strong>system/core/rootdir/init.rc</strong></span><span style="font-size:14px;">
service bootanim /system/bin/bootanimation
class core
user graphics
group graphics audio
disabled
oneshot</span>

在frameworks/native/services/surfaceflinger/SurfaceFlinger.cpp中的startBootAnim()启动开机动画

void SurfaceFlinger::startBootAnim() {
// start boot animation
mBootFinished = false;
property_set("service.bootanim.exit", "0");
property_set("ctl.start", "bootanim");  //设置"ctl.start"属性开始播放动画
}

在frameworks/native/services/surfaceflinger/SurfaceFlinger.cpp中的bootFinished()中发送开机动画完成指令

void SurfaceFlinger::bootFinished()
{
property_set("service.bootanim.exit", "1");
property_set("ctl.stop", "bootanim");

}

android对于解析bootanimation.zip的代码位于frameworks/base/cmds/bootanimation/下，在BootAnimation.cpp中的BootAnimation::movie()解析开机动画包。

bool BootAnimation::movie()
{
char value[PROPERTY_VALUE_MAX];
String8 desString;

if (!readFile("desc.txt", desString)) { //读取bootanimation.zip里面的配置文件
return false;
}
char const* s = desString.string();

// Create and initialize an AudioPlayer if we have an audio_conf.txt file
String8 audioConf;
if (readFile("audio_conf.txt", audioConf)) {
mAudioPlayer = new AudioPlayer;
if (!mAudioPlayer->init(audioConf.string())) {
ALOGE("mAudioPlayer.init failed");
mAudioPlayer = NULL;
}
}

Animation animation;

// Parse the description file
for (;;) {
const char* endl = strstr(s, "\n");
if (!endl) break;
String8 line(s, endl - s);
const char* l = line.string();
int fps, width, height, count, pause;
char path[ANIM_ENTRY_NAME_MAX];
char color[7] = "000000"; // default to black if unspecified

char pathType;
if (sscanf(l, "%d %d %d", &width, &height, &fps) == 3) { //开始解析配置文件里每一行的值
// ALOGD("> w=%d, h=%d, fps=%d", width, height, fps);
animation.width = width;
animation.height = height;
animation.fps = fps;
}
else if (sscanf(l, " %c %d %d %s #%6s", &pathType, &count, &pause, path, color) >= 4) {
// ALOGD("> type=%c, count=%d, pause=%d, path=%s, color=%s", pathType, count, pause, path, color);
Animation::Part part;
part.playUntilComplete = pathType == 'c';
part.count = count;
part.pause = pause;
part.path = path;
part.audioFile = NULL;
if (!parseColor(color, part.backgroundColor)) {
ALOGE("> invalid color '#%s'", color);
part.backgroundColor[0] = 0.0f;
part.backgroundColor[1] = 0.0f;
part.backgroundColor[2] = 0.0f;
}
animation.parts.add(part);
}

s = ++endl;
}

// read all the data structures
const size_t pcount = animation.parts.size();
void *cookie = NULL;
if (!mZip->startIteration(&cookie)) {
return false;
}

ZipEntryRO entry;
char name[ANIM_ENTRY_NAME_MAX];
while ((entry = mZip->nextEntry(cookie)) != NULL) {
const int foundEntryName = mZip->getEntryFileName(entry, name, ANIM_ENTRY_NAME_MAX);
if (foundEntryName > ANIM_ENTRY_NAME_MAX || foundEntryName == -1) {
ALOGE("Error fetching entry file name");
continue;
}

const String8 entryName(name);
const String8 path(entryName.getPathDir());
const String8 leaf(entryName.getPathLeaf());
if (leaf.size() > 0) {
for (size_t j=0 ; j<pcount ; j++) {
if (path == animation.parts[j].path) {
int method;
// supports only stored png files
if (mZip->getEntryInfo(entry, &method, NULL, NULL, NULL, NULL, NULL)) {
if (method == ZipFileRO::kCompressStored) {
FileMap* map = mZip->createEntryFileMap(entry);
if (map) {
Animation::Part& part(animation.parts.editItemAt(j));
if (leaf == "audio.wav") {
// a part may have at most one audio file
part.audioFile = map;
} else {
Animation::Frame frame;
frame.name = leaf;
frame.map = map;
part.frames.add(frame);
}
}
}
}
}
}
}
}

mZip->endIteration(cookie);

// clear screen
glShadeModel(GL_FLAT);
glDisable(GL_DITHER);
glDisable(GL_SCISSOR_TEST);
glDisable(GL_BLEND);
glClearColor(0,0,0,1);
glClear(GL_COLOR_BUFFER_BIT);

eglSwapBuffers(mDisplay, mSurface);

glBindTexture(GL_TEXTURE_2D, 0);
glEnable(GL_TEXTURE_2D);
glTexEnvx(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

const int xc = (mWidth - animation.width) / 2;
const int yc = ((mHeight - animation.height) / 2);
nsecs_t lastFrame = systemTime();
nsecs_t frameDuration = s2ns(1) / animation.fps;

Region clearReg(Rect(mWidth, mHeight));
clearReg.subtractSelf(Rect(xc, yc, xc+animation.width, yc+animation.height));

pthread_mutex_init(&mp_lock, NULL);
pthread_cond_init(&mp_cond, NULL);

property_get("persist.sys.silent", value, "null");
if (strncmp(value, "1", 1) != 0) {
playBackgroundMusic();
}
for (size_t i=0 ; i<pcount ; i++) {
const Animation::Part& part(animation.parts[i]);
const size_t fcount = part.frames.size();
glBindTexture(GL_TEXTURE_2D, 0);

/*calculate if we need to runtime save memory
* condition: runtime free memory is less than the textures that will used.
* needSaveMem default to be false
*/
GLint mMaxTextureSize;
bool needSaveMem = false;
GLuint mTextureid;
glGetIntegerv(GL_MAX_TEXTURE_SIZE, &mMaxTextureSize);
//ALOGD("freemem:%ld, %d", getFreeMemory(), mMaxTextureSize);
if(getFreeMemory() < mMaxTextureSize * mMaxTextureSize * fcount / 1024) {
ALOGD("Use save memory method, maybe small fps in actual.");
needSaveMem = true;
glGenTextures(1, &mTextureid);
glBindTexture(GL_TEXTURE_2D, mTextureid);
glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

}

for (int r=0 ; !part.count || r<part.count ; r++) {
// Exit any non playuntil complete parts immediately
if(exitPending() && !part.playUntilComplete)
break;

// only play audio file the first time we animate the part
if (r == 0 && mAudioPlayer != NULL && part.audioFile) {
mAudioPlayer->playFile(part.audioFile);
}

glClearColor(
part.backgroundColor[0],
part.backgroundColor[1],
part.backgroundColor[2],
1.0f);

for (size_t j=0 ; j<fcount && (!exitPending() || part.playUntilComplete) ; j++) {
const Animation::Frame& frame(part.frames[j]);
nsecs_t lastFrame = systemTime();

if (r > 0 && !needSaveMem) {
glBindTexture(GL_TEXTURE_2D, frame.tid);
} else {
if (!needSaveMem && part.count != 1) {
glGenTextures(1, &frame.tid);
glBindTexture(GL_TEXTURE_2D, frame.tid);
glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
}
initTexture(
frame.map->getDataPtr(),
frame.map->getDataLength());
}

if (!clearReg.isEmpty()) {
Region::const_iterator head(clearReg.begin());
Region::const_iterator tail(clearReg.end());
glEnable(GL_SCISSOR_TEST);
while (head != tail) {
const Rect& r(*head++);
glScissor(r.left, mHeight - r.bottom,
r.width(), r.height());
glClear(GL_COLOR_BUFFER_BIT);
}
glDisable(GL_SCISSOR_TEST);
}
glDrawTexiOES(xc, yc, 0, animation.width, animation.height);
eglSwapBuffers(mDisplay, mSurface);

nsecs_t now = systemTime();
nsecs_t delay = frameDuration - (now - lastFrame);
//ALOGD("%lld, %lld", ns2ms(now - lastFrame), ns2ms(delay));
lastFrame = now;

if (delay > 0) {
struct timespec spec;
spec.tv_sec  = (now + delay) / 1000000000;
spec.tv_nsec = (now + delay) % 1000000000;
int err;
do {
err = clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME, &spec, NULL);
} while (err<0 && errno == EINTR);
}

checkExit();
}

usleep(part.pause * ns2us(frameDuration));

// For infinite parts, we've now played them at least once, so perhaps exit
if(exitPending() && !part.count)
break;
}

// free the textures for this part
if (!needSaveMem && part.count != 1) {
for (size_t j=0 ; j<fcount ; j++) {
const Animation::Frame& frame(part.frames[j]);
glDeleteTextures(1, &frame.tid);
}
}

if (needSaveMem) {
glDeleteTextures(1, &mTextureid);
}

}

ALOGD("waiting for media player to complete.");
struct timespec timeout;
clock_gettime(CLOCK_REALTIME, &timeout);
timeout.tv_sec += 5; //timeout after 5s.

pthread_mutex_lock(&mp_lock);
while (!isMPlayerCompleted) {
int err = pthread_cond_timedwait(&mp_cond, &mp_lock, &timeout);
if (err == ETIMEDOUT) {
break;
}
}
pthread_mutex_unlock(&mp_lock);
ALOGD("media player is completed.");

pthread_cond_destroy(&mp_cond);
pthread_mutex_destroy(&mp_lock);

return false;
}

在基本了解配置的工作流程后，接下来时怎么制作开bootanimation.zip包了，在准备好图片资源和写好配置文件后（具体配置可以参考我上传的bootanimation.zip 里面包含多个开机动画包或从手机pull一个出来），接下来打包压缩测试我们的开机动画包了，在压缩的时候注意一定要选择存储压缩，在Linux上压缩时可以用下面的命令

#以store方式压缩，进入配置文件当前的目录执行下面命令
zip -0 -r ../bootanimation.zip ./*

压缩完成后，会在上一级目录生成bootanimation.zip文件，我们可以通过以下命令测试生存的bootanimation文件

adb  root
adb remount
adb push bootanimation.zip system/media/
adb shell chmod 644 system/media/bootanimation.zip  #我测试的时候没改权限，也运行起来了，测试之前最好先把自己的bootanimation.zip备份一份，并记住权限
adb reboot

在开机以后，也可以执行下面的命令来运行开机动画

adb shell bootanimation
adb shell
setprop ctl.start bootanim #执行开机动画
getprop ctl.start bootanim #停止开机动画