VENC视频编码

// 1.AscendCL初始化
aclRet = aclInit(nullptr);

// 2.运行管理资源申请（依次申请Device、Context、Stream）
aclrtContext context_;
aclrtStream stream_;
aclrtSetDevice(0);
aclrtCreateContext(&context_, 0);
aclrtCreateStream(&stream_);

// 3.创建执行回调函数的线程及线程函数
static bool runFlag = true;
void *ThreadFunc(void *arg)
{
     // Notice: create context for this thread
    int deviceId = 0;
    aclrtContext context = nullptr;
    aclError ret = aclrtCreateContext(&context, deviceId);
    INFO_LOG("process callback thread start ");
    while (runFlag) {
        // Notice: timeout 1000ms
        (void)aclrtProcessReport(1000);
    }
    // ......
    ret = aclrtDestroyContext(context);
    return (void*)0;
}

int createThreadErr = pthread_create(&threadId_, nullptr, ThreadFunc, nullptr);

// 4.创建回调函数
void callback(acldvppPicDesc *input, acldvppStreamDesc *outputStreamDesc, void *userdata)
{
    // 获取视频编码结果数据，并写入文件
    void *outputDev = acldvppGetStreamDescData(outputStreamDesc);
    uint32_t streamDescSize = acldvppGetStreamDescSize(outputStreamDesc);
    if (!Utils::WriteToFile(g_outFileFp, outputDev, streamDescSize)) {
        ERROR_LOG("write file:%s failed.", g_outFile.c_str());
    }
    INFO_LOG("success to callback, stream size:%u", streamDescSize);
}

// 5.创建视频编码处理通道时的通道描述信息，设置通道描述信息的属性，其中线程、callback回调函数需要用户提前创建
// vencChannelDesc_是aclvdecChannelDesc类型
vencChannelDesc_ = aclvencCreateChannelDesc();
auto ret = aclvencSetChannelDescThreadId(vencChannelDesc_, threadId_);
ret = aclvencSetChannelDescCallback(vencChannelDesc_, callback);
ret = aclvencSetChannelDescEnType(vencChannelDesc_, enType_);
ret = aclvencSetChannelDescPicFormat(vencChannelDesc_, format_);
ret = aclvencSetChannelDescPicWidth(vencChannelDesc_, 128);
ret = aclvencSetChannelDescPicHeight(vencChannelDesc_, 128);
ret = aclvencSetChannelDescKeyFrameInterval(vencChannelDesc_, 16);

// 6.创建视频码流处理的通道、单帧编码配置数据
ret = aclvencCreateChannel(vencChannelDesc_);
// vencFrameConfig_是aclvencFrameConfig类型
vencFrameConfig_ = aclvencCreateFrameConfig();

// 7.申请Device内存dataDev，存放视频编码的输入数据
// 7.1 读入图片数据
const char *fileName = "../dvpp_venc_128x128_nv12.yuv";
FILE *fp = fopen(fileName, "rb+");
fseek(fp, 0, SEEK_END);
long fileLenLong = ftell(fp);
fseek(fp, 0, SEEK_SET);
auto fileLen = static_cast<uint32_t>(fileLenLong);
uint32_t dataSize = fileLen;

// 调用aclrtGetRunMode接口获取软件栈的运行模式，如果调用aclrtGetRunMode接口获取软件栈的运行模式为ACL_HOST，则需要通过aclrtMemcpy接口将输入图片数据传输到Device，数据传输完成后，需及时释放内存；否则直接申请并使用Device的内存
aclrtRunMode runMode;
ret = aclrtGetRunMode(&runMode);
if（runMode == ACL_HOST） { 
    void *dataHost = malloc(fileLen);
    size_t readSize = fread(dataHost, 1, fileLen, fp)
    void *dataDev = nullptr;
    ret = acldvppMalloc(&dataDev, dataSize);
    ret = aclrtMemcpy(dataDev, dataSize, dataHost, fileLen, ACL_MEMCPY_HOST_TO_DEVICE);
    // 完成数据传输后，需及时释放内存
    free(dataHost);
} 
else { 
    ret = acldvppMalloc(&dataDev, dataSize);
}

// 8.执行视频编码
size_t g_vencCnt = 16;
// 8.1 创建输入图片描述信息，设置输入图片数据的内存地址和内存大小
inputPicputDesc_ = acldvppCreatePicDesc();
ret = acldvppSetPicDescData(inputPicputDesc_, dataDev);
ret = acldvppSetPicDescSize(inputPicputDesc_, dataSize);
// 8.2 设置单帧编码配置数据，不是结束帧
ret = aclvencSetFrameConfigEos(vencFrameConfig_, 0);
ret = aclvencSetFrameConfigForceIFrame(vencFrameConfig_, 0)
// 8.3 创建输出码流描述信息
acldvppStreamDesc *outputStreamDesc = nullptr;
// 8.4 执行视频编码
while (g_vencCnt > 0) {
        ret = aclvencSendFrame(vencChannelDesc_, inputPicputDesc_,
            static_cast<void *>(outputStreamDesc), vencFrameConfig_, nullptr);
        g_vencCnt--;
    }
// 8.5 设置单帧编码配置数据，是结束帧
ret = aclvencSetFrameConfigEos(vencFrameConfig_, 1);
ret = aclvencSetFrameConfigForceIFrame(vencFrameConfig_, 0)
// 8.6 执行最后一帧的视频编码
ret = aclvencSendFrame(vencChannelDesc_, nullptr, nullptr, vencFrameConfig_, nullptr);

// 9.释放资源
(void)aclvencDestroyChannel(vencChannelDesc_);
(void)aclvencDestroyChannelDesc(vencChannelDesc_);
(void)acldvppDestroyPicDesc(inputPicputDesc_);
(void)aclvencDestroyFrameConfig(vencFrameConfig_);
// 释放内存和销毁线程
(void)acldvppFree(inBufferDev_);
void *res = nullptr;
int joinThreadErr = pthread_join(threadId_, &res);

// 10. 释放运行管理资源（依次释放Stream、Context、Device）
aclrtDestroyStream(stream_);
aclrtDestroyContext(context_);
aclrtResetDevice(0);

// 11.AscendCL去初始化
aclRet = aclFinalize();
// ......