stagefright的codec---2

最重要的还是openmax的处理，只是看了一天，很多东西还需要再细看一下

        openmax 的IL层规定了一些接口，openmax分为core和instance，core加载instance，omax instance实现IL接口，提供给openmax框架调用，而omax instance就是特定平台实现自己codec的具体地方。

下面代码是qcom平台的建立自己omx具体方法的地方，omx 具体调用的就是component的方法，而具体的到底是什么方法是在omx il的api中规定好的。

void * qc_omx_create_component_wrapper(OMX_PTR obj_ptr)
{
    qc_omx_component *pThis        = (qc_omx_component *)obj_ptr;
    OMX_COMPONENTTYPE* component   = &(pThis->m_cmp);
    memset(&pThis->m_cmp,0,sizeof(OMX_COMPONENTTYPE));
    component->nSize               = sizeof(OMX_COMPONENTTYPE);
    component->nVersion.nVersion   = OMX_SPEC_VERSION;
    component->pApplicationPrivate = 0;
    component->pComponentPrivate   = obj_ptr;
    component->AllocateBuffer      = &qc_omx_component_allocate_buffer;
    component->FreeBuffer          = &qc_omx_component_free_buffer;
    component->GetParameter        = &qc_omx_component_get_parameter;
    component->SetParameter        = &qc_omx_component_set_parameter;
    component->SendCommand         = &qc_omx_component_send_command;
    component->FillThisBuffer      = &qc_omx_component_fill_this_buffer;
    component->EmptyThisBuffer     = &qc_omx_component_empty_this_buffer;
    component->GetState            = &qc_omx_component_get_state;
    component->GetComponentVersion = &qc_omx_component_get_version;
    component->GetConfig           = &qc_omx_component_get_config;
    component->SetConfig           = &qc_omx_component_set_config;
    component->GetExtensionIndex   = &qc_omx_component_get_extension_index;
    component->ComponentTunnelRequest = &qc_omx_component_tunnel_request;
    component->UseBuffer           = &qc_omx_component_use_buffer;
    component->SetCallbacks        = &qc_omx_component_set_callbacks;
    component->UseEGLImage         = &qc_omx_component_use_EGL_image;
    component->ComponentRoleEnum   = &qc_omx_component_role_enum;
    component->ComponentDeInit     = &qc_omx_component_deinit;
    return (void *)component;
}
qcom平台会继续调用自己实现的omx方法 www.zzzyk.com

摘自 shcalm的专栏

补充：移动开发 , Android ,