Qualcomm GStreamer Plugins

Enable hardware supports on Qualcomm platform.

Qualcomm GStreamer Plugins是一系列高通平台下定制的开源插件，官网有插件的基本信息介绍，本章节将介绍其中几个在高通平台下进行音视频开发最常用的硬件相关的插件在开发过程中的一些坑，包括：qtivdec，qtivtransform，qtioverlay和omxh264enc。

这些插件的源码位于高通Linux源码的src/vendor/qcom/opensource/gst-plugins-qti-oss目录下，在Linux目录中，vendor目录下一般是各家厂商定制化的、非开源的内容，但假如在高通平台下使用dpkg --info查看对应插件库的信息，可以在Description中看到open-source，并且源码的开头是Linux内核所遵守的BSD许可协议。奇怪的是网上除了几个老旧的插件,能找到的就只有gst-plugins-mle-oss中的qtimlesnpe和qtimletflite，使用gst-inspect-1.0查看库遵守BSD许可协议，因此本章节所有代码均遵守BSD许可协议：

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